/*
  * huffyuv decoder
  *
  * Copyright (c) 2002-2003 Michael Niedermayer <michaelni@gmx.at>
  *
  * see http://www.pcisys.net/~melanson/codecs/huffyuv.txt for a description of
  * the algorithm used
  *

  * 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
  * huffyuv decoder
  */
 
 #include "avcodec.h"
 #include "dsputil.h"
 #include "get_bits.h"
 #include "huffyuv.h"
 #include "thread.h"
 
 #define classic_shift_luma_table_size 42
 static const unsigned char classic_shift_luma[classic_shift_luma_table_size + FF_INPUT_BUFFER_PADDING_SIZE] = {
   34,36,35,69,135,232,9,16,10,24,11,23,12,16,13,10,14,8,15,8,
   16,8,17,20,16,10,207,206,205,236,11,8,10,21,9,23,8,8,199,70,

   69,68, 0,
   0,0,0,0,0,0,0,0,

 };
 
 #define classic_shift_chroma_table_size 59
 static const unsigned char classic_shift_chroma[classic_shift_chroma_table_size + FF_INPUT_BUFFER_PADDING_SIZE] = {
   66,36,37,38,39,40,41,75,76,77,110,239,144,81,82,83,84,85,118,183,
   56,57,88,89,56,89,154,57,58,57,26,141,57,56,58,57,58,57,184,119,

   214,245,116,83,82,49,80,79,78,77,44,75,41,40,39,38,37,36,34, 0,
   0,0,0,0,0,0,0,0,

 };
 
 static const unsigned char classic_add_luma[256] = {
     3,  9,  5, 12, 10, 35, 32, 29, 27, 50, 48, 45, 44, 41, 39, 37,
    73, 70, 68, 65, 64, 61, 58, 56, 53, 50, 49, 46, 44, 41, 38, 36,
    68, 65, 63, 61, 58, 55, 53, 51, 48, 46, 45, 43, 41, 39, 38, 36,
    35, 33, 32, 30, 29, 27, 26, 25, 48, 47, 46, 44, 43, 41, 40, 39,
    37, 36, 35, 34, 32, 31, 30, 28, 27, 26, 24, 23, 22, 20, 19, 37,
    35, 34, 33, 31, 30, 29, 27, 26, 24, 23, 21, 20, 18, 17, 15, 29,
    27, 26, 24, 22, 21, 19, 17, 16, 14, 26, 25, 23, 21, 19, 18, 16,
    15, 27, 25, 23, 21, 19, 17, 16, 14, 26, 25, 23, 21, 18, 17, 14,
    12, 17, 19, 13,  4,  9,  2, 11,  1,  7,  8,  0, 16,  3, 14,  6,
    12, 10,  5, 15, 18, 11, 10, 13, 15, 16, 19, 20, 22, 24, 27, 15,
    18, 20, 22, 24, 26, 14, 17, 20, 22, 24, 27, 15, 18, 20, 23, 25,
    28, 16, 19, 22, 25, 28, 32, 36, 21, 25, 29, 33, 38, 42, 45, 49,
    28, 31, 34, 37, 40, 42, 44, 47, 49, 50, 52, 54, 56, 57, 59, 60,
    62, 64, 66, 67, 69, 35, 37, 39, 40, 42, 43, 45, 47, 48, 51, 52,
    54, 55, 57, 59, 60, 62, 63, 66, 67, 69, 71, 72, 38, 40, 42, 43,
    46, 47, 49, 51, 26, 28, 30, 31, 33, 34, 18, 19, 11, 13,  7,  8,
 };
 
