/*
  * The simplest mpeg encoder (well, it was the simplest!)

  * Copyright (c) 2000,2001 Fabrice Bellard

  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>

  *

  * 4MV & hq & B-frame encoding stuff by Michael Niedermayer <michaelni@gmx.at>
  *

  * 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

  * The simplest mpeg encoder (well, it was the simplest!).

  */
 

 #include "libavutil/attributes.h"

 #include "libavutil/avassert.h"

 #include "libavutil/imgutils.h"

 #include "libavutil/internal.h"

 #include "libavutil/motion_vector.h"

 #include "libavutil/timer.h"

 #include "avcodec.h"

 #include "blockdsp.h"

 #include "h264chroma.h"

 #include "idctdsp.h"

 #include "internal.h"

 #include "mathops.h"

 #include "mpeg_er.h"

 #include "mpegutils.h"

 #include "mpegvideo.h"

 #include "mpegvideodata.h"

 #include "mjpegenc.h"

 #include "msmpeg4.h"

 #include "qpeldsp.h"

 #include "thread.h"

 #include "wmv2.h"

 #include <limits.h>

 static void dct_unquantize_mpeg1_intra_c(MpegEncContext *s,
                                    int16_t *block, int n, int qscale)
 {
     int i, level, nCoeffs;
     const uint16_t *quant_matrix;
 
     nCoeffs= s->block_last_index[n];
 

     block[0] *= n < 4 ? s->y_dc_scale : s->c_dc_scale;

     /* XXX: only MPEG-1 */

     quant_matrix = s->intra_matrix;
     for(i=1;i<=nCoeffs;i++) {
         int j= s->intra_scantable.permutated[i];
         level = block[j];
         if (level) {
             if (level < 0) {
                 level = -level;
                 level = (int)(level * qscale * quant_matrix[j]) >> 3;
                 level = (level - 1) | 1;
                 level = -level;
             } else {
                 level = (int)(level * qscale * quant_matrix[j]) >> 3;
                 level = (level - 1) | 1;
             }
             block[j] = level;
         }
     }
 }
 
 static void dct_unquantize_mpeg1_inter_c(MpegEncContext *s,
                                    int16_t *block, int n, int qscale)
 {
     int i, level, nCoeffs;
     const uint16_t *quant_matrix;
 
     nCoeffs= s->block_last_index[n];
 
     quant_matrix = s->inter_matrix;
     for(i=0; i<=nCoeffs; i++) {
         int j= s->intra_scantable.permutated[i];
         level = block[j];
         if (level) {
             if (level < 0) {
                 level = -level;
                 level = (((level << 1) + 1) * qscale *
                          ((int) (quant_matrix[j]))) >> 4;
                 level = (level - 1) | 1;
                 level = -level;
             } else {
                 level = (((level << 1) + 1) * qscale *
                          ((int) (quant_matrix[j]))) >> 4;
                 level = (level - 1) | 1;
             }
             block[j] = level;
         }
     }
 }
 
 static void dct_unquantize_mpeg2_intra_c(MpegEncContext *s,
                                    int16_t *block, int n, int qscale)
 {
     int i, level, nCoeffs;
     const uint16_t *quant_matrix;
 

     if (s->q_scale_type) qscale = ff_mpeg2_non_linear_qscale[qscale];
     else                 qscale <<= 1;

     if(s->alternate_scan) nCoeffs= 63;
     else nCoeffs= s->block_last_index[n];
 

     block[0] *= n < 4 ? s->y_dc_scale : s->c_dc_scale;

     quant_matrix = s->intra_matrix;
     for(i=1;i<=nCoeffs;i++) {
         int j= s->intra_scantable.permutated[i];
         level = block[j];
         if (level) {
             if (level < 0) {
                 level = -level;

                 level = (int)(level * qscale * quant_matrix[j]) >> 4;

                 level = -level;
             } else {

                 level = (int)(level * qscale * quant_matrix[j]) >> 4;

             }
             block[j] = level;
         }
     }
 }
 
 static void dct_unquantize_mpeg2_intra_bitexact(MpegEncContext *s,
                                    int16_t *block, int n, int qscale)
 {
     int i, level, nCoeffs;
     const uint16_t *quant_matrix;
     int sum=-1;
 

     if (s->q_scale_type) qscale = ff_mpeg2_non_linear_qscale[qscale];
     else                 qscale <<= 1;

     if(s->alternate_scan) nCoeffs= 63;
     else nCoeffs= s->block_last_index[n];
 

     block[0] *= n < 4 ? s->y_dc_scale : s->c_dc_scale;
     sum += block[0];

     quant_matrix = s->intra_matrix;
     for(i=1;i<=nCoeffs;i++) {
         int j= s->intra_scantable.permutated[i];
         level = block[j];
         if (level) {
             if (level < 0) {
                 level = -level;

                 level = (int)(level * qscale * quant_matrix[j]) >> 4;

                 level = -level;
             } else {

                 level = (int)(level * qscale * quant_matrix[j]) >> 4;

             }
             block[j] = level;
             sum+=level;
         }
     }
     block[63]^=sum&1;
 }
 
 static void dct_unquantize_mpeg2_inter_c(MpegEncContext *s,
                                    int16_t *block, int n, int qscale)
 {
     int i, level, nCoeffs;
     const uint16_t *quant_matrix;
     int sum=-1;
 

     if (s->q_scale_type) qscale = ff_mpeg2_non_linear_qscale[qscale];
     else                 qscale <<= 1;

     if(s->alternate_scan) nCoeffs= 63;
     else nCoeffs= s->block_last_index[n];
 
     quant_matrix = s->inter_matrix;
     for(i=0; i<=nCoeffs; i++) {
         int j= s->intra_scantable.permutated[i];
         level = block[j];
         if (level) {
             if (level < 0) {
                 level = -level;
                 level = (((level << 1) + 1) * qscale *

                          ((int) (quant_matrix[j]))) >> 5;

                 level = -level;
             } else {
                 level = (((level << 1) + 1) * qscale *

                          ((int) (quant_matrix[j]))) >> 5;

             }
             block[j] = level;
             sum+=level;
         }
     }
     block[63]^=sum&1;
 }
 
 static void dct_unquantize_h263_intra_c(MpegEncContext *s,
                                   int16_t *block, int n, int qscale)
 {
     int i, level, qmul, qadd;
     int nCoeffs;
 

     av_assert2(s->block_last_index[n]>=0 || s->h263_aic);

 
     qmul = qscale << 1;
 
     if (!s->h263_aic) {

         block[0] *= n < 4 ? s->y_dc_scale : s->c_dc_scale;

         qadd = (qscale - 1) | 1;
     }else{
         qadd = 0;
     }
     if(s->ac_pred)
         nCoeffs=63;
     else

         nCoeffs= s->intra_scantable.raster_end[ s->block_last_index[n] ];

 
     for(i=1; i<=nCoeffs; i++) {
         level = block[i];
         if (level) {
             if (level < 0) {
                 level = level * qmul - qadd;
             } else {
                 level = level * qmul + qadd;
             }
             block[i] = level;
         }
     }
 }
 
 static void dct_unquantize_h263_inter_c(MpegEncContext *s,
                                   int16_t *block, int n, int qscale)
 {
     int i, level, qmul, qadd;
     int nCoeffs;
 

     av_assert2(s->block_last_index[n]>=0);

 
     qadd = (qscale - 1) | 1;
     qmul = qscale << 1;
 
     nCoeffs= s->inter_scantable.raster_end[ s->block_last_index[n] ];
 
     for(i=0; i<=nCoeffs; i++) {
         level = block[i];
         if (level) {
             if (level < 0) {
                 level = level * qmul - qadd;
             } else {
                 level = level * qmul + qadd;
             }
             block[i] = level;
         }
     }
 }
 

 static void gray16(uint8_t *dst, const uint8_t *src, ptrdiff_t linesize, int h)

 {
     while(h--)
         memset(dst + h*linesize, 128, 16);
 }
 

 static void gray8(uint8_t *dst, const uint8_t *src, ptrdiff_t linesize, int h)

 {
     while(h--)
         memset(dst + h*linesize, 128, 8);
 }
 

 /* init common dct for both encoder and decoder */

 static av_cold int dct_init(MpegEncContext *s)

 {

     ff_blockdsp_init(&s->bdsp, s->avctx);

     ff_h264chroma_init(&s->h264chroma, 8); //for lowres

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

     ff_mpegvideodsp_init(&s->mdsp);

     ff_videodsp_init(&s->vdsp, s->avctx->bits_per_raw_sample);

     if (s->avctx->debug & FF_DEBUG_NOMC) {
         int i;
         for (i=0; i<4; i++) {
             s->hdsp.avg_pixels_tab[0][i] = gray16;
             s->hdsp.put_pixels_tab[0][i] = gray16;
             s->hdsp.put_no_rnd_pixels_tab[0][i] = gray16;
 
             s->hdsp.avg_pixels_tab[1][i] = gray8;
             s->hdsp.put_pixels_tab[1][i] = gray8;
             s->hdsp.put_no_rnd_pixels_tab[1][i] = gray8;
         }
     }
 

     s->dct_unquantize_h263_intra = dct_unquantize_h263_intra_c;
     s->dct_unquantize_h263_inter = dct_unquantize_h263_inter_c;
     s->dct_unquantize_mpeg1_intra = dct_unquantize_mpeg1_intra_c;
     s->dct_unquantize_mpeg1_inter = dct_unquantize_mpeg1_inter_c;
     s->dct_unquantize_mpeg2_intra = dct_unquantize_mpeg2_intra_c;

     if (s->avctx->flags & AV_CODEC_FLAG_BITEXACT)

         s->dct_unquantize_mpeg2_intra = dct_unquantize_mpeg2_intra_bitexact;

     s->dct_unquantize_mpeg2_inter = dct_unquantize_mpeg2_inter_c;

     if (HAVE_INTRINSICS_NEON)

         ff_mpv_common_init_neon(s);

     if (ARCH_ALPHA)

         ff_mpv_common_init_axp(s);

     if (ARCH_ARM)

         ff_mpv_common_init_arm(s);

     if (ARCH_PPC)

         ff_mpv_common_init_ppc(s);

     if (ARCH_X86)

         ff_mpv_common_init_x86(s);

     if (ARCH_MIPS)
         ff_mpv_common_init_mips(s);

     return 0;
 }
 
 av_cold void ff_mpv_idct_init(MpegEncContext *s)
 {

     if (s->codec_id == AV_CODEC_ID_MPEG4)
         s->idsp.mpeg4_studio_profile = s->studio_profile;

     ff_idctdsp_init(&s->idsp, s->avctx);
 

     /* load & permutate scantables

      * note: only wmv uses different ones
      */
     if (s->alternate_scan) {

         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);

     } else {

         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);

     }

     ff_init_scantable(s->idsp.idct_permutation, &s->intra_h_scantable, ff_alternate_horizontal_scan);
     ff_init_scantable(s->idsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);

 }
 

 static int alloc_picture(MpegEncContext *s, Picture *pic, int shared)
 {
     return ff_alloc_picture(s->avctx, pic, &s->me, &s->sc, shared, 0,
                             s->chroma_x_shift, s->chroma_y_shift, s->out_format,

                             s->mb_stride, s->mb_width, s->mb_height, s->b8_stride,

                             &s->linesize, &s->uvlinesize);
 }
 

 static int init_duplicate_context(MpegEncContext *s)

 {

     int y_size = s->b8_stride * (2 * s->mb_height + 1);
     int c_size = s->mb_stride * (s->mb_height + 1);
     int yc_size = y_size + 2 * c_size;

     int i;
 

     if (s->mb_height & 1)
         yc_size += 2*s->b8_stride + 2*s->mb_stride;
 

     s->sc.edge_emu_buffer =

     s->me.scratchpad   =
     s->me.temp         =

     s->sc.rd_scratchpad   =
     s->sc.b_scratchpad    =
     s->sc.obmc_scratchpad = NULL;

     if (s->encoding) {

         FF_ALLOCZ_OR_GOTO(s->avctx, s->me.map,
                           ME_MAP_SIZE * sizeof(uint32_t), fail)
         FF_ALLOCZ_OR_GOTO(s->avctx, s->me.score_map,
                           ME_MAP_SIZE * sizeof(uint32_t), fail)

         if (s->noise_reduction) {

             FF_ALLOCZ_OR_GOTO(s->avctx, s->dct_error_sum,
                               2 * 64 * sizeof(int), fail)

