/*

  * MPEG-4 encoder

  * Copyright (c) 2000,2001 Fabrice Bellard
  * Copyright (c) 2002-2010 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
  */
 

 #include "libavutil/attributes.h"

 #include "libavutil/log.h"
 #include "libavutil/opt.h"

 #include "mpegutils.h"

 #include "mpegvideo.h"
 #include "h263.h"
 #include "mpeg4video.h"
 

 /* The uni_DCtab_* tables below contain unified bits+length tables to encode DC

  * differences in MPEG-4. Unified in the sense that the specification specifies

  * this encoding in several steps. */
 static uint8_t  uni_DCtab_lum_len[512];
 static uint8_t  uni_DCtab_chrom_len[512];

 static uint16_t uni_DCtab_lum_bits[512];
 static uint16_t uni_DCtab_chrom_bits[512];
 

 /* Unified encoding tables for run length encoding of coefficients.
  * Unified in the sense that the specification specifies the encoding in several steps. */
 static uint32_t uni_mpeg4_intra_rl_bits[64 * 64 * 2 * 2];
 static uint8_t  uni_mpeg4_intra_rl_len[64 * 64 * 2 * 2];
 static uint32_t uni_mpeg4_inter_rl_bits[64 * 64 * 2 * 2];
 static uint8_t  uni_mpeg4_inter_rl_len[64 * 64 * 2 * 2];

 //#define UNI_MPEG4_ENC_INDEX(last, run, level) ((last) * 128 + (run) * 256 + (level))
 //#define UNI_MPEG4_ENC_INDEX(last, run, level) ((last) * 128 * 64 + (run) + (level) * 64)
 #define UNI_MPEG4_ENC_INDEX(last, run, level) ((last) * 128 * 64 + (run) * 128 + (level))

 /* MPEG-4

  * inter
  * max level: 24/6
  * max run: 53/63
  *
  * intra
  * max level: 53/16
  * max run: 29/41
  */

 
 /**

  * Return the number of bits that encoding the 8x8 block in block would need.

  * @param[in]  block_last_index last index in scantable order that refers to a non zero element in block.
  */

 static inline int get_block_rate(MpegEncContext *s, int16_t block[64],
                                  int block_last_index, uint8_t scantable[64])
 {
     int last = 0;

     int j;

     int rate = 0;
 
     for (j = 1; j <= block_last_index; j++) {
         const int index = scantable[j];
         int level = block[index];
         if (level) {
             level += 64;
             if ((level & (~127)) == 0) {
                 if (j < block_last_index)
                     rate += s->intra_ac_vlc_length[UNI_AC_ENC_INDEX(j - last - 1, level)];
                 else
                     rate += s->intra_ac_vlc_last_length[UNI_AC_ENC_INDEX(j - last - 1, level)];
             } else

                 rate += s->ac_esc_length;
 

             last = j;

         }
     }
 
     return rate;
 }
 
 /**

  * Restore the ac coefficients in block that have been changed by decide_ac_pred().

  * This function also restores s->block_last_index.
  * @param[in,out] block MB coefficients, these will be restored
  * @param[in] dir ac prediction direction for each 8x8 block
  * @param[out] st scantable for each 8x8 block

  * @param[in] zigzag_last_index index referring to the last non zero coefficient in zigzag order

  */

 static inline void restore_ac_coeffs(MpegEncContext *s, int16_t block[6][64],
                                      const int dir[6], uint8_t *st[6],
                                      const int zigzag_last_index[6])

 {
     int i, n;

     memcpy(s->block_last_index, zigzag_last_index, sizeof(int) * 6);

     for (n = 0; n < 6; n++) {

         int16_t *ac_val = s->ac_val[0][0] + s->block_index[n] * 16;
 

         st[n] = s->intra_scantable.permutated;
         if (dir[n]) {

             /* top prediction */

             for (i = 1; i < 8; i++)

                 block[n][s->idsp.idct_permutation[i]] = ac_val[i + 8];

         } else {

             /* left prediction */

             for (i = 1; i < 8; i++)

                 block[n][s->idsp.idct_permutation[i << 3]] = ac_val[i];

         }
     }
 }
 
 /**

  * Return the optimal value (0 or 1) for the ac_pred element for the given MB in MPEG-4.

  * This function will also update s->block_last_index and s->ac_val.
  * @param[in,out] block MB coefficients, these will be updated if 1 is returned
  * @param[in] dir ac prediction direction for each 8x8 block
  * @param[out] st scantable for each 8x8 block

  * @param[out] zigzag_last_index index referring to the last non zero coefficient in zigzag order

  */

 static inline int decide_ac_pred(MpegEncContext *s, int16_t block[6][64],
                                  const int dir[6], uint8_t *st[6],
                                  int zigzag_last_index[6])

 {

     int score = 0;

     int i, n;

     int8_t *const qscale_table = s->current_picture.qscale_table;

     memcpy(zigzag_last_index, s->block_last_index, sizeof(int) * 6);

     for (n = 0; n < 6; n++) {

         int16_t *ac_val, *ac_val1;
 

         score -= get_block_rate(s, block[n], s->block_last_index[n],
                                 s->intra_scantable.permutated);

         ac_val  = s->ac_val[0][0] + s->block_index[n] * 16;
         ac_val1 = ac_val;
         if (dir[n]) {
             const int xy = s->mb_x + s->mb_y * s->mb_stride - s->mb_stride;

             /* top prediction */

             ac_val -= s->block_wrap[n] * 16;
             if (s->mb_y == 0 || s->qscale == qscale_table[xy] || n == 2 || n == 3) {

                 /* same qscale */

                 for (i = 1; i < 8; i++) {

                     const int level = block[n][s->idsp.idct_permutation[i]];
                     block[n][s->idsp.idct_permutation[i]] = level - ac_val[i + 8];
                     ac_val1[i]     = block[n][s->idsp.idct_permutation[i << 3]];

                     ac_val1[i + 8] = level;

                 }

             } else {

                 /* different qscale, we must rescale */

                 for (i = 1; i < 8; i++) {

                     const int level = block[n][s->idsp.idct_permutation[i]];
                     block[n][s->idsp.idct_permutation[i]] = level - ROUNDED_DIV(ac_val[i + 8] * qscale_table[xy], s->qscale);
                     ac_val1[i]     = block[n][s->idsp.idct_permutation[i << 3]];

                     ac_val1[i + 8] = level;

                 }
             }

             st[n] = s->intra_h_scantable.permutated;
         } else {
             const int xy = s->mb_x - 1 + s->mb_y * s->mb_stride;

             /* left prediction */

             ac_val -= 16;
             if (s->mb_x == 0 || s->qscale == qscale_table[xy] || n == 1 || n == 3) {

                 /* same qscale */

                 for (i = 1; i < 8; i++) {

                     const int level = block[n][s->idsp.idct_permutation[i << 3]];
                     block[n][s->idsp.idct_permutation[i << 3]] = level - ac_val[i];

                     ac_val1[i]     = level;

                     ac_val1[i + 8] = block[n][s->idsp.idct_permutation[i]];

