/*
  * MSMPEG4 encoder backend
  * Copyright (c) 2001 Fabrice Bellard
  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
  *
  * msmpeg4v1 & v2 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
  * MSMPEG4 encoder backend
  */
 
 #include <stdint.h>
 #include <string.h>
 

 #include "libavutil/attributes.h"

 #include "libavutil/avutil.h"
 #include "libavutil/mem.h"
 #include "mpegvideo.h"
 #include "h263.h"

 #include "internal.h"

 #include "mpeg4video.h"
 #include "msmpeg4.h"
 #include "msmpeg4data.h"
 #include "put_bits.h"
 #include "rl.h"
 #include "vc1data.h"
 
 static uint8_t rl_length[NB_RL_TABLES][MAX_LEVEL+1][MAX_RUN+1][2];
 
 /* build the table which associate a (x,y) motion vector to a vlc */

 static av_cold int init_mv_table(MVTable *tab)

 {
     int i, x, y;
 
     tab->table_mv_index = av_malloc(sizeof(uint16_t) * 4096);

     if (!tab->table_mv_index)
         return AVERROR(ENOMEM);
 

     /* mark all entries as not used */
     for(i=0;i<4096;i++)
         tab->table_mv_index[i] = tab->n;
 
     for(i=0;i<tab->n;i++) {
         x = tab->table_mvx[i];
         y = tab->table_mvy[i];
         tab->table_mv_index[(x << 6) | y] = i;
     }

 
     return 0;

 }
 
 void ff_msmpeg4_code012(PutBitContext *pb, int n)
 {
     if (n == 0) {
         put_bits(pb, 1, 0);
     } else {
         put_bits(pb, 1, 1);
         put_bits(pb, 1, (n >= 2));
     }
 }
 
 static int get_size_of_code(MpegEncContext * s, RLTable *rl, int last, int run, int level, int intra){
     int size=0;
     int code;
     int run_diff= intra ? 0 : 1;
 
     code = get_rl_index(rl, last, run, level);
     size+= rl->table_vlc[code][1];
     if (code == rl->n) {
         int level1, run1;
 
         level1 = level - rl->max_level[last][run];
         if (level1 < 1)
             goto esc2;
         code = get_rl_index(rl, last, run, level1);
         if (code == rl->n) {
             esc2:
             size++;
             if (level > MAX_LEVEL)
                 goto esc3;
             run1 = run - rl->max_run[last][level] - run_diff;
             if (run1 < 0)
                 goto esc3;
             code = get_rl_index(rl, last, run1, level);
             if (code == rl->n) {
             esc3:
                 /* third escape */
                 size+=1+1+6+8;
             } else {
                 /* second escape */
                 size+= 1+1+ rl->table_vlc[code][1];
             }
         } else {
             /* first escape */
             size+= 1+1+ rl->table_vlc[code][1];
         }
     } else {
         size++;
     }
     return size;
 }
 

 av_cold int ff_msmpeg4_encode_init(MpegEncContext *s)

 {
     static int init_done=0;

     int i, ret;

 
     ff_msmpeg4_common_init(s);
     if(s->msmpeg4_version>=4){
         s->min_qcoeff= -255;
         s->max_qcoeff=  255;
     }
 
     if (!init_done) {
         /* init various encoding tables */
         init_done = 1;

         if ((ret = init_mv_table(&ff_mv_tables[0])) < 0)
             return ret;
         if ((ret = init_mv_table(&ff_mv_tables[1])) < 0)
             return ret;

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

             ff_rl_init(&ff_rl_table[i], ff_static_rl_table_store[i]);

 
         for(i=0; i<NB_RL_TABLES; i++){
             int level;
             for (level = 1; level <= MAX_LEVEL; level++) {
                 int run;
                 for(run=0; run<=MAX_RUN; run++){
                     int last;
                     for(last=0; last<2; last++){
                         rl_length[i][level][run][last]= get_size_of_code(s, &ff_rl_table[  i], last, run, level, 0);
                     }
                 }
             }
         }
     }

 
     return 0;