         }

     }

     FF_ALLOCZ_OR_GOTO(s->avctx, s->blocks, 64 * 12 * 2 * sizeof(int16_t), fail)

     s->block = s->blocks[0];

     for (i = 0; i < 12; i++) {

         s->pblocks[i] = &s->block[i];

     }

 
     FF_ALLOCZ_OR_GOTO(s->avctx, s->block32, sizeof(*s->block32), fail)
 

     if (s->avctx->codec_tag == AV_RL32("VCR2")) {
         // exchange uv

         FFSWAP(void *, s->pblocks[4], s->pblocks[5]);

     }

     if (s->out_format == FMT_H263) {
         /* ac values */

         FF_ALLOCZ_OR_GOTO(s->avctx, s->ac_val_base,
                           yc_size * sizeof(int16_t) * 16, fail);

         s->ac_val[0] = s->ac_val_base + s->b8_stride + 1;
         s->ac_val[1] = s->ac_val_base + y_size + s->mb_stride + 1;
         s->ac_val[2] = s->ac_val[1] + c_size;
     }
 

     return 0;
 fail:

     return -1; // free() through ff_mpv_common_end()

 }
 

 static void free_duplicate_context(MpegEncContext *s)
 {

     if (!s)

         return;

     av_freep(&s->sc.edge_emu_buffer);

     av_freep(&s->me.scratchpad);

     s->me.temp =

     s->sc.rd_scratchpad =
     s->sc.b_scratchpad =
     s->sc.obmc_scratchpad = NULL;

     av_freep(&s->dct_error_sum);
     av_freep(&s->me.map);
     av_freep(&s->me.score_map);
     av_freep(&s->blocks);

     av_freep(&s->block32);

     av_freep(&s->ac_val_base);

     s->block = NULL;

 }
 

 static void backup_duplicate_context(MpegEncContext *bak, MpegEncContext *src)
 {
 #define COPY(a) bak->a = src->a

     COPY(sc.edge_emu_buffer);

     COPY(me.scratchpad);

     COPY(me.temp);

     COPY(sc.rd_scratchpad);
     COPY(sc.b_scratchpad);
     COPY(sc.obmc_scratchpad);

     COPY(me.map);
     COPY(me.score_map);
     COPY(blocks);
     COPY(block);

     COPY(block32);

     COPY(start_mb_y);
     COPY(end_mb_y);
     COPY(me.map_generation);
     COPY(pb);
     COPY(dct_error_sum);

     COPY(dct_count[0]);
     COPY(dct_count[1]);

     COPY(ac_val_base);
     COPY(ac_val[0]);
     COPY(ac_val[1]);
     COPY(ac_val[2]);

 #undef COPY
 }
 

 int ff_update_duplicate_context(MpegEncContext *dst, MpegEncContext *src)

 {

     MpegEncContext bak;

     int i, ret;

     // FIXME copy only needed parts
     // START_TIMER

     backup_duplicate_context(&bak, dst);
     memcpy(dst, src, sizeof(MpegEncContext));
     backup_duplicate_context(dst, &bak);

     for (i = 0; i < 12; i++) {

         dst->pblocks[i] = &dst->block[i];

     }

     if (dst->avctx->codec_tag == AV_RL32("VCR2")) {
         // exchange uv

         FFSWAP(void *, dst->pblocks[4], dst->pblocks[5]);

     }

     if (!dst->sc.edge_emu_buffer &&

         (ret = ff_mpeg_framesize_alloc(dst->avctx, &dst->me,
                                        &dst->sc, dst->linesize)) < 0) {

         av_log(dst->avctx, AV_LOG_ERROR, "failed to allocate context "
                "scratch buffers.\n");
         return ret;
     }

     // STOP_TIMER("update_duplicate_context")
     // about 10k cycles / 0.01 sec for  1000frames on 1ghz with 2 threads

     return 0;

 }
 

 int ff_mpeg_update_thread_context(AVCodecContext *dst,
                                   const AVCodecContext *src)

 {

     int i, ret;

     MpegEncContext *s = dst->priv_data, *s1 = src->priv_data;
 

     if (dst == src)

         return 0;

     av_assert0(s != s1);
 

     // FIXME can parameters change on I-frames?
     // in that case dst may need a reinit
     if (!s->context_initialized) {

         int err;

         memcpy(s, s1, sizeof(MpegEncContext));
 
         s->avctx                 = dst;
         s->bitstream_buffer      = NULL;
         s->bitstream_buffer_size = s->allocated_bitstream_buffer_size = 0;
 

         if (s1->context_initialized){

 //             s->picture_range_start  += MAX_PICTURE_COUNT;
 //             s->picture_range_end    += MAX_PICTURE_COUNT;

             ff_mpv_idct_init(s);

             if((err = ff_mpv_common_init(s)) < 0){

                 memset(s, 0, sizeof(MpegEncContext));
                 s->avctx = dst;

                 return err;

             }

         }

     }
 

     if (s->height != s1->height || s->width != s1->width || s->context_reinit) {
         s->context_reinit = 0;
         s->height = s1->height;
         s->width  = s1->width;

         if ((ret = ff_mpv_common_frame_size_change(s)) < 0)

             return ret;

     }
 

     s->avctx->coded_height  = s1->avctx->coded_height;
     s->avctx->coded_width   = s1->avctx->coded_width;
     s->avctx->width         = s1->avctx->width;
     s->avctx->height        = s1->avctx->height;
 
     s->coded_picture_number = s1->coded_picture_number;
     s->picture_number       = s1->picture_number;
 

     av_assert0(!s->picture || s->picture != s1->picture);

     if(s->picture)

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

         ff_mpeg_unref_picture(s->avctx, &s->picture[i]);

         if (s1->picture && s1->picture[i].f->buf[0] &&

             (ret = ff_mpeg_ref_picture(s->avctx, &s->picture[i], &s1->picture[i])) < 0)

             return ret;

     }

 #define UPDATE_PICTURE(pic)\
 do {\

     ff_mpeg_unref_picture(s->avctx, &s->pic);\

     if (s1->pic.f && s1->pic.f->buf[0])\

         ret = ff_mpeg_ref_picture(s->avctx, &s->pic, &s1->pic);\

     else\

         ret = ff_update_picture_tables(&s->pic, &s1->pic);\

     if (ret < 0)\
         return ret;\
 } while (0)
 
     UPDATE_PICTURE(current_picture);
     UPDATE_PICTURE(last_picture);
     UPDATE_PICTURE(next_picture);

 #define REBASE_PICTURE(pic, new_ctx, old_ctx)                                 \
     ((pic && pic >= old_ctx->picture &&                                       \
       pic < old_ctx->picture + MAX_PICTURE_COUNT) ?                           \
         &new_ctx->picture[pic - old_ctx->picture] : NULL)
 

     s->last_picture_ptr    = REBASE_PICTURE(s1->last_picture_ptr,    s, s1);
     s->current_picture_ptr = REBASE_PICTURE(s1->current_picture_ptr, s, s1);
     s->next_picture_ptr    = REBASE_PICTURE(s1->next_picture_ptr,    s, s1);

     // Error/bug resilience

     s->next_p_frame_damaged = s1->next_p_frame_damaged;
     s->workaround_bugs      = s1->workaround_bugs;

     s->padding_bug_score    = s1->padding_bug_score;

     // MPEG-4 timing info

     memcpy(&s->last_time_base, &s1->last_time_base,

            (char *) &s1->pb_field_time + sizeof(s1->pb_field_time) -

            (char *) &s1->last_time_base);

 
     // B-frame info
     s->max_b_frames = s1->max_b_frames;
     s->low_delay    = s1->low_delay;

     s->droppable    = s1->droppable;

 
     // DivX handling (doesn't work)
     s->divx_packed  = s1->divx_packed;
 
     if (s1->bitstream_buffer) {
         if (s1->bitstream_buffer_size +

             AV_INPUT_BUFFER_PADDING_SIZE > s->allocated_bitstream_buffer_size) {

             av_fast_malloc(&s->bitstream_buffer,
                            &s->allocated_bitstream_buffer_size,
                            s1->allocated_bitstream_buffer_size);

             if (!s->bitstream_buffer) {
                 s->bitstream_buffer_size = 0;

                 return AVERROR(ENOMEM);

             }

         }
         s->bitstream_buffer_size = s1->bitstream_buffer_size;

         memcpy(s->bitstream_buffer, s1->bitstream_buffer,
                s1->bitstream_buffer_size);
         memset(s->bitstream_buffer + s->bitstream_buffer_size, 0,

                AV_INPUT_BUFFER_PADDING_SIZE);

     }
 

     // linesize-dependent scratch buffer allocation

     if (!s->sc.edge_emu_buffer)

         if (s1->linesize) {

             if (ff_mpeg_framesize_alloc(s->avctx, &s->me,
                                         &s->sc, s1->linesize) < 0) {

                 av_log(s->avctx, AV_LOG_ERROR, "Failed to allocate context "
                        "scratch buffers.\n");
                 return AVERROR(ENOMEM);
             }
         } else {
             av_log(s->avctx, AV_LOG_ERROR, "Context scratch buffers could not "
                    "be allocated due to unknown size.\n");
         }
 

     // MPEG-2/interlacing info

     memcpy(&s->progressive_sequence, &s1->progressive_sequence,
            (char *) &s1->rtp_mode - (char *) &s1->progressive_sequence);

     if (!s1->first_field) {
         s->last_pict_type = s1->pict_type;
         if (s1->current_picture_ptr)

             s->last_lambda_for[s1->pict_type] = s1->current_picture_ptr->f->quality;

     }
 
     return 0;
 }
 

 /**

  * Set the given MpegEncContext to common defaults

  * (same for encoding and decoding).

  * The changed fields will not depend upon the

  * prior state of the MpegEncContext.

  */

 void ff_mpv_common_defaults(MpegEncContext *s)

 {
     s->y_dc_scale_table      =
     s->c_dc_scale_table      = ff_mpeg1_dc_scale_table;
     s->chroma_qscale_table   = ff_default_chroma_qscale_table;
     s->progressive_frame     = 1;
     s->progressive_sequence  = 1;
     s->picture_structure     = PICT_FRAME;
 
     s->coded_picture_number  = 0;
     s->picture_number        = 0;

     s->f_code                = 1;
     s->b_code                = 1;

     s->slice_context_count   = 1;

 }
 
 /**

  * Set the given MpegEncContext to defaults for decoding.

  * the changed fields will not depend upon
  * the prior state of the MpegEncContext.