                 }

             } else {

                 /* different qscale, we must rescale */

                 for (i = 1; i < 8; i++) {

                     const int level = block[n][s->idsp.idct_permutation[i << 3]];
                     block[n][s->idsp.idct_permutation[i << 3]] = level - ROUNDED_DIV(ac_val[i] * qscale_table[xy], s->qscale);

                     ac_val1[i]     = level;

                     ac_val1[i + 8] = block[n][s->idsp.idct_permutation[i]];

                 }
             }

             st[n] = s->intra_v_scantable.permutated;

         }
 

         for (i = 63; i > 0; i--)  // FIXME optimize
             if (block[n][st[n][i]])
                 break;
         s->block_last_index[n] = i;

 
         score += get_block_rate(s, block[n], s->block_last_index[n], st[n]);
     }
 

     if (score < 0) {

         return 1;

     } else {

         restore_ac_coeffs(s, block, dir, st, zigzag_last_index);
         return 0;
     }
 }
 
 /**

  * modify mb_type & qscale so that encoding is actually possible in MPEG-4

  */

 void ff_clean_mpeg4_qscales(MpegEncContext *s)
 {

     int i;

     int8_t *const qscale_table = s->current_picture.qscale_table;

 
     ff_clean_h263_qscales(s);
 

     if (s->pict_type == AV_PICTURE_TYPE_B) {
         int odd = 0;
         /* ok, come on, this isn't funny anymore, there's more code for

          * handling this MPEG-4 mess than for the actual adaptive quantization */

         for (i = 0; i < s->mb_num; i++) {
             int mb_xy = s->mb_index2xy[i];
             odd += qscale_table[mb_xy] & 1;

         }
 

         if (2 * odd > s->mb_num)
             odd = 1;
         else
             odd = 0;

         for (i = 0; i < s->mb_num; i++) {
             int mb_xy = s->mb_index2xy[i];
             if ((qscale_table[mb_xy] & 1) != odd)

                 qscale_table[mb_xy]++;

             if (qscale_table[mb_xy] > 31)
                 qscale_table[mb_xy] = 31;

         }
 

         for (i = 1; i < s->mb_num; i++) {
             int mb_xy = s->mb_index2xy[i];
             if (qscale_table[mb_xy] != qscale_table[s->mb_index2xy[i - 1]] &&
                 (s->mb_type[mb_xy] & CANDIDATE_MB_TYPE_DIRECT)) {
                 s->mb_type[mb_xy] |= CANDIDATE_MB_TYPE_BIDIR;

             }
         }
     }
 }
 
 /**

  * Encode the dc value.

  * @param n block index (0-3 are luma, 4-5 are chroma)
  */

 static inline void mpeg4_encode_dc(PutBitContext *s, int level, int n)

 {

     /* DC will overflow if level is outside the [-255,255] range. */

     level += 256;

     if (n < 4) {
         /* luminance */
         put_bits(s, uni_DCtab_lum_len[level], uni_DCtab_lum_bits[level]);
     } else {
         /* chrominance */
         put_bits(s, uni_DCtab_chrom_len[level], uni_DCtab_chrom_bits[level]);
     }
 }
 

 static inline int mpeg4_get_dc_length(int level, int n)
 {
     if (n < 4)

         return uni_DCtab_lum_len[level + 256];

     else

         return uni_DCtab_chrom_len[level + 256];
 }
 
 /**

  * Encode an 8x8 block.

  * @param n block index (0-3 are luma, 4-5 are chroma)
  */

 static inline void mpeg4_encode_block(MpegEncContext *s,
                                       int16_t *block, int n, int intra_dc,
                                       uint8_t *scan_table, PutBitContext *dc_pb,
                                       PutBitContext *ac_pb)

 {
     int i, last_non_zero;
     uint32_t *bits_tab;
     uint8_t *len_tab;
     const int last_index = s->block_last_index[n];
 

     if (s->mb_intra) {  // Note gcc (3.2.1 at least) will optimize this away

         /* MPEG-4 based DC predictor */

         mpeg4_encode_dc(dc_pb, intra_dc, n);

         if (last_index < 1)
             return;

         i = 1;

         bits_tab = uni_mpeg4_intra_rl_bits;
         len_tab  = uni_mpeg4_intra_rl_len;

     } else {

         if (last_index < 0)
             return;

         i = 0;

         bits_tab = uni_mpeg4_inter_rl_bits;
         len_tab  = uni_mpeg4_inter_rl_len;

     }
 
     /* AC coefs */
     last_non_zero = i - 1;
     for (; i < last_index; i++) {

         int level = block[scan_table[i]];

         if (level) {
             int run = i - last_non_zero - 1;

             level += 64;
             if ((level & (~127)) == 0) {
                 const int index = UNI_MPEG4_ENC_INDEX(0, run, level);

                 put_bits(ac_pb, len_tab[index], bits_tab[index]);

             } else {  // ESC3
                 put_bits(ac_pb,
                          7 + 2 + 1 + 6 + 1 + 12 + 1,
                          (3 << 23) + (3 << 21) + (0 << 20) + (run << 14) +
                          (1 << 13) + (((level - 64) & 0xfff) << 1) + 1);

             }
             last_non_zero = i;
         }
     }

     /* if (i <= last_index) */ {
         int level = block[scan_table[i]];
         int run   = i - last_non_zero - 1;
         level += 64;
         if ((level & (~127)) == 0) {
             const int index = UNI_MPEG4_ENC_INDEX(1, run, level);

             put_bits(ac_pb, len_tab[index], bits_tab[index]);

         } else {  // ESC3
             put_bits(ac_pb,
                      7 + 2 + 1 + 6 + 1 + 12 + 1,
                      (3 << 23) + (3 << 21) + (1 << 20) + (run << 14) +
                      (1 << 13) + (((level - 64) & 0xfff) << 1) + 1);

         }
     }
 }
 

 static int mpeg4_get_block_length(MpegEncContext *s,
                                   int16_t *block, int n,
                                   int intra_dc, uint8_t *scan_table)

 {
     int i, last_non_zero;
     uint8_t *len_tab;
     const int last_index = s->block_last_index[n];

     int len = 0;

     if (s->mb_intra) {  // Note gcc (3.2.1 at least) will optimize this away

         /* MPEG-4 based DC predictor */

         len += mpeg4_get_dc_length(intra_dc, n);

         if (last_index < 1)
             return len;

         i = 1;
         len_tab = uni_mpeg4_intra_rl_len;
     } else {

         if (last_index < 0)
             return 0;

         i = 0;
         len_tab = uni_mpeg4_inter_rl_len;
     }
 
     /* AC coefs */
     last_non_zero = i - 1;
     for (; i < last_index; i++) {

         int level = block[scan_table[i]];

         if (level) {
             int run = i - last_non_zero - 1;

             level += 64;
             if ((level & (~127)) == 0) {
                 const int index = UNI_MPEG4_ENC_INDEX(0, run, level);

                 len += len_tab[index];

