/*
  * MJPEG decoder

  * Copyright (c) 2000, 2001 Fabrice Bellard

  * Copyright (c) 2003 Alex Beregszaszi
  * Copyright (c) 2003-2004 Michael Niedermayer
  *

  * Support for external huffman table, various fixes (AVID workaround),
  * aspecting, new decode_frame mechanism and apple mjpeg-b support
  *                                  by Alex Beregszaszi
  *

  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 /**

  * @file

  * MJPEG decoder.
  */
 

 #include "libavutil/imgutils.h"

 #include "libavutil/avassert.h"

 #include "libavutil/opt.h"

 #include "avcodec.h"

 #include "blockdsp.h"

 #include "copy_block.h"

 #include "idctdsp.h"

 #include "internal.h"

 #include "jpegtables.h"

 #include "mjpeg.h"

 #include "mjpegdec.h"

 #include "jpeglsdec.h"

 #include "put_bits.h"

 #include "tiff.h"
 #include "exif.h"
 #include "bytestream.h"

 static int build_vlc(VLC *vlc, const uint8_t *bits_table,
                      const uint8_t *val_table, int nb_codes,
                      int use_static, int is_ac)

 {

     uint8_t huff_size[256] = { 0 };

     uint16_t huff_code[256];
     uint16_t huff_sym[256];
     int i;

     av_assert0(nb_codes <= 256);

     ff_mjpeg_build_huffman_codes(huff_size, huff_code, bits_table, val_table);

     for (i = 0; i < 256; i++)
         huff_sym[i] = i + 16 * is_ac;

     if (is_ac)
         huff_sym[0] = 16 * 256;

     return ff_init_vlc_sparse(vlc, 9, nb_codes, huff_size, 1, 1,
                               huff_code, 2, 2, huff_sym, 2, 2, use_static);

 }
 

 static void build_basic_mjpeg_vlc(MJpegDecodeContext *s)
 {

     build_vlc(&s->vlcs[0][0], avpriv_mjpeg_bits_dc_luminance,
               avpriv_mjpeg_val_dc, 12, 0, 0);
     build_vlc(&s->vlcs[0][1], avpriv_mjpeg_bits_dc_chrominance,
               avpriv_mjpeg_val_dc, 12, 0, 0);
     build_vlc(&s->vlcs[1][0], avpriv_mjpeg_bits_ac_luminance,
               avpriv_mjpeg_val_ac_luminance, 251, 0, 1);
     build_vlc(&s->vlcs[1][1], avpriv_mjpeg_bits_ac_chrominance,
               avpriv_mjpeg_val_ac_chrominance, 251, 0, 1);
     build_vlc(&s->vlcs[2][0], avpriv_mjpeg_bits_ac_luminance,
               avpriv_mjpeg_val_ac_luminance, 251, 0, 0);
     build_vlc(&s->vlcs[2][1], avpriv_mjpeg_bits_ac_chrominance,
               avpriv_mjpeg_val_ac_chrominance, 251, 0, 0);

 }
 

 static void parse_avid(MJpegDecodeContext *s, uint8_t *buf, int len)
 {
     s->buggy_avid = 1;
     if (len > 14 && buf[12] == 1) /* 1 - NTSC */
         s->interlace_polarity = 1;

     if (len > 14 && buf[12] == 2) /* 2 - PAL */
         s->interlace_polarity = 0;

     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
         av_log(s->avctx, AV_LOG_INFO, "AVID: len:%d %d\n", len, len > 14 ? buf[12] : -1);

 }
 

 static void init_idct(AVCodecContext *avctx)
 {
     MJpegDecodeContext *s = avctx->priv_data;
 
     ff_idctdsp_init(&s->idsp, avctx);
     ff_init_scantable(s->idsp.idct_permutation, &s->scantable,
                       ff_zigzag_direct);
 }
 

 av_cold int ff_mjpeg_decode_init(AVCodecContext *avctx)

 {
     MJpegDecodeContext *s = avctx->priv_data;
 

     if (!s->picture_ptr) {
         s->picture = av_frame_alloc();
         if (!s->picture)
             return AVERROR(ENOMEM);
         s->picture_ptr = s->picture;
     }

     s->avctx = avctx;

     ff_blockdsp_init(&s->bdsp, avctx);

     ff_hpeldsp_init(&s->hdsp, avctx->flags);

     init_idct(avctx);

     s->buffer_size   = 0;
     s->buffer        = NULL;
     s->start_code    = -1;

     s->first_picture = 1;

     s->got_picture   = 0;

     s->org_height    = avctx->coded_height;

     avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;

     avctx->colorspace = AVCOL_SPC_BT470BG;

     build_basic_mjpeg_vlc(s);

     if (s->extern_huff) {

         av_log(avctx, AV_LOG_INFO, "using external huffman table\n");

         init_get_bits(&s->gb, avctx->extradata, avctx->extradata_size * 8);

         if (ff_mjpeg_decode_dht(s)) {

             av_log(avctx, AV_LOG_ERROR,

                    "error using external huffman table, switching back to internal\n");

             build_basic_mjpeg_vlc(s);

         }

     }

     if (avctx->field_order == AV_FIELD_BB) { /* quicktime icefloe 019 */

         s->interlace_polarity = 1;           /* bottom field first */

         av_log(avctx, AV_LOG_DEBUG, "bottom field first\n");

     } else if (avctx->field_order == AV_FIELD_UNKNOWN) {
         if (avctx->codec_tag == AV_RL32("MJPG"))
             s->interlace_polarity = 1;

     }

 
     if (   avctx->extradata_size > 8
         && AV_RL32(avctx->extradata) == 0x2C
         && AV_RL32(avctx->extradata+4) == 0x18) {
         parse_avid(s, avctx->extradata, avctx->extradata_size);
     }
 

     if (avctx->codec->id == AV_CODEC_ID_AMV)

         s->flipped = 1;

 
     return 0;
 }
 
 
 /* quantize tables */

 int ff_mjpeg_decode_dqt(MJpegDecodeContext *s)

 {

     int len, index, i;

 
     len = get_bits(&s->gb, 16) - 2;
 

     if (8*len > get_bits_left(&s->gb)) {
         av_log(s->avctx, AV_LOG_ERROR, "dqt: len %d is too large\n", len);
         return AVERROR_INVALIDDATA;
     }
 

     while (len >= 65) {

         int pr = get_bits(&s->gb, 4);
         if (pr > 1) {
             av_log(s->avctx, AV_LOG_ERROR, "dqt: invalid precision\n");
             return AVERROR_INVALIDDATA;

         }
         index = get_bits(&s->gb, 4);
         if (index >= 4)
             return -1;
         av_log(s->avctx, AV_LOG_DEBUG, "index=%d\n", index);
         /* read quant table */

         for (i = 0; i < 64; i++) {

             s->quant_matrixes[index][i] = get_bits(&s->gb, pr ? 16 : 8);

         }
 

         // XXX FIXME fine-tune, and perhaps add dc too

         s->qscale[index] = FFMAX(s->quant_matrixes[index][1],
                                  s->quant_matrixes[index][8]) >> 1;

         av_log(s->avctx, AV_LOG_DEBUG, "qscale[%d]: %d\n",
                index, s->qscale[index]);

         len -= 1 + 64 * (1+pr);

     }
     return 0;
 }
 
 /* decode huffman tables and build VLC decoders */

 int ff_mjpeg_decode_dht(MJpegDecodeContext *s)

 {
     int len, index, i, class, n, v, code_max;
     uint8_t bits_table[17];
     uint8_t val_table[256];

     int ret = 0;

 
     len = get_bits(&s->gb, 16) - 2;
 

     if (8*len > get_bits_left(&s->gb)) {
         av_log(s->avctx, AV_LOG_ERROR, "dht: len %d is too large\n", len);
         return AVERROR_INVALIDDATA;
     }
 

     while (len > 0) {
         if (len < 17)

             return AVERROR_INVALIDDATA;

         class = get_bits(&s->gb, 4);
         if (class >= 2)

             return AVERROR_INVALIDDATA;

         index = get_bits(&s->gb, 4);
         if (index >= 4)

             return AVERROR_INVALIDDATA;

         n = 0;

         for (i = 1; i <= 16; i++) {

             bits_table[i] = get_bits(&s->gb, 8);
             n += bits_table[i];
         }
         len -= 17;
         if (len < n || n > 256)

             return AVERROR_INVALIDDATA;

 
         code_max = 0;

         for (i = 0; i < n; i++) {

             v = get_bits(&s->gb, 8);
             if (v > code_max)
                 code_max = v;
             val_table[i] = v;
         }
         len -= n;
 
         /* build VLC and flush previous vlc if present */

         ff_free_vlc(&s->vlcs[class][index]);

         av_log(s->avctx, AV_LOG_DEBUG, "class=%d index=%d nb_codes=%d\n",
                class, index, code_max + 1);

         if ((ret = build_vlc(&s->vlcs[class][index], bits_table, val_table,
                              code_max + 1, 0, class > 0)) < 0)
             return ret;

         if (class > 0) {

             ff_free_vlc(&s->vlcs[2][index]);

             if ((ret = build_vlc(&s->vlcs[2][index], bits_table, val_table,
                                  code_max + 1, 0, 0)) < 0)
                 return ret;

         }

     }
     return 0;
 }
 

 int ff_mjpeg_decode_sof(MJpegDecodeContext *s)

 {

     int len, nb_components, i, width, height, bits, ret;
     unsigned pix_fmt_id;

     int h_count[MAX_COMPONENTS] = { 0 };
     int v_count[MAX_COMPONENTS] = { 0 };

     s->cur_scan = 0;

     memset(s->upscale_h, 0, sizeof(s->upscale_h));
     memset(s->upscale_v, 0, sizeof(s->upscale_v));

     /* XXX: verify len field validity */

     len     = get_bits(&s->gb, 16);

     bits    = get_bits(&s->gb, 8);

     if (bits > 16 || bits < 1) {
         av_log(s->avctx, AV_LOG_ERROR, "bits %d is invalid\n", bits);
         return AVERROR_INVALIDDATA;
     }
 

     if (s->avctx->bits_per_raw_sample != bits) {

         av_log(s->avctx, s->avctx->bits_per_raw_sample > 0 ? AV_LOG_INFO : AV_LOG_DEBUG, "Changing bps from %d to %d\n", s->avctx->bits_per_raw_sample, bits);

         s->avctx->bits_per_raw_sample = bits;
         init_idct(s->avctx);
     }

     if (s->pegasus_rct)

         bits = 9;
     if (bits == 9 && !s->pegasus_rct)

         s->rct  = 1;    // FIXME ugly

     if(s->lossless && s->avctx->lowres){
         av_log(s->avctx, AV_LOG_ERROR, "lowres is not possible with lossless jpeg\n");
         return -1;
     }
 

     height = get_bits(&s->gb, 16);

     width  = get_bits(&s->gb, 16);

     // HACK for odd_height.mov
     if (s->interlaced && s->width == width && s->height == height + 1)

         height= s->height;
 
     av_log(s->avctx, AV_LOG_DEBUG, "sof0: picture: %dx%d\n", width, height);

     if (av_image_check_size(width, height, 0, s->avctx))

         return AVERROR_INVALIDDATA;

 
     nb_components = get_bits(&s->gb, 8);
     if (nb_components <= 0 ||
         nb_components > MAX_COMPONENTS)
         return -1;

     if (s->interlaced && (s->bottom_field == !s->interlace_polarity)) {
         if (nb_components != s->nb_components) {

             av_log(s->avctx, AV_LOG_ERROR,
                    "nb_components changing in interlaced picture\n");

             return AVERROR_INVALIDDATA;
         }
     }

     if (s->ls && !(bits <= 8 || nb_components == 1)) {

         avpriv_report_missing_feature(s->avctx,
                                       "JPEG-LS that is not <= 8 "
                                       "bits/component or 16-bit gray");

         return AVERROR_PATCHWELCOME;

     }
     s->nb_components = nb_components;

     s->h_max         = 1;
     s->v_max         = 1;
     for (i = 0; i < nb_components; i++) {

         /* component id */
         s->component_id[i] = get_bits(&s->gb, 8) - 1;

         h_count[i]         = get_bits(&s->gb, 4);
         v_count[i]         = get_bits(&s->gb, 4);

         /* compute hmax and vmax (only used in interleaved case) */

         if (h_count[i] > s->h_max)
             s->h_max = h_count[i];
         if (v_count[i] > s->v_max)
             s->v_max = v_count[i];

         s->quant_index[i] = get_bits(&s->gb, 8);

         if (s->quant_index[i] >= 4) {
             av_log(s->avctx, AV_LOG_ERROR, "quant_index is invalid\n");

             return AVERROR_INVALIDDATA;