  */

 void ff_mpv_decode_defaults(MpegEncContext *s)

 {

     ff_mpv_common_defaults(s);

 }
 

 void ff_mpv_decode_init(MpegEncContext *s, AVCodecContext *avctx)
 {
     s->avctx           = avctx;
     s->width           = avctx->coded_width;
     s->height          = avctx->coded_height;
     s->codec_id        = avctx->codec->id;
     s->workaround_bugs = avctx->workaround_bugs;
 

     /* convert fourcc to upper case */
     s->codec_tag          = avpriv_toupper4(avctx->codec_tag);

 }
 

 /**

  * Initialize and allocates MpegEncContext fields dependent on the resolution.
  */
 static int init_context_frame(MpegEncContext *s)
 {
     int y_size, c_size, yc_size, i, mb_array_size, mv_table_size, x, y;
 
     s->mb_width   = (s->width + 15) / 16;
     s->mb_stride  = s->mb_width + 1;
     s->b8_stride  = s->mb_width * 2 + 1;
     mb_array_size = s->mb_height * s->mb_stride;
     mv_table_size = (s->mb_height + 2) * s->mb_stride + 1;
 

     /* set default edge pos, will be overridden

      * in decode_header if needed */
     s->h_edge_pos = s->mb_width * 16;
     s->v_edge_pos = s->mb_height * 16;
 
     s->mb_num     = s->mb_width * s->mb_height;
 
     s->block_wrap[0] =
     s->block_wrap[1] =
     s->block_wrap[2] =
     s->block_wrap[3] = s->b8_stride;
     s->block_wrap[4] =
     s->block_wrap[5] = s->mb_stride;
 
     y_size  = s->b8_stride * (2 * s->mb_height + 1);
     c_size  = s->mb_stride * (s->mb_height + 1);
     yc_size = y_size + 2   * c_size;
 

     if (s->mb_height & 1)
         yc_size += 2*s->b8_stride + 2*s->mb_stride;
 

     FF_ALLOCZ_OR_GOTO(s->avctx, s->mb_index2xy, (s->mb_num + 1) * sizeof(int),

                       fail); // error resilience code looks cleaner with this

     for (y = 0; y < s->mb_height; y++)
         for (x = 0; x < s->mb_width; x++)
             s->mb_index2xy[x + y * s->mb_width] = x + y * s->mb_stride;
 

     s->mb_index2xy[s->mb_height * s->mb_width] = (s->mb_height - 1) * s->mb_stride + s->mb_width; // FIXME really needed?

 
     if (s->encoding) {
         /* Allocate MV tables */

         FF_ALLOCZ_OR_GOTO(s->avctx, s->p_mv_table_base,                 mv_table_size * 2 * sizeof(int16_t), fail)
         FF_ALLOCZ_OR_GOTO(s->avctx, s->b_forw_mv_table_base,            mv_table_size * 2 * sizeof(int16_t), fail)
         FF_ALLOCZ_OR_GOTO(s->avctx, s->b_back_mv_table_base,            mv_table_size * 2 * sizeof(int16_t), fail)
         FF_ALLOCZ_OR_GOTO(s->avctx, s->b_bidir_forw_mv_table_base,      mv_table_size * 2 * sizeof(int16_t), fail)
         FF_ALLOCZ_OR_GOTO(s->avctx, s->b_bidir_back_mv_table_base,      mv_table_size * 2 * sizeof(int16_t), fail)
         FF_ALLOCZ_OR_GOTO(s->avctx, s->b_direct_mv_table_base,          mv_table_size * 2 * sizeof(int16_t), fail)

         s->p_mv_table            = s->p_mv_table_base + s->mb_stride + 1;
         s->b_forw_mv_table       = s->b_forw_mv_table_base + s->mb_stride + 1;
         s->b_back_mv_table       = s->b_back_mv_table_base + s->mb_stride + 1;

         s->b_bidir_forw_mv_table = s->b_bidir_forw_mv_table_base + s->mb_stride + 1;
         s->b_bidir_back_mv_table = s->b_bidir_back_mv_table_base + s->mb_stride + 1;

         s->b_direct_mv_table     = s->b_direct_mv_table_base + s->mb_stride + 1;
 
         /* Allocate MB type table */

         FF_ALLOCZ_OR_GOTO(s->avctx, s->mb_type, mb_array_size * sizeof(uint16_t), fail) // needed for encoding

         FF_ALLOCZ_OR_GOTO(s->avctx, s->lambda_table, mb_array_size * sizeof(int), fail)

 
         FF_ALLOC_OR_GOTO(s->avctx, s->cplx_tab,
                          mb_array_size * sizeof(float), fail);
         FF_ALLOC_OR_GOTO(s->avctx, s->bits_tab,
                          mb_array_size * sizeof(float), fail);
 
     }
 
     if (s->codec_id == AV_CODEC_ID_MPEG4 ||

         (s->avctx->flags & AV_CODEC_FLAG_INTERLACED_ME)) {

         /* interlaced direct mode decoding tables */
         for (i = 0; i < 2; i++) {
             int j, k;
             for (j = 0; j < 2; j++) {
                 for (k = 0; k < 2; k++) {
                     FF_ALLOCZ_OR_GOTO(s->avctx,
                                       s->b_field_mv_table_base[i][j][k],
                                       mv_table_size * 2 * sizeof(int16_t),
                                       fail);
                     s->b_field_mv_table[i][j][k] = s->b_field_mv_table_base[i][j][k] +
                                                    s->mb_stride + 1;
                 }

                 FF_ALLOCZ_OR_GOTO(s->avctx, s->b_field_select_table [i][j], mb_array_size * 2 * sizeof(uint8_t), fail)
                 FF_ALLOCZ_OR_GOTO(s->avctx, s->p_field_mv_table_base[i][j], mv_table_size * 2 * sizeof(int16_t), fail)
                 s->p_field_mv_table[i][j] = s->p_field_mv_table_base[i][j] + s->mb_stride + 1;

             }

             FF_ALLOCZ_OR_GOTO(s->avctx, s->p_field_select_table[i], mb_array_size * 2 * sizeof(uint8_t), fail)

         }
     }
     if (s->out_format == FMT_H263) {
         /* cbp values */

         FF_ALLOCZ_OR_GOTO(s->avctx, s->coded_block_base, y_size + (s->mb_height&1)*2*s->b8_stride, fail);

         s->coded_block = s->coded_block_base + s->b8_stride + 1;
 
         /* cbp, ac_pred, pred_dir */

         FF_ALLOCZ_OR_GOTO(s->avctx, s->cbp_table     , mb_array_size * sizeof(uint8_t), fail);
         FF_ALLOCZ_OR_GOTO(s->avctx, s->pred_dir_table, mb_array_size * sizeof(uint8_t), fail);

     }
 
     if (s->h263_pred || s->h263_plus || !s->encoding) {
         /* dc values */

         // MN: we need these for error resilience of intra-frames

         FF_ALLOCZ_OR_GOTO(s->avctx, s->dc_val_base, yc_size * sizeof(int16_t), fail);

         s->dc_val[0] = s->dc_val_base + s->b8_stride + 1;
         s->dc_val[1] = s->dc_val_base + y_size + s->mb_stride + 1;
         s->dc_val[2] = s->dc_val[1] + c_size;
         for (i = 0; i < yc_size; i++)
             s->dc_val_base[i] = 1024;
     }
 

     /* which mb is an intra block */

     FF_ALLOCZ_OR_GOTO(s->avctx, s->mbintra_table, mb_array_size, fail);
     memset(s->mbintra_table, 1, mb_array_size);
 
     /* init macroblock skip table */
     FF_ALLOCZ_OR_GOTO(s->avctx, s->mbskip_table, mb_array_size + 2, fail);

     // Note the + 1 is for a quicker MPEG-4 slice_end detection

     return ff_mpeg_er_init(s);

 fail:
     return AVERROR(ENOMEM);
 }
 

 static void clear_context(MpegEncContext *s)
 {
     int i, j, k;
 
     memset(&s->next_picture, 0, sizeof(s->next_picture));
     memset(&s->last_picture, 0, sizeof(s->last_picture));
     memset(&s->current_picture, 0, sizeof(s->current_picture));
     memset(&s->new_picture, 0, sizeof(s->new_picture));
 
     memset(s->thread_context, 0, sizeof(s->thread_context));
 
     s->me.map = NULL;
     s->me.score_map = NULL;
     s->dct_error_sum = NULL;
     s->block = NULL;
     s->blocks = NULL;

     s->block32 = NULL;

     memset(s->pblocks, 0, sizeof(s->pblocks));
     s->ac_val_base = NULL;
     s->ac_val[0] =
     s->ac_val[1] =
     s->ac_val[2] =NULL;
     s->sc.edge_emu_buffer = NULL;
     s->me.scratchpad = NULL;
     s->me.temp =
     s->sc.rd_scratchpad =
     s->sc.b_scratchpad =
     s->sc.obmc_scratchpad = NULL;
 

     s->bitstream_buffer = NULL;
     s->allocated_bitstream_buffer_size = 0;
     s->picture          = NULL;
     s->mb_type          = NULL;
     s->p_mv_table_base  = NULL;
     s->b_forw_mv_table_base = NULL;
     s->b_back_mv_table_base = NULL;
     s->b_bidir_forw_mv_table_base = NULL;
     s->b_bidir_back_mv_table_base = NULL;
     s->b_direct_mv_table_base = NULL;
     s->p_mv_table            = NULL;
     s->b_forw_mv_table       = NULL;
     s->b_back_mv_table       = NULL;
     s->b_bidir_forw_mv_table = NULL;
     s->b_bidir_back_mv_table = NULL;
     s->b_direct_mv_table     = NULL;
     for (i = 0; i < 2; i++) {
         for (j = 0; j < 2; j++) {
             for (k = 0; k < 2; k++) {
                 s->b_field_mv_table_base[i][j][k] = NULL;
                 s->b_field_mv_table[i][j][k] = NULL;
             }
             s->b_field_select_table[i][j] = NULL;
             s->p_field_mv_table_base[i][j] = NULL;
             s->p_field_mv_table[i][j] = NULL;
         }
         s->p_field_select_table[i] = NULL;
     }
 
     s->dc_val_base = NULL;
     s->coded_block_base = NULL;
     s->mbintra_table = NULL;
     s->cbp_table = NULL;
     s->pred_dir_table = NULL;
 
     s->mbskip_table = NULL;
 
     s->er.error_status_table = NULL;
     s->er.er_temp_buffer = NULL;
     s->mb_index2xy = NULL;
     s->lambda_table = NULL;
 
     s->cplx_tab = NULL;
     s->bits_tab = NULL;
 }
 

 /**

  * init common structure for both encoder and decoder.
  * this assumes that some variables like width/height are already set
  */

 av_cold int ff_mpv_common_init(MpegEncContext *s)

 {

     int i, ret;

     int nb_slices = (HAVE_THREADS &&
                      s->avctx->active_thread_type & FF_THREAD_SLICE) ?
                     s->avctx->thread_count : 1;
 

     clear_context(s);
 

     if (s->encoding && s->avctx->slices)
         nb_slices = s->avctx->slices;

     if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO && !s->progressive_sequence)

         s->mb_height = (s->height + 31) / 32 * 2;

     else

         s->mb_height = (s->height + 15) / 16;

     if (s->avctx->pix_fmt == AV_PIX_FMT_NONE) {

         av_log(s->avctx, AV_LOG_ERROR,

                "decoding to AV_PIX_FMT_NONE is not supported.\n");

         return -1;
     }
 

     if (nb_slices > MAX_THREADS || (nb_slices > s->mb_height && s->mb_height)) {
         int max_slices;
         if (s->mb_height)
             max_slices = FFMIN(MAX_THREADS, s->mb_height);
         else
             max_slices = MAX_THREADS;
         av_log(s->avctx, AV_LOG_WARNING, "too many threads/slices (%d),"
                " reducing to %d\n", nb_slices, max_slices);
         nb_slices = max_slices;

     }
 

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

         return -1;
 

     dct_init(s);

     /* set chroma shifts */

     ret = av_pix_fmt_get_chroma_sub_sample(s->avctx->pix_fmt,
                                            &s->chroma_x_shift,
                                            &s->chroma_y_shift);
     if (ret)
         return ret;

     FF_ALLOCZ_OR_GOTO(s->avctx, s->picture,

                       MAX_PICTURE_COUNT * sizeof(Picture), fail);
     for (i = 0; i < MAX_PICTURE_COUNT; i++) {

         s->picture[i].f = av_frame_alloc();
         if (!s->picture[i].f)
             goto fail;

     }

     s->next_picture.f = av_frame_alloc();
     if (!s->next_picture.f)
         goto fail;
     s->last_picture.f = av_frame_alloc();
     if (!s->last_picture.f)
         goto fail;
     s->current_picture.f = av_frame_alloc();
     if (!s->current_picture.f)
         goto fail;
     s->new_picture.f = av_frame_alloc();
     if (!s->new_picture.f)
         goto fail;

     if (init_context_frame(s))
         goto fail;

     s->parse_context.state = -1;

     s->context_initialized = 1;
     memset(s->thread_context, 0, sizeof(s->thread_context));
     s->thread_context[0]   = s;