             } else {  // ESC3
                 len += 7 + 2 + 1 + 6 + 1 + 12 + 1;

             }
             last_non_zero = i;
         }
     }

     /* if (i <= last_index) */ {
         int level = block[scan_table[i]];
         int run   = i - last_non_zero - 1;
         level += 64;
         if ((level & (~127)) == 0) {
             const int index = UNI_MPEG4_ENC_INDEX(1, run, level);

             len += len_tab[index];

         } else {  // ESC3
             len += 7 + 2 + 1 + 6 + 1 + 12 + 1;

         }
     }
 
     return len;
 }
 

 static inline void mpeg4_encode_blocks(MpegEncContext *s, int16_t block[6][64],
                                        int intra_dc[6], uint8_t **scan_table,
                                        PutBitContext *dc_pb,
                                        PutBitContext *ac_pb)
 {

     int i;
 

     if (scan_table) {

         if (s->avctx->flags2 & AV_CODEC_FLAG2_NO_OUTPUT) {

             for (i = 0; i < 6; i++)
                 skip_put_bits(&s->pb,
                               mpeg4_get_block_length(s, block[i], i,
                                                      intra_dc[i], scan_table[i]));
         } else {

             /* encode each block */

             for (i = 0; i < 6; i++)
                 mpeg4_encode_block(s, block[i], i,
                                    intra_dc[i], scan_table[i], dc_pb, ac_pb);

         }

     } else {

         if (s->avctx->flags2 & AV_CODEC_FLAG2_NO_OUTPUT) {

             for (i = 0; i < 6; i++)
                 skip_put_bits(&s->pb,
                               mpeg4_get_block_length(s, block[i], i, 0,
                                                      s->intra_scantable.permutated));
         } else {

             /* encode each block */

             for (i = 0; i < 6; i++)
                 mpeg4_encode_block(s, block[i], i, 0,
                                    s->intra_scantable.permutated, dc_pb, ac_pb);

         }
     }
 }
 

 static inline int get_b_cbp(MpegEncContext *s, int16_t block[6][64],

                             int motion_x, int motion_y, int mb_type)
 {
     int cbp = 0, i;
 

     if (s->mpv_flags & FF_MPV_FLAG_CBP_RD) {

         int score        = 0;

         const int lambda = s->lambda2 >> (FF_LAMBDA_SHIFT - 6);
 

         for (i = 0; i < 6; i++) {

             if (s->coded_score[i] < 0) {
                 score += s->coded_score[i];
                 cbp   |= 1 << (5 - i);
             }

         }

 
         if (cbp) {
             int zero_score = -6;
             if ((motion_x | motion_y | s->dquant | mb_type) == 0)

                 zero_score -= 4;  // 2 * MV + mb_type + cbp bit

 
             zero_score *= lambda;
             if (zero_score <= score)
                 cbp = 0;
         }
 
         for (i = 0; i < 6; i++) {
             if (s->block_last_index[i] >= 0 && ((cbp >> (5 - i)) & 1) == 0) {
                 s->block_last_index[i] = -1;

                 s->bdsp.clear_block(s->block[i]);

             }
         }
     } else {
         for (i = 0; i < 6; i++) {
             if (s->block_last_index[i] >= 0)
                 cbp |= 1 << (5 - i);
         }
     }
     return cbp;
 }
 

 // FIXME this is duplicated to h263.c
 static const int dquant_code[5] = { 1, 0, 9, 2, 3 };

 void ff_mpeg4_encode_mb(MpegEncContext *s, int16_t block[6][64],

                         int motion_x, int motion_y)

 {
     int cbpc, cbpy, pred_x, pred_y;

     PutBitContext *const pb2    = s->data_partitioning ? &s->pb2 : &s->pb;
     PutBitContext *const tex_pb = s->data_partitioning && s->pict_type != AV_PICTURE_TYPE_B ? &s->tex_pb : &s->pb;
     PutBitContext *const dc_pb  = s->data_partitioning && s->pict_type != AV_PICTURE_TYPE_I ? &s->pb2 : &s->pb;

     const int interleaved_stats = (s->avctx->flags & AV_CODEC_FLAG_PASS1) && !s->data_partitioning ? 1 : 0;

 
     if (!s->mb_intra) {
         int i, cbp;
 

         if (s->pict_type == AV_PICTURE_TYPE_B) {
             /* convert from mv_dir to type */
             static const int mb_type_table[8] = { -1, 3, 2, 1, -1, -1, -1, 0 };
             int mb_type = mb_type_table[s->mv_dir];
 
             if (s->mb_x == 0) {
                 for (i = 0; i < 2; i++)
                     s->last_mv[i][0][0] =
                     s->last_mv[i][0][1] =
                     s->last_mv[i][1][0] =
                     s->last_mv[i][1][1] = 0;

             }
 

             av_assert2(s->dquant >= -2 && s->dquant <= 2);
             av_assert2((s->dquant & 1) == 0);
             av_assert2(mb_type >= 0);

             /* nothing to do if this MB was skipped in the next P-frame */

             if (s->next_picture.mbskip_table[s->mb_y * s->mb_stride + s->mb_x]) {  // FIXME avoid DCT & ...

                 s->skip_count++;

                 s->mv[0][0][0] =
                 s->mv[0][0][1] =
                 s->mv[1][0][0] =
                 s->mv[1][0][1] = 0;
                 s->mv_dir  = MV_DIR_FORWARD;  // doesn't matter

                 s->qscale -= s->dquant;

 //                s->mb_skipped = 1;

 
                 return;
             }
 

             cbp = get_b_cbp(s, block, motion_x, motion_y, mb_type);

             if ((cbp | motion_x | motion_y | mb_type) == 0) {

                 /* direct MB with MV={0,0} */

                 av_assert2(s->dquant == 0);

 
                 put_bits(&s->pb, 1, 1); /* mb not coded modb1=1 */
 

                 if (interleaved_stats) {

                     s->misc_bits++;
                     s->last_bits++;
                 }
                 s->skip_count++;
                 return;
             }
 

             put_bits(&s->pb, 1, 0);            /* mb coded modb1=0 */
             put_bits(&s->pb, 1, cbp ? 0 : 1);  /* modb2 */ // FIXME merge
             put_bits(&s->pb, mb_type + 1, 1);  // this table is so simple that we don't need it :)
             if (cbp)
                 put_bits(&s->pb, 6, cbp);

             if (cbp && mb_type) {
                 if (s->dquant)
                     put_bits(&s->pb, 2, (s->dquant >> 2) + 3);

                 else
                     put_bits(&s->pb, 1, 0);