         }

         if (!h_count[i] || !v_count[i]) {

             av_log(s->avctx, AV_LOG_ERROR,
                    "Invalid sampling factor in component %d %d:%d\n",

                    i, h_count[i], v_count[i]);

             return AVERROR_INVALIDDATA;
         }
 

         av_log(s->avctx, AV_LOG_DEBUG, "component %d %d:%d id: %d quant:%d\n",

                i, h_count[i], v_count[i],

                s->component_id[i], s->quant_index[i]);

     }

     if (   nb_components == 4
         && s->component_id[0] == 'C' - 1
         && s->component_id[1] == 'M' - 1
         && s->component_id[2] == 'Y' - 1
         && s->component_id[3] == 'K' - 1)
         s->adobe_transform = 0;

     if (s->ls && (s->h_max > 1 || s->v_max > 1)) {

         avpriv_report_missing_feature(s->avctx, "Subsampling in JPEG-LS");

         return AVERROR_PATCHWELCOME;

     }
 
 
     /* if different size, realloc/alloc picture */

     if (width != s->width || height != s->height || bits != s->bits ||
         memcmp(s->h_count, h_count, sizeof(h_count))                ||
         memcmp(s->v_count, v_count, sizeof(v_count))) {

         s->width      = width;
         s->height     = height;

         s->bits       = bits;

         memcpy(s->h_count, h_count, sizeof(h_count));
         memcpy(s->v_count, v_count, sizeof(v_count));

         s->interlaced = 0;

         s->got_picture = 0;

 
         /* test interlaced mode */

         if (s->first_picture   &&

             (s->multiscope != 2 || s->avctx->time_base.den >= 25 * s->avctx->time_base.num) &&

             s->org_height != 0 &&
             s->height < ((s->org_height * 3) / 4)) {

             s->interlaced                    = 1;
             s->bottom_field                  = s->interlace_polarity;

             s->picture_ptr->interlaced_frame = 1;

             s->picture_ptr->top_field_first  = !s->interlace_polarity;

             height *= 2;
         }
 

         ret = ff_set_dimensions(s->avctx, width, height);
         if (ret < 0)
             return ret;

 
         s->first_picture = 0;
     }
 

     if (s->got_picture && s->interlaced && (s->bottom_field == !s->interlace_polarity)) {

         if (s->progressive) {

             avpriv_request_sample(s->avctx, "progressively coded interlaced picture");

             return AVERROR_INVALIDDATA;
         }

     } else{

         if (s->v_max == 1 && s->h_max == 1 && s->lossless==1 && (nb_components==3 || nb_components==4))

             s->rgb = 1;
         else if (!s->lossless)
             s->rgb = 0;

     /* XXX: not complete test ! */

     pix_fmt_id = ((unsigned)s->h_count[0] << 28) | (s->v_count[0] << 24) |

                  (s->h_count[1] << 20) | (s->v_count[1] << 16) |
                  (s->h_count[2] << 12) | (s->v_count[2] <<  8) |
                  (s->h_count[3] <<  4) |  s->v_count[3];

     av_log(s->avctx, AV_LOG_DEBUG, "pix fmt id %x\n", pix_fmt_id);

     /* NOTE we do not allocate pictures large enough for the possible
      * padding of h/v_count being 4 */
     if (!(pix_fmt_id & 0xD0D0D0D0))
         pix_fmt_id -= (pix_fmt_id & 0xF0F0F0F0) >> 1;
     if (!(pix_fmt_id & 0x0D0D0D0D))
         pix_fmt_id -= (pix_fmt_id & 0x0F0F0F0F) >> 1;
 

     for (i = 0; i < 8; i++) {
         int j = 6 + (i&1) - (i&6);
         int is = (pix_fmt_id >> (4*i)) & 0xF;
         int js = (pix_fmt_id >> (4*j)) & 0xF;

 
         if (is == 1 && js != 2 && (i < 2 || i > 5))
             js = (pix_fmt_id >> ( 8 + 4*(i&1))) & 0xF;
         if (is == 1 && js != 2 && (i < 2 || i > 5))
             js = (pix_fmt_id >> (16 + 4*(i&1))) & 0xF;
 

         if (is == 1 && js == 2) {

             if (i & 1) s->upscale_h[j/2] = 1;
             else       s->upscale_v[j/2] = 1;

         }
     }
 

     switch (pix_fmt_id) {

     case 0x11111100:

         if (s->rgb)

             s->avctx->pix_fmt = s->bits <= 9 ? AV_PIX_FMT_BGR24 : AV_PIX_FMT_BGR48;

         else {
             if (s->component_id[0] == 'Q' && s->component_id[1] == 'F' && s->component_id[2] == 'A') {

                 s->avctx->pix_fmt = s->bits <= 8 ? AV_PIX_FMT_GBRP : AV_PIX_FMT_GBRP16;

             } else {

                 if (s->bits <= 8) s->avctx->pix_fmt = s->cs_itu601 ? AV_PIX_FMT_YUV444P : AV_PIX_FMT_YUVJ444P;
                 else              s->avctx->pix_fmt = AV_PIX_FMT_YUV444P16;

             s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;

             }

         }

         av_assert0(s->nb_components == 3);

         break;

     case 0x11111111:
         if (s->rgb)

             s->avctx->pix_fmt = s->bits <= 9 ? AV_PIX_FMT_ABGR : AV_PIX_FMT_RGBA64;

         else {

             if (s->adobe_transform == 0 && s->bits <= 8) {
                 s->avctx->pix_fmt = AV_PIX_FMT_GBRAP;
             } else {
                 s->avctx->pix_fmt = s->bits <= 8 ? AV_PIX_FMT_YUVA444P : AV_PIX_FMT_YUVA444P16;
                 s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;

             }

         }
         av_assert0(s->nb_components == 4);
         break;

     case 0x22111122:

     case 0x22111111:

         if (s->adobe_transform == 0 && s->bits <= 8) {
             s->avctx->pix_fmt = AV_PIX_FMT_GBRAP;

             s->upscale_v[1] = s->upscale_v[2] = 1;
             s->upscale_h[1] = s->upscale_h[2] = 1;

         } else if (s->adobe_transform == 2 && s->bits <= 8) {
             s->avctx->pix_fmt = AV_PIX_FMT_YUVA444P;

             s->upscale_v[1] = s->upscale_v[2] = 1;
             s->upscale_h[1] = s->upscale_h[2] = 1;

             s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;

         } else {
             if (s->bits <= 8) s->avctx->pix_fmt = AV_PIX_FMT_YUVA420P;
             else              s->avctx->pix_fmt = AV_PIX_FMT_YUVA420P16;
             s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
         }
         av_assert0(s->nb_components == 4);
         break;

     case 0x12121100:

     case 0x22122100:
     case 0x21211100:
     case 0x22211200:

         if (s->bits <= 8) s->avctx->pix_fmt = s->cs_itu601 ? AV_PIX_FMT_YUV444P : AV_PIX_FMT_YUVJ444P;
         else
             goto unk_pixfmt;

         s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
         break;
     case 0x22221100:

     case 0x22112200:

     case 0x11222200:
         if (s->bits <= 8) s->avctx->pix_fmt = s->cs_itu601 ? AV_PIX_FMT_YUV444P : AV_PIX_FMT_YUVJ444P;
         else
             goto unk_pixfmt;
         s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
         break;

     case 0x11000000:

     case 0x13000000:
     case 0x14000000:
     case 0x31000000:
     case 0x33000000:
     case 0x34000000:
     case 0x41000000:
     case 0x43000000:
     case 0x44000000:

         if(s->bits <= 8)

             s->avctx->pix_fmt = AV_PIX_FMT_GRAY8;

         else

             s->avctx->pix_fmt = AV_PIX_FMT_GRAY16;

         break;

     case 0x12111100:

     case 0x14121200:

     case 0x14111100:

     case 0x22211100:

     case 0x22112100:

         if (s->component_id[0] == 'Q' && s->component_id[1] == 'F' && s->component_id[2] == 'A') {
             if (s->bits <= 8) s->avctx->pix_fmt = AV_PIX_FMT_GBRP;
             else
                 goto unk_pixfmt;

             s->upscale_v[0] = s->upscale_v[1] = 1;

         } else {

             if (pix_fmt_id == 0x14111100)

                 s->upscale_v[1] = s->upscale_v[2] = 1;

             if (s->bits <= 8) s->avctx->pix_fmt = s->cs_itu601 ? AV_PIX_FMT_YUV440P : AV_PIX_FMT_YUVJ440P;
             else
                 goto unk_pixfmt;
             s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
         }

         break;

     case 0x21111100:

         if (s->component_id[0] == 'Q' && s->component_id[1] == 'F' && s->component_id[2] == 'A') {
             if (s->bits <= 8) s->avctx->pix_fmt = AV_PIX_FMT_GBRP;
             else
                 goto unk_pixfmt;

             s->upscale_h[0] = s->upscale_h[1] = 1;

         } else {
             if (s->bits <= 8) s->avctx->pix_fmt = s->cs_itu601 ? AV_PIX_FMT_YUV422P : AV_PIX_FMT_YUVJ422P;
             else              s->avctx->pix_fmt = AV_PIX_FMT_YUV422P16;
             s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
         }

         break;

     case 0x31111100:
         if (s->bits > 8)
             goto unk_pixfmt;
         s->avctx->pix_fmt = s->cs_itu601 ? AV_PIX_FMT_YUV444P : AV_PIX_FMT_YUVJ444P;
         s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
         s->upscale_h[1] = s->upscale_h[2] = 2;
         break;

     case 0x22121100:
     case 0x22111200:

         if (s->bits <= 8) s->avctx->pix_fmt = s->cs_itu601 ? AV_PIX_FMT_YUV422P : AV_PIX_FMT_YUVJ422P;
         else
             goto unk_pixfmt;

         s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
         break;

     case 0x22111100:

     case 0x42111100:

     case 0x24111100:

         if (s->bits <= 8) s->avctx->pix_fmt = s->cs_itu601 ? AV_PIX_FMT_YUV420P : AV_PIX_FMT_YUVJ420P;
         else              s->avctx->pix_fmt = AV_PIX_FMT_YUV420P16;

         s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;

         if (pix_fmt_id == 0x42111100) {

             if (s->bits > 8)
                 goto unk_pixfmt;

             s->upscale_h[1] = s->upscale_h[2] = 1;

         } else if (pix_fmt_id == 0x24111100) {

             if (s->bits > 8)
                 goto unk_pixfmt;

             s->upscale_v[1] = s->upscale_v[2] = 1;

         }

         break;

     case 0x41111100:

         if (s->bits <= 8) s->avctx->pix_fmt = s->cs_itu601 ? AV_PIX_FMT_YUV411P : AV_PIX_FMT_YUVJ411P;
         else
             goto unk_pixfmt;

         s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
         break;

     default:

 unk_pixfmt:

         av_log(s->avctx, AV_LOG_ERROR, "Unhandled pixel format 0x%x bits:%d\n", pix_fmt_id, s->bits);

         memset(s->upscale_h, 0, sizeof(s->upscale_h));
         memset(s->upscale_v, 0, sizeof(s->upscale_v));

         return AVERROR_PATCHWELCOME;

     }

     if ((AV_RB32(s->upscale_h) || AV_RB32(s->upscale_v)) && s->avctx->lowres) {

         av_log(s->avctx, AV_LOG_ERROR, "lowres not supported for weird subsampling\n");
         return AVERROR_PATCHWELCOME;
     }

     if (s->ls) {

         memset(s->upscale_h, 0, sizeof(s->upscale_h));
         memset(s->upscale_v, 0, sizeof(s->upscale_v));

         if (s->nb_components == 3) {

             s->avctx->pix_fmt = AV_PIX_FMT_RGB24;

         } else if (s->nb_components != 1) {
             av_log(s->avctx, AV_LOG_ERROR, "Unsupported number of components %d\n", s->nb_components);
             return AVERROR_PATCHWELCOME;
         } else if (s->palette_index && s->bits <= 8)

             s->avctx->pix_fmt = AV_PIX_FMT_PAL8;

         else if (s->bits <= 8)

             s->avctx->pix_fmt = AV_PIX_FMT_GRAY8;

         else

             s->avctx->pix_fmt = AV_PIX_FMT_GRAY16;