 //     if (s->width && s->height) {

     if (nb_slices > 1) {
         for (i = 0; i < nb_slices; i++) {
             if (i) {
                 s->thread_context[i] = av_memdup(s, sizeof(MpegEncContext));
                 if (!s->thread_context[i])

                     goto fail;
             }

             if (init_duplicate_context(s->thread_context[i]) < 0)

                 goto fail;

             s->thread_context[i]->start_mb_y =
                 (s->mb_height * (i) + nb_slices / 2) / nb_slices;
             s->thread_context[i]->end_mb_y   =
                 (s->mb_height * (i + 1) + nb_slices / 2) / nb_slices;

         }

     } else {
         if (init_duplicate_context(s) < 0)
             goto fail;
         s->start_mb_y = 0;
         s->end_mb_y   = s->mb_height;
     }
     s->slice_context_count = nb_slices;

 //     }

     return 0;
  fail:

     ff_mpv_common_end(s);

     return -1;
 }
 

 /**
  * Frees and resets MpegEncContext fields depending on the resolution.
  * Is used during resolution changes to avoid a full reinitialization of the
  * codec.
  */

 static void free_context_frame(MpegEncContext *s)

 {

     int i, j, k;

     av_freep(&s->mb_type);

     av_freep(&s->p_mv_table_base);
     av_freep(&s->b_forw_mv_table_base);
     av_freep(&s->b_back_mv_table_base);
     av_freep(&s->b_bidir_forw_mv_table_base);
     av_freep(&s->b_bidir_back_mv_table_base);
     av_freep(&s->b_direct_mv_table_base);

     s->p_mv_table            = NULL;
     s->b_forw_mv_table       = NULL;
     s->b_back_mv_table       = NULL;
     s->b_bidir_forw_mv_table = NULL;
     s->b_bidir_back_mv_table = NULL;
     s->b_direct_mv_table     = NULL;
     for (i = 0; i < 2; i++) {
         for (j = 0; j < 2; j++) {
             for (k = 0; k < 2; k++) {

                 av_freep(&s->b_field_mv_table_base[i][j][k]);

                 s->b_field_mv_table[i][j][k] = NULL;

             }
             av_freep(&s->b_field_select_table[i][j]);
             av_freep(&s->p_field_mv_table_base[i][j]);

             s->p_field_mv_table[i][j] = NULL;

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

     av_freep(&s->dc_val_base);
     av_freep(&s->coded_block_base);

     av_freep(&s->mbintra_table);

     av_freep(&s->cbp_table);
     av_freep(&s->pred_dir_table);

     av_freep(&s->mbskip_table);

     av_freep(&s->er.error_status_table);
     av_freep(&s->er.er_temp_buffer);

     av_freep(&s->mb_index2xy);

     av_freep(&s->lambda_table);

     av_freep(&s->cplx_tab);
     av_freep(&s->bits_tab);
 
     s->linesize = s->uvlinesize = 0;
 }
 

 int ff_mpv_common_frame_size_change(MpegEncContext *s)

 {
     int i, err = 0;
 

     if (!s->context_initialized)
         return AVERROR(EINVAL);
 

     if (s->slice_context_count > 1) {
         for (i = 0; i < s->slice_context_count; i++) {
             free_duplicate_context(s->thread_context[i]);
         }
         for (i = 1; i < s->slice_context_count; i++) {
             av_freep(&s->thread_context[i]);
         }
     } else
         free_duplicate_context(s);
 

     free_context_frame(s);

 
     if (s->picture)

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

                 s->picture[i].needs_realloc = 1;
         }
 
     s->last_picture_ptr         =
     s->next_picture_ptr         =
     s->current_picture_ptr      = NULL;
 
     // init
     if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO && !s->progressive_sequence)
         s->mb_height = (s->height + 31) / 32 * 2;

     else

         s->mb_height = (s->height + 15) / 16;
 
     if ((s->width || s->height) &&

         (err = av_image_check_size(s->width, s->height, 0, s->avctx)) < 0)

         goto fail;

 
     if ((err = init_context_frame(s)))
         goto fail;
 

     memset(s->thread_context, 0, sizeof(s->thread_context));

     s->thread_context[0]   = s;
 
     if (s->width && s->height) {
         int nb_slices = s->slice_context_count;
         if (nb_slices > 1) {
             for (i = 0; i < nb_slices; i++) {

                 if (i) {

                     s->thread_context[i] = av_memdup(s, sizeof(MpegEncContext));
                     if (!s->thread_context[i]) {
                         err = AVERROR(ENOMEM);
                         goto fail;
                     }

                 }

                 if ((err = init_duplicate_context(s->thread_context[i])) < 0)

                     goto fail;

                 s->thread_context[i]->start_mb_y =
                     (s->mb_height * (i) + nb_slices / 2) / nb_slices;
                 s->thread_context[i]->end_mb_y   =
                     (s->mb_height * (i + 1) + nb_slices / 2) / nb_slices;

             }
         } else {

             err = init_duplicate_context(s);
             if (err < 0)

                 goto fail;
             s->start_mb_y = 0;
             s->end_mb_y   = s->mb_height;
         }
         s->slice_context_count = nb_slices;
     }
 
     return 0;
  fail:

     ff_mpv_common_end(s);

     return err;
 }
 

 /* init common structure for both encoder and decoder */

 void ff_mpv_common_end(MpegEncContext *s)

 {
     int i;
 

     if (!s)
         return ;
 

     if (s->slice_context_count > 1) {
         for (i = 0; i < s->slice_context_count; i++) {
             free_duplicate_context(s->thread_context[i]);
         }
         for (i = 1; i < s->slice_context_count; i++) {
             av_freep(&s->thread_context[i]);
         }
         s->slice_context_count = 1;
     } else free_duplicate_context(s);
 
     av_freep(&s->parse_context.buffer);
     s->parse_context.buffer_size = 0;
 
     av_freep(&s->bitstream_buffer);
     s->allocated_bitstream_buffer_size = 0;
 

     if (s->picture) {
         for (i = 0; i < MAX_PICTURE_COUNT; i++) {

             ff_free_picture_tables(&s->picture[i]);

             ff_mpeg_unref_picture(s->avctx, &s->picture[i]);

             av_frame_free(&s->picture[i].f);

         }

     }

     av_freep(&s->picture);

     ff_free_picture_tables(&s->last_picture);

     ff_mpeg_unref_picture(s->avctx, &s->last_picture);

     av_frame_free(&s->last_picture.f);

     ff_free_picture_tables(&s->current_picture);

     ff_mpeg_unref_picture(s->avctx, &s->current_picture);

     av_frame_free(&s->current_picture.f);

     ff_free_picture_tables(&s->next_picture);

     ff_mpeg_unref_picture(s->avctx, &s->next_picture);

     av_frame_free(&s->next_picture.f);
     ff_free_picture_tables(&s->new_picture);

     ff_mpeg_unref_picture(s->avctx, &s->new_picture);

     av_frame_free(&s->new_picture.f);

 
     free_context_frame(s);
 

     s->context_initialized      = 0;
     s->last_picture_ptr         =
     s->next_picture_ptr         =
     s->current_picture_ptr      = NULL;
     s->linesize = s->uvlinesize = 0;

 }
 

 static void gray_frame(AVFrame *frame)
 {
     int i, h_chroma_shift, v_chroma_shift;
 
     av_pix_fmt_get_chroma_sub_sample(frame->format, &h_chroma_shift, &v_chroma_shift);
 
     for(i=0; i<frame->height; i++)
         memset(frame->data[0] + frame->linesize[0]*i, 0x80, frame->width);

     for(i=0; i<AV_CEIL_RSHIFT(frame->height, v_chroma_shift); i++) {

         memset(frame->data[1] + frame->linesize[1]*i,

                0x80, AV_CEIL_RSHIFT(frame->width, h_chroma_shift));

         memset(frame->data[2] + frame->linesize[2]*i,

                0x80, AV_CEIL_RSHIFT(frame->width, h_chroma_shift));

     }
 }
 

 /**

  * generic function called after decoding
  * the header and before a frame is decoded.

  */

 int ff_mpv_frame_start(MpegEncContext *s, AVCodecContext *avctx)

 {

     int i, ret;

     Picture *pic;

     s->mb_skipped = 0;

     if (!ff_thread_can_start_frame(avctx)) {
         av_log(avctx, AV_LOG_ERROR, "Attempt to start a frame outside SETUP state\n");
         return -1;
     }
 

     /* mark & release old frames */

     if (s->pict_type != AV_PICTURE_TYPE_B && s->last_picture_ptr &&
         s->last_picture_ptr != s->next_picture_ptr &&

         s->last_picture_ptr->f->buf[0]) {

         ff_mpeg_unref_picture(s->avctx, s->last_picture_ptr);

     }

     /* release forgotten pictures */

     /* if (MPEG-124 / H.263) */

     for (i = 0; i < MAX_PICTURE_COUNT; i++) {
         if (&s->picture[i] != s->last_picture_ptr &&
             &s->picture[i] != s->next_picture_ptr &&
             s->picture[i].reference && !s->picture[i].needs_realloc) {

             ff_mpeg_unref_picture(s->avctx, &s->picture[i]);

         }

     }

     ff_mpeg_unref_picture(s->avctx, &s->current_picture);

     ff_mpeg_unref_picture(s->avctx, &s->last_picture);
     ff_mpeg_unref_picture(s->avctx, &s->next_picture);

     /* release non reference frames */
     for (i = 0; i < MAX_PICTURE_COUNT; i++) {
         if (!s->picture[i].reference)
             ff_mpeg_unref_picture(s->avctx, &s->picture[i]);
     }

     if (s->current_picture_ptr && !s->current_picture_ptr->f->buf[0]) {

         // we already have an unused image

         // (maybe it was set before reading the header)
         pic = s->current_picture_ptr;
     } else {

         i   = ff_find_unused_picture(s->avctx, s->picture, 0);

         if (i < 0) {
             av_log(s->avctx, AV_LOG_ERROR, "no frame buffer available\n");
             return i;

         }

         pic = &s->picture[i];
     }

     pic->reference = 0;
     if (!s->droppable) {
         if (s->pict_type != AV_PICTURE_TYPE_B)
             pic->reference = 3;
     }

     pic->f->coded_picture_number = s->coded_picture_number++;

     if (alloc_picture(s, pic, 0) < 0)

         return -1;

     s->current_picture_ptr = pic;
     // FIXME use only the vars from current_pic

     s->current_picture_ptr->f->top_field_first = s->top_field_first;

     if (s->codec_id == AV_CODEC_ID_MPEG1VIDEO ||
         s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
         if (s->picture_structure != PICT_FRAME)

             s->current_picture_ptr->f->top_field_first =

                 (s->picture_structure == PICT_TOP_FIELD) == s->first_field;

     }

     s->current_picture_ptr->f->interlaced_frame = !s->progressive_frame &&

                                                  !s->progressive_sequence;
     s->current_picture_ptr->field_picture      =  s->picture_structure != PICT_FRAME;

     s->current_picture_ptr->f->pict_type = s->pict_type;

     // if (s->avctx->flags && AV_CODEC_FLAG_QSCALE)

     //     s->current_picture_ptr->quality = s->new_picture_ptr->quality;

     s->current_picture_ptr->f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;

     if ((ret = ff_mpeg_ref_picture(s->avctx, &s->current_picture,

                                    s->current_picture_ptr)) < 0)
         return ret;

     if (s->pict_type != AV_PICTURE_TYPE_B) {

         s->last_picture_ptr = s->next_picture_ptr;

         if (!s->droppable)

             s->next_picture_ptr = s->current_picture_ptr;