             } else

                 s->qscale -= s->dquant;
 

             if (!s->progressive_sequence) {
                 if (cbp)

                     put_bits(&s->pb, 1, s->interlaced_dct);

                 if (mb_type)                  // not direct mode

                     put_bits(&s->pb, 1, s->mv_type == MV_TYPE_FIELD);
             }
 

             if (interleaved_stats)
                 s->misc_bits += get_bits_diff(s);

             if (!mb_type) {

                 av_assert2(s->mv_dir & MV_DIRECT);

                 ff_h263_encode_motion_vector(s, motion_x, motion_y, 1);
                 s->b_count++;
                 s->f_count++;

             } else {

                 av_assert2(mb_type > 0 && mb_type < 4);

                 if (s->mv_type != MV_TYPE_FIELD) {
                     if (s->mv_dir & MV_DIR_FORWARD) {
                         ff_h263_encode_motion_vector(s,
                                                      s->mv[0][0][0] - s->last_mv[0][0][0],
                                                      s->mv[0][0][1] - s->last_mv[0][0][1],
                                                      s->f_code);
                         s->last_mv[0][0][0] =
                         s->last_mv[0][1][0] = s->mv[0][0][0];
                         s->last_mv[0][0][1] =
                         s->last_mv[0][1][1] = s->mv[0][0][1];

                         s->f_count++;
                     }

                     if (s->mv_dir & MV_DIR_BACKWARD) {
                         ff_h263_encode_motion_vector(s,
                                                      s->mv[1][0][0] - s->last_mv[1][0][0],
                                                      s->mv[1][0][1] - s->last_mv[1][0][1],
                                                      s->b_code);
                         s->last_mv[1][0][0] =
                         s->last_mv[1][1][0] = s->mv[1][0][0];
                         s->last_mv[1][0][1] =
                         s->last_mv[1][1][1] = s->mv[1][0][1];

                         s->b_count++;
                     }

                 } else {
                     if (s->mv_dir & MV_DIR_FORWARD) {

                         put_bits(&s->pb, 1, s->field_select[0][0]);
                         put_bits(&s->pb, 1, s->field_select[0][1]);
                     }

                     if (s->mv_dir & MV_DIR_BACKWARD) {

                         put_bits(&s->pb, 1, s->field_select[1][0]);
                         put_bits(&s->pb, 1, s->field_select[1][1]);
                     }

                     if (s->mv_dir & MV_DIR_FORWARD) {
                         for (i = 0; i < 2; i++) {
                             ff_h263_encode_motion_vector(s,
                                                          s->mv[0][i][0] - s->last_mv[0][i][0],
                                                          s->mv[0][i][1] - s->last_mv[0][i][1] / 2,
                                                          s->f_code);
                             s->last_mv[0][i][0] = s->mv[0][i][0];
                             s->last_mv[0][i][1] = s->mv[0][i][1] * 2;

                         }
                         s->f_count++;
                     }

                     if (s->mv_dir & MV_DIR_BACKWARD) {
                         for (i = 0; i < 2; i++) {
                             ff_h263_encode_motion_vector(s,
                                                          s->mv[1][i][0] - s->last_mv[1][i][0],
                                                          s->mv[1][i][1] - s->last_mv[1][i][1] / 2,
                                                          s->b_code);
                             s->last_mv[1][i][0] = s->mv[1][i][0];
                             s->last_mv[1][i][1] = s->mv[1][i][1] * 2;

                         }
                         s->b_count++;
                     }
                 }
             }
 

             if (interleaved_stats)
                 s->mv_bits += get_bits_diff(s);

 
             mpeg4_encode_blocks(s, block, NULL, NULL, NULL, &s->pb);
 

             if (interleaved_stats)
                 s->p_tex_bits += get_bits_diff(s);
         } else { /* s->pict_type==AV_PICTURE_TYPE_B */
             cbp = get_p_cbp(s, block, motion_x, motion_y);
 
             if ((cbp | motion_x | motion_y | s->dquant) == 0 &&
                 s->mv_type == MV_TYPE_16X16) {

                 /* Check if the B-frames can skip it too, as we must skip it

                  * if we skip here why didn't they just compress
                  * the skip-mb bits instead of reusing them ?! */
                 if (s->max_b_frames > 0) {

                     int i;

                     int x, y, offset;

                     uint8_t *p_pic;
 

                     x = s->mb_x * 16;
                     y = s->mb_y * 16;

                     offset = x + y * s->linesize;

                     p_pic  = s->new_picture.f->data[0] + offset;

                     s->mb_skipped = 1;
                     for (i = 0; i < s->max_b_frames; i++) {

                         uint8_t *b_pic;
                         int diff;

                         Picture *pic = s->reordered_input_picture[i + 1];

                         if (!pic || pic->f->pict_type != AV_PICTURE_TYPE_B)

                             break;

                         b_pic = pic->f->data[0] + offset;

                         if (!pic->shared)

                             b_pic += INPLACE_OFFSET;

 
                         if (x + 16 > s->width || y + 16 > s->height) {
                             int x1, y1;
                             int xe = FFMIN(16, s->width - x);
                             int ye = FFMIN(16, s->height - y);
                             diff = 0;
                             for (y1 = 0; y1 < ye; y1++) {
                                 for (x1 = 0; x1 < xe; x1++) {
                                     diff += FFABS(p_pic[x1 + y1 * s->linesize] - b_pic[x1 + y1 * s->linesize]);

                                 }
                             }

                             diff = diff * 256 / (xe * ye);
                         } else {

                             diff = s->mecc.sad[0](NULL, p_pic, b_pic, s->linesize, 16);

                         }

                         if (diff > s->qscale * 70) {  // FIXME check that 70 is optimal
                             s->mb_skipped = 0;

                             break;
                         }
                     }

                 } else
                     s->mb_skipped = 1;

                 if (s->mb_skipped == 1) {

                     /* skip macroblock */
                     put_bits(&s->pb, 1, 1);
 

                     if (interleaved_stats) {

                         s->misc_bits++;
                         s->last_bits++;
                     }
                     s->skip_count++;
 
                     return;
                 }
             }
 
             put_bits(&s->pb, 1, 0);     /* mb coded */

             cbpc  = cbp & 3;
             cbpy  = cbp >> 2;

             cbpy ^= 0xf;

             if (s->mv_type == MV_TYPE_16X16) {
                 if (s->dquant)
                     cbpc += 8;

                 put_bits(&s->pb,

                          ff_h263_inter_MCBPC_bits[cbpc],
                          ff_h263_inter_MCBPC_code[cbpc]);

                 put_bits(pb2, ff_h263_cbpy_tab[cbpy][1], ff_h263_cbpy_tab[cbpy][0]);

                 if (s->dquant)
                     put_bits(pb2, 2, dquant_code[s->dquant + 2]);

                 if (!s->progressive_sequence) {
                     if (cbp)

                         put_bits(pb2, 1, s->interlaced_dct);
                     put_bits(pb2, 1, 0);
                 }
 

                 if (interleaved_stats)
                     s->misc_bits += get_bits_diff(s);