     }
 

     s->pix_desc = av_pix_fmt_desc_get(s->avctx->pix_fmt);
     if (!s->pix_desc) {
         av_log(s->avctx, AV_LOG_ERROR, "Could not get a pixel format descriptor.\n");
         return AVERROR_BUG;
     }
 

     if (s->avctx->skip_frame == AVDISCARD_ALL) {
         s->picture_ptr->pict_type = AV_PICTURE_TYPE_I;
         s->picture_ptr->key_frame = 1;
         s->got_picture            = 1;
         return 0;
     }
 

     av_frame_unref(s->picture_ptr);

     if (ff_get_buffer(s->avctx, s->picture_ptr, AV_GET_BUFFER_FLAG_REF) < 0)

         return -1;

     s->picture_ptr->pict_type = AV_PICTURE_TYPE_I;
     s->picture_ptr->key_frame = 1;
     s->got_picture            = 1;

     for (i = 0; i < 4; i++)

         s->linesize[i] = s->picture_ptr->linesize[i] << s->interlaced;

     ff_dlog(s->avctx, "%d %d %d %d %d %d\n",

             s->width, s->height, s->linesize[0], s->linesize[1],
             s->interlaced, s->avctx->height);

     if (len != (8 + (3 * nb_components)))

         av_log(s->avctx, AV_LOG_DEBUG, "decode_sof0: error, len(%d) mismatch\n", len);

     }

     if ((s->rgb && !s->lossless && !s->ls) ||
         (!s->rgb && s->ls && s->nb_components > 1)) {

         av_log(s->avctx, AV_LOG_ERROR, "Unsupported coding and pixel format combination\n");
         return AVERROR_PATCHWELCOME;
     }
 

     /* totally blank picture as progressive JPEG will only add details to it */

     if (s->progressive) {
         int bw = (width  + s->h_max * 8 - 1) / (s->h_max * 8);
         int bh = (height + s->v_max * 8 - 1) / (s->v_max * 8);
         for (i = 0; i < s->nb_components; i++) {

             int size = bw * bh * s->h_count[i] * s->v_count[i];
             av_freep(&s->blocks[i]);
             av_freep(&s->last_nnz[i]);

             s->blocks[i]       = av_mallocz_array(size, sizeof(**s->blocks));
             s->last_nnz[i]     = av_mallocz_array(size, sizeof(**s->last_nnz));

             if (!s->blocks[i] || !s->last_nnz[i])
                 return AVERROR(ENOMEM);

             s->block_stride[i] = bw * s->h_count[i];
         }
         memset(s->coefs_finished, 0, sizeof(s->coefs_finished));

     }
     return 0;
 }
 
 static inline int mjpeg_decode_dc(MJpegDecodeContext *s, int dc_index)
 {
     int code;
     code = get_vlc2(&s->gb, s->vlcs[0][dc_index].table, 9, 2);

     if (code < 0 || code > 16) {

         av_log(s->avctx, AV_LOG_WARNING,
                "mjpeg_decode_dc: bad vlc: %d:%d (%p)\n",
                0, dc_index, &s->vlcs[0][dc_index]);

         return 0xfffff;

     }
 

     if (code)

         return get_xbits(&s->gb, code);
     else
         return 0;
 }
 
 /* decode block and dequantize */

 static int decode_block(MJpegDecodeContext *s, int16_t *block, int component,

                         int dc_index, int ac_index, int16_t *quant_matrix)

 {
     int code, i, j, level, val;
 
     /* DC coef */
     val = mjpeg_decode_dc(s, dc_index);

     if (val == 0xfffff) {

         av_log(s->avctx, AV_LOG_ERROR, "error dc\n");

         return AVERROR_INVALIDDATA;

     }
     val = val * quant_matrix[0] + s->last_dc[component];

     val = FFMIN(val, 32767);

     s->last_dc[component] = val;
     block[0] = val;
     /* AC coefs */
     i = 0;

     {OPEN_READER(re, &s->gb);

     do {

         UPDATE_CACHE(re, &s->gb);

         GET_VLC(code, re, &s->gb, s->vlcs[1][ac_index].table, 9, 2);

 
         i += ((unsigned)code) >> 4;
             code &= 0xf;

         if (code) {
             if (code > MIN_CACHE_BITS - 16)

                 UPDATE_CACHE(re, &s->gb);

             {

                 int cache = GET_CACHE(re, &s->gb);
                 int sign  = (~cache) >> 31;
                 level     = (NEG_USR32(sign ^ cache,code) ^ sign) - sign;

             }
 

             LAST_SKIP_BITS(re, &s->gb, code);

             if (i > 63) {

                 av_log(s->avctx, AV_LOG_ERROR, "error count: %d\n", i);

                 return AVERROR_INVALIDDATA;

             }

             j        = s->scantable.permutated[i];

             block[j] = level * quant_matrix[i];

         }

     } while (i < 63);

     CLOSE_READER(re, &s->gb);}

 
     return 0;
 }
 

 static int decode_dc_progressive(MJpegDecodeContext *s, int16_t *block,

                                  int component, int dc_index,
                                  int16_t *quant_matrix, int Al)

 {
     int val;

     s->bdsp.clear_block(block);

     val = mjpeg_decode_dc(s, dc_index);

     if (val == 0xfffff) {

         av_log(s->avctx, AV_LOG_ERROR, "error dc\n");

         return AVERROR_INVALIDDATA;

     }

     val = (val * (quant_matrix[0] << Al)) + s->last_dc[component];

     s->last_dc[component] = val;
     block[0] = val;
     return 0;
 }
 

 /* decode block and dequantize - progressive JPEG version */

 static int decode_block_progressive(MJpegDecodeContext *s, int16_t *block,

                                     uint8_t *last_nnz, int ac_index,
                                     int16_t *quant_matrix,

                                     int ss, int se, int Al, int *EOBRUN)

 {
     int code, i, j, level, val, run;
 

     if (*EOBRUN) {

         (*EOBRUN)--;
         return 0;
     }

     {
         OPEN_READER(re, &s->gb);
         for (i = ss; ; i++) {
             UPDATE_CACHE(re, &s->gb);
             GET_VLC(code, re, &s->gb, s->vlcs[2][ac_index].table, 9, 2);

             run = ((unsigned) code) >> 4;
             code &= 0xF;
             if (code) {
                 i += run;
                 if (code > MIN_CACHE_BITS - 16)
                     UPDATE_CACHE(re, &s->gb);

                 {
                     int cache = GET_CACHE(re, &s->gb);
                     int sign  = (~cache) >> 31;
                     level     = (NEG_USR32(sign ^ cache,code) ^ sign) - sign;

                 }

 
                 LAST_SKIP_BITS(re, &s->gb, code);
 

                 if (i >= se) {

                     if (i == se) {
                         j = s->scantable.permutated[se];

                         block[j] = level * (quant_matrix[se] << Al);

                         break;
                     }
                     av_log(s->avctx, AV_LOG_ERROR, "error count: %d\n", i);

                     return AVERROR_INVALIDDATA;

                 }

                 j = s->scantable.permutated[i];

                 block[j] = level * (quant_matrix[i] << Al);

             } else {
                 if (run == 0xF) {// ZRL - skip 15 coefficients
                     i += 15;
                     if (i >= se) {
                         av_log(s->avctx, AV_LOG_ERROR, "ZRL overflow: %d\n", i);

                         return AVERROR_INVALIDDATA;

                     }
                 } else {
                     val = (1 << run);
                     if (run) {
                         UPDATE_CACHE(re, &s->gb);
                         val += NEG_USR32(GET_CACHE(re, &s->gb), run);
                         LAST_SKIP_BITS(re, &s->gb, run);
                     }
                     *EOBRUN = val - 1;
                     break;

                 }

             }
         }

         CLOSE_READER(re, &s->gb);

     }

 
     if (i > *last_nnz)

         *last_nnz = i;

     return 0;
 }
 

 #define REFINE_BIT(j) {                                             \
     UPDATE_CACHE(re, &s->gb);                                       \
     sign = block[j] >> 15;                                          \
     block[j] += SHOW_UBITS(re, &s->gb, 1) *                         \

                 ((quant_matrix[i] ^ sign) - sign) << Al;            \

     LAST_SKIP_BITS(re, &s->gb, 1);                                  \

 }
 

 #define ZERO_RUN                                                    \
 for (; ; i++) {                                                     \
     if (i > last) {                                                 \
         i += run;                                                   \
         if (i > se) {                                               \
             av_log(s->avctx, AV_LOG_ERROR, "error count: %d\n", i); \
             return -1;                                              \
         }                                                           \
         break;                                                      \
     }                                                               \
     j = s->scantable.permutated[i];                                 \
     if (block[j])                                                   \
         REFINE_BIT(j)                                               \
     else if (run-- == 0)                                            \
         break;                                                      \

 }
 
 /* decode block and dequantize - progressive JPEG refinement pass */

 static int decode_block_refinement(MJpegDecodeContext *s, int16_t *block,

                                    uint8_t *last_nnz,
                                    int ac_index, int16_t *quant_matrix,
                                    int ss, int se, int Al, int *EOBRUN)

 {

     int code, i = ss, j, sign, val, run;
     int last    = FFMIN(se, *last_nnz);

 
     OPEN_READER(re, &s->gb);

     if (*EOBRUN) {

         (*EOBRUN)--;

     } else {
         for (; ; i++) {

             UPDATE_CACHE(re, &s->gb);

             GET_VLC(code, re, &s->gb, s->vlcs[2][ac_index].table, 9, 2);

             if (code & 0xF) {

                 run = ((unsigned) code) >> 4;
                 UPDATE_CACHE(re, &s->gb);
                 val = SHOW_UBITS(re, &s->gb, 1);
                 LAST_SKIP_BITS(re, &s->gb, 1);
                 ZERO_RUN;
                 j = s->scantable.permutated[i];
                 val--;

                 block[j] = ((quant_matrix[i] << Al) ^ val) - val;

                 if (i == se) {
                     if (i > *last_nnz)

                         *last_nnz = i;

                     CLOSE_READER(re, &s->gb);

                     return 0;
                 }

             } else {

                 run = ((unsigned) code) >> 4;

                 if (run == 0xF) {

                     ZERO_RUN;

                 } else {

                     val = run;
                     run = (1 << run);

                     if (val) {

                         UPDATE_CACHE(re, &s->gb);
                         run += SHOW_UBITS(re, &s->gb, val);
                         LAST_SKIP_BITS(re, &s->gb, val);
                     }
                     *EOBRUN = run - 1;
                     break;
                 }
             }
         }
 

         if (i > *last_nnz)

             *last_nnz = i;
     }
 

     for (; i <= last; i++) {

         j = s->scantable.permutated[i];

         if (block[j])

             REFINE_BIT(j)
     }
     CLOSE_READER(re, &s->gb);

 
     return 0;
 }

 #undef REFINE_BIT
 #undef ZERO_RUN

 static int handle_rstn(MJpegDecodeContext *s, int nb_components)

 {
     int i;

     int reset = 0;
 

     if (s->restart_interval) {
         s->restart_count--;
         if(s->restart_count == 0 && s->avctx->codec_id == AV_CODEC_ID_THP){
             align_get_bits(&s->gb);
             for (i = 0; i < nb_components; i++) /* reset dc */

                 s->last_dc[i] = (4 << s->bits);

         }
 
         i = 8 + ((-get_bits_count(&s->gb)) & 7);
         /* skip RSTn */

         if (s->restart_count == 0) {

             if(   show_bits(&s->gb, i) == (1 << i) - 1
                || show_bits(&s->gb, i) == 0xFF) {
                 int pos = get_bits_count(&s->gb);
                 align_get_bits(&s->gb);
                 while (get_bits_left(&s->gb) >= 8 && show_bits(&s->gb, 8) == 0xFF)
                     skip_bits(&s->gb, 8);
                 if (get_bits_left(&s->gb) >= 8 && (get_bits(&s->gb, 8) & 0xF8) == 0xD0) {
                     for (i = 0; i < nb_components; i++) /* reset dc */

                         s->last_dc[i] = (4 << s->bits);

                     reset = 1;

                 } else
                     skip_bits_long(&s->gb, pos - get_bits_count(&s->gb));
             }

         }
     }

     return reset;

 }
 

 static int ljpeg_decode_rgb_scan(MJpegDecodeContext *s, int nb_components, int predictor, int point_transform)
 {

     int i, mb_x, mb_y;

     uint16_t (*buffer)[4];

     int left[4], top[4], topleft[4];

     const int linesize = s->linesize[0];

     const int mask     = ((1 << s->bits) - 1) << point_transform;

     int resync_mb_y = 0;
     int resync_mb_x = 0;

     if (s->nb_components != 3 && s->nb_components != 4)
         return AVERROR_INVALIDDATA;
     if (s->v_max != 1 || s->h_max != 1 || !s->lossless)
         return AVERROR_INVALIDDATA;
 