     }

     ff_dlog(s->avctx, "L%p N%p C%p L%p N%p C%p type:%d drop:%d\n",

             s->last_picture_ptr, s->next_picture_ptr,s->current_picture_ptr,

             s->last_picture_ptr    ? s->last_picture_ptr->f->data[0]    : NULL,
             s->next_picture_ptr    ? s->next_picture_ptr->f->data[0]    : NULL,
             s->current_picture_ptr ? s->current_picture_ptr->f->data[0] : NULL,

             s->pict_type, s->droppable);

     if ((!s->last_picture_ptr || !s->last_picture_ptr->f->buf[0]) &&

         (s->pict_type != AV_PICTURE_TYPE_I)) {

         int h_chroma_shift, v_chroma_shift;
         av_pix_fmt_get_chroma_sub_sample(s->avctx->pix_fmt,
                                          &h_chroma_shift, &v_chroma_shift);

         if (s->pict_type == AV_PICTURE_TYPE_B && s->next_picture_ptr && s->next_picture_ptr->f->buf[0])

             av_log(avctx, AV_LOG_DEBUG,

                    "allocating dummy last picture for B frame\n");
         else if (s->pict_type != AV_PICTURE_TYPE_I)

             av_log(avctx, AV_LOG_ERROR,
                    "warning: first frame is no keyframe\n");
 
         /* Allocate a dummy frame */

         i = ff_find_unused_picture(s->avctx, s->picture, 0);

         if (i < 0) {
             av_log(s->avctx, AV_LOG_ERROR, "no frame buffer available\n");
             return i;

         }

         s->last_picture_ptr = &s->picture[i];

 
         s->last_picture_ptr->reference   = 3;

         s->last_picture_ptr->f->key_frame = 0;
         s->last_picture_ptr->f->pict_type = AV_PICTURE_TYPE_P;

         if (alloc_picture(s, s->last_picture_ptr, 0) < 0) {

             s->last_picture_ptr = NULL;
             return -1;

         }

         if (!avctx->hwaccel) {

             for(i=0; i<avctx->height; i++)

                 memset(s->last_picture_ptr->f->data[0] + s->last_picture_ptr->f->linesize[0]*i,

                        0x80, avctx->width);

             if (s->last_picture_ptr->f->data[2]) {

                 for(i=0; i<AV_CEIL_RSHIFT(avctx->height, v_chroma_shift); i++) {

                     memset(s->last_picture_ptr->f->data[1] + s->last_picture_ptr->f->linesize[1]*i,

                         0x80, AV_CEIL_RSHIFT(avctx->width, h_chroma_shift));

                     memset(s->last_picture_ptr->f->data[2] + s->last_picture_ptr->f->linesize[2]*i,

                         0x80, AV_CEIL_RSHIFT(avctx->width, h_chroma_shift));

                 }

             }
 
             if(s->codec_id == AV_CODEC_ID_FLV1 || s->codec_id == AV_CODEC_ID_H263){
                 for(i=0; i<avctx->height; i++)

                 memset(s->last_picture_ptr->f->data[0] + s->last_picture_ptr->f->linesize[0]*i, 16, avctx->width);

             }

         }

         ff_thread_report_progress(&s->last_picture_ptr->tf, INT_MAX, 0);
         ff_thread_report_progress(&s->last_picture_ptr->tf, INT_MAX, 1);
     }

     if ((!s->next_picture_ptr || !s->next_picture_ptr->f->buf[0]) &&

         s->pict_type == AV_PICTURE_TYPE_B) {
         /* Allocate a dummy frame */

         i = ff_find_unused_picture(s->avctx, s->picture, 0);

         if (i < 0) {
             av_log(s->avctx, AV_LOG_ERROR, "no frame buffer available\n");
             return i;

         }

         s->next_picture_ptr = &s->picture[i];

 
         s->next_picture_ptr->reference   = 3;

         s->next_picture_ptr->f->key_frame = 0;
         s->next_picture_ptr->f->pict_type = AV_PICTURE_TYPE_P;

         if (alloc_picture(s, s->next_picture_ptr, 0) < 0) {

             s->next_picture_ptr = NULL;
             return -1;

         }

         ff_thread_report_progress(&s->next_picture_ptr->tf, INT_MAX, 0);
         ff_thread_report_progress(&s->next_picture_ptr->tf, INT_MAX, 1);
     }

 #if 0 // BUFREF-FIXME

     memset(s->last_picture.f->data, 0, sizeof(s->last_picture.f->data));
     memset(s->next_picture.f->data, 0, sizeof(s->next_picture.f->data));

 #endif

     if (s->last_picture_ptr) {

         if (s->last_picture_ptr->f->buf[0] &&

             (ret = ff_mpeg_ref_picture(s->avctx, &s->last_picture,

                                        s->last_picture_ptr)) < 0)
             return ret;
     }
     if (s->next_picture_ptr) {

         if (s->next_picture_ptr->f->buf[0] &&

             (ret = ff_mpeg_ref_picture(s->avctx, &s->next_picture,

                                        s->next_picture_ptr)) < 0)
             return ret;
     }

     av_assert0(s->pict_type == AV_PICTURE_TYPE_I || (s->last_picture_ptr &&

                                                  s->last_picture_ptr->f->buf[0]));

     if (s->picture_structure!= PICT_FRAME) {

         int i;

         for (i = 0; i < 4; i++) {
             if (s->picture_structure == PICT_BOTTOM_FIELD) {

                 s->current_picture.f->data[i] +=
                     s->current_picture.f->linesize[i];

             }

             s->current_picture.f->linesize[i] *= 2;
             s->last_picture.f->linesize[i]    *= 2;
             s->next_picture.f->linesize[i]    *= 2;

         }
     }

     /* set dequantizer, we can't do it during init as

      * it might change for MPEG-4 and we can't do it in the header
      * decode as init is not called for MPEG-4 there yet */

     if (s->mpeg_quant || s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {

         s->dct_unquantize_intra = s->dct_unquantize_mpeg2_intra;
         s->dct_unquantize_inter = s->dct_unquantize_mpeg2_inter;

     } else if (s->out_format == FMT_H263 || s->out_format == FMT_H261) {

         s->dct_unquantize_intra = s->dct_unquantize_h263_intra;
         s->dct_unquantize_inter = s->dct_unquantize_h263_inter;

     } else {

         s->dct_unquantize_intra = s->dct_unquantize_mpeg1_intra;
         s->dct_unquantize_inter = s->dct_unquantize_mpeg1_inter;
     }

     if (s->avctx->debug & FF_DEBUG_NOMC) {
         gray_frame(s->current_picture_ptr->f);
     }
 

     return 0;

 }

 /* called after a frame has been decoded. */

 void ff_mpv_frame_end(MpegEncContext *s)

 {

     emms_c();

     if (s->current_picture.reference)

         ff_thread_report_progress(&s->current_picture_ptr->tf, INT_MAX, 0);

 }
 

 void ff_print_debug_info(MpegEncContext *s, Picture *p, AVFrame *pict)

 {

     ff_print_debug_info2(s->avctx, pict, s->mbskip_table, p->mb_type,
                          p->qscale_table, p->motion_val, &s->low_delay,

                          s->mb_width, s->mb_height, s->mb_stride, s->quarter_sample);

 }
 

 int ff_mpv_export_qp_table(MpegEncContext *s, AVFrame *f, Picture *p, int qp_type)
 {
     AVBufferRef *ref = av_buffer_ref(p->qscale_table_buf);
     int offset = 2*s->mb_stride + 1;
     if(!ref)
         return AVERROR(ENOMEM);
     av_assert0(ref->size >= offset + s->mb_stride * ((f->height+15)/16));
     ref->size -= offset;
     ref->data += offset;
     return av_frame_set_qp_table(f, ref, s->mb_stride, qp_type);
 }
 

 static inline int hpel_motion_lowres(MpegEncContext *s,
                                      uint8_t *dest, uint8_t *src,
                                      int field_based, int field_select,
                                      int src_x, int src_y,

                                      int width, int height, ptrdiff_t stride,

                                      int h_edge_pos, int v_edge_pos,
                                      int w, int h, h264_chroma_mc_func *pix_op,
                                      int motion_x, int motion_y)
 {
     const int lowres   = s->avctx->lowres;

     const int op_index = FFMIN(lowres, 3);

     const int s_mask   = (2 << lowres) - 1;
     int emu = 0;
     int sx, sy;
 
     if (s->quarter_sample) {
         motion_x /= 2;
         motion_y /= 2;
     }
 
     sx = motion_x & s_mask;
     sy = motion_y & s_mask;
     src_x += motion_x >> lowres + 1;
     src_y += motion_y >> lowres + 1;
 
     src   += src_y * stride + src_x;
 
     if ((unsigned)src_x > FFMAX( h_edge_pos - (!!sx) - w,                 0) ||
         (unsigned)src_y > FFMAX((v_edge_pos >> field_based) - (!!sy) - h, 0)) {

         s->vdsp.emulated_edge_mc(s->sc.edge_emu_buffer, src,

                                  s->linesize, s->linesize,
                                  w + 1, (h + 1) << field_based,
                                  src_x, src_y   << field_based,
                                  h_edge_pos, v_edge_pos);

         src = s->sc.edge_emu_buffer;

         emu = 1;
     }
 
     sx = (sx << 2) >> lowres;
     sy = (sy << 2) >> lowres;
     if (field_select)
         src += s->linesize;
     pix_op[op_index](dest, src, stride, h, sx, sy);
     return emu;
 }
 
 /* apply one mpeg motion vector to the three components */
 static av_always_inline void mpeg_motion_lowres(MpegEncContext *s,
                                                 uint8_t *dest_y,
                                                 uint8_t *dest_cb,
                                                 uint8_t *dest_cr,
                                                 int field_based,
                                                 int bottom_field,
                                                 int field_select,
                                                 uint8_t **ref_picture,
                                                 h264_chroma_mc_func *pix_op,
                                                 int motion_x, int motion_y,
                                                 int h, int mb_y)
 {
     uint8_t *ptr_y, *ptr_cb, *ptr_cr;

     int mx, my, src_x, src_y, uvsrc_x, uvsrc_y, sx, sy, uvsx, uvsy;
     ptrdiff_t uvlinesize, linesize;

     const int lowres     = s->avctx->lowres;

     const int op_index   = FFMIN(lowres-1+s->chroma_x_shift, 3);

     const int block_s    = 8>>lowres;
     const int s_mask     = (2 << lowres) - 1;
     const int h_edge_pos = s->h_edge_pos >> lowres;
     const int v_edge_pos = s->v_edge_pos >> lowres;

     linesize   = s->current_picture.f->linesize[0] << field_based;
     uvlinesize = s->current_picture.f->linesize[1] << field_based;

 
     // FIXME obviously not perfect but qpel will not work in lowres anyway
     if (s->quarter_sample) {
         motion_x /= 2;
         motion_y /= 2;
     }
 
     if(field_based){
         motion_y += (bottom_field - field_select)*((1 << lowres)-1);
     }
 
     sx = motion_x & s_mask;
     sy = motion_y & s_mask;
     src_x = s->mb_x * 2 * block_s + (motion_x >> lowres + 1);
     src_y = (mb_y * 2 * block_s >> field_based) + (motion_y >> lowres + 1);
 
     if (s->out_format == FMT_H263) {
         uvsx    = ((motion_x >> 1) & s_mask) | (sx & 1);
         uvsy    = ((motion_y >> 1) & s_mask) | (sy & 1);
         uvsrc_x = src_x >> 1;
         uvsrc_y = src_y >> 1;
     } else if (s->out_format == FMT_H261) {
         // even chroma mv's are full pel in H261
         mx      = motion_x / 4;
         my      = motion_y / 4;
         uvsx    = (2 * mx) & s_mask;
         uvsy    = (2 * my) & s_mask;
         uvsrc_x = s->mb_x * block_s + (mx >> lowres);
         uvsrc_y =    mb_y * block_s + (my >> lowres);
     } else {
         if(s->chroma_y_shift){
             mx      = motion_x / 2;
             my      = motion_y / 2;
             uvsx    = mx & s_mask;
             uvsy    = my & s_mask;
             uvsrc_x = s->mb_x * block_s                 + (mx >> lowres + 1);
             uvsrc_y =   (mb_y * block_s >> field_based) + (my >> lowres + 1);
         } else {
             if(s->chroma_x_shift){
             //Chroma422
                 mx = motion_x / 2;
                 uvsx = mx & s_mask;
                 uvsy = motion_y & s_mask;
                 uvsrc_y = src_y;
                 uvsrc_x = s->mb_x*block_s               + (mx >> (lowres+1));
             } else {
             //Chroma444
                 uvsx = motion_x & s_mask;
                 uvsy = motion_y & s_mask;
                 uvsrc_x = src_x;
                 uvsrc_y = src_y;
             }
         }
     }
 
     ptr_y  = ref_picture[0] + src_y   * linesize   + src_x;
     ptr_cb = ref_picture[1] + uvsrc_y * uvlinesize + uvsrc_x;
     ptr_cr = ref_picture[2] + uvsrc_y * uvlinesize + uvsrc_x;
 

     if ((unsigned) src_x > FFMAX( h_edge_pos - (!!sx) - 2 * block_s,       0) || uvsrc_y<0 ||