 static const unsigned char classic_add_chroma[256] = {
     3,  1,  2,  2,  2,  2,  3,  3,  7,  5,  7,  5,  8,  6, 11,  9,
     7, 13, 11, 10,  9,  8,  7,  5,  9,  7,  6,  4,  7,  5,  8,  7,
    11,  8, 13, 11, 19, 15, 22, 23, 20, 33, 32, 28, 27, 29, 51, 77,
    43, 45, 76, 81, 46, 82, 75, 55, 56,144, 58, 80, 60, 74,147, 63,
   143, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
    80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 27, 30, 21, 22,
    17, 14,  5,  6,100, 54, 47, 50, 51, 53,106,107,108,109,110,111,
   112,113,114,115,  4,117,118, 92, 94,121,122,  3,124,103,  2,  1,
     0,129,130,131,120,119,126,125,136,137,138,139,140,141,142,134,
   135,132,133,104, 64,101, 62, 57,102, 95, 93, 59, 61, 28, 97, 96,
    52, 49, 48, 29, 32, 25, 24, 46, 23, 98, 45, 44, 43, 20, 42, 41,
    19, 18, 99, 40, 15, 39, 38, 16, 13, 12, 11, 37, 10,  9,  8, 36,
     7,128,127,105,123,116, 35, 34, 33,145, 31, 79, 42,146, 78, 26,
    83, 48, 49, 50, 44, 47, 26, 31, 30, 18, 17, 19, 21, 24, 25, 13,
    14, 16, 17, 18, 20, 21, 12, 14, 15,  9, 10,  6,  9,  6,  5,  8,
     6, 12,  8, 10,  7,  9,  6,  4,  6,  2,  2,  3,  3,  3,  3,  2,
 };
 
 static int read_len_table(uint8_t *dst, GetBitContext *gb)
 {
     int i, val, repeat;
 
     for (i = 0; i < 256;) {
         repeat = get_bits(gb, 3);
         val    = get_bits(gb, 5);
         if (repeat == 0)
             repeat = get_bits(gb, 8);
         if (i + repeat > 256 || get_bits_left(gb) < 0) {
             av_log(NULL, AV_LOG_ERROR, "Error reading huffman table\n");
             return -1;
         }
         while (repeat--)
             dst[i++] = val;
     }
     return 0;
 }
 
 static void generate_joint_tables(HYuvContext *s)
 {
     uint16_t symbols[1 << VLC_BITS];
     uint16_t bits[1 << VLC_BITS];
     uint8_t len[1 << VLC_BITS];
     if (s->bitstream_bpp < 24) {
         int p, i, y, u;
         for (p = 0; p < 3; p++) {
             for (i = y = 0; y < 256; y++) {
                 int len0 = s->len[0][y];
                 int limit = VLC_BITS - len0;

                 if(limit <= 0 || !len0)

                     continue;
                 for (u = 0; u < 256; u++) {
                     int len1 = s->len[p][u];

                     if (len1 > limit || !len1)

                         continue;

                     av_assert0(i < (1 << VLC_BITS));

                     len[i] = len0 + len1;
                     bits[i] = (s->bits[0][y] << len1) + s->bits[p][u];
                     symbols[i] = (y << 8) + u;
                     if(symbols[i] != 0xffff) // reserved to mean "invalid"
                         i++;
                 }
             }
             ff_free_vlc(&s->vlc[3 + p]);
             ff_init_vlc_sparse(&s->vlc[3 + p], VLC_BITS, i, len, 1, 1,
                                bits, 2, 2, symbols, 2, 2, 0);
         }
     } else {
         uint8_t (*map)[4] = (uint8_t(*)[4])s->pix_bgr_map;
         int i, b, g, r, code;
         int p0 = s->decorrelate;
         int p1 = !s->decorrelate;
         // restrict the range to +/-16 because that's pretty much guaranteed to
         // cover all the combinations that fit in 11 bits total, and it doesn't
         // matter if we miss a few rare codes.
         for (i = 0, g = -16; g < 16; g++) {
             int len0 = s->len[p0][g & 255];
             int limit0 = VLC_BITS - len0;

             if (limit0 < 2 || !len0)

                 continue;
             for (b = -16; b < 16; b++) {
                 int len1 = s->len[p1][b & 255];
                 int limit1 = limit0 - len1;

                 if (limit1 < 1 || !len1)

                     continue;
                 code = (s->bits[p0][g & 255] << len1) + s->bits[p1][b & 255];
                 for (r = -16; r < 16; r++) {
                     int len2 = s->len[2][r & 255];

                     if (len2 > limit1 || !len2)