 

     s->restart_count = s->restart_interval;
 

     av_fast_malloc(&s->ljpeg_buffer, &s->ljpeg_buffer_size,
                    (unsigned)s->mb_width * 4 * sizeof(s->ljpeg_buffer[0][0]));
     buffer = s->ljpeg_buffer;

     for (i = 0; i < 4; i++)

         buffer[0][i] = 1 << (s->bits - 1);
 
     for (mb_y = 0; mb_y < s->mb_height; mb_y++) {

         uint8_t *ptr = s->picture_ptr->data[0] + (linesize * mb_y);

 
         if (s->interlaced && s->bottom_field)
             ptr += linesize >> 1;
 

         for (i = 0; i < 4; i++)

             top[i] = left[i] = topleft[i] = buffer[0][i];
 
         for (mb_x = 0; mb_x < s->mb_width; mb_x++) {

             int modified_predictor = predictor;
 
             if (s->restart_interval && !s->restart_count){

                 s->restart_count = s->restart_interval;

                 resync_mb_x = mb_x;
                 resync_mb_y = mb_y;

                 for(i=0; i<4; i++)

                     top[i] = left[i]= topleft[i]= 1 << (s->bits - 1);

             }

             if (mb_y == resync_mb_y || mb_y == resync_mb_y+1 && mb_x < resync_mb_x || !mb_x)

                 modified_predictor = 1;

             for (i=0;i<nb_components;i++) {

                 int pred, dc;

                 topleft[i] = top[i];
                 top[i]     = buffer[mb_x][i];

 
                 PREDICT(pred, topleft[i], top[i], left[i], modified_predictor);
 

                 dc = mjpeg_decode_dc(s, s->dc_index[i]);

                 if(dc == 0xFFFFF)

                     return -1;
 

                 left[i] = buffer[mb_x][i] =

                     mask & (pred + (dc * (1 << point_transform)));

             }
 
             if (s->restart_interval && !--s->restart_count) {
                 align_get_bits(&s->gb);
                 skip_bits(&s->gb, 16); /* skip RSTn */
             }
         }

         if (s->rct && s->nb_components == 4) {
             for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
                 ptr[4*mb_x + 2] = buffer[mb_x][0] - ((buffer[mb_x][1] + buffer[mb_x][2] - 0x200) >> 2);
                 ptr[4*mb_x + 1] = buffer[mb_x][1] + ptr[4*mb_x + 2];
                 ptr[4*mb_x + 3] = buffer[mb_x][2] + ptr[4*mb_x + 2];
                 ptr[4*mb_x + 0] = buffer[mb_x][3];
             }
         } else if (s->nb_components == 4) {

             for(i=0; i<nb_components; i++) {
                 int c= s->comp_index[i];

                 if (s->bits <= 8) {
                     for(mb_x = 0; mb_x < s->mb_width; mb_x++) {
                         ptr[4*mb_x+3-c] = buffer[mb_x][i];
                     }

                 } else if(s->bits == 9) {
                     return AVERROR_PATCHWELCOME;

                 } else {
                     for(mb_x = 0; mb_x < s->mb_width; mb_x++) {
                         ((uint16_t*)ptr)[4*mb_x+c] = buffer[mb_x][i];
                     }

                 }
             }
         } else if (s->rct) {

             for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
                 ptr[3*mb_x + 1] = buffer[mb_x][0] - ((buffer[mb_x][1] + buffer[mb_x][2] - 0x200) >> 2);
                 ptr[3*mb_x + 0] = buffer[mb_x][1] + ptr[3*mb_x + 1];
                 ptr[3*mb_x + 2] = buffer[mb_x][2] + ptr[3*mb_x + 1];

             }

         } else if (s->pegasus_rct) {
             for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
                 ptr[3*mb_x + 1] = buffer[mb_x][0] - ((buffer[mb_x][1] + buffer[mb_x][2]) >> 2);
                 ptr[3*mb_x + 0] = buffer[mb_x][1] + ptr[3*mb_x + 1];
                 ptr[3*mb_x + 2] = buffer[mb_x][2] + ptr[3*mb_x + 1];

             }

         } else {
             for(i=0; i<nb_components; i++) {

                 int c= s->comp_index[i];

                 if (s->bits <= 8) {
                     for(mb_x = 0; mb_x < s->mb_width; mb_x++) {
                         ptr[3*mb_x+2-c] = buffer[mb_x][i];
                     }

                 } else if(s->bits == 9) {
                     return AVERROR_PATCHWELCOME;

                 } else {
                     for(mb_x = 0; mb_x < s->mb_width; mb_x++) {
                         ((uint16_t*)ptr)[3*mb_x+2-c] = buffer[mb_x][i];
                     }

                 }

             }
         }
     }
     return 0;
 }
 

 static int ljpeg_decode_yuv_scan(MJpegDecodeContext *s, int predictor,

                                  int point_transform, int nb_components)

 {

     int i, mb_x, mb_y, mask;

     int bits= (s->bits+7)&~7;

     int resync_mb_y = 0;
     int resync_mb_x = 0;

 
     point_transform += bits - s->bits;

     mask = ((1 << s->bits) - 1) << point_transform;

     av_assert0(nb_components>=1 && nb_components<=4);

     for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
         for (mb_x = 0; mb_x < s->mb_width; mb_x++) {

             if (s->restart_interval && !s->restart_count){

                 s->restart_count = s->restart_interval;

                 resync_mb_x = mb_x;
                 resync_mb_y = mb_y;
             }

             if(!mb_x || mb_y == resync_mb_y || mb_y == resync_mb_y+1 && mb_x < resync_mb_x || s->interlaced){
                 int toprow  = mb_y == resync_mb_y || mb_y == resync_mb_y+1 && mb_x < resync_mb_x;
                 int leftcol = !mb_x || mb_y == resync_mb_y && mb_x == resync_mb_x;

                 for (i = 0; i < nb_components; i++) {

                     uint8_t *ptr;

                     uint16_t *ptr16;

                     int n, h, v, x, y, c, j, linesize;
                     n = s->nb_blocks[i];
                     c = s->comp_index[i];
                     h = s->h_scount[i];
                     v = s->v_scount[i];
                     x = 0;
                     y = 0;
                     linesize= s->linesize[c];
 

                     if(bits>8) linesize /= 2;
 

                     for(j=0; j<n; j++) {

                         int pred, dc;

                         dc = mjpeg_decode_dc(s, s->dc_index[i]);

                         if(dc == 0xFFFFF)

                             return -1;

                         if (   h * mb_x + x >= s->width
                             || v * mb_y + y >= s->height) {
                             // Nothing to do
                         } else if (bits<=8) {

                         ptr = s->picture_ptr->data[c] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap

                         if(y==0 && toprow){
                             if(x==0 && leftcol){

                                 pred= 1 << (bits - 1);

                             }else{
                                 pred= ptr[-1];
                             }
                         }else{

                             if(x==0 && leftcol){

                                 pred= ptr[-linesize];
                             }else{
                                 PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);
                             }
                         }
 
                         if (s->interlaced && s->bottom_field)
                             ptr += linesize >> 1;

                         pred &= mask;

                         *ptr= pred + (dc << point_transform);

                         }else{

                             ptr16 = (uint16_t*)(s->picture_ptr->data[c] + 2*(linesize * (v * mb_y + y)) + 2*(h * mb_x + x)); //FIXME optimize this crap

                             if(y==0 && toprow){
                                 if(x==0 && leftcol){

                                     pred= 1 << (bits - 1);
                                 }else{
                                     pred= ptr16[-1];
                                 }
                             }else{

                                 if(x==0 && leftcol){

                                     pred= ptr16[-linesize];
                                 }else{
                                     PREDICT(pred, ptr16[-linesize-1], ptr16[-linesize], ptr16[-1], predictor);
                                 }
                             }

                             if (s->interlaced && s->bottom_field)
                                 ptr16 += linesize >> 1;

                             pred &= mask;

                             *ptr16= pred + (dc << point_transform);
                         }

                         if (++x == h) {
                             x = 0;
                             y++;
                         }
                     }
                 }

             } else {
                 for (i = 0; i < nb_components; i++) {

                     uint8_t *ptr;

                     uint16_t *ptr16;

                     int n, h, v, x, y, c, j, linesize, dc;

                     n        = s->nb_blocks[i];
                     c        = s->comp_index[i];
                     h        = s->h_scount[i];
                     v        = s->v_scount[i];
                     x        = 0;
                     y        = 0;
                     linesize = s->linesize[c];

                     if(bits>8) linesize /= 2;
 

                     for (j = 0; j < n; j++) {

                         int pred;
 

                         dc = mjpeg_decode_dc(s, s->dc_index[i]);

                         if(dc == 0xFFFFF)

                             return -1;

                         if (   h * mb_x + x >= s->width
                             || v * mb_y + y >= s->height) {
                             // Nothing to do
                         } else if (bits<=8) {

                             ptr = s->picture_ptr->data[c] +

                               (linesize * (v * mb_y + y)) +
                               (h * mb_x + x); //FIXME optimize this crap
                             PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);

                             pred &= mask;

                             *ptr = pred + (dc << point_transform);

                         }else{

                             ptr16 = (uint16_t*)(s->picture_ptr->data[c] + 2*(linesize * (v * mb_y + y)) + 2*(h * mb_x + x)); //FIXME optimize this crap

                             PREDICT(pred, ptr16[-linesize-1], ptr16[-linesize], ptr16[-1], predictor);
 

                             pred &= mask;

                             *ptr16= pred + (dc << point_transform);
                         }

                         if (++x == h) {
                             x = 0;
                             y++;
                         }
                     }
                 }
             }
             if (s->restart_interval && !--s->restart_count) {
                 align_get_bits(&s->gb);
                 skip_bits(&s->gb, 16); /* skip RSTn */
             }
         }
     }
     return 0;
 }
 

 static av_always_inline void mjpeg_copy_block(MJpegDecodeContext *s,
                                               uint8_t *dst, const uint8_t *src,

                                               int linesize, int lowres)
 {
     switch (lowres) {

     case 0: s->hdsp.put_pixels_tab[1][0](dst, src, linesize, 8);

         break;
     case 1: copy_block4(dst, src, linesize, linesize, 4);
         break;
     case 2: copy_block2(dst, src, linesize, linesize, 2);
         break;
     case 3: *dst = *src;
         break;
     }
 }
 

 static void shift_output(MJpegDecodeContext *s, uint8_t *ptr, int linesize)
 {
     int block_x, block_y;

     int size = 8 >> s->avctx->lowres;

     if (s->bits > 8) {

         for (block_y=0; block_y<size; block_y++)
             for (block_x=0; block_x<size; block_x++)

                 *(uint16_t*)(ptr + 2*block_x + block_y*linesize) <<= 16 - s->bits;
     } else {

         for (block_y=0; block_y<size; block_y++)
             for (block_x=0; block_x<size; block_x++)

                 *(ptr + block_x + block_y*linesize) <<= 8 - s->bits;
     }
 }
 

 static int mjpeg_decode_scan(MJpegDecodeContext *s, int nb_components, int Ah,
                              int Al, const uint8_t *mb_bitmask,

                              int mb_bitmask_size,

                              const AVFrame *reference)
 {

     int i, mb_x, mb_y, chroma_h_shift, chroma_v_shift, chroma_width, chroma_height;

     uint8_t *data[MAX_COMPONENTS];

     const uint8_t *reference_data[MAX_COMPONENTS];

     int linesize[MAX_COMPONENTS];

     GetBitContext mb_bitmask_gb = {0}; // initialize to silence gcc warning

     int bytes_per_pixel = 1 + (s->bits > 8);

     if (mb_bitmask) {
         if (mb_bitmask_size != (s->mb_width * s->mb_height + 7)>>3) {
             av_log(s->avctx, AV_LOG_ERROR, "mb_bitmask_size mismatches\n");
             return AVERROR_INVALIDDATA;
         }

         init_get_bits(&mb_bitmask_gb, mb_bitmask, s->mb_width * s->mb_height);

     }

     s->restart_count = 0;

     av_pix_fmt_get_chroma_sub_sample(s->avctx->pix_fmt, &chroma_h_shift,
                                      &chroma_v_shift);

     chroma_width  = AV_CEIL_RSHIFT(s->width,  chroma_h_shift);
     chroma_height = AV_CEIL_RSHIFT(s->height, chroma_v_shift);

     for (i = 0; i < nb_components; i++) {
         int c   = s->comp_index[i];

         data[c] = s->picture_ptr->data[c];

         reference_data[c] = reference ? reference->data[c] : NULL;

         linesize[c] = s->linesize[c];

         s->coefs_finished[c] |= 1;