 
                 /* motion vectors: 16x16 mode */

                 ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);

                 ff_h263_encode_motion_vector(s,
                                              motion_x - pred_x,
                                              motion_y - pred_y,
                                              s->f_code);
             } else if (s->mv_type == MV_TYPE_FIELD) {
                 if (s->dquant)
                     cbpc += 8;

                 put_bits(&s->pb,

                          ff_h263_inter_MCBPC_bits[cbpc],
                          ff_h263_inter_MCBPC_code[cbpc]);

                 put_bits(pb2, ff_h263_cbpy_tab[cbpy][1], ff_h263_cbpy_tab[cbpy][0]);

                 if (s->dquant)
                     put_bits(pb2, 2, dquant_code[s->dquant + 2]);

                 av_assert2(!s->progressive_sequence);

                 if (cbp)

                     put_bits(pb2, 1, s->interlaced_dct);
                 put_bits(pb2, 1, 1);
 

                 if (interleaved_stats)
                     s->misc_bits += get_bits_diff(s);

 
                 /* motion vectors: 16x8 interlaced mode */

                 ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);

                 pred_y /= 2;

 
                 put_bits(&s->pb, 1, s->field_select[0][0]);
                 put_bits(&s->pb, 1, s->field_select[0][1]);
 

                 ff_h263_encode_motion_vector(s,
                                              s->mv[0][0][0] - pred_x,
                                              s->mv[0][0][1] - pred_y,
                                              s->f_code);
                 ff_h263_encode_motion_vector(s,
                                              s->mv[0][1][0] - pred_x,
                                              s->mv[0][1][1] - pred_y,
                                              s->f_code);
             } else {

                 av_assert2(s->mv_type == MV_TYPE_8X8);

                 put_bits(&s->pb,

                          ff_h263_inter_MCBPC_bits[cbpc + 16],
                          ff_h263_inter_MCBPC_code[cbpc + 16]);

                 put_bits(pb2, ff_h263_cbpy_tab[cbpy][1], ff_h263_cbpy_tab[cbpy][0]);

                 if (!s->progressive_sequence && cbp)
                     put_bits(pb2, 1, s->interlaced_dct);

                 if (interleaved_stats)
                     s->misc_bits += get_bits_diff(s);

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

                     /* motion vectors: 8x8 mode*/

                     ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);

                     ff_h263_encode_motion_vector(s,
                                                  s->current_picture.motion_val[0][s->block_index[i]][0] - pred_x,
                                                  s->current_picture.motion_val[0][s->block_index[i]][1] - pred_y,
                                                  s->f_code);

                 }
             }
 

             if (interleaved_stats)
                 s->mv_bits += get_bits_diff(s);

 
             mpeg4_encode_blocks(s, block, NULL, NULL, NULL, tex_pb);
 

             if (interleaved_stats)
                 s->p_tex_bits += get_bits_diff(s);
 

             s->f_count++;
         }
     } else {
         int cbp;

         int dc_diff[6];  // dc values with the dc prediction subtracted
         int dir[6];      // prediction direction

         int zigzag_last_index[6];
         uint8_t *scan_table[6];
         int i;
 

         for (i = 0; i < 6; i++)
             dc_diff[i] = ff_mpeg4_pred_dc(s, i, block[i][0], &dir[i], 1);

         if (s->avctx->flags & AV_CODEC_FLAG_AC_PRED) {

             s->ac_pred = decide_ac_pred(s, block, dir, scan_table, zigzag_last_index);
         } else {
             for (i = 0; i < 6; i++)
                 scan_table[i] = s->intra_scantable.permutated;

         }
 
         /* compute cbp */
         cbp = 0;

         for (i = 0; i < 6; i++)

             if (s->block_last_index[i] >= 1)
                 cbp |= 1 << (5 - i);
 
         cbpc = cbp & 3;

         if (s->pict_type == AV_PICTURE_TYPE_I) {

             if (s->dquant)
                 cbpc += 4;

             put_bits(&s->pb,

                      ff_h263_intra_MCBPC_bits[cbpc],
                      ff_h263_intra_MCBPC_code[cbpc]);

         } else {

             if (s->dquant)
                 cbpc += 8;

             put_bits(&s->pb, 1, 0);     /* mb coded */
             put_bits(&s->pb,

                      ff_h263_inter_MCBPC_bits[cbpc + 4],
                      ff_h263_inter_MCBPC_code[cbpc + 4]);

         }
         put_bits(pb2, 1, s->ac_pred);
         cbpy = cbp >> 2;

         put_bits(pb2, ff_h263_cbpy_tab[cbpy][1], ff_h263_cbpy_tab[cbpy][0]);

         if (s->dquant)
             put_bits(dc_pb, 2, dquant_code[s->dquant + 2]);

         if (!s->progressive_sequence)

             put_bits(dc_pb, 1, s->interlaced_dct);
 

         if (interleaved_stats)
             s->misc_bits += get_bits_diff(s);

 
         mpeg4_encode_blocks(s, block, dc_diff, scan_table, dc_pb, tex_pb);
 

         if (interleaved_stats)
             s->i_tex_bits += get_bits_diff(s);

         s->i_count++;
 

         /* restore ac coeffs & last_index stuff
          * if we messed them up with the prediction */
         if (s->ac_pred)

             restore_ac_coeffs(s, block, dir, scan_table, zigzag_last_index);
     }
 }
 
 /**

  * add MPEG-4 stuffing bits (01...1)

  */

 void ff_mpeg4_stuffing(PutBitContext *pbc)

 {
     int length;
     put_bits(pbc, 1, 0);

     length = (-put_bits_count(pbc)) & 7;
     if (length)
         put_bits(pbc, length, (1 << length) - 1);

 }
 
 /* must be called before writing the header */

 void ff_set_mpeg4_time(MpegEncContext *s)
 {
     if (s->pict_type == AV_PICTURE_TYPE_B) {

         ff_mpeg4_init_direct_mv(s);

     } else {
         s->last_time_base = s->time_base;

         s->time_base      = FFUDIV(s->time, s->avctx->time_base.den);

     }
 }
 

 static void mpeg4_encode_gop_header(MpegEncContext *s)
 {

     int64_t hours, minutes, seconds;

     int64_t time;
 
     put_bits(&s->pb, 16, 0);
     put_bits(&s->pb, 16, GOP_STARTCODE);
 

     time = s->current_picture_ptr->f->pts;

     if (s->reordered_input_picture[1])

         time = FFMIN(time, s->reordered_input_picture[1]->f->pts);

     time = time * s->avctx->time_base.num;

     s->last_time_base = FFUDIV(time, s->avctx->time_base.den);

     seconds = FFUDIV(time, s->avctx->time_base.den);
     minutes = FFUDIV(seconds, 60); seconds = FFUMOD(seconds, 60);
     hours   = FFUDIV(minutes, 60); minutes = FFUMOD(minutes, 60);
     hours   = FFUMOD(hours  , 24);

 
     put_bits(&s->pb, 5, hours);
     put_bits(&s->pb, 6, minutes);
     put_bits(&s->pb, 1, 1);
     put_bits(&s->pb, 6, seconds);
 

     put_bits(&s->pb, 1, !!(s->avctx->flags & AV_CODEC_FLAG_CLOSED_GOP));

     put_bits(&s->pb, 1, 0);  // broken link == NO

 
     ff_mpeg4_stuffing(&s->pb);
 }
 

 static void mpeg4_encode_visual_object_header(MpegEncContext *s)
 {

     int profile_and_level_indication;
     int vo_ver_id;
 

     if (s->avctx->profile != FF_PROFILE_UNKNOWN) {

         profile_and_level_indication = s->avctx->profile << 4;