                         continue;

                     av_assert0(i < (1 << VLC_BITS));

                     len[i] = len0 + len1 + len2;
                     bits[i] = (code << len2) + s->bits[2][r & 255];
                     if (s->decorrelate) {
                         map[i][G] = g;
                         map[i][B] = g + b;
                         map[i][R] = g + r;
                     } else {
                         map[i][B] = g;
                         map[i][G] = b;
                         map[i][R] = r;
                     }
                     i++;
                 }
             }
         }
         ff_free_vlc(&s->vlc[3]);
         init_vlc(&s->vlc[3], VLC_BITS, i, len, 1, 1, bits, 2, 2, 0);
     }
 }
 
 static int read_huffman_tables(HYuvContext *s, const uint8_t *src, int length)
 {
     GetBitContext gb;
     int i;

     int ret;

 
     init_get_bits(&gb, src, length * 8);
 
     for (i = 0; i < 3; i++) {
         if (read_len_table(s->len[i], &gb) < 0)
             return -1;
         if (ff_huffyuv_generate_bits_table(s->bits[i], s->len[i]) < 0) {
             return -1;
         }
         ff_free_vlc(&s->vlc[i]);

         if ((ret = init_vlc(&s->vlc[i], VLC_BITS, 256, s->len[i], 1, 1,
                            s->bits[i], 4, 4, 0)) < 0)
             return ret;

     }
 
     generate_joint_tables(s);
 
     return (get_bits_count(&gb) + 7) / 8;
 }
 
 static int read_old_huffman_tables(HYuvContext *s)
 {
     GetBitContext gb;
     int i;

     int ret;

 
     init_get_bits(&gb, classic_shift_luma,
                   classic_shift_luma_table_size * 8);
     if (read_len_table(s->len[0], &gb) < 0)
         return -1;
 
     init_get_bits(&gb, classic_shift_chroma,
                   classic_shift_chroma_table_size * 8);
     if (read_len_table(s->len[1], &gb) < 0)
         return -1;
 
     for(i=0; i<256; i++) s->bits[0][i] = classic_add_luma  [i];
     for(i=0; i<256; i++) s->bits[1][i] = classic_add_chroma[i];
 
     if (s->bitstream_bpp >= 24) {
         memcpy(s->bits[1], s->bits[0], 256 * sizeof(uint32_t));
         memcpy(s->len[1] , s->len [0], 256 * sizeof(uint8_t));
     }
     memcpy(s->bits[2], s->bits[1], 256 * sizeof(uint32_t));
     memcpy(s->len[2] , s->len [1], 256 * sizeof(uint8_t));
 
     for (i = 0; i < 3; i++) {
         ff_free_vlc(&s->vlc[i]);

         if ((ret = init_vlc(&s->vlc[i], VLC_BITS, 256, s->len[i], 1, 1,
                             s->bits[i], 4, 4, 0)) < 0)
             return ret;

     }
 
     generate_joint_tables(s);
 
     return 0;
 }
 
 static av_cold int decode_init(AVCodecContext *avctx)
 {
     HYuvContext *s = avctx->priv_data;
 
     ff_huffyuv_common_init(avctx);
     memset(s->vlc, 0, 3 * sizeof(VLC));
 
     avctx->coded_frame = &s->picture;

     avcodec_get_frame_defaults(&s->picture);

     s->interlaced = s->height > 288;
 
     s->bgr32 = 1;
 
     if (avctx->extradata_size) {
         if ((avctx->bits_per_coded_sample & 7) &&
             avctx->bits_per_coded_sample != 12)
             s->version = 1; // do such files exist at all?
         else
             s->version = 2;
     } else
         s->version = 0;
 
     if (s->version == 2) {
         int method, interlace;
 
         if (avctx->extradata_size < 4)
             return -1;
 
         method = ((uint8_t*)avctx->extradata)[0];
         s->decorrelate = method & 64 ? 1 : 0;
         s->predictor = method & 63;
         s->bitstream_bpp = ((uint8_t*)avctx->extradata)[1];
         if (s->bitstream_bpp == 0)
             s->bitstream_bpp = avctx->bits_per_coded_sample & ~7;
         interlace = (((uint8_t*)avctx->extradata)[2] & 0x30) >> 4;
         s->interlaced = (interlace == 1) ? 1 : (interlace == 2) ? 0 : s->interlaced;
         s->context = ((uint8_t*)avctx->extradata)[2] & 0x40 ? 1 : 0;
 
         if ( read_huffman_tables(s, ((uint8_t*)avctx->extradata) + 4,
                                  avctx->extradata_size - 4) < 0)

             return AVERROR_INVALIDDATA;