 }
 
 static void find_best_tables(MpegEncContext * s)
 {
     int i;

     int best        = 0, best_size        = INT_MAX;
     int chroma_best = 0, best_chroma_size = INT_MAX;

 
     for(i=0; i<3; i++){
         int level;
         int chroma_size=0;
         int size=0;
 
         if(i>0){// ;)
             size++;
             chroma_size++;
         }
         for(level=0; level<=MAX_LEVEL; level++){
             int run;
             for(run=0; run<=MAX_RUN; run++){
                 int last;
                 const int last_size= size + chroma_size;
                 for(last=0; last<2; last++){
                     int inter_count       = s->ac_stats[0][0][level][run][last] + s->ac_stats[0][1][level][run][last];
                     int intra_luma_count  = s->ac_stats[1][0][level][run][last];
                     int intra_chroma_count= s->ac_stats[1][1][level][run][last];
 
                     if(s->pict_type==AV_PICTURE_TYPE_I){
                         size       += intra_luma_count  *rl_length[i  ][level][run][last];
                         chroma_size+= intra_chroma_count*rl_length[i+3][level][run][last];
                     }else{
                         size+=        intra_luma_count  *rl_length[i  ][level][run][last]
                                      +intra_chroma_count*rl_length[i+3][level][run][last]
                                      +inter_count       *rl_length[i+3][level][run][last];
                     }
                 }
                 if(last_size == size+chroma_size) break;
             }
         }
         if(size<best_size){
             best_size= size;
             best= i;
         }
         if(chroma_size<best_chroma_size){
             best_chroma_size= chroma_size;
             chroma_best= i;
         }
     }
 
     if(s->pict_type==AV_PICTURE_TYPE_P) chroma_best= best;
 
     memset(s->ac_stats, 0, sizeof(int)*(MAX_LEVEL+1)*(MAX_RUN+1)*2*2*2);
 
     s->rl_table_index       =        best;
     s->rl_chroma_table_index= chroma_best;
 
     if(s->pict_type != s->last_non_b_pict_type){
         s->rl_table_index= 2;
         if(s->pict_type==AV_PICTURE_TYPE_I)
             s->rl_chroma_table_index= 1;
         else
             s->rl_chroma_table_index= 2;
     }
 
 }
 
 /* write MSMPEG4 compatible frame header */
 void ff_msmpeg4_encode_picture_header(MpegEncContext * s, int picture_number)
 {
     find_best_tables(s);
 
     avpriv_align_put_bits(&s->pb);
     put_bits(&s->pb, 2, s->pict_type - 1);
 
     put_bits(&s->pb, 5, s->qscale);
     if(s->msmpeg4_version<=2){
         s->rl_table_index = 2;
         s->rl_chroma_table_index = 2;
     }
 
     s->dc_table_index = 1;
     s->mv_table_index = 1; /* only if P frame */
     s->use_skip_mb_code = 1; /* only if P frame */
     s->per_mb_rl_table = 0;
     if(s->msmpeg4_version==4)
         s->inter_intra_pred= (s->width*s->height < 320*240 && s->bit_rate<=II_BITRATE && s->pict_type==AV_PICTURE_TYPE_P);

     ff_dlog(s, "%d %"PRId64" %d %d %d\n", s->pict_type, s->bit_rate,

             s->inter_intra_pred, s->width, s->height);

 
     if (s->pict_type == AV_PICTURE_TYPE_I) {
         s->slice_height= s->mb_height/1;
         put_bits(&s->pb, 5, 0x16 + s->mb_height/s->slice_height);
 
         if(s->msmpeg4_version==4){
             ff_msmpeg4_encode_ext_header(s);
             if(s->bit_rate>MBAC_BITRATE)
                 put_bits(&s->pb, 1, s->per_mb_rl_table);
         }
 
         if(s->msmpeg4_version>2){
             if(!s->per_mb_rl_table){
                 ff_msmpeg4_code012(&s->pb, s->rl_chroma_table_index);
                 ff_msmpeg4_code012(&s->pb, s->rl_table_index);
             }
 
             put_bits(&s->pb, 1, s->dc_table_index);
         }
     } else {
         put_bits(&s->pb, 1, s->use_skip_mb_code);
 
         if(s->msmpeg4_version==4 && s->bit_rate>MBAC_BITRATE)
             put_bits(&s->pb, 1, s->per_mb_rl_table);
 
         if(s->msmpeg4_version>2){
             if(!s->per_mb_rl_table)
                 ff_msmpeg4_code012(&s->pb, s->rl_table_index);
 