         (unsigned) src_y > FFMAX((v_edge_pos >> field_based) - (!!sy) - h, 0)) {

         s->vdsp.emulated_edge_mc(s->sc.edge_emu_buffer, ptr_y,

                                  linesize >> field_based, linesize >> field_based,
                                  17, 17 + field_based,

                                 src_x, src_y << field_based, h_edge_pos,
                                 v_edge_pos);

         ptr_y = s->sc.edge_emu_buffer;

         if (!CONFIG_GRAY || !(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {

             uint8_t *ubuf = s->sc.edge_emu_buffer + 18 * s->linesize;

             uint8_t *vbuf =ubuf + 10 * s->uvlinesize;

             if (s->workaround_bugs & FF_BUG_IEDGE)
                 vbuf -= s->uvlinesize;

             s->vdsp.emulated_edge_mc(ubuf,  ptr_cb,

                                      uvlinesize >> field_based, uvlinesize >> field_based,
                                      9, 9 + field_based,

                                     uvsrc_x, uvsrc_y << field_based,
                                     h_edge_pos >> 1, v_edge_pos >> 1);

             s->vdsp.emulated_edge_mc(vbuf,  ptr_cr,

                                      uvlinesize >> field_based,uvlinesize >> field_based,
                                      9, 9 + field_based,

                                     uvsrc_x, uvsrc_y << field_based,
                                     h_edge_pos >> 1, v_edge_pos >> 1);

             ptr_cb = ubuf;
             ptr_cr = vbuf;

         }
     }
 

     // FIXME use this for field pix too instead of the obnoxious hack which changes picture.f->data

     if (bottom_field) {
         dest_y  += s->linesize;
         dest_cb += s->uvlinesize;
         dest_cr += s->uvlinesize;
     }
 
     if (field_select) {
         ptr_y   += s->linesize;
         ptr_cb  += s->uvlinesize;
         ptr_cr  += s->uvlinesize;
     }
 
     sx = (sx << 2) >> lowres;
     sy = (sy << 2) >> lowres;
     pix_op[lowres - 1](dest_y, ptr_y, linesize, h, sx, sy);
 

     if (!CONFIG_GRAY || !(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {

         int hc = s->chroma_y_shift ? (h+1-bottom_field)>>1 : h;

         uvsx = (uvsx << 2) >> lowres;
         uvsy = (uvsy << 2) >> lowres;

         if (hc) {
             pix_op[op_index](dest_cb, ptr_cb, uvlinesize, hc, uvsx, uvsy);
             pix_op[op_index](dest_cr, ptr_cr, uvlinesize, hc, uvsx, uvsy);

         }
     }
     // FIXME h261 lowres loop filter
 }
 
 static inline void chroma_4mv_motion_lowres(MpegEncContext *s,
                                             uint8_t *dest_cb, uint8_t *dest_cr,
                                             uint8_t **ref_picture,
                                             h264_chroma_mc_func * pix_op,
                                             int mx, int my)
 {
     const int lowres     = s->avctx->lowres;

     const int op_index   = FFMIN(lowres, 3);

     const int block_s    = 8 >> lowres;
     const int s_mask     = (2 << lowres) - 1;
     const int h_edge_pos = s->h_edge_pos >> lowres + 1;
     const int v_edge_pos = s->v_edge_pos >> lowres + 1;

     int emu = 0, src_x, src_y, sx, sy;
     ptrdiff_t offset;

     uint8_t *ptr;
 
     if (s->quarter_sample) {
         mx /= 2;
         my /= 2;
     }
 
     /* In case of 8X8, we construct a single chroma motion vector
        with a special rounding */
     mx = ff_h263_round_chroma(mx);
     my = ff_h263_round_chroma(my);
 
     sx = mx & s_mask;
     sy = my & s_mask;
     src_x = s->mb_x * block_s + (mx >> lowres + 1);
     src_y = s->mb_y * block_s + (my >> lowres + 1);
 
     offset = src_y * s->uvlinesize + src_x;
     ptr = ref_picture[1] + offset;

     if ((unsigned) src_x > FFMAX(h_edge_pos - (!!sx) - block_s, 0) ||
         (unsigned) src_y > FFMAX(v_edge_pos - (!!sy) - block_s, 0)) {

         s->vdsp.emulated_edge_mc(s->sc.edge_emu_buffer, ptr,

                                  s->uvlinesize, s->uvlinesize,
                                  9, 9,
                                  src_x, src_y, h_edge_pos, v_edge_pos);

         ptr = s->sc.edge_emu_buffer;

         emu = 1;

     }
     sx = (sx << 2) >> lowres;
     sy = (sy << 2) >> lowres;
     pix_op[op_index](dest_cb, ptr, s->uvlinesize, block_s, sx, sy);
 
     ptr = ref_picture[2] + offset;
     if (emu) {

         s->vdsp.emulated_edge_mc(s->sc.edge_emu_buffer, ptr,

                                  s->uvlinesize, s->uvlinesize,
                                  9, 9,
                                  src_x, src_y, h_edge_pos, v_edge_pos);

         ptr = s->sc.edge_emu_buffer;

     }
     pix_op[op_index](dest_cr, ptr, s->uvlinesize, block_s, sx, sy);
 }
 
 /**
  * motion compensation of a single macroblock
  * @param s context
  * @param dest_y luma destination pointer
  * @param dest_cb chroma cb/u destination pointer
  * @param dest_cr chroma cr/v destination pointer
  * @param dir direction (0->forward, 1->backward)
  * @param ref_picture array[3] of pointers to the 3 planes of the reference picture
  * @param pix_op halfpel motion compensation function (average or put normally)
  * the motion vectors are taken from s->mv and the MV type from s->mv_type
  */
 static inline void MPV_motion_lowres(MpegEncContext *s,
                                      uint8_t *dest_y, uint8_t *dest_cb,
                                      uint8_t *dest_cr,
                                      int dir, uint8_t **ref_picture,
                                      h264_chroma_mc_func *pix_op)
 {
     int mx, my;
     int mb_x, mb_y, i;
     const int lowres  = s->avctx->lowres;
     const int block_s = 8 >>lowres;
 
     mb_x = s->mb_x;
     mb_y = s->mb_y;
 
     switch (s->mv_type) {
     case MV_TYPE_16X16:
         mpeg_motion_lowres(s, dest_y, dest_cb, dest_cr,
                            0, 0, 0,
                            ref_picture, pix_op,
                            s->mv[dir][0][0], s->mv[dir][0][1],
                            2 * block_s, mb_y);
         break;
     case MV_TYPE_8X8:
         mx = 0;
         my = 0;
         for (i = 0; i < 4; i++) {
             hpel_motion_lowres(s, dest_y + ((i & 1) + (i >> 1) *
                                s->linesize) * block_s,
                                ref_picture[0], 0, 0,
                                (2 * mb_x + (i & 1)) * block_s,
                                (2 * mb_y + (i >> 1)) * block_s,
                                s->width, s->height, s->linesize,
                                s->h_edge_pos >> lowres, s->v_edge_pos >> lowres,
                                block_s, block_s, pix_op,
                                s->mv[dir][i][0], s->mv[dir][i][1]);
 
             mx += s->mv[dir][i][0];
             my += s->mv[dir][i][1];
         }
 

         if (!CONFIG_GRAY || !(s->avctx->flags & AV_CODEC_FLAG_GRAY))

             chroma_4mv_motion_lowres(s, dest_cb, dest_cr, ref_picture,
                                      pix_op, mx, my);
         break;
     case MV_TYPE_FIELD:
         if (s->picture_structure == PICT_FRAME) {
             /* top field */
             mpeg_motion_lowres(s, dest_y, dest_cb, dest_cr,
                                1, 0, s->field_select[dir][0],
                                ref_picture, pix_op,
                                s->mv[dir][0][0], s->mv[dir][0][1],
                                block_s, mb_y);
             /* bottom field */
             mpeg_motion_lowres(s, dest_y, dest_cb, dest_cr,
                                1, 1, s->field_select[dir][1],
                                ref_picture, pix_op,
                                s->mv[dir][1][0], s->mv[dir][1][1],
                                block_s, mb_y);
         } else {
             if (s->picture_structure != s->field_select[dir][0] + 1 &&
                 s->pict_type != AV_PICTURE_TYPE_B && !s->first_field) {

                 ref_picture = s->current_picture_ptr->f->data;

 
             }
             mpeg_motion_lowres(s, dest_y, dest_cb, dest_cr,
                                0, 0, s->field_select[dir][0],
                                ref_picture, pix_op,
                                s->mv[dir][0][0],
                                s->mv[dir][0][1], 2 * block_s, mb_y >> 1);
             }
         break;
     case MV_TYPE_16X8:
         for (i = 0; i < 2; i++) {
             uint8_t **ref2picture;
 
             if (s->picture_structure == s->field_select[dir][i] + 1 ||
                 s->pict_type == AV_PICTURE_TYPE_B || s->first_field) {
                 ref2picture = ref_picture;
             } else {

                 ref2picture = s->current_picture_ptr->f->data;

             }
 
             mpeg_motion_lowres(s, dest_y, dest_cb, dest_cr,
                                0, 0, s->field_select[dir][i],
                                ref2picture, pix_op,
                                s->mv[dir][i][0], s->mv[dir][i][1] +
                                2 * block_s * i, block_s, mb_y >> 1);
 
             dest_y  +=  2 * block_s *  s->linesize;
             dest_cb += (2 * block_s >> s->chroma_y_shift) * s->uvlinesize;
             dest_cr += (2 * block_s >> s->chroma_y_shift) * s->uvlinesize;
         }
         break;
     case MV_TYPE_DMV:
         if (s->picture_structure == PICT_FRAME) {
             for (i = 0; i < 2; i++) {
                 int j;
                 for (j = 0; j < 2; j++) {
                     mpeg_motion_lowres(s, dest_y, dest_cb, dest_cr,
                                        1, j, j ^ i,
                                        ref_picture, pix_op,
                                        s->mv[dir][2 * i + j][0],
                                        s->mv[dir][2 * i + j][1],
                                        block_s, mb_y);
                 }

                 pix_op = s->h264chroma.avg_h264_chroma_pixels_tab;

             }
         } else {
             for (i = 0; i < 2; i++) {
                 mpeg_motion_lowres(s, dest_y, dest_cb, dest_cr,
                                    0, 0, s->picture_structure != i + 1,
                                    ref_picture, pix_op,
                                    s->mv[dir][2 * i][0],s->mv[dir][2 * i][1],
                                    2 * block_s, mb_y >> 1);
 
                 // after put we make avg of the same block

                 pix_op = s->h264chroma.avg_h264_chroma_pixels_tab;

 
                 // opposite parity is always in the same
                 // frame if this is second field
                 if (!s->first_field) {

                     ref_picture = s->current_picture_ptr->f->data;

                 }
             }
         }
         break;
     default:

         av_assert2(0);

     }
 }
 

 /**
  * find the lowest MB row referenced in the MVs
  */

 static int lowest_referenced_row(MpegEncContext *s, int dir)

 {
     int my_max = INT_MIN, my_min = INT_MAX, qpel_shift = !s->quarter_sample;
     int my, off, i, mvs;
 

     if (s->picture_structure != PICT_FRAME || s->mcsel)
         goto unhandled;

 
     switch (s->mv_type) {
         case MV_TYPE_16X16:
             mvs = 1;
             break;
         case MV_TYPE_16X8:
             mvs = 2;
             break;
         case MV_TYPE_8X8:
             mvs = 4;
             break;
         default:
             goto unhandled;
     }
 
     for (i = 0; i < mvs; i++) {

         my = s->mv[dir][i][1];

         my_max = FFMAX(my_max, my);
         my_min = FFMIN(my_min, my);
     }
 

     off = ((FFMAX(-my_min, my_max)<<qpel_shift) + 63) >> 6;

     return av_clip(s->mb_y + off, 0, s->mb_height - 1);

 unhandled:
     return s->mb_height-1;
 }
 

 /* put block[] to dest[] */

 static inline void put_dct(MpegEncContext *s,

                            int16_t *block, int i, uint8_t *dest, int line_size, int qscale)

 {

     s->dct_unquantize_intra(s, block, i, qscale);

     s->idsp.idct_put(dest, line_size, block);

 }
 
 /* add block[] to dest[] */

 static inline void add_dct(MpegEncContext *s,

                            int16_t *block, int i, uint8_t *dest, int line_size)

 {

     if (s->block_last_index[i] >= 0) {

         s->idsp.idct_add(dest, line_size, block);

     }
 }

 static inline void add_dequant_dct(MpegEncContext *s,

                            int16_t *block, int i, uint8_t *dest, int line_size, int qscale)

 {

     if (s->block_last_index[i] >= 0) {

         s->dct_unquantize_inter(s, block, i, qscale);

         s->idsp.idct_add(dest, line_size, block);

     }
 }
 

 /**

  * Clean dc, ac, coded_block for the current non-intra MB.