     }
 

     for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
         for (mb_x = 0; mb_x < s->mb_width; mb_x++) {

             const int copy_mb = mb_bitmask && !get_bits1(&mb_bitmask_gb);
 

             if (s->restart_interval && !s->restart_count)
                 s->restart_count = s->restart_interval;
 

             if (get_bits_left(&s->gb) < 0) {

                 av_log(s->avctx, AV_LOG_ERROR, "overread %d\n",

                        -get_bits_left(&s->gb));

                 return AVERROR_INVALIDDATA;

             }

             for (i = 0; i < nb_components; i++) {

                 uint8_t *ptr;
                 int n, h, v, x, y, c, j;

                 int block_offset;

                 n = s->nb_blocks[i];
                 c = s->comp_index[i];
                 h = s->h_scount[i];
                 v = s->v_scount[i];
                 x = 0;
                 y = 0;

                 for (j = 0; j < n; j++) {

                     block_offset = (((linesize[c] * (v * mb_y + y) * 8) +

                                      (h * mb_x + x) * 8 * bytes_per_pixel) >> s->avctx->lowres);

                     if (s->interlaced && s->bottom_field)

                         block_offset += linesize[c] >> 1;

                     if (   8*(h * mb_x + x) < ((c == 1) || (c == 2) ? chroma_width  : s->width)
                         && 8*(v * mb_y + y) < ((c == 1) || (c == 2) ? chroma_height : s->height)) {

                         ptr = data[c] + block_offset;
                     } else
                         ptr = NULL;

                     if (!s->progressive) {

                         if (copy_mb) {
                             if (ptr)
                                 mjpeg_copy_block(s, ptr, reference_data[c] + block_offset,
                                                 linesize[c], s->avctx->lowres);

                         } else {

                             s->bdsp.clear_block(s->block);

                             if (decode_block(s, s->block, i,
                                              s->dc_index[i], s->ac_index[i],

                                              s->quant_matrixes[s->quant_sindex[i]]) < 0) {

                                 av_log(s->avctx, AV_LOG_ERROR,
                                        "error y=%d x=%d\n", mb_y, mb_x);

                                 return AVERROR_INVALIDDATA;

                             }

                             if (ptr) {
                                 s->idsp.idct_put(ptr, linesize[c], s->block);
                                 if (s->bits & 7)
                                     shift_output(s, ptr, linesize[c]);
                             }

                         }

                     } else {

                         int block_idx  = s->block_stride[c] * (v * mb_y + y) +
                                          (h * mb_x + x);

                         int16_t *block = s->blocks[c][block_idx];

                         if (Ah)
                             block[0] += get_bits1(&s->gb) *

                                         s->quant_matrixes[s->quant_sindex[i]][0] << Al;

                         else if (decode_dc_progressive(s, block, i, s->dc_index[i],

                                                        s->quant_matrixes[s->quant_sindex[i]],

                                                        Al) < 0) {
                             av_log(s->avctx, AV_LOG_ERROR,
                                    "error y=%d x=%d\n", mb_y, mb_x);

                             return AVERROR_INVALIDDATA;

                         }
                     }

                     ff_dlog(s->avctx, "mb: %d %d processed\n", mb_y, mb_x);
                     ff_dlog(s->avctx, "%d %d %d %d %d %d %d %d \n",

                             mb_x, mb_y, x, y, c, s->bottom_field,
                             (v * mb_y + y) * 8, (h * mb_x + x) * 8);

                     if (++x == h) {
                         x = 0;
                         y++;
                     }
                 }
             }

             handle_rstn(s, nb_components);

         }
     }
     return 0;
 }
 

 static int mjpeg_decode_scan_progressive_ac(MJpegDecodeContext *s, int ss,
                                             int se, int Ah, int Al)
 {

     int mb_x, mb_y;
     int EOBRUN = 0;
     int c = s->comp_index[0];

     int16_t *quant_matrix = s->quant_matrixes[s->quant_sindex[0]];

     av_assert0(ss>=0 && Ah>=0 && Al>=0);
     if (se < ss || se > 63) {
         av_log(s->avctx, AV_LOG_ERROR, "SS/SE %d/%d is invalid\n", ss, se);

         return AVERROR_INVALIDDATA;
     }
 

     // s->coefs_finished is a bitmask for coefficients coded
     // ss and se are parameters telling start and end coefficients
     s->coefs_finished[c] |= (2ULL << se) - (1ULL << ss);

     s->restart_count = 0;
 

     for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
         int block_idx    = mb_y * s->block_stride[c];

         int16_t (*block)[64] = &s->blocks[c][block_idx];

         uint8_t *last_nnz    = &s->last_nnz[c][block_idx];
         for (mb_x = 0; mb_x < s->mb_width; mb_x++, block++, last_nnz++) {
                 int ret;

                 if (s->restart_interval && !s->restart_count)
                     s->restart_count = s->restart_interval;
 

                 if (Ah)
                     ret = decode_block_refinement(s, *block, last_nnz, s->ac_index[0],
                                                   quant_matrix, ss, se, Al, &EOBRUN);
                 else
                     ret = decode_block_progressive(s, *block, last_nnz, s->ac_index[0],
                                                    quant_matrix, ss, se, Al, &EOBRUN);
                 if (ret < 0) {
                     av_log(s->avctx, AV_LOG_ERROR,
                            "error y=%d x=%d\n", mb_y, mb_x);

                     return AVERROR_INVALIDDATA;

                 }
 

             if (handle_rstn(s, 0))
                 EOBRUN = 0;

         }
     }
     return 0;
 }
 

 static void mjpeg_idct_scan_progressive_ac(MJpegDecodeContext *s)
 {
     int mb_x, mb_y;
     int c;
     const int bytes_per_pixel = 1 + (s->bits > 8);
     const int block_size = s->lossless ? 1 : 8;
 
     for (c = 0; c < s->nb_components; c++) {
         uint8_t *data = s->picture_ptr->data[c];
         int linesize  = s->linesize[c];
         int h = s->h_max / s->h_count[c];
         int v = s->v_max / s->v_count[c];
         int mb_width     = (s->width  + h * block_size - 1) / (h * block_size);
         int mb_height    = (s->height + v * block_size - 1) / (v * block_size);
 
         if (~s->coefs_finished[c])
             av_log(s->avctx, AV_LOG_WARNING, "component %d is incomplete\n", c);
 
         if (s->interlaced && s->bottom_field)
             data += linesize >> 1;
 
         for (mb_y = 0; mb_y < mb_height; mb_y++) {
             uint8_t *ptr     = data + (mb_y * linesize * 8 >> s->avctx->lowres);
             int block_idx    = mb_y * s->block_stride[c];
             int16_t (*block)[64] = &s->blocks[c][block_idx];
             for (mb_x = 0; mb_x < mb_width; mb_x++, block++) {
                 s->idsp.idct_put(ptr, linesize, *block);
                 if (s->bits & 7)
                     shift_output(s, ptr, linesize);
                 ptr += bytes_per_pixel*8 >> s->avctx->lowres;
             }
         }
     }
 }
 

 int ff_mjpeg_decode_sos(MJpegDecodeContext *s, const uint8_t *mb_bitmask,

                         int mb_bitmask_size, const AVFrame *reference)

 {
     int len, nb_components, i, h, v, predictor, point_transform;

     int index, id, ret;

     const int block_size = s->lossless ? 1 : 8;

     int ilv, prev_shift;
 

     if (!s->got_picture) {
         av_log(s->avctx, AV_LOG_WARNING,
                 "Can not process SOS before SOF, skipping\n");
         return -1;
     }
 
     av_assert0(s->picture_ptr->data[0]);

     /* XXX: verify len field validity */
     len = get_bits(&s->gb, 16);
     nb_components = get_bits(&s->gb, 8);

     if (nb_components == 0 || nb_components > MAX_COMPONENTS) {
         av_log(s->avctx, AV_LOG_ERROR,
                "decode_sos: nb_components (%d) unsupported\n", nb_components);

         return AVERROR_PATCHWELCOME;

     }

     if (len != 6 + 2 * nb_components) {

         av_log(s->avctx, AV_LOG_ERROR, "decode_sos: invalid len (%d)\n", len);

         return AVERROR_INVALIDDATA;

     }

     for (i = 0; i < nb_components; i++) {

         id = get_bits(&s->gb, 8) - 1;
         av_log(s->avctx, AV_LOG_DEBUG, "component: %d\n", id);
         /* find component index */

         for (index = 0; index < s->nb_components; index++)

             if (id == s->component_id[index])
                 break;

         if (index == s->nb_components) {
             av_log(s->avctx, AV_LOG_ERROR,
                    "decode_sos: index(%d) out of components\n", index);

             return AVERROR_INVALIDDATA;

         }

         /* Metasoft MJPEG codec has Cb and Cr swapped */
         if (s->avctx->codec_tag == MKTAG('M', 'T', 'S', 'J')
             && nb_components == 3 && s->nb_components == 3 && i)
             index = 3 - i;

         s->quant_sindex[i] = s->quant_index[index];

         s->nb_blocks[i] = s->h_count[index] * s->v_count[index];
         s->h_scount[i]  = s->h_count[index];
         s->v_scount[i]  = s->v_count[index];
 

         if(nb_components == 3 && s->nb_components == 3 && s->avctx->pix_fmt == AV_PIX_FMT_GBR24P)

             index = (i+2)%3;

         if(nb_components == 1 && s->nb_components == 3 && s->avctx->pix_fmt == AV_PIX_FMT_GBR24P)

             index = (index+2)%3;

         s->comp_index[i] = index;
 
         s->dc_index[i] = get_bits(&s->gb, 4);
         s->ac_index[i] = get_bits(&s->gb, 4);
 
         if (s->dc_index[i] <  0 || s->ac_index[i] < 0 ||
             s->dc_index[i] >= 4 || s->ac_index[i] >= 4)
             goto out_of_range;

         if (!s->vlcs[0][s->dc_index[i]].table || !(s->progressive ? s->vlcs[2][s->ac_index[0]].table : s->vlcs[1][s->ac_index[i]].table))

             goto out_of_range;

     }
 

     predictor = get_bits(&s->gb, 8);       /* JPEG Ss / lossless JPEG predictor /JPEG-LS NEAR */
     ilv = get_bits(&s->gb, 8);             /* JPEG Se / JPEG-LS ILV */

     if(s->avctx->codec_tag != AV_RL32("CJPG")){

         prev_shift      = get_bits(&s->gb, 4); /* Ah */
         point_transform = get_bits(&s->gb, 4); /* Al */

     }else

         prev_shift = point_transform = 0;

 
     if (nb_components > 1) {
         /* interleaved stream */
         s->mb_width  = (s->width  + s->h_max * block_size - 1) / (s->h_max * block_size);
         s->mb_height = (s->height + s->v_max * block_size - 1) / (s->v_max * block_size);

     } else if (!s->ls) { /* skip this for JPEG-LS */

         h = s->h_max / s->h_scount[0];
         v = s->v_max / s->v_scount[0];

         s->mb_width     = (s->width  + h * block_size - 1) / (h * block_size);
         s->mb_height    = (s->height + v * block_size - 1) / (v * block_size);

         s->nb_blocks[0] = 1;

         s->h_scount[0]  = 1;
         s->v_scount[0]  = 1;

     }
 

     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
         av_log(s->avctx, AV_LOG_DEBUG, "%s %s p:%d >>:%d ilv:%d bits:%d skip:%d %s comp:%d\n",
                s->lossless ? "lossless" : "sequential DCT", s->rgb ? "RGB" : "",

                predictor, point_transform, ilv, s->bits, s->mjpb_skiptosod,

                s->pegasus_rct ? "PRCT" : (s->rct ? "RCT" : ""), nb_components);

 
 
     /* mjpeg-b can have padding bytes between sos and image data, skip them */
     for (i = s->mjpb_skiptosod; i > 0; i--)
         skip_bits(&s->gb, 8);
 

 next_field:
     for (i = 0; i < nb_components; i++)

         s->last_dc[i] = (4 << s->bits);

     if (s->lossless) {

         av_assert0(s->picture_ptr == s->picture);

         if (CONFIG_JPEGLS_DECODER && s->ls) {
 //            for () {

 //            reset_ls_coding_parameters(s, 0);
 

             if ((ret = ff_jpegls_decode_picture(s, predictor,
                                                 point_transform, ilv)) < 0)
                 return ret;