     }else{
         switch (avctx->bits_per_coded_sample & 7) {
         case 1:
             s->predictor = LEFT;
             s->decorrelate = 0;
             break;
         case 2:
             s->predictor = LEFT;
             s->decorrelate = 1;
             break;
         case 3:
             s->predictor = PLANE;
             s->decorrelate = avctx->bits_per_coded_sample >= 24;
             break;
         case 4:
             s->predictor = MEDIAN;
             s->decorrelate = 0;
             break;
         default:
             s->predictor = LEFT; //OLD
             s->decorrelate = 0;
             break;
         }
         s->bitstream_bpp = avctx->bits_per_coded_sample & ~7;
         s->context = 0;
 
         if (read_old_huffman_tables(s) < 0)

             return AVERROR_INVALIDDATA;

     }
 
     switch (s->bitstream_bpp) {
     case 12:
         avctx->pix_fmt = AV_PIX_FMT_YUV420P;
         break;
     case 16:
         if (s->yuy2) {
             avctx->pix_fmt = AV_PIX_FMT_YUYV422;
         } else {
             avctx->pix_fmt = AV_PIX_FMT_YUV422P;
         }
         break;
     case 24:
     case 32:
         if (s->bgr32) {
             avctx->pix_fmt = AV_PIX_FMT_RGB32;
         } else {
             avctx->pix_fmt = AV_PIX_FMT_BGR24;
         }
         break;
     default:
         return AVERROR_INVALIDDATA;
     }
 

     if ((avctx->pix_fmt == AV_PIX_FMT_YUV422P || avctx->pix_fmt == AV_PIX_FMT_YUV420P) && avctx->width & 1) {
         av_log(avctx, AV_LOG_ERROR, "width must be even for this colorspace\n");
         return AVERROR_INVALIDDATA;
     }
     if (s->predictor == MEDIAN && avctx->pix_fmt == AV_PIX_FMT_YUV422P && avctx->width%4) {
         av_log(avctx, AV_LOG_ERROR, "width must be a multiple of 4 this colorspace and predictor\n");
         return AVERROR_INVALIDDATA;
     }
     if (ff_huffyuv_alloc_temp(s)) {
         ff_huffyuv_common_end(s);
         return AVERROR(ENOMEM);
     }

 
     return 0;
 }
 
 static av_cold int decode_init_thread_copy(AVCodecContext *avctx)
 {
     HYuvContext *s = avctx->priv_data;
     int i;
 
     avctx->coded_frame= &s->picture;

     if (ff_huffyuv_alloc_temp(s)) {
         ff_huffyuv_common_end(s);
         return AVERROR(ENOMEM);
     }

 
     for (i = 0; i < 6; i++)
         s->vlc[i].table = NULL;
 
     if (s->version == 2) {
         if (read_huffman_tables(s, ((uint8_t*)avctx->extradata) + 4,
                                 avctx->extradata_size) < 0)

             return AVERROR_INVALIDDATA;

     } else {
         if (read_old_huffman_tables(s) < 0)

             return AVERROR_INVALIDDATA;

     }
 
     return 0;
 }
 
 /* TODO instead of restarting the read when the code isn't in the first level
  * of the joint table, jump into the 2nd level of the individual table. */
 #define READ_2PIX(dst0, dst1, plane1){\
     uint16_t code = get_vlc2(&s->gb, s->vlc[3+plane1].table, VLC_BITS, 1);\
     if(code != 0xffff){\
         dst0 = code>>8;\
         dst1 = code;\
     }else{\
         dst0 = get_vlc2(&s->gb, s->vlc[0].table, VLC_BITS, 3);\
         dst1 = get_vlc2(&s->gb, s->vlc[plane1].table, VLC_BITS, 3);\
     }\
 }
 
 static void decode_422_bitstream(HYuvContext *s, int count)
 {
     int i;
 
     count /= 2;
 
     if (count >= (get_bits_left(&s->gb)) / (31 * 4)) {
         for (i = 0; i < count && get_bits_left(&s->gb) > 0; i++) {
             READ_2PIX(s->temp[0][2 * i    ], s->temp[1][i], 1);
             READ_2PIX(s->temp[0][2 * i + 1], s->temp[2][i], 2);
         }
     } else {
         for (i = 0; i < count; i++) {
             READ_2PIX(s->temp[0][2 * i    ], s->temp[1][i], 1);
             READ_2PIX(s->temp[0][2 * i + 1], s->temp[2][i], 2);
         }
     }
 }
 