     } else if (s->max_b_frames || s->quarter_sample) {
         profile_and_level_indication = 0xF0;  // adv simple
     } else {
         profile_and_level_indication = 0x00;  // simple

     }
 

     if (s->avctx->level != FF_LEVEL_UNKNOWN)

         profile_and_level_indication |= s->avctx->level;

     else
         profile_and_level_indication |= 1;   // level 1

     if (profile_and_level_indication >> 4 == 0xF)
         vo_ver_id = 5;
     else
         vo_ver_id = 1;

     // FIXME levels

 
     put_bits(&s->pb, 16, 0);
     put_bits(&s->pb, 16, VOS_STARTCODE);
 
     put_bits(&s->pb, 8, profile_and_level_indication);
 
     put_bits(&s->pb, 16, 0);
     put_bits(&s->pb, 16, VISUAL_OBJ_STARTCODE);
 
     put_bits(&s->pb, 1, 1);

     put_bits(&s->pb, 4, vo_ver_id);
     put_bits(&s->pb, 3, 1);     // priority

     put_bits(&s->pb, 4, 1);     // visual obj type== video obj

     put_bits(&s->pb, 1, 0);     // video signal type == no clue // FIXME

 
     ff_mpeg4_stuffing(&s->pb);
 }
 

 static void mpeg4_encode_vol_header(MpegEncContext *s,
                                     int vo_number,
                                     int vol_number)

 {
     int vo_ver_id;
 

     if (!CONFIG_MPEG4_ENCODER)
         return;

     if (s->max_b_frames || s->quarter_sample) {
         vo_ver_id  = 5;
         s->vo_type = ADV_SIMPLE_VO_TYPE;
     } else {
         vo_ver_id  = 1;
         s->vo_type = SIMPLE_VO_TYPE;

     }
 
     put_bits(&s->pb, 16, 0);
     put_bits(&s->pb, 16, 0x100 + vo_number);        /* video obj */
     put_bits(&s->pb, 16, 0);
     put_bits(&s->pb, 16, 0x120 + vol_number);       /* video obj layer */
 
     put_bits(&s->pb, 1, 0);             /* random access vol */
     put_bits(&s->pb, 8, s->vo_type);    /* video obj type indication */

     if (s->workaround_bugs & FF_BUG_MS) {

         put_bits(&s->pb, 1, 0);         /* is obj layer id= no */
     } else {
         put_bits(&s->pb, 1, 1);         /* is obj layer id= yes */
         put_bits(&s->pb, 4, vo_ver_id); /* is obj layer ver id */
         put_bits(&s->pb, 3, 1);         /* is obj layer priority */
     }
 

     s->aspect_ratio_info = ff_h263_aspect_to_info(s->avctx->sample_aspect_ratio);

     put_bits(&s->pb, 4, s->aspect_ratio_info); /* aspect ratio info */
     if (s->aspect_ratio_info == FF_ASPECT_EXTENDED) {

         av_reduce(&s->avctx->sample_aspect_ratio.num, &s->avctx->sample_aspect_ratio.den,
                    s->avctx->sample_aspect_ratio.num,  s->avctx->sample_aspect_ratio.den, 255);

         put_bits(&s->pb, 8, s->avctx->sample_aspect_ratio.num);
         put_bits(&s->pb, 8, s->avctx->sample_aspect_ratio.den);
     }
 

     if (s->workaround_bugs & FF_BUG_MS) {

         put_bits(&s->pb, 1, 0);         /* vol control parameters= no @@@ */
     } else {
         put_bits(&s->pb, 1, 1);         /* vol control parameters= yes */
         put_bits(&s->pb, 2, 1);         /* chroma format YUV 420/YV12 */
         put_bits(&s->pb, 1, s->low_delay);
         put_bits(&s->pb, 1, 0);         /* vbv parameters= no */
     }
 
     put_bits(&s->pb, 2, RECT_SHAPE);    /* vol shape= rectangle */
     put_bits(&s->pb, 1, 1);             /* marker bit */
 
     put_bits(&s->pb, 16, s->avctx->time_base.den);
     if (s->time_increment_bits < 1)
         s->time_increment_bits = 1;
     put_bits(&s->pb, 1, 1);             /* marker bit */
     put_bits(&s->pb, 1, 0);             /* fixed vop rate=no */
     put_bits(&s->pb, 1, 1);             /* marker bit */
     put_bits(&s->pb, 13, s->width);     /* vol width */
     put_bits(&s->pb, 1, 1);             /* marker bit */
     put_bits(&s->pb, 13, s->height);    /* vol height */
     put_bits(&s->pb, 1, 1);             /* marker bit */
     put_bits(&s->pb, 1, s->progressive_sequence ? 0 : 1);
     put_bits(&s->pb, 1, 1);             /* obmc disable */

     if (vo_ver_id == 1)

         put_bits(&s->pb, 1, 0);       /* sprite enable */

     else

         put_bits(&s->pb, 2, 0);       /* sprite enable */

 
     put_bits(&s->pb, 1, 0);             /* not 8 bit == false */

     put_bits(&s->pb, 1, s->mpeg_quant); /* quant type = (0 = H.263 style) */

     if (s->mpeg_quant) {

         ff_write_quant_matrix(&s->pb, s->avctx->intra_matrix);
         ff_write_quant_matrix(&s->pb, s->avctx->inter_matrix);
     }
 
     if (vo_ver_id != 1)
         put_bits(&s->pb, 1, s->quarter_sample);
     put_bits(&s->pb, 1, 1);             /* complexity estimation disable */

     put_bits(&s->pb, 1, s->rtp_mode ? 0 : 1); /* resync marker disable */

     put_bits(&s->pb, 1, s->data_partitioning ? 1 : 0);

     if (s->data_partitioning)

         put_bits(&s->pb, 1, 0);         /* no rvlc */
 

     if (vo_ver_id != 1) {

         put_bits(&s->pb, 1, 0);         /* newpred */
         put_bits(&s->pb, 1, 0);         /* reduced res vop */
     }
     put_bits(&s->pb, 1, 0);             /* scalability */
 
     ff_mpeg4_stuffing(&s->pb);
 