         } else {
             if (s->rgb) {

                 if ((ret = ljpeg_decode_rgb_scan(s, nb_components, predictor, point_transform)) < 0)

                     return ret;

             } else {

                 if ((ret = ljpeg_decode_yuv_scan(s, predictor,

                                                  point_transform,
                                                  nb_components)) < 0)

                     return ret;

             }
         }

     } else {
         if (s->progressive && predictor) {

             av_assert0(s->picture_ptr == s->picture);

             if ((ret = mjpeg_decode_scan_progressive_ac(s, predictor,
                                                         ilv, prev_shift,

                                                         point_transform)) < 0)

                 return ret;

         } else {

             if ((ret = mjpeg_decode_scan(s, nb_components,
                                          prev_shift, point_transform,

                                          mb_bitmask, mb_bitmask_size, reference)) < 0)

                 return ret;

         }

     }

 
     if (s->interlaced &&
         get_bits_left(&s->gb) > 32 &&
         show_bits(&s->gb, 8) == 0xFF) {
         GetBitContext bak = s->gb;

         align_get_bits(&bak);

         if (show_bits(&bak, 16) == 0xFFD1) {

             av_log(s->avctx, AV_LOG_DEBUG, "AVRn interlaced picture marker found\n");

             s->gb = bak;
             skip_bits(&s->gb, 16);
             s->bottom_field ^= 1;
 
             goto next_field;
         }
     }
 

     emms_c();
     return 0;
  out_of_range:
     av_log(s->avctx, AV_LOG_ERROR, "decode_sos: ac/dc index out of range\n");

     return AVERROR_INVALIDDATA;

 }
 
 static int mjpeg_decode_dri(MJpegDecodeContext *s)
 {
     if (get_bits(&s->gb, 16) != 4)

         return AVERROR_INVALIDDATA;

     s->restart_interval = get_bits(&s->gb, 16);

     s->restart_count    = 0;
     av_log(s->avctx, AV_LOG_DEBUG, "restart interval: %d\n",
            s->restart_interval);

 
     return 0;
 }
 
 static int mjpeg_decode_app(MJpegDecodeContext *s)
 {
     int len, id, i;
 
     len = get_bits(&s->gb, 16);

     if (len < 6)

         return AVERROR_INVALIDDATA;

     if (8 * len > get_bits_left(&s->gb))

         return AVERROR_INVALIDDATA;

     id   = get_bits_long(&s->gb, 32);

     len -= 6;
 

     if (s->avctx->debug & FF_DEBUG_STARTCODE) {
         char id_str[32];
         av_get_codec_tag_string(id_str, sizeof(id_str), av_bswap32(id));
         av_log(s->avctx, AV_LOG_DEBUG, "APPx (%s / %8X) len=%d\n", id_str, id, len);
     }

     /* Buggy AVID, it puts EOI only at every 10th frame. */
     /* Also, this fourcc is used by non-avid files too, it holds some
        information, but it's always present in AVID-created files. */

     if (id == AV_RB32("AVI1")) {

         /* structure:
             4bytes      AVI1
             1bytes      polarity
             1bytes      always zero
             4bytes      field_size
             4bytes      field_size_less_padding
         */
             s->buggy_avid = 1;

         i = get_bits(&s->gb, 8); len--;

         av_log(s->avctx, AV_LOG_DEBUG, "polarity %d\n", i);

 #if 0
         skip_bits(&s->gb, 8);
         skip_bits(&s->gb, 32);
         skip_bits(&s->gb, 32);
         len -= 10;
 #endif
         goto out;
     }
 
 //    len -= 2;
 

     if (id == AV_RB32("JFIF")) {

         int t_w, t_h, v1, v2;
         skip_bits(&s->gb, 8); /* the trailing zero-byte */

         v1 = get_bits(&s->gb, 8);
         v2 = get_bits(&s->gb, 8);

         skip_bits(&s->gb, 8);
 

         s->avctx->sample_aspect_ratio.num = get_bits(&s->gb, 16);
         s->avctx->sample_aspect_ratio.den = get_bits(&s->gb, 16);

         if (   s->avctx->sample_aspect_ratio.num <= 0
             || s->avctx->sample_aspect_ratio.den <= 0) {
             s->avctx->sample_aspect_ratio.num = 0;
             s->avctx->sample_aspect_ratio.den = 1;
         }

 
         if (s->avctx->debug & FF_DEBUG_PICT_INFO)

             av_log(s->avctx, AV_LOG_INFO,
                    "mjpeg: JFIF header found (version: %x.%x) SAR=%d/%d\n",
                    v1, v2,
                    s->avctx->sample_aspect_ratio.num,
                    s->avctx->sample_aspect_ratio.den);

 
         t_w = get_bits(&s->gb, 8);
         t_h = get_bits(&s->gb, 8);

         if (t_w && t_h) {

             /* skip thumbnail */

             if (len -10 - (t_w * t_h * 3) > 0)
                 len -= t_w * t_h * 3;

         }
         len -= 10;
         goto out;
     }
 

     if (   id == AV_RB32("Adob")
         && len >= 7
         && show_bits(&s->gb, 8) == 'e'
         && show_bits_long(&s->gb, 32) != AV_RB32("e_CM")) {
         skip_bits(&s->gb,  8); /* 'e' */

         skip_bits(&s->gb, 16); /* version */
         skip_bits(&s->gb, 16); /* flags0 */
         skip_bits(&s->gb, 16); /* flags1 */

         s->adobe_transform = get_bits(&s->gb,  8);
         if (s->avctx->debug & FF_DEBUG_PICT_INFO)
             av_log(s->avctx, AV_LOG_INFO, "mjpeg: Adobe header found, transform=%d\n", s->adobe_transform);

         len -= 7;
         goto out;
     }
 

     if (id == AV_RB32("LJIF")) {

         int rgb = s->rgb;
         int pegasus_rct = s->pegasus_rct;

         if (s->avctx->debug & FF_DEBUG_PICT_INFO)

             av_log(s->avctx, AV_LOG_INFO,
                    "Pegasus lossless jpeg header found\n");

         skip_bits(&s->gb, 16); /* version ? */

         skip_bits(&s->gb, 16); /* unknown always 0? */
         skip_bits(&s->gb, 16); /* unknown always 0? */
         skip_bits(&s->gb, 16); /* unknown always 0? */

         switch (i=get_bits(&s->gb, 8)) {

         case 1:

             rgb         = 1;
             pegasus_rct = 0;

             break;
         case 2:

             rgb         = 1;
             pegasus_rct = 1;

             break;
         default:

             av_log(s->avctx, AV_LOG_ERROR, "unknown colorspace %d\n", i);

         }

         len -= 9;

         if (s->got_picture)
             if (rgb != s->rgb || pegasus_rct != s->pegasus_rct) {
                 av_log(s->avctx, AV_LOG_WARNING, "Mismatching LJIF tag\n");
                 goto out;
             }
 
         s->rgb = rgb;
         s->pegasus_rct = pegasus_rct;
 

         goto out;
     }

     if (id == AV_RL32("colr") && len > 0) {
         s->colr = get_bits(&s->gb, 8);
         if (s->avctx->debug & FF_DEBUG_PICT_INFO)
             av_log(s->avctx, AV_LOG_INFO, "COLR %d\n", s->colr);
         len --;
         goto out;
     }

     if (id == AV_RL32("xfrm") && len > 0) {
         s->xfrm = get_bits(&s->gb, 8);
         if (s->avctx->debug & FF_DEBUG_PICT_INFO)
             av_log(s->avctx, AV_LOG_INFO, "XFRM %d\n", s->xfrm);
         len --;
         goto out;
     }

     /* JPS extension by VRex */
     if (s->start_code == APP3 && id == AV_RB32("_JPS") && len >= 10) {
         int flags, layout, type;
         if (s->avctx->debug & FF_DEBUG_PICT_INFO)
             av_log(s->avctx, AV_LOG_INFO, "_JPSJPS_\n");
 
         skip_bits(&s->gb, 32); len -= 4;  /* JPS_ */
         skip_bits(&s->gb, 16); len -= 2;  /* block length */
         skip_bits(&s->gb, 8);             /* reserved */
         flags  = get_bits(&s->gb, 8);
         layout = get_bits(&s->gb, 8);
         type   = get_bits(&s->gb, 8);
         len -= 4;
 
         s->stereo3d = av_stereo3d_alloc();
         if (!s->stereo3d) {
             goto out;
         }
         if (type == 0) {
             s->stereo3d->type = AV_STEREO3D_2D;
         } else if (type == 1) {
             switch (layout) {
             case 0x01:
                 s->stereo3d->type = AV_STEREO3D_LINES;
                 break;
             case 0x02:
                 s->stereo3d->type = AV_STEREO3D_SIDEBYSIDE;
                 break;
             case 0x03:
                 s->stereo3d->type = AV_STEREO3D_TOPBOTTOM;
                 break;
             }
             if (!(flags & 0x04)) {
                 s->stereo3d->flags = AV_STEREO3D_FLAG_INVERT;
             }
         }
         goto out;
     }
 

     /* EXIF metadata */

     if (s->start_code == APP1 && id == AV_RB32("Exif") && len >= 2) {

         GetByteContext gbytes;
         int ret, le, ifd_offset, bytes_read;
         const uint8_t *aligned;
 
         skip_bits(&s->gb, 16); // skip padding
         len -= 2;
 
         // init byte wise reading
         aligned = align_get_bits(&s->gb);
         bytestream2_init(&gbytes, aligned, len);
 
         // read TIFF header
         ret = ff_tdecode_header(&gbytes, &le, &ifd_offset);
         if (ret) {
             av_log(s->avctx, AV_LOG_ERROR, "mjpeg: invalid TIFF header in EXIF data\n");

         } else {

             bytestream2_seek(&gbytes, ifd_offset, SEEK_SET);

             // read 0th IFD and store the metadata
             // (return values > 0 indicate the presence of subimage metadata)
             ret = avpriv_exif_decode_ifd(s->avctx, &gbytes, le, 0, &s->exif_metadata);
             if (ret < 0) {
                 av_log(s->avctx, AV_LOG_ERROR, "mjpeg: error decoding EXIF data\n");
             }

         }
 
         bytes_read = bytestream2_tell(&gbytes);
         skip_bits(&s->gb, bytes_read << 3);
         len -= bytes_read;
 
         goto out;
     }
 

     /* Apple MJPEG-A */

     if ((s->start_code == APP1) && (len > (0x28 - 8))) {
         id   = get_bits_long(&s->gb, 32);

         len -= 4;

         /* Apple MJPEG-A */

         if (id == AV_RB32("mjpg")) {

 #if 0
             skip_bits(&s->gb, 32); /* field size */
             skip_bits(&s->gb, 32); /* pad field size */
             skip_bits(&s->gb, 32); /* next off */
             skip_bits(&s->gb, 32); /* quant off */
             skip_bits(&s->gb, 32); /* huff off */
             skip_bits(&s->gb, 32); /* image off */
             skip_bits(&s->gb, 32); /* scan off */
             skip_bits(&s->gb, 32); /* data off */
 #endif
             if (s->avctx->debug & FF_DEBUG_PICT_INFO)
                 av_log(s->avctx, AV_LOG_INFO, "mjpeg: Apple MJPEG-A header found\n");
         }
     }
 
 out:
     /* slow but needed for extreme adobe jpegs */
     if (len < 0)

         av_log(s->avctx, AV_LOG_ERROR,
                "mjpeg: error, decode_app parser read over the end\n");
     while (--len > 0)

         skip_bits(&s->gb, 8);
 
     return 0;
 }
 
 static int mjpeg_decode_com(MJpegDecodeContext *s)
 {
     int len = get_bits(&s->gb, 16);

     if (len >= 2 && 8 * len - 16 <= get_bits_left(&s->gb)) {

         int i;

         char *cbuf = av_malloc(len - 1);

         if (!cbuf)
             return AVERROR(ENOMEM);

         for (i = 0; i < len - 2; i++)
             cbuf[i] = get_bits(&s->gb, 8);
         if (i > 0 && cbuf[i - 1] == '\n')
             cbuf[i - 1] = 0;
         else
             cbuf[i] = 0;

         if (s->avctx->debug & FF_DEBUG_PICT_INFO)

             av_log(s->avctx, AV_LOG_INFO, "comment: '%s'\n", cbuf);

 
         /* buggy avid, it puts EOI only at every 10th frame */

         if (!strncmp(cbuf, "AVID", 4)) {
             parse_avid(s, cbuf, len);