  */
 void ff_clean_intra_table_entries(MpegEncContext *s)
 {

     int wrap = s->b8_stride;

     int xy = s->block_index[0];

 
     s->dc_val[0][xy           ] =
     s->dc_val[0][xy + 1       ] =

     s->dc_val[0][xy     + wrap] =
     s->dc_val[0][xy + 1 + wrap] = 1024;
     /* ac pred */

     memset(s->ac_val[0][xy       ], 0, 32 * sizeof(int16_t));
     memset(s->ac_val[0][xy + wrap], 0, 32 * sizeof(int16_t));

     if (s->msmpeg4_version>=3) {
         s->coded_block[xy           ] =
         s->coded_block[xy + 1       ] =
         s->coded_block[xy     + wrap] =
         s->coded_block[xy + 1 + wrap] = 0;
     }
     /* chroma */

     wrap = s->mb_stride;
     xy = s->mb_x + s->mb_y * wrap;

     s->dc_val[1][xy] =
     s->dc_val[2][xy] = 1024;
     /* ac pred */

     memset(s->ac_val[1][xy], 0, 16 * sizeof(int16_t));
     memset(s->ac_val[2][xy], 0, 16 * sizeof(int16_t));

     s->mbintra_table[xy]= 0;

 }
 

 /* generic function called after a macroblock has been parsed by the
    decoder or after it has been encoded by the encoder.
 
    Important variables used:
    s->mb_intra : true if intra macroblock
    s->mv_dir   : motion vector direction
    s->mv_type  : motion vector type
    s->mv       : motion vector
    s->interlaced_dct : true if interlaced dct used (mpeg2)
  */

 static av_always_inline

 void mpv_reconstruct_mb_internal(MpegEncContext *s, int16_t block[12][64],

                             int lowres_flag, int is_mpeg12)

 {

     const int mb_xy = s->mb_y * s->mb_stride + s->mb_x;

     if (CONFIG_XVMC &&
         s->avctx->hwaccel && s->avctx->hwaccel->decode_mb) {
         s->avctx->hwaccel->decode_mb(s);//xvmc uses pblocks

         return;
     }

     if(s->avctx->debug&FF_DEBUG_DCT_COEFF) {

        /* print DCT coefficients */

        int i,j;

        av_log(s->avctx, AV_LOG_DEBUG, "DCT coeffs of MB at %dx%d:\n", s->mb_x, s->mb_y);
        for(i=0; i<6; i++){
            for(j=0; j<64; j++){

                av_log(s->avctx, AV_LOG_DEBUG, "%5d",
                       block[i][s->idsp.idct_permutation[j]]);

            }
            av_log(s->avctx, AV_LOG_DEBUG, "\n");
        }

     }
 

     s->current_picture.qscale_table[mb_xy] = s->qscale;

     /* update DC predictors for P macroblocks */
     if (!s->mb_intra) {

         if (!is_mpeg12 && (s->h263_pred || s->h263_aic)) {

             if(s->mbintra_table[mb_xy])

                 ff_clean_intra_table_entries(s);

         } else {

             s->last_dc[0] =
             s->last_dc[1] =

             s->last_dc[2] = 128 << s->intra_dc_precision;
         }
     }

     else if (!is_mpeg12 && (s->h263_pred || s->h263_aic))

         s->mbintra_table[mb_xy]=1;

     if ((s->avctx->flags & AV_CODEC_FLAG_PSNR) || s->frame_skip_threshold || s->frame_skip_factor ||

         !(s->encoding && (s->intra_only || s->pict_type == AV_PICTURE_TYPE_B) &&
           s->avctx->mb_decision != FF_MB_DECISION_RD)) { // FIXME precalc

         uint8_t *dest_y, *dest_cb, *dest_cr;

         int dct_linesize, dct_offset;

         op_pixels_func (*op_pix)[4];
         qpel_mc_func (*op_qpix)[16];

         const int linesize   = s->current_picture.f->linesize[0]; //not s->linesize as this would be wrong for field pics
         const int uvlinesize = s->current_picture.f->linesize[1];

         const int readable= s->pict_type != AV_PICTURE_TYPE_B || s->encoding || s->avctx->draw_horiz_band || lowres_flag;
         const int block_size= lowres_flag ? 8>>s->avctx->lowres : 8;

         /* avoid copy if macroblock skipped in last frame too */
         /* skip only during decoding as we might trash the buffers during encoding a bit */
         if(!s->encoding){

             uint8_t *mbskip_ptr = &s->mbskip_table[mb_xy];

             if (s->mb_skipped) {
                 s->mb_skipped= 0;

                 av_assert2(s->pict_type!=AV_PICTURE_TYPE_I);

                 *mbskip_ptr = 1;

             } else if(!s->current_picture.reference) {

                 *mbskip_ptr = 1;

             } else{

                 *mbskip_ptr = 0; /* not skipped */
             }

         }

         dct_linesize = linesize << s->interlaced_dct;

         dct_offset   = s->interlaced_dct ? linesize : linesize * block_size;

         if(readable){
             dest_y=  s->dest[0];
             dest_cb= s->dest[1];
             dest_cr= s->dest[2];
         }else{

             dest_y = s->sc.b_scratchpad;
             dest_cb= s->sc.b_scratchpad+16*linesize;
             dest_cr= s->sc.b_scratchpad+32*linesize;

         }

         if (!s->mb_intra) {
             /* motion handling */

             /* decoding or more than one mb_type (MC was already done otherwise) */

             if(!s->encoding){

                 if(HAVE_THREADS && s->avctx->active_thread_type&FF_THREAD_FRAME) {

                     if (s->mv_dir & MV_DIR_FORWARD) {

                         ff_thread_await_progress(&s->last_picture_ptr->tf,

                                                  lowest_referenced_row(s, 0),

                                                  0);

                     }
                     if (s->mv_dir & MV_DIR_BACKWARD) {

                         ff_thread_await_progress(&s->next_picture_ptr->tf,

                                                  lowest_referenced_row(s, 1),

                                                  0);

                     }
                 }
 

                 if(lowres_flag){

                     h264_chroma_mc_func *op_pix = s->h264chroma.put_h264_chroma_pixels_tab;

 
                     if (s->mv_dir & MV_DIR_FORWARD) {

                         MPV_motion_lowres(s, dest_y, dest_cb, dest_cr, 0, s->last_picture.f->data, op_pix);

                         op_pix = s->h264chroma.avg_h264_chroma_pixels_tab;

                     }
                     if (s->mv_dir & MV_DIR_BACKWARD) {

                         MPV_motion_lowres(s, dest_y, dest_cb, dest_cr, 1, s->next_picture.f->data, op_pix);

                     }

                 }else{

                     op_qpix = s->me.qpel_put;

                     if ((!s->no_rounding) || s->pict_type==AV_PICTURE_TYPE_B){

                         op_pix = s->hdsp.put_pixels_tab;

                     }else{

                         op_pix = s->hdsp.put_no_rnd_pixels_tab;

                     }
                     if (s->mv_dir & MV_DIR_FORWARD) {

                         ff_mpv_motion(s, dest_y, dest_cb, dest_cr, 0, s->last_picture.f->data, op_pix, op_qpix);

                         op_pix = s->hdsp.avg_pixels_tab;

                         op_qpix= s->me.qpel_avg;
                     }
                     if (s->mv_dir & MV_DIR_BACKWARD) {

                         ff_mpv_motion(s, dest_y, dest_cb, dest_cr, 1, s->next_picture.f->data, op_pix, op_qpix);

                     }

                 }

             }
 

             /* skip dequant / idct if we are really late ;) */

             if(s->avctx->skip_idct){

                 if(  (s->avctx->skip_idct >= AVDISCARD_NONREF && s->pict_type == AV_PICTURE_TYPE_B)
                    ||(s->avctx->skip_idct >= AVDISCARD_NONKEY && s->pict_type != AV_PICTURE_TYPE_I)

                    || s->avctx->skip_idct >= AVDISCARD_ALL)
                     goto skip_idct;
             }

             /* add dct residue */

             if(s->encoding || !(   s->msmpeg4_version || s->codec_id==AV_CODEC_ID_MPEG1VIDEO || s->codec_id==AV_CODEC_ID_MPEG2VIDEO
                                 || (s->codec_id==AV_CODEC_ID_MPEG4 && !s->mpeg_quant))){

                 add_dequant_dct(s, block[0], 0, dest_y                          , dct_linesize, s->qscale);

                 add_dequant_dct(s, block[1], 1, dest_y              + block_size, dct_linesize, s->qscale);

                 add_dequant_dct(s, block[2], 2, dest_y + dct_offset             , dct_linesize, s->qscale);

                 add_dequant_dct(s, block[3], 3, dest_y + dct_offset + block_size, dct_linesize, s->qscale);

                 if (!CONFIG_GRAY || !(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {

                     if (s->chroma_y_shift){
                         add_dequant_dct(s, block[4], 4, dest_cb, uvlinesize, s->chroma_qscale);
                         add_dequant_dct(s, block[5], 5, dest_cr, uvlinesize, s->chroma_qscale);
                     }else{
                         dct_linesize >>= 1;
                         dct_offset >>=1;
                         add_dequant_dct(s, block[4], 4, dest_cb,              dct_linesize, s->chroma_qscale);
                         add_dequant_dct(s, block[5], 5, dest_cr,              dct_linesize, s->chroma_qscale);
                         add_dequant_dct(s, block[6], 6, dest_cb + dct_offset, dct_linesize, s->chroma_qscale);
                         add_dequant_dct(s, block[7], 7, dest_cr + dct_offset, dct_linesize, s->chroma_qscale);
                     }

                 }

             } else if(is_mpeg12 || (s->codec_id != AV_CODEC_ID_WMV2)){

                 add_dct(s, block[0], 0, dest_y                          , dct_linesize);

                 add_dct(s, block[1], 1, dest_y              + block_size, dct_linesize);

                 add_dct(s, block[2], 2, dest_y + dct_offset             , dct_linesize);

                 add_dct(s, block[3], 3, dest_y + dct_offset + block_size, dct_linesize);

                 if (!CONFIG_GRAY || !(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {

                     if(s->chroma_y_shift){//Chroma420
                         add_dct(s, block[4], 4, dest_cb, uvlinesize);
                         add_dct(s, block[5], 5, dest_cr, uvlinesize);
                     }else{
                         //chroma422
                         dct_linesize = uvlinesize << s->interlaced_dct;