 static void decode_gray_bitstream(HYuvContext *s, int count)
 {
     int i;
 
     count/=2;
 
     if (count >= (get_bits_left(&s->gb)) / (31 * 2)) {
         for (i = 0; i < count && get_bits_left(&s->gb) > 0; i++) {
             READ_2PIX(s->temp[0][2 * i], s->temp[0][2 * i + 1], 0);
         }
     } else {
         for(i=0; i<count; i++){
             READ_2PIX(s->temp[0][2 * i], s->temp[0][2 * i + 1], 0);
         }
     }
 }
 
 static av_always_inline void decode_bgr_1(HYuvContext *s, int count,
                                           int decorrelate, int alpha)
 {
     int i;
     for (i = 0; i < count; i++) {
         int code = get_vlc2(&s->gb, s->vlc[3].table, VLC_BITS, 1);
         if (code != -1) {
             *(uint32_t*)&s->temp[0][4 * i] = s->pix_bgr_map[code];
         } else if(decorrelate) {
             s->temp[0][4 * i + G] = get_vlc2(&s->gb, s->vlc[1].table, VLC_BITS, 3);
             s->temp[0][4 * i + B] = get_vlc2(&s->gb, s->vlc[0].table, VLC_BITS, 3) +
                                     s->temp[0][4 * i + G];
             s->temp[0][4 * i + R] = get_vlc2(&s->gb, s->vlc[2].table, VLC_BITS, 3) +
                                     s->temp[0][4 * i + G];
         } else {
             s->temp[0][4 * i + B] = get_vlc2(&s->gb, s->vlc[0].table, VLC_BITS, 3);
             s->temp[0][4 * i + G] = get_vlc2(&s->gb, s->vlc[1].table, VLC_BITS, 3);
             s->temp[0][4 * i + R] = get_vlc2(&s->gb, s->vlc[2].table, VLC_BITS, 3);
         }
         if (alpha)
             s->temp[0][4 * i + A] = get_vlc2(&s->gb, s->vlc[2].table, VLC_BITS, 3);
     }
 }
 
 static void decode_bgr_bitstream(HYuvContext *s, int count)
 {
     if (s->decorrelate) {
         if (s->bitstream_bpp==24)
             decode_bgr_1(s, count, 1, 0);
         else
             decode_bgr_1(s, count, 1, 1);
     } else {
         if (s->bitstream_bpp==24)
             decode_bgr_1(s, count, 0, 0);
         else
             decode_bgr_1(s, count, 0, 1);
     }
 }
 
 static void draw_slice(HYuvContext *s, int y)
 {
     int h, cy, i;
     int offset[AV_NUM_DATA_POINTERS];
 
     if (s->avctx->draw_horiz_band==NULL)
         return;
 
     h = y - s->last_slice_end;
     y -= h;
 
     if (s->bitstream_bpp == 12) {
         cy = y>>1;
     } else {
         cy = y;
     }
 
     offset[0] = s->picture.linesize[0]*y;
     offset[1] = s->picture.linesize[1]*cy;
     offset[2] = s->picture.linesize[2]*cy;
     for (i = 3; i < AV_NUM_DATA_POINTERS; i++)
         offset[i] = 0;
     emms_c();
 
     s->avctx->draw_horiz_band(s->avctx, &s->picture, offset, y, 3, h);
 
     s->last_slice_end = y + h;
 }
 
 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
                         AVPacket *avpkt)
 {
     const uint8_t *buf = avpkt->data;
     int buf_size = avpkt->size;
     HYuvContext *s = avctx->priv_data;
     const int width = s->width;
     const int width2 = s->width>>1;
     const int height = s->height;
     int fake_ystride, fake_ustride, fake_vstride;
     AVFrame * const p = &s->picture;

     int table_size = 0, ret;

 
     AVFrame *picture = data;
 

     av_fast_padded_malloc(&s->bitstream_buffer,

                    &s->bitstream_buffer_size,

                    buf_size);

     if (!s->bitstream_buffer)
         return AVERROR(ENOMEM);
 
     s->dsp.bswap_buf((uint32_t*)s->bitstream_buffer,
                      (const uint32_t*)buf, buf_size / 4);
 
     if (p->data[0])
         ff_thread_release_buffer(avctx, p);
 
     p->reference = 0;

     if ((ret = ff_thread_get_buffer(avctx, p)) < 0) {

         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

         return ret;