         } else if (!strcmp(cbuf, "CS=ITU601"))
             s->cs_itu601 = 1;

         else if ((!strncmp(cbuf, "Intel(R) JPEG Library, version 1", 32) && s->avctx->codec_tag) ||
                  (!strncmp(cbuf, "Metasoft MJPEG Codec", 20)))

             s->flipped = 1;

         else if (!strcmp(cbuf, "MULTISCOPE II")) {
             s->avctx->sample_aspect_ratio = (AVRational) { 1, 2 };
             s->multiscope = 2;

         }

 
         av_free(cbuf);

     }
 
     return 0;
 }
 
 /* return the 8 bit start code value and update the search
    state. Return -1 if no start code found */

 static int find_marker(const uint8_t **pbuf_ptr, const uint8_t *buf_end)

 {

     const uint8_t *buf_ptr;

     unsigned int v, v2;
     int val;

     int skipped = 0;

 
     buf_ptr = *pbuf_ptr;

     while (buf_end - buf_ptr > 1) {

         v  = *buf_ptr++;

         v2 = *buf_ptr;
         if ((v == 0xff) && (v2 >= 0xc0) && (v2 <= 0xfe) && buf_ptr < buf_end) {
             val = *buf_ptr++;
             goto found;
         }
         skipped++;
     }

     buf_ptr = buf_end;

     val = -1;
 found:

     ff_dlog(NULL, "find_marker skipped %d bytes\n", skipped);

     *pbuf_ptr = buf_ptr;
     return val;
 }
 

 int ff_mjpeg_find_marker(MJpegDecodeContext *s,
                          const uint8_t **buf_ptr, const uint8_t *buf_end,

                          const uint8_t **unescaped_buf_ptr,
                          int *unescaped_buf_size)

 {
     int start_code;

     start_code = find_marker(buf_ptr, buf_end);

     av_fast_padded_malloc(&s->buffer, &s->buffer_size, buf_end - *buf_ptr);
     if (!s->buffer)
         return AVERROR(ENOMEM);

     /* unescape buffer of SOS, use special treatment for JPEG-LS */
     if (start_code == SOS && !s->ls) {
         const uint8_t *src = *buf_ptr;

         const uint8_t *ptr = src;

         uint8_t *dst = s->buffer;

         #define copy_data_segment(skip) do {       \

             ptrdiff_t length = (ptr - src) - (skip);  \

             if (length > 0) {                         \
                 memcpy(dst, src, length);             \
                 dst += length;                        \
                 src = ptr;                            \
             }                                         \
         } while (0)
 
         if (s->avctx->codec_id == AV_CODEC_ID_THP) {
             ptr = buf_end;
             copy_data_segment(0);
         } else {
             while (ptr < buf_end) {
                 uint8_t x = *(ptr++);

                 if (x == 0xff) {

                     ptrdiff_t skip = 0;

                     while (ptr < buf_end && x == 0xff) {
                         x = *(ptr++);
                         skip++;
                     }

                     /* 0xFF, 0xFF, ... */
                     if (skip > 1) {
                         copy_data_segment(skip);
 
                         /* decrement src as it is equal to ptr after the
                          * copy_data_segment macro and we might want to
                          * copy the current value of x later on */
                         src--;
                     }
 
                     if (x < 0xd0 || x > 0xd7) {
                         copy_data_segment(1);
                         if (x)
                             break;
                     }

                 }

             }

             if (src < ptr)
                 copy_data_segment(0);

         }

         #undef copy_data_segment
 

         *unescaped_buf_ptr  = s->buffer;
         *unescaped_buf_size = dst - s->buffer;

         memset(s->buffer + *unescaped_buf_size, 0,

                AV_INPUT_BUFFER_PADDING_SIZE);

         av_log(s->avctx, AV_LOG_DEBUG, "escaping removed %"PTRDIFF_SPECIFIER" bytes\n",

                (buf_end - *buf_ptr) - (dst - s->buffer));
     } else if (start_code == SOS && s->ls) {
         const uint8_t *src = *buf_ptr;
         uint8_t *dst  = s->buffer;
         int bit_count = 0;
         int t = 0, b = 0;
         PutBitContext pb;
 
         /* find marker */
         while (src + t < buf_end) {
             uint8_t x = src[t++];
             if (x == 0xff) {
                 while ((src + t < buf_end) && x == 0xff)
                     x = src[t++];
                 if (x & 0x80) {

                     t -= FFMIN(2, t);

                     break;

                 }

             }
         }
         bit_count = t * 8;
         init_put_bits(&pb, dst, t);
 
         /* unescape bitstream */
         while (b < t) {
             uint8_t x = src[b++];
             put_bits(&pb, 8, x);

             if (x == 0xFF && b < t) {

                 x = src[b++];

                 if (x & 0x80) {
                     av_log(s->avctx, AV_LOG_WARNING, "Invalid escape sequence\n");
                     x &= 0x7f;
                 }

                 put_bits(&pb, 7, x);
                 bit_count--;
             }
         }
         flush_put_bits(&pb);
 
         *unescaped_buf_ptr  = dst;
         *unescaped_buf_size = (bit_count + 7) >> 3;

         memset(s->buffer + *unescaped_buf_size, 0,

                AV_INPUT_BUFFER_PADDING_SIZE);

     } else {
         *unescaped_buf_ptr  = *buf_ptr;
         *unescaped_buf_size = buf_end - *buf_ptr;
     }

 
     return start_code;
 }
 

 int ff_mjpeg_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,

                           AVPacket *avpkt)

 {

     AVFrame     *frame = data;

     const uint8_t *buf = avpkt->data;

     int buf_size       = avpkt->size;

     MJpegDecodeContext *s = avctx->priv_data;
     const uint8_t *buf_end, *buf_ptr;
     const uint8_t *unescaped_buf_ptr;

     int hshift, vshift;

     int unescaped_buf_size;
     int start_code;

     int i, index;

     int ret = 0;

     int is16bit;

     av_dict_free(&s->exif_metadata);

     av_freep(&s->stereo3d);

     s->adobe_transform = -1;

     buf_ptr = buf;
     buf_end = buf + buf_size;
     while (buf_ptr < buf_end) {
         /* find start next marker */
         start_code = ff_mjpeg_find_marker(s, &buf_ptr, buf_end,

                                           &unescaped_buf_ptr,
                                           &unescaped_buf_size);
         /* EOF */
         if (start_code < 0) {

             break;

         } else if (unescaped_buf_size > INT_MAX / 8) {
             av_log(avctx, AV_LOG_ERROR,
                    "MJPEG packet 0x%x too big (%d/%d), corrupt data?\n",

                    start_code, unescaped_buf_size, buf_size);

             return AVERROR_INVALIDDATA;

         }

         av_log(avctx, AV_LOG_DEBUG, "marker=%x avail_size_in_buf=%"PTRDIFF_SPECIFIER"\n",

                start_code, buf_end - buf_ptr);

         ret = init_get_bits8(&s->gb, unescaped_buf_ptr, unescaped_buf_size);
 
         if (ret < 0) {

             av_log(avctx, AV_LOG_ERROR, "invalid buffer\n");
             goto fail;
         }

         s->start_code = start_code;
         if (s->avctx->debug & FF_DEBUG_STARTCODE)
             av_log(avctx, AV_LOG_DEBUG, "startcode: %X\n", start_code);

         /* process markers */
         if (start_code >= 0xd0 && start_code <= 0xd7)
             av_log(avctx, AV_LOG_DEBUG,
                    "restart marker: %d\n", start_code & 0x0f);
             /* APP fields */
         else if (start_code >= APP0 && start_code <= APP15)
             mjpeg_decode_app(s);
             /* Comment */

         else if (start_code == COM) {
             ret = mjpeg_decode_com(s);
             if (ret < 0)
                 return ret;
         }

         ret = -1;
 

         if (!CONFIG_JPEGLS_DECODER &&
             (start_code == SOF48 || start_code == LSE)) {
             av_log(avctx, AV_LOG_ERROR, "JPEG-LS support not enabled.\n");
             return AVERROR(ENOSYS);
         }

         if (avctx->skip_frame == AVDISCARD_ALL) {
             switch(start_code) {
             case SOF0:
             case SOF1:
             case SOF2:
             case SOF3:
             case SOF48:
             case SOI:
             case SOS:
             case EOI:
                 break;
             default:
                 goto skip;
             }
         }
 

         switch (start_code) {
         case SOI:
             s->restart_interval = 0;
             s->restart_count    = 0;
             /* nothing to do on SOI */
             break;
         case DQT:
             ff_mjpeg_decode_dqt(s);
             break;
         case DHT:
             if ((ret = ff_mjpeg_decode_dht(s)) < 0) {
                 av_log(avctx, AV_LOG_ERROR, "huffman table decode error\n");

                 goto fail;

             }
             break;
         case SOF0:
         case SOF1:
             s->lossless    = 0;
             s->ls          = 0;
             s->progressive = 0;
             if ((ret = ff_mjpeg_decode_sof(s)) < 0)

                 goto fail;

             break;
         case SOF2:
             s->lossless    = 0;
             s->ls          = 0;
             s->progressive = 1;
             if ((ret = ff_mjpeg_decode_sof(s)) < 0)

                 goto fail;

             break;
         case SOF3:

             s->avctx->properties |= FF_CODEC_PROPERTY_LOSSLESS;

             s->lossless    = 1;
             s->ls          = 0;
             s->progressive = 0;
             if ((ret = ff_mjpeg_decode_sof(s)) < 0)

                 goto fail;

             break;
         case SOF48:

             s->avctx->properties |= FF_CODEC_PROPERTY_LOSSLESS;

             s->lossless    = 1;
             s->ls          = 1;
             s->progressive = 0;
             if ((ret = ff_mjpeg_decode_sof(s)) < 0)

                 goto fail;

             break;
         case LSE:
             if (!CONFIG_JPEGLS_DECODER ||
                 (ret = ff_jpegls_decode_lse(s)) < 0)

                 goto fail;

             break;
         case EOI:

 eoi_parser:

             if (avctx->skip_frame != AVDISCARD_ALL && s->progressive && s->cur_scan && s->got_picture)
                 mjpeg_idct_scan_progressive_ac(s);

             s->cur_scan = 0;

             if (!s->got_picture) {
                 av_log(avctx, AV_LOG_WARNING,
                        "Found EOI before any SOF, ignoring\n");

                 break;
             }

             if (s->interlaced) {
                 s->bottom_field ^= 1;
                 /* if not bottom field, do not output image yet */
                 if (s->bottom_field == !s->interlace_polarity)

                     break;

             }

             if (avctx->skip_frame == AVDISCARD_ALL) {
                 s->got_picture = 0;
                 goto the_end_no_picture;
             }

             if ((ret = av_frame_ref(frame, s->picture_ptr)) < 0)

                 return ret;
             *got_frame = 1;

             s->got_picture = 0;
 
             if (!s->lossless) {
                 int qp = FFMAX3(s->qscale[0],
                                 s->qscale[1],
                                 s->qscale[2]);
                 int qpw = (s->width + 15) / 16;
                 AVBufferRef *qp_table_buf = av_buffer_alloc(qpw);
                 if (qp_table_buf) {
                     memset(qp_table_buf->data, qp, qpw);
                     av_frame_set_qp_table(data, qp_table_buf, 0, FF_QSCALE_TYPE_MPEG1);

                 }

                 if(avctx->debug & FF_DEBUG_QP)
                     av_log(avctx, AV_LOG_DEBUG, "QP: %d\n", qp);

             }

             goto the_end;
         case SOS:

             s->cur_scan++;

             if (avctx->skip_frame == AVDISCARD_ALL)
                 break;
 

             if ((ret = ff_mjpeg_decode_sos(s, NULL, 0, NULL)) < 0 &&

                 (avctx->err_recognition & AV_EF_EXPLODE))

                 goto fail;

             break;
         case DRI:
             mjpeg_decode_dri(s);
             break;
         case SOF5:
         case SOF6:
         case SOF7:
         case SOF9:
         case SOF10:
         case SOF11:
         case SOF13:
         case SOF14:
         case SOF15:
         case JPG:
             av_log(avctx, AV_LOG_ERROR,
                    "mjpeg: unsupported coding type (%x)\n", start_code);
             break;

         }

 skip:

         /* eof process start code */
         buf_ptr += (get_bits_count(&s->gb) + 7) / 8;
         av_log(avctx, AV_LOG_DEBUG,
                "marker parser used %d bytes (%d bits)\n",
                (get_bits_count(&s->gb) + 7) / 8, get_bits_count(&s->gb));