     /* user data */

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

         put_bits(&s->pb, 16, 0);
         put_bits(&s->pb, 16, 0x1B2);    /* user_data */

         avpriv_put_string(&s->pb, LIBAVCODEC_IDENT, 0);

     }
 }
 

 /* write MPEG-4 VOP header */

 int ff_mpeg4_encode_picture_header(MpegEncContext *s, int picture_number)

 {

     uint64_t time_incr;
     int64_t time_div, time_mod;

     if (s->pict_type == AV_PICTURE_TYPE_I) {

         if (!(s->avctx->flags & AV_CODEC_FLAG_GLOBAL_HEADER)) {

             if (s->strict_std_compliance < FF_COMPLIANCE_VERY_STRICT)  // HACK, the reference sw is buggy

                 mpeg4_encode_visual_object_header(s);

             if (s->strict_std_compliance < FF_COMPLIANCE_VERY_STRICT || picture_number == 0)  // HACK, the reference sw is buggy

                 mpeg4_encode_vol_header(s, 0, 0);
         }

         if (!(s->workaround_bugs & FF_BUG_MS))

             mpeg4_encode_gop_header(s);
     }
 

     s->partitioned_frame = s->data_partitioning && s->pict_type != AV_PICTURE_TYPE_B;

 
     put_bits(&s->pb, 16, 0);                /* vop header */
     put_bits(&s->pb, 16, VOP_STARTCODE);    /* vop header */
     put_bits(&s->pb, 2, s->pict_type - 1);  /* pict type: I = 0 , P = 1 */
 

     time_div  = FFUDIV(s->time, s->avctx->time_base.den);
     time_mod  = FFUMOD(s->time, s->avctx->time_base.den);

     time_incr = time_div - s->last_time_base;

 
     // This limits the frame duration to max 1 hour
     if (time_incr > 3600) {

         av_log(s->avctx, AV_LOG_ERROR, "time_incr %"PRIu64" too large\n", time_incr);

         return AVERROR(EINVAL);
     }

     while (time_incr--)

         put_bits(&s->pb, 1, 1);
 
     put_bits(&s->pb, 1, 0);
 
     put_bits(&s->pb, 1, 1);                             /* marker */
     put_bits(&s->pb, s->time_increment_bits, time_mod); /* time increment */
     put_bits(&s->pb, 1, 1);                             /* marker */
     put_bits(&s->pb, 1, 1);                             /* vop coded */

     if (s->pict_type == AV_PICTURE_TYPE_P) {

         put_bits(&s->pb, 1, s->no_rounding);    /* rounding type */
     }
     put_bits(&s->pb, 3, 0);     /* intra dc VLC threshold */

     if (!s->progressive_sequence) {

         put_bits(&s->pb, 1, s->current_picture_ptr->f->top_field_first);

         put_bits(&s->pb, 1, s->alternate_scan);

     }

     // FIXME sprite stuff

 
     put_bits(&s->pb, 5, s->qscale);
 

     if (s->pict_type != AV_PICTURE_TYPE_I)

         put_bits(&s->pb, 3, s->f_code);  /* fcode_for */

     if (s->pict_type == AV_PICTURE_TYPE_B)

         put_bits(&s->pb, 3, s->b_code);  /* fcode_back */

 
     return 0;

 }
 

 static av_cold void init_uni_dc_tab(void)

 {
     int level, uni_code, uni_len;
 

     for (level = -256; level < 256; level++) {

         int size, v, l;
         /* find number of bits */
         size = 0;

         v    = abs(level);

         while (v) {
             v >>= 1;
             size++;
         }
 
         if (level < 0)

             l = (-level) ^ ((1 << size) - 1);

         else

             l = level;

 
         /* luminance */

         uni_code = ff_mpeg4_DCtab_lum[size][0];
         uni_len  = ff_mpeg4_DCtab_lum[size][1];

 
         if (size > 0) {

             uni_code <<= size;
             uni_code  |= l;
             uni_len   += size;
             if (size > 8) {
                 uni_code <<= 1;
                 uni_code  |= 1;

                 uni_len++;
             }
         }

         uni_DCtab_lum_bits[level + 256] = uni_code;
         uni_DCtab_lum_len[level + 256]  = uni_len;

 
         /* chrominance */

         uni_code = ff_mpeg4_DCtab_chrom[size][0];
         uni_len  = ff_mpeg4_DCtab_chrom[size][1];

 
         if (size > 0) {

             uni_code <<= size;
             uni_code  |= l;
             uni_len   += size;
             if (size > 8) {
                 uni_code <<= 1;
                 uni_code  |= 1;

                 uni_len++;
             }
         }

         uni_DCtab_chrom_bits[level + 256] = uni_code;
         uni_DCtab_chrom_len[level + 256]  = uni_len;

     }
 }
 

 static av_cold void init_uni_mpeg4_rl_tab(RLTable *rl, uint32_t *bits_tab,
                                           uint8_t *len_tab)
 {

     int slevel, run, last;
 

     av_assert0(MAX_LEVEL >= 64);

     av_assert0(MAX_RUN >= 63);

 
     for (slevel = -64; slevel < 64; slevel++) {
         if (slevel == 0)
             continue;
         for (run = 0; run < 64; run++) {
             for (last = 0; last <= 1; last++) {
                 const int index = UNI_MPEG4_ENC_INDEX(last, run, slevel + 64);
                 int level       = slevel < 0 ? -slevel : slevel;
                 int sign        = slevel < 0 ? 1 : 0;

                 int bits, len, code;
                 int level1, run1;
 

                 len_tab[index] = 100;

 
                 /* ESC0 */

                 code = get_rl_index(rl, last, run, level);
                 bits = rl->table_vlc[code][0];
                 len  = rl->table_vlc[code][1];
                 bits = bits * 2 + sign;
                 len++;
 
                 if (code != rl->n && len < len_tab[index]) {
                     bits_tab[index] = bits;
                     len_tab[index]  = len;

                 }
                 /* ESC1 */

                 bits = rl->table_vlc[rl->n][0];
                 len  = rl->table_vlc[rl->n][1];
                 bits = bits * 2;
                 len++;                 // esc1
                 level1 = level - rl->max_level[last][run];
                 if (level1 > 0) {
                     code   = get_rl_index(rl, last, run, level1);
                     bits <<= rl->table_vlc[code][1];
                     len   += rl->table_vlc[code][1];
                     bits  += rl->table_vlc[code][0];
                     bits   = bits * 2 + sign;
                     len++;
 
                     if (code != rl->n && len < len_tab[index]) {
                         bits_tab[index] = bits;
                         len_tab[index]  = len;

                     }
                 }
                 /* ESC2 */

                 bits = rl->table_vlc[rl->n][0];
                 len  = rl->table_vlc[rl->n][1];
                 bits = bits * 4 + 2;
                 len += 2;                 // esc2

                 run1 = run - rl->max_run[last][level] - 1;

                 if (run1 >= 0) {
                     code   = get_rl_index(rl, last, run1, level);
                     bits <<= rl->table_vlc[code][1];
                     len   += rl->table_vlc[code][1];
                     bits  += rl->table_vlc[code][0];
                     bits   = bits * 2 + sign;
                     len++;
 
                     if (code != rl->n && len < len_tab[index]) {
                         bits_tab[index] = bits;
                         len_tab[index]  = len;