     }
 
     if (s->context) {
         table_size = read_huffman_tables(s, s->bitstream_buffer, buf_size);
         if (table_size < 0)

             return AVERROR_INVALIDDATA;

     }
 
     if ((unsigned)(buf_size-table_size) >= INT_MAX / 8)

         return AVERROR_INVALIDDATA;

 
     init_get_bits(&s->gb, s->bitstream_buffer+table_size,
                   (buf_size-table_size) * 8);
 
     fake_ystride = s->interlaced ? p->linesize[0] * 2  : p->linesize[0];
     fake_ustride = s->interlaced ? p->linesize[1] * 2  : p->linesize[1];
     fake_vstride = s->interlaced ? p->linesize[2] * 2  : p->linesize[2];
 
     s->last_slice_end = 0;
 
     if (s->bitstream_bpp < 24) {
         int y, cy;
         int lefty, leftu, leftv;
         int lefttopy, lefttopu, lefttopv;
 
         if (s->yuy2) {
             p->data[0][3] = get_bits(&s->gb, 8);
             p->data[0][2] = get_bits(&s->gb, 8);
             p->data[0][1] = get_bits(&s->gb, 8);
             p->data[0][0] = get_bits(&s->gb, 8);
 
             av_log(avctx, AV_LOG_ERROR,
                    "YUY2 output is not implemented yet\n");

             return AVERROR_PATCHWELCOME;

         } else {
 
             leftv = p->data[2][0] = get_bits(&s->gb, 8);
             lefty = p->data[0][1] = get_bits(&s->gb, 8);
             leftu = p->data[1][0] = get_bits(&s->gb, 8);
                     p->data[0][0] = get_bits(&s->gb, 8);
 
             switch (s->predictor) {
             case LEFT:
             case PLANE:
                 decode_422_bitstream(s, width-2);
                 lefty = s->dsp.add_hfyu_left_prediction(p->data[0] + 2, s->temp[0], width-2, lefty);
                 if (!(s->flags&CODEC_FLAG_GRAY)) {
                     leftu = s->dsp.add_hfyu_left_prediction(p->data[1] + 1, s->temp[1], width2 - 1, leftu);
                     leftv = s->dsp.add_hfyu_left_prediction(p->data[2] + 1, s->temp[2], width2 - 1, leftv);
                 }
 
                 for (cy = y = 1; y < s->height; y++, cy++) {
                     uint8_t *ydst, *udst, *vdst;
 
                     if (s->bitstream_bpp == 12) {
                         decode_gray_bitstream(s, width);
 
                         ydst = p->data[0] + p->linesize[0] * y;
 
                         lefty = s->dsp.add_hfyu_left_prediction(ydst, s->temp[0], width, lefty);
                         if (s->predictor == PLANE) {
                             if (y > s->interlaced)
                                 s->dsp.add_bytes(ydst, ydst - fake_ystride, width);
                         }
                         y++;
                         if (y >= s->height) break;
                     }
 
                     draw_slice(s, y);
 
                     ydst = p->data[0] + p->linesize[0]*y;
                     udst = p->data[1] + p->linesize[1]*cy;
                     vdst = p->data[2] + p->linesize[2]*cy;
 
                     decode_422_bitstream(s, width);
                     lefty = s->dsp.add_hfyu_left_prediction(ydst, s->temp[0], width, lefty);
                     if (!(s->flags & CODEC_FLAG_GRAY)) {
                         leftu= s->dsp.add_hfyu_left_prediction(udst, s->temp[1], width2, leftu);
                         leftv= s->dsp.add_hfyu_left_prediction(vdst, s->temp[2], width2, leftv);
                     }
                     if (s->predictor == PLANE) {
                         if (cy > s->interlaced) {
                             s->dsp.add_bytes(ydst, ydst - fake_ystride, width);
                             if (!(s->flags & CODEC_FLAG_GRAY)) {
                                 s->dsp.add_bytes(udst, udst - fake_ustride, width2);
                                 s->dsp.add_bytes(vdst, vdst - fake_vstride, width2);
                             }
                         }
                     }
                 }
                 draw_slice(s, height);
 
                 break;
             case MEDIAN:
                 /* first line except first 2 pixels is left predicted */
                 decode_422_bitstream(s, width - 2);
                 lefty= s->dsp.add_hfyu_left_prediction(p->data[0] + 2, s->temp[0], width - 2, lefty);
                 if (!(s->flags & CODEC_FLAG_GRAY)) {
                     leftu = s->dsp.add_hfyu_left_prediction(p->data[1] + 1, s->temp[1], width2 - 1, leftu);
                     leftv = s->dsp.add_hfyu_left_prediction(p->data[2] + 1, s->temp[2], width2 - 1, leftv);
                 }
 
                 cy = y = 1;
 