     }

     if (s->got_picture && s->cur_scan) {

         av_log(avctx, AV_LOG_WARNING, "EOI missing, emulating\n");
         goto eoi_parser;
     }

     av_log(avctx, AV_LOG_FATAL, "No JPEG data found in image\n");

     return AVERROR_INVALIDDATA;

 fail:

     s->got_picture = 0;

     return ret;

 the_end:

     is16bit = av_pix_fmt_desc_get(s->avctx->pix_fmt)->comp[0].step > 1;

     if (AV_RB32(s->upscale_h)) {

         int p;

         av_assert0(avctx->pix_fmt == AV_PIX_FMT_YUVJ444P ||
                    avctx->pix_fmt == AV_PIX_FMT_YUV444P  ||
                    avctx->pix_fmt == AV_PIX_FMT_YUVJ440P ||

                    avctx->pix_fmt == AV_PIX_FMT_YUV440P  ||

                    avctx->pix_fmt == AV_PIX_FMT_YUVA444P ||

                    avctx->pix_fmt == AV_PIX_FMT_YUVJ420P ||
                    avctx->pix_fmt == AV_PIX_FMT_YUV420P  ||

                    avctx->pix_fmt == AV_PIX_FMT_YUV420P16||

                    avctx->pix_fmt == AV_PIX_FMT_YUVA420P  ||
                    avctx->pix_fmt == AV_PIX_FMT_YUVA420P16||

                    avctx->pix_fmt == AV_PIX_FMT_GBRP     ||

                    avctx->pix_fmt == AV_PIX_FMT_GBRAP
                   );

         avcodec_get_chroma_sub_sample(s->avctx->pix_fmt, &hshift, &vshift);

         av_assert0(s->nb_components == av_pix_fmt_count_planes(s->picture_ptr->format));
         for (p = 0; p<s->nb_components; p++) {

             uint8_t *line = s->picture_ptr->data[p];

             int w = s->width;

             int h = s->height;

             if (!s->upscale_h[p])

                 continue;

             if (p==1 || p==2) {

                 w = AV_CEIL_RSHIFT(w, hshift);
                 h = AV_CEIL_RSHIFT(h, vshift);

             }

             if (s->upscale_v[p])

                 h = (h+1)>>1;

             av_assert0(w > 0);

             for (i = 0; i < h; i++) {

                 if (s->upscale_h[p] == 1) {
                     if (is16bit) ((uint16_t*)line)[w - 1] = ((uint16_t*)line)[(w - 1) / 2];
                     else                      line[w - 1] = line[(w - 1) / 2];
                     for (index = w - 2; index > 0; index--) {
                         if (is16bit)
                             ((uint16_t*)line)[index] = (((uint16_t*)line)[index / 2] + ((uint16_t*)line)[(index + 1) / 2]) >> 1;
                         else
                             line[index] = (line[index / 2] + line[(index + 1) / 2]) >> 1;
                     }
                 } else if (s->upscale_h[p] == 2) {
                     if (is16bit) {

                         ((uint16_t*)line)[w - 1] = ((uint16_t*)line)[(w - 1) / 3];
                         if (w > 1)
                             ((uint16_t*)line)[w - 2] = ((uint16_t*)line)[w - 1];

                     } else {

                         line[w - 1] = line[(w - 1) / 3];
                         if (w > 1)
                             line[w - 2] = line[w - 1];

                     }
                     for (index = w - 3; index > 0; index--) {
                         line[index] = (line[index / 3] + line[(index + 1) / 3] + line[(index + 2) / 3] + 1) / 3;
                     }

                 }

                 line += s->linesize[p];
             }

         }
     }

     if (AV_RB32(s->upscale_v)) {

         int p;

         av_assert0(avctx->pix_fmt == AV_PIX_FMT_YUVJ444P ||
                    avctx->pix_fmt == AV_PIX_FMT_YUV444P  ||
                    avctx->pix_fmt == AV_PIX_FMT_YUVJ422P ||

                    avctx->pix_fmt == AV_PIX_FMT_YUV422P  ||

                    avctx->pix_fmt == AV_PIX_FMT_YUVJ420P ||
                    avctx->pix_fmt == AV_PIX_FMT_YUV420P  ||

                    avctx->pix_fmt == AV_PIX_FMT_YUV440P  ||
                    avctx->pix_fmt == AV_PIX_FMT_YUVJ440P ||

                    avctx->pix_fmt == AV_PIX_FMT_YUVA444P ||

                    avctx->pix_fmt == AV_PIX_FMT_YUVA420P  ||
                    avctx->pix_fmt == AV_PIX_FMT_YUVA420P16||

                    avctx->pix_fmt == AV_PIX_FMT_GBRP     ||

                    avctx->pix_fmt == AV_PIX_FMT_GBRAP
                    );

         avcodec_get_chroma_sub_sample(s->avctx->pix_fmt, &hshift, &vshift);

         av_assert0(s->nb_components == av_pix_fmt_count_planes(s->picture_ptr->format));
         for (p = 0; p < s->nb_components; p++) {

             uint8_t *dst;

             int w = s->width;

             int h = s->height;

             if (!s->upscale_v[p])

                 continue;

             if (p==1 || p==2) {

                 w = AV_CEIL_RSHIFT(w, hshift);
                 h = AV_CEIL_RSHIFT(h, vshift);

             }
             dst = &((uint8_t *)s->picture_ptr->data[p])[(h - 1) * s->linesize[p]];
             for (i = h - 1; i; i--) {

                 uint8_t *src1 = &((uint8_t *)s->picture_ptr->data[p])[i / 2 * s->linesize[p]];
                 uint8_t *src2 = &((uint8_t *)s->picture_ptr->data[p])[(i + 1) / 2 * s->linesize[p]];

                 if (src1 == src2 || i == h - 1) {

                     memcpy(dst, src1, w);
                 } else {
                     for (index = 0; index < w; index++)
                         dst[index] = (src1[index] + src2[index]) >> 1;
                 }
                 dst -= s->linesize[p];

             }
         }
     }

     if (s->flipped) {

         int j;

         avcodec_get_chroma_sub_sample(s->avctx->pix_fmt, &hshift, &vshift);

         av_assert0(s->nb_components == av_pix_fmt_count_planes(s->picture_ptr->format));
         for (index=0; index<s->nb_components; index++) {

             uint8_t *dst = s->picture_ptr->data[index];

             int w = s->picture_ptr->width;
             int h = s->picture_ptr->height;

             if(index && index<3){

                 w = AV_CEIL_RSHIFT(w, hshift);
                 h = AV_CEIL_RSHIFT(h, vshift);

             }
             if(dst){

                 uint8_t *dst2 = dst + s->picture_ptr->linesize[index]*(h-1);

                 for (i=0; i<h/2; i++) {
                     for (j=0; j<w; j++)
                         FFSWAP(int, dst[j], dst2[j]);

                     dst  += s->picture_ptr->linesize[index];
                     dst2 -= s->picture_ptr->linesize[index];

                 }
             }
         }

     }
     if (s->adobe_transform == 0 && s->avctx->pix_fmt == AV_PIX_FMT_GBRAP) {
         int w = s->picture_ptr->width;
         int h = s->picture_ptr->height;

         av_assert0(s->nb_components == 4);

         for (i=0; i<h; i++) {
             int j;
             uint8_t *dst[4];
             for (index=0; index<4; index++) {
                 dst[index] =   s->picture_ptr->data[index]
                              + s->picture_ptr->linesize[index]*i;
             }
             for (j=0; j<w; j++) {
                 int k = dst[3][j];
                 int r = dst[0][j] * k;
                 int g = dst[1][j] * k;
                 int b = dst[2][j] * k;
                 dst[0][j] = g*257 >> 16;
                 dst[1][j] = b*257 >> 16;
                 dst[2][j] = r*257 >> 16;
                 dst[3][j] = 255;
             }
         }

     }
     if (s->adobe_transform == 2 && s->avctx->pix_fmt == AV_PIX_FMT_YUVA444P) {
         int w = s->picture_ptr->width;
         int h = s->picture_ptr->height;

         av_assert0(s->nb_components == 4);

         for (i=0; i<h; i++) {
             int j;
             uint8_t *dst[4];
             for (index=0; index<4; index++) {
                 dst[index] =   s->picture_ptr->data[index]
                              + s->picture_ptr->linesize[index]*i;
             }
             for (j=0; j<w; j++) {
                 int k = dst[3][j];
                 int r = (255 - dst[0][j]) * k;
                 int g = (128 - dst[1][j]) * k;
                 int b = (128 - dst[2][j]) * k;
                 dst[0][j] = r*257 >> 16;
                 dst[1][j] = (g*257 >> 16) + 128;
                 dst[2][j] = (b*257 >> 16) + 128;
                 dst[3][j] = 255;
             }
         }

     }
 

     if (s->stereo3d) {
         AVStereo3D *stereo = av_stereo3d_create_side_data(data);
         if (stereo) {
             stereo->type  = s->stereo3d->type;
             stereo->flags = s->stereo3d->flags;
         }
         av_freep(&s->stereo3d);
     }
 

     av_dict_copy(avpriv_frame_get_metadatap(data), s->exif_metadata, 0);
     av_dict_free(&s->exif_metadata);
 

 the_end_no_picture:

     av_log(avctx, AV_LOG_DEBUG, "decode frame unused %"PTRDIFF_SPECIFIER" bytes\n",

            buf_end - buf_ptr);
 //  return buf_end - buf_ptr;

     return buf_ptr - buf;
 }
 

 av_cold int ff_mjpeg_decode_end(AVCodecContext *avctx)

 {
     MJpegDecodeContext *s = avctx->priv_data;
     int i, j;
 

     if (s->interlaced && s->bottom_field == !s->interlace_polarity && s->got_picture && !avctx->frame_number) {
         av_log(avctx, AV_LOG_INFO, "Single field\n");
     }
 

     if (s->picture) {
         av_frame_free(&s->picture);
         s->picture_ptr = NULL;
     } else if (s->picture_ptr)

         av_frame_unref(s->picture_ptr);

     av_freep(&s->buffer);

     av_freep(&s->stereo3d);

     av_freep(&s->ljpeg_buffer);

     s->ljpeg_buffer_size = 0;

     for (i = 0; i < 3; i++) {
         for (j = 0; j < 4; j++)

             ff_free_vlc(&s->vlcs[i][j]);

     }

     for (i = 0; i < MAX_COMPONENTS; i++) {

         av_freep(&s->blocks[i]);
         av_freep(&s->last_nnz[i]);
     }

     av_dict_free(&s->exif_metadata);

     return 0;
 }
 

 static void decode_flush(AVCodecContext *avctx)
 {
     MJpegDecodeContext *s = avctx->priv_data;
     s->got_picture = 0;
 }
 

 #if CONFIG_MJPEG_DECODER

 #define OFFSET(x) offsetof(MJpegDecodeContext, x)
 #define VD AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_DECODING_PARAM
 static const AVOption options[] = {

     { "extern_huff", "Use external huffman table.",

       OFFSET(extern_huff), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, VD },

     { NULL },
 };
 
 static const AVClass mjpegdec_class = {
     .class_name = "MJPEG decoder",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,
 };
 

 AVCodec ff_mjpeg_decoder = {

     .name           = "mjpeg",

     .long_name      = NULL_IF_CONFIG_SMALL("MJPEG (Motion JPEG)"),

     .type           = AVMEDIA_TYPE_VIDEO,

     .id             = AV_CODEC_ID_MJPEG,

     .priv_data_size = sizeof(MJpegDecodeContext),
     .init           = ff_mjpeg_decode_init,
     .close          = ff_mjpeg_decode_end,
     .decode         = ff_mjpeg_decode_frame,

     .flush          = decode_flush,

     .capabilities   = AV_CODEC_CAP_DR1,

     .max_lowres     = 3,

     .priv_class     = &mjpegdec_class,

     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE |
                       FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM,

 };

 #endif
 #if CONFIG_THP_DECODER

 AVCodec ff_thp_decoder = {

     .name           = "thp",

     .long_name      = NULL_IF_CONFIG_SMALL("Nintendo Gamecube THP video"),

     .type           = AVMEDIA_TYPE_VIDEO,

     .id             = AV_CODEC_ID_THP,

     .priv_data_size = sizeof(MJpegDecodeContext),
     .init           = ff_mjpeg_decode_init,
     .close          = ff_mjpeg_decode_end,
     .decode         = ff_mjpeg_decode_frame,

     .flush          = decode_flush,

     .capabilities   = AV_CODEC_CAP_DR1,

     .max_lowres     = 3,

     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,

 };

 #endif