                     }
                 }
                 /* ESC3 */

                 bits = rl->table_vlc[rl->n][0];
                 len  = rl->table_vlc[rl->n][1];
                 bits = bits * 4 + 3;
                 len += 2;                 // esc3
                 bits = bits * 2 + last;
                 len++;
                 bits = bits * 64 + run;
                 len += 6;
                 bits = bits * 2 + 1;
                 len++;                    // marker
                 bits = bits * 4096 + (slevel & 0xfff);
                 len += 12;
                 bits = bits * 2 + 1;
                 len++;                    // marker
 
                 if (len < len_tab[index]) {
                     bits_tab[index] = bits;
                     len_tab[index]  = len;

                 }
             }
         }
     }
 }
 
 static av_cold int encode_init(AVCodecContext *avctx)
 {
     MpegEncContext *s = avctx->priv_data;
     int ret;
     static int done = 0;
 

     if (avctx->width >= (1<<13) || avctx->height >= (1<<13)) {
         av_log(avctx, AV_LOG_ERROR, "dimensions too large for MPEG-4\n");
         return AVERROR(EINVAL);
     }
 

     if ((ret = ff_mpv_encode_init(avctx)) < 0)

         return ret;
 
     if (!done) {
         done = 1;
 
         init_uni_dc_tab();
 

         ff_rl_init(&ff_mpeg4_rl_intra, ff_mpeg4_static_rl_table_store[0]);

         init_uni_mpeg4_rl_tab(&ff_mpeg4_rl_intra, uni_mpeg4_intra_rl_bits, uni_mpeg4_intra_rl_len);

         init_uni_mpeg4_rl_tab(&ff_h263_rl_inter, uni_mpeg4_inter_rl_bits, uni_mpeg4_inter_rl_len);

     }
 

     s->min_qcoeff               = -2048;
     s->max_qcoeff               = 2047;
     s->intra_ac_vlc_length      = uni_mpeg4_intra_rl_len;
     s->intra_ac_vlc_last_length = uni_mpeg4_intra_rl_len + 128 * 64;
     s->inter_ac_vlc_length      = uni_mpeg4_inter_rl_len;
     s->inter_ac_vlc_last_length = uni_mpeg4_inter_rl_len + 128 * 64;
     s->luma_dc_vlc_length       = uni_DCtab_lum_len;
     s->ac_esc_length            = 7 + 2 + 1 + 6 + 1 + 12 + 1;
     s->y_dc_scale_table         = ff_mpeg4_y_dc_scale_table;
     s->c_dc_scale_table         = ff_mpeg4_c_dc_scale_table;
 

     if (s->avctx->flags & AV_CODEC_FLAG_GLOBAL_HEADER) {

         s->avctx->extradata = av_malloc(1024);

         init_put_bits(&s->pb, s->avctx->extradata, 1024);
 

         if (!(s->workaround_bugs & FF_BUG_MS))

             mpeg4_encode_visual_object_header(s);
         mpeg4_encode_vol_header(s, 0, 0);
 
 //            ff_mpeg4_stuffing(&s->pb); ?
         flush_put_bits(&s->pb);

         s->avctx->extradata_size = (put_bits_count(&s->pb) + 7) >> 3;

     }
     return 0;
 }
 
 void ff_mpeg4_init_partitions(MpegEncContext *s)
 {

     uint8_t *start = put_bits_ptr(&s->pb);
     uint8_t *end   = s->pb.buf_end;
     int size       = end - start;
     int pb_size    = (((intptr_t)start + size / 3) & (~3)) - (intptr_t)start;
     int tex_size   = (size - 2 * pb_size) & (~3);

 
     set_put_bits_buffer_size(&s->pb, pb_size);

     init_put_bits(&s->tex_pb, start + pb_size, tex_size);
     init_put_bits(&s->pb2, start + pb_size + tex_size, pb_size);

 }
 
 void ff_mpeg4_merge_partitions(MpegEncContext *s)
 {

     const int pb2_len    = put_bits_count(&s->pb2);
     const int tex_pb_len = put_bits_count(&s->tex_pb);
     const int bits       = put_bits_count(&s->pb);

     if (s->pict_type == AV_PICTURE_TYPE_I) {

         put_bits(&s->pb, 19, DC_MARKER);

         s->misc_bits  += 19 + pb2_len + bits - s->last_bits;
         s->i_tex_bits += tex_pb_len;
     } else {

         put_bits(&s->pb, 17, MOTION_MARKER);

         s->misc_bits  += 17 + pb2_len;
         s->mv_bits    += bits - s->last_bits;
         s->p_tex_bits += tex_pb_len;

     }
 
     flush_put_bits(&s->pb2);
     flush_put_bits(&s->tex_pb);
 
     set_put_bits_buffer_size(&s->pb, s->pb2.buf_end - s->pb.buf);

     avpriv_copy_bits(&s->pb, s->pb2.buf, pb2_len);

     avpriv_copy_bits(&s->pb, s->tex_pb.buf, tex_pb_len);

     s->last_bits = put_bits_count(&s->pb);

 }
 
 void ff_mpeg4_encode_video_packet_header(MpegEncContext *s)
 {

     int mb_num_bits = av_log2(s->mb_num - 1) + 1;

 
     put_bits(&s->pb, ff_mpeg4_get_video_packet_prefix_length(s), 0);
     put_bits(&s->pb, 1, 1);
 

     put_bits(&s->pb, mb_num_bits, s->mb_x + s->mb_y * s->mb_width);

     put_bits(&s->pb, s->quant_precision, s->qscale);
     put_bits(&s->pb, 1, 0); /* no HEC */
 }
 

 #define OFFSET(x) offsetof(MpegEncContext, x)
 #define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
 static const AVOption options[] = {

     { "data_partitioning", "Use data partitioning.",      OFFSET(data_partitioning), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, VE },
     { "alternate_scan",    "Enable alternate scantable.", OFFSET(alternate_scan),    AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, VE },

     FF_MPV_COMMON_OPTS

     { NULL },
 };
 
 static const AVClass mpeg4enc_class = {
     .class_name = "MPEG4 encoder",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,
 };
 

 AVCodec ff_mpeg4_encoder = {

     .name           = "mpeg4",

     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2"),

     .type           = AVMEDIA_TYPE_VIDEO,

     .id             = AV_CODEC_ID_MPEG4,

     .priv_data_size = sizeof(MpegEncContext),
     .init           = encode_init,

     .encode2        = ff_mpv_encode_picture,
     .close          = ff_mpv_encode_end,

     .pix_fmts       = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE },

     .capabilities   = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS,

     .priv_class     = &mpeg4enc_class,

 };