                 /* second line is left predicted for interlaced case */
                 if (s->interlaced) {
                     decode_422_bitstream(s, width);
                     lefty = s->dsp.add_hfyu_left_prediction(p->data[0] + p->linesize[0], s->temp[0], width, lefty);
                     if (!(s->flags & CODEC_FLAG_GRAY)) {
                         leftu = s->dsp.add_hfyu_left_prediction(p->data[1] + p->linesize[2], s->temp[1], width2, leftu);
                         leftv = s->dsp.add_hfyu_left_prediction(p->data[2] + p->linesize[1], s->temp[2], width2, leftv);
                     }
                     y++; cy++;
                 }
 
                 /* next 4 pixels are left predicted too */
                 decode_422_bitstream(s, 4);
                 lefty = s->dsp.add_hfyu_left_prediction(p->data[0] + fake_ystride, s->temp[0], 4, lefty);
                 if (!(s->flags&CODEC_FLAG_GRAY)) {
                     leftu = s->dsp.add_hfyu_left_prediction(p->data[1] + fake_ustride, s->temp[1], 2, leftu);
                     leftv = s->dsp.add_hfyu_left_prediction(p->data[2] + fake_vstride, s->temp[2], 2, leftv);
                 }
 
                 /* next line except the first 4 pixels is median predicted */
                 lefttopy = p->data[0][3];
                 decode_422_bitstream(s, width - 4);
                 s->dsp.add_hfyu_median_prediction(p->data[0] + fake_ystride+4, p->data[0]+4, s->temp[0], width-4, &lefty, &lefttopy);
                 if (!(s->flags&CODEC_FLAG_GRAY)) {
                     lefttopu = p->data[1][1];
                     lefttopv = p->data[2][1];
                     s->dsp.add_hfyu_median_prediction(p->data[1] + fake_ustride+2, p->data[1] + 2, s->temp[1], width2 - 2, &leftu, &lefttopu);
                     s->dsp.add_hfyu_median_prediction(p->data[2] + fake_vstride+2, p->data[2] + 2, s->temp[2], width2 - 2, &leftv, &lefttopv);
                 }
                 y++; cy++;
 
                 for (; y<height; y++, cy++) {
                     uint8_t *ydst, *udst, *vdst;
 
                     if (s->bitstream_bpp == 12) {
                         while (2 * cy > y) {
                             decode_gray_bitstream(s, width);
                             ydst = p->data[0] + p->linesize[0] * y;
                             s->dsp.add_hfyu_median_prediction(ydst, ydst - fake_ystride, s->temp[0], width, &lefty, &lefttopy);
                             y++;
                         }
                         if (y >= height) break;
                     }
                     draw_slice(s, y);
 
                     decode_422_bitstream(s, width);
 
                     ydst = p->data[0] + p->linesize[0] * y;
                     udst = p->data[1] + p->linesize[1] * cy;
                     vdst = p->data[2] + p->linesize[2] * cy;
 
                     s->dsp.add_hfyu_median_prediction(ydst, ydst - fake_ystride, s->temp[0], width, &lefty, &lefttopy);
                     if (!(s->flags & CODEC_FLAG_GRAY)) {
                         s->dsp.add_hfyu_median_prediction(udst, udst - fake_ustride, s->temp[1], width2, &leftu, &lefttopu);
                         s->dsp.add_hfyu_median_prediction(vdst, vdst - fake_vstride, s->temp[2], width2, &leftv, &lefttopv);
                     }
                 }
 
                 draw_slice(s, height);
                 break;
             }
         }
     } else {
         int y;
         int leftr, leftg, leftb, lefta;
         const int last_line = (height - 1) * p->linesize[0];
 