                         dct_offset   = s->interlaced_dct ? uvlinesize : uvlinesize*block_size;

 
                         add_dct(s, block[4], 4, dest_cb, dct_linesize);
                         add_dct(s, block[5], 5, dest_cr, dct_linesize);
                         add_dct(s, block[6], 6, dest_cb+dct_offset, dct_linesize);
                         add_dct(s, block[7], 7, dest_cr+dct_offset, dct_linesize);
                         if(!s->chroma_x_shift){//Chroma444

                             add_dct(s, block[8], 8, dest_cb+block_size, dct_linesize);
                             add_dct(s, block[9], 9, dest_cr+block_size, dct_linesize);
                             add_dct(s, block[10], 10, dest_cb+block_size+dct_offset, dct_linesize);
                             add_dct(s, block[11], 11, dest_cr+block_size+dct_offset, dct_linesize);

                         }
                     }
                 }//fi gray
             }

             else if (CONFIG_WMV2_DECODER || CONFIG_WMV2_ENCODER) {

                 ff_wmv2_add_mb(s, block, dest_y, dest_cb, dest_cr);

             }

         } else {

             /* Only MPEG-4 Simple Studio Profile is supported in > 8-bit mode.
                TODO: Integrate 10-bit properly into mpegvideo.c so that ER works properly */
             if (s->avctx->bits_per_raw_sample > 8){
                 const int act_block_size = block_size * 2;
                 s->idsp.idct_put(dest_y,                           dct_linesize, (int16_t*)(*s->block32)[0]);
                 s->idsp.idct_put(dest_y              + act_block_size, dct_linesize, (int16_t*)(*s->block32)[1]);
                 s->idsp.idct_put(dest_y + dct_offset,              dct_linesize, (int16_t*)(*s->block32)[2]);
                 s->idsp.idct_put(dest_y + dct_offset + act_block_size, dct_linesize, (int16_t*)(*s->block32)[3]);
 
                 dct_linesize = uvlinesize << s->interlaced_dct;
                 dct_offset   = s->interlaced_dct ? uvlinesize : uvlinesize*block_size;
 
                 s->idsp.idct_put(dest_cb,              dct_linesize, (int16_t*)(*s->block32)[4]);
                 s->idsp.idct_put(dest_cr,              dct_linesize, (int16_t*)(*s->block32)[5]);
                 s->idsp.idct_put(dest_cb + dct_offset, dct_linesize, (int16_t*)(*s->block32)[6]);
                 s->idsp.idct_put(dest_cr + dct_offset, dct_linesize, (int16_t*)(*s->block32)[7]);
                 if(!s->chroma_x_shift){//Chroma444
                     s->idsp.idct_put(dest_cb + act_block_size,              dct_linesize, (int16_t*)(*s->block32)[8]);
                     s->idsp.idct_put(dest_cr + act_block_size,              dct_linesize, (int16_t*)(*s->block32)[9]);
                     s->idsp.idct_put(dest_cb + act_block_size + dct_offset, dct_linesize, (int16_t*)(*s->block32)[10]);
                     s->idsp.idct_put(dest_cr + act_block_size + dct_offset, dct_linesize, (int16_t*)(*s->block32)[11]);
                 }
             }

             /* dct only in intra block */

             else if(s->encoding || !(s->codec_id==AV_CODEC_ID_MPEG1VIDEO || s->codec_id==AV_CODEC_ID_MPEG2VIDEO)){

                 put_dct(s, block[0], 0, dest_y                          , dct_linesize, s->qscale);
                 put_dct(s, block[1], 1, dest_y              + block_size, dct_linesize, s->qscale);
                 put_dct(s, block[2], 2, dest_y + dct_offset             , dct_linesize, s->qscale);
                 put_dct(s, block[3], 3, dest_y + dct_offset + block_size, dct_linesize, s->qscale);

                 if (!CONFIG_GRAY || !(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {

                     if(s->chroma_y_shift){
                         put_dct(s, block[4], 4, dest_cb, uvlinesize, s->chroma_qscale);
                         put_dct(s, block[5], 5, dest_cr, uvlinesize, s->chroma_qscale);
                     }else{
                         dct_offset >>=1;
                         dct_linesize >>=1;
                         put_dct(s, block[4], 4, dest_cb,              dct_linesize, s->chroma_qscale);
                         put_dct(s, block[5], 5, dest_cr,              dct_linesize, s->chroma_qscale);
                         put_dct(s, block[6], 6, dest_cb + dct_offset, dct_linesize, s->chroma_qscale);
                         put_dct(s, block[7], 7, dest_cr + dct_offset, dct_linesize, s->chroma_qscale);
                     }

                 }
             }else{

                 s->idsp.idct_put(dest_y,                           dct_linesize, block[0]);
                 s->idsp.idct_put(dest_y              + block_size, dct_linesize, block[1]);
                 s->idsp.idct_put(dest_y + dct_offset,              dct_linesize, block[2]);
                 s->idsp.idct_put(dest_y + dct_offset + block_size, dct_linesize, block[3]);

                 if (!CONFIG_GRAY || !(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {

                     if(s->chroma_y_shift){

                         s->idsp.idct_put(dest_cb, uvlinesize, block[4]);
                         s->idsp.idct_put(dest_cr, uvlinesize, block[5]);

                     }else{
 
                         dct_linesize = uvlinesize << s->interlaced_dct;

                         dct_offset   = s->interlaced_dct ? uvlinesize : uvlinesize*block_size;

                         s->idsp.idct_put(dest_cb,              dct_linesize, block[4]);
                         s->idsp.idct_put(dest_cr,              dct_linesize, block[5]);
                         s->idsp.idct_put(dest_cb + dct_offset, dct_linesize, block[6]);
                         s->idsp.idct_put(dest_cr + dct_offset, dct_linesize, block[7]);

                         if(!s->chroma_x_shift){//Chroma444

                             s->idsp.idct_put(dest_cb + block_size,              dct_linesize, block[8]);
                             s->idsp.idct_put(dest_cr + block_size,              dct_linesize, block[9]);
                             s->idsp.idct_put(dest_cb + block_size + dct_offset, dct_linesize, block[10]);
                             s->idsp.idct_put(dest_cr + block_size + dct_offset, dct_linesize, block[11]);

                         }
                     }
                 }//gray

             }

         }

 skip_idct:

         if(!readable){

             s->hdsp.put_pixels_tab[0][0](s->dest[0], dest_y ,   linesize,16);

             if (!CONFIG_GRAY || !(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {

                 s->hdsp.put_pixels_tab[s->chroma_x_shift][0](s->dest[1], dest_cb, uvlinesize,16 >> s->chroma_y_shift);
                 s->hdsp.put_pixels_tab[s->chroma_x_shift][0](s->dest[2], dest_cr, uvlinesize,16 >> s->chroma_y_shift);

             }

         }

     }
 }
 

 void ff_mpv_reconstruct_mb(MpegEncContext *s, int16_t block[12][64])

 {

 #if !CONFIG_SMALL

     if(s->out_format == FMT_MPEG1) {

         if(s->avctx->lowres) mpv_reconstruct_mb_internal(s, block, 1, 1);
         else                 mpv_reconstruct_mb_internal(s, block, 0, 1);

     } else
 #endif

     if(s->avctx->lowres) mpv_reconstruct_mb_internal(s, block, 1, 0);
     else                  mpv_reconstruct_mb_internal(s, block, 0, 0);

 }
 

 void ff_mpeg_draw_horiz_band(MpegEncContext *s, int y, int h)
 {

     ff_draw_horiz_band(s->avctx, s->current_picture_ptr->f,
                        s->last_picture_ptr ? s->last_picture_ptr->f : NULL, y, h, s->picture_structure,

                        s->first_field, s->low_delay);

 }
 

 void ff_init_block_index(MpegEncContext *s){ //FIXME maybe rename

     const int linesize   = s->current_picture.f->linesize[0]; //not s->linesize as this would be wrong for field pics
     const int uvlinesize = s->current_picture.f->linesize[1];

     const int width_of_mb = (4 + (s->avctx->bits_per_raw_sample > 8)) - s->avctx->lowres;
     const int height_of_mb = 4 - s->avctx->lowres;

     s->block_index[0]= s->b8_stride*(s->mb_y*2    ) - 2 + s->mb_x*2;
     s->block_index[1]= s->b8_stride*(s->mb_y*2    ) - 1 + s->mb_x*2;
     s->block_index[2]= s->b8_stride*(s->mb_y*2 + 1) - 2 + s->mb_x*2;
     s->block_index[3]= s->b8_stride*(s->mb_y*2 + 1) - 1 + s->mb_x*2;
     s->block_index[4]= s->mb_stride*(s->mb_y + 1)                + s->b8_stride*s->mb_height*2 + s->mb_x - 1;
     s->block_index[5]= s->mb_stride*(s->mb_y + s->mb_height + 2) + s->b8_stride*s->mb_height*2 + s->mb_x - 1;

     //block_index is not used by mpeg2, so it is not affected by chroma_format
 

     s->dest[0] = s->current_picture.f->data[0] + (int)((s->mb_x - 1U) <<  width_of_mb);
     s->dest[1] = s->current_picture.f->data[1] + (int)((s->mb_x - 1U) << (width_of_mb - s->chroma_x_shift));
     s->dest[2] = s->current_picture.f->data[2] + (int)((s->mb_x - 1U) << (width_of_mb - s->chroma_x_shift));

     if(!(s->pict_type==AV_PICTURE_TYPE_B && s->avctx->draw_horiz_band && s->picture_structure==PICT_FRAME))

     {

         if(s->picture_structure==PICT_FRAME){

         s->dest[0] += s->mb_y *   linesize << height_of_mb;
         s->dest[1] += s->mb_y * uvlinesize << (height_of_mb - s->chroma_y_shift);
         s->dest[2] += s->mb_y * uvlinesize << (height_of_mb - s->chroma_y_shift);

         }else{

             s->dest[0] += (s->mb_y>>1) *   linesize << height_of_mb;
             s->dest[1] += (s->mb_y>>1) * uvlinesize << (height_of_mb - s->chroma_y_shift);
             s->dest[2] += (s->mb_y>>1) * uvlinesize << (height_of_mb - s->chroma_y_shift);

             av_assert1((s->mb_y&1) == (s->picture_structure == PICT_BOTTOM_FIELD));

         }

     }

 }
 

 void ff_mpeg_flush(AVCodecContext *avctx){
     int i;
     MpegEncContext *s = avctx->priv_data;

     if (!s || !s->picture)

         return;

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

         ff_mpeg_unref_picture(s->avctx, &s->picture[i]);

     s->current_picture_ptr = s->last_picture_ptr = s->next_picture_ptr = NULL;

     ff_mpeg_unref_picture(s->avctx, &s->current_picture);
     ff_mpeg_unref_picture(s->avctx, &s->last_picture);
     ff_mpeg_unref_picture(s->avctx, &s->next_picture);

     s->mb_x= s->mb_y= 0;

     s->closed_gop= 0;

     s->parse_context.state= -1;
     s->parse_context.frame_start_found= 0;
     s->parse_context.overread= 0;
     s->parse_context.overread_index= 0;
     s->parse_context.index= 0;
     s->parse_context.last_index= 0;

     s->bitstream_buffer_size=0;

     s->pp_time=0;

 }
 

 /**
  * set qscale and update qscale dependent variables.
  */
 void ff_set_qscale(MpegEncContext * s, int qscale)
 {
     if (qscale < 1)
         qscale = 1;
     else if (qscale > 31)
         qscale = 31;
 
     s->qscale = qscale;
     s->chroma_qscale= s->chroma_qscale_table[qscale];
 
     s->y_dc_scale= s->y_dc_scale_table[ qscale ];
     s->c_dc_scale= s->c_dc_scale_table[ s->chroma_qscale ];
 }

 void ff_mpv_report_decode_progress(MpegEncContext *s)

 {

     if (s->pict_type != AV_PICTURE_TYPE_B && !s->partitioned_frame && !s->er.error_occurred)

         ff_thread_report_progress(&s->current_picture_ptr->tf, s->mb_y, 0);

 }