         if (s->bitstream_bpp == 32) {
             lefta = p->data[0][last_line+A] = get_bits(&s->gb, 8);
             leftr = p->data[0][last_line+R] = get_bits(&s->gb, 8);
             leftg = p->data[0][last_line+G] = get_bits(&s->gb, 8);
             leftb = p->data[0][last_line+B] = get_bits(&s->gb, 8);
         } else {
             leftr = p->data[0][last_line+R] = get_bits(&s->gb, 8);
             leftg = p->data[0][last_line+G] = get_bits(&s->gb, 8);
             leftb = p->data[0][last_line+B] = get_bits(&s->gb, 8);
             lefta = p->data[0][last_line+A] = 255;
             skip_bits(&s->gb, 8);
         }
 
         if (s->bgr32) {
             switch (s->predictor) {
             case LEFT:
             case PLANE:
                 decode_bgr_bitstream(s, width - 1);
                 s->dsp.add_hfyu_left_prediction_bgr32(p->data[0] + last_line+4, s->temp[0], width - 1, &leftr, &leftg, &leftb, &lefta);
 
                 for (y = s->height - 2; y >= 0; y--) { //Yes it is stored upside down.
                     decode_bgr_bitstream(s, width);
 
                     s->dsp.add_hfyu_left_prediction_bgr32(p->data[0] + p->linesize[0]*y, s->temp[0], width, &leftr, &leftg, &leftb, &lefta);
                     if (s->predictor == PLANE) {
                         if (s->bitstream_bpp != 32) lefta = 0;
                         if ((y & s->interlaced) == 0 &&
                             y < s->height - 1 - s->interlaced) {
                             s->dsp.add_bytes(p->data[0] + p->linesize[0] * y,
                                              p->data[0] + p->linesize[0] * y +
                                              fake_ystride, fake_ystride);
                         }
                     }
                 }
                 // just 1 large slice as this is not possible in reverse order
                 draw_slice(s, height);
                 break;
             default:
                 av_log(avctx, AV_LOG_ERROR,
                        "prediction type not supported!\n");
             }
         }else{
             av_log(avctx, AV_LOG_ERROR,
                    "BGR24 output is not implemented yet\n");

             return AVERROR_PATCHWELCOME;

         }
     }
     emms_c();
 
     *picture = *p;
     *got_frame = 1;
 
     return (get_bits_count(&s->gb) + 31) / 32 * 4 + table_size;
 }
 
 static av_cold int decode_end(AVCodecContext *avctx)
 {
     HYuvContext *s = avctx->priv_data;
     int i;
 
     if (s->picture.data[0])
         avctx->release_buffer(avctx, &s->picture);
 
     ff_huffyuv_common_end(s);
     av_freep(&s->bitstream_buffer);
 
     for (i = 0; i < 6; i++) {
         ff_free_vlc(&s->vlc[i]);
     }
 
     return 0;
 }
 
 #if CONFIG_HUFFYUV_DECODER
 AVCodec ff_huffyuv_decoder = {
     .name             = "huffyuv",
     .type             = AVMEDIA_TYPE_VIDEO,
     .id               = AV_CODEC_ID_HUFFYUV,
     .priv_data_size   = sizeof(HYuvContext),
     .init             = decode_init,
     .close            = decode_end,
     .decode           = decode_frame,
     .capabilities     = CODEC_CAP_DR1 | CODEC_CAP_DRAW_HORIZ_BAND |
                         CODEC_CAP_FRAME_THREADS,
     .init_thread_copy = ONLY_IF_THREADS_ENABLED(decode_init_thread_copy),
     .long_name        = NULL_IF_CONFIG_SMALL("Huffyuv / HuffYUV"),
 };
 #endif
 
 #if CONFIG_FFVHUFF_DECODER
 AVCodec ff_ffvhuff_decoder = {
     .name             = "ffvhuff",
     .type             = AVMEDIA_TYPE_VIDEO,
     .id               = AV_CODEC_ID_FFVHUFF,
     .priv_data_size   = sizeof(HYuvContext),
     .init             = decode_init,
     .close            = decode_end,
     .decode           = decode_frame,
     .capabilities     = CODEC_CAP_DR1 | CODEC_CAP_DRAW_HORIZ_BAND |
                         CODEC_CAP_FRAME_THREADS,
     .init_thread_copy = ONLY_IF_THREADS_ENABLED(decode_init_thread_copy),
     .long_name        = NULL_IF_CONFIG_SMALL("Huffyuv FFmpeg variant"),
 };
 #endif