             put_bits(&s->pb, 1, s->dc_table_index);
 
             put_bits(&s->pb, 1, s->mv_table_index);
         }
     }
 
     s->esc3_level_length= 0;
     s->esc3_run_length= 0;
 }
 
 void ff_msmpeg4_encode_ext_header(MpegEncContext * s)
 {

         unsigned fps = s->avctx->time_base.den / s->avctx->time_base.num / FFMAX(s->avctx->ticks_per_frame, 1);
         put_bits(&s->pb, 5, FFMIN(fps, 31)); //yes 29.97 -> 29

 
         put_bits(&s->pb, 11, FFMIN(s->bit_rate/1024, 2047));
 
         if(s->msmpeg4_version>=3)
             put_bits(&s->pb, 1, s->flipflop_rounding);
         else

             av_assert0(s->flipflop_rounding==0);

 }
 
 void ff_msmpeg4_encode_motion(MpegEncContext * s,
                                   int mx, int my)
 {
     int code;
     MVTable *mv;
 
     /* modulo encoding */
     /* WARNING : you cannot reach all the MVs even with the modulo
        encoding. This is a somewhat strange compromise they took !!!  */
     if (mx <= -64)
         mx += 64;
     else if (mx >= 64)
         mx -= 64;
     if (my <= -64)
         my += 64;
     else if (my >= 64)
         my -= 64;
 
     mx += 32;
     my += 32;
 #if 0
     if ((unsigned)mx >= 64 ||
         (unsigned)my >= 64)
         av_log(s->avctx, AV_LOG_ERROR, "error mx=%d my=%d\n", mx, my);
 #endif
     mv = &ff_mv_tables[s->mv_table_index];
 
     code = mv->table_mv_index[(mx << 6) | my];
     put_bits(&s->pb,
              mv->table_mv_bits[code],
              mv->table_mv_code[code]);
     if (code == mv->n) {
         /* escape : code literally */
         put_bits(&s->pb, 6, mx);
         put_bits(&s->pb, 6, my);
     }
 }
 
 void ff_msmpeg4_handle_slices(MpegEncContext *s){
     if (s->mb_x == 0) {
         if (s->slice_height && (s->mb_y % s->slice_height) == 0) {
             if(s->msmpeg4_version < 4){
                 ff_mpeg4_clean_buffers(s);
             }
             s->first_slice_line = 1;
         } else {
             s->first_slice_line = 0;
         }
     }
 }
 
 static void msmpeg4v2_encode_motion(MpegEncContext * s, int val)
 {
     int range, bit_size, sign, code, bits;
 
     if (val == 0) {
         /* zero vector */
         code = 0;
         put_bits(&s->pb, ff_mvtab[code][1], ff_mvtab[code][0]);
     } else {
         bit_size = s->f_code - 1;
         range = 1 << bit_size;
         if (val <= -64)
             val += 64;
         else if (val >= 64)
             val -= 64;
 
         if (val >= 0) {
             sign = 0;
         } else {
             val = -val;
             sign = 1;
         }
         val--;
         code = (val >> bit_size) + 1;
         bits = val & (range - 1);
 
         put_bits(&s->pb, ff_mvtab[code][1] + 1, (ff_mvtab[code][0] << 1) | sign);
         if (bit_size > 0) {
             put_bits(&s->pb, bit_size, bits);
         }
     }
 }
 
 void ff_msmpeg4_encode_mb(MpegEncContext * s,

                           int16_t block[6][64],

                           int motion_x, int motion_y)
 {
     int cbp, coded_cbp, i;
     int pred_x, pred_y;
     uint8_t *coded_block;
 
     ff_msmpeg4_handle_slices(s);
 
     if (!s->mb_intra) {
         /* compute cbp */
         cbp = 0;
         for (i = 0; i < 6; i++) {
             if (s->block_last_index[i] >= 0)
                 cbp |= 1 << (5 - i);
         }
         if (s->use_skip_mb_code && (cbp | motion_x | motion_y) == 0) {
             /* skip macroblock */
             put_bits(&s->pb, 1, 1);
             s->last_bits++;
             s->misc_bits++;
             s->skip_count++;
 
             return;
         }
         if (s->use_skip_mb_code)
             put_bits(&s->pb, 1, 0);     /* mb coded */
 
         if(s->msmpeg4_version<=2){
             put_bits(&s->pb,
                      ff_v2_mb_type[cbp&3][1],
                      ff_v2_mb_type[cbp&3][0]);
             if((cbp&3) != 3) coded_cbp= cbp ^ 0x3C;
             else             coded_cbp= cbp;
 
             put_bits(&s->pb,
                      ff_h263_cbpy_tab[coded_cbp>>2][1],
                      ff_h263_cbpy_tab[coded_cbp>>2][0]);
 
             s->misc_bits += get_bits_diff(s);
 
             ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
             msmpeg4v2_encode_motion(s, motion_x - pred_x);
             msmpeg4v2_encode_motion(s, motion_y - pred_y);
         }else{
             put_bits(&s->pb,
                      ff_table_mb_non_intra[cbp + 64][1],
                      ff_table_mb_non_intra[cbp + 64][0]);
 
             s->misc_bits += get_bits_diff(s);
 
             /* motion vector */
             ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
             ff_msmpeg4_encode_motion(s, motion_x - pred_x,
                                   motion_y - pred_y);
         }
 
         s->mv_bits += get_bits_diff(s);
 
         for (i = 0; i < 6; i++) {
             ff_msmpeg4_encode_block(s, block[i], i);
         }
         s->p_tex_bits += get_bits_diff(s);
     } else {
         /* compute cbp */
         cbp = 0;
         coded_cbp = 0;
         for (i = 0; i < 6; i++) {
             int val, pred;
             val = (s->block_last_index[i] >= 1);
             cbp |= val << (5 - i);
             if (i < 4) {
                 /* predict value for close blocks only for luma */
                 pred = ff_msmpeg4_coded_block_pred(s, i, &coded_block);
                 *coded_block = val;
                 val = val ^ pred;
             }
             coded_cbp |= val << (5 - i);
         }
 
         if(s->msmpeg4_version<=2){
             if (s->pict_type == AV_PICTURE_TYPE_I) {
                 put_bits(&s->pb,
                          ff_v2_intra_cbpc[cbp&3][1], ff_v2_intra_cbpc[cbp&3][0]);
             } else {
                 if (s->use_skip_mb_code)
                     put_bits(&s->pb, 1, 0);     /* mb coded */
                 put_bits(&s->pb,
                          ff_v2_mb_type[(cbp&3) + 4][1],
                          ff_v2_mb_type[(cbp&3) + 4][0]);
             }
             put_bits(&s->pb, 1, 0);             /* no AC prediction yet */
             put_bits(&s->pb,
                      ff_h263_cbpy_tab[cbp>>2][1],
                      ff_h263_cbpy_tab[cbp>>2][0]);
         }else{
             if (s->pict_type == AV_PICTURE_TYPE_I) {
                 put_bits(&s->pb,
                          ff_msmp4_mb_i_table[coded_cbp][1], ff_msmp4_mb_i_table[coded_cbp][0]);
             } else {
                 if (s->use_skip_mb_code)
                     put_bits(&s->pb, 1, 0);     /* mb coded */
                 put_bits(&s->pb,
                          ff_table_mb_non_intra[cbp][1],
                          ff_table_mb_non_intra[cbp][0]);
             }
             put_bits(&s->pb, 1, 0);             /* no AC prediction yet */
             if(s->inter_intra_pred){
                 s->h263_aic_dir=0;
                 put_bits(&s->pb, ff_table_inter_intra[s->h263_aic_dir][1], ff_table_inter_intra[s->h263_aic_dir][0]);
             }
         }
         s->misc_bits += get_bits_diff(s);
 
         for (i = 0; i < 6; i++) {
             ff_msmpeg4_encode_block(s, block[i], i);
         }
         s->i_tex_bits += get_bits_diff(s);
         s->i_count++;
     }
 }
 
 static void msmpeg4_encode_dc(MpegEncContext * s, int level, int n, int *dir_ptr)
 {
     int sign, code;

     int pred, av_uninit(extquant);

     int extrabits = 0;
 
     int16_t *dc_val;
     pred = ff_msmpeg4_pred_dc(s, n, &dc_val, dir_ptr);
 
     /* update predictor */
     if (n < 4) {
         *dc_val = level * s->y_dc_scale;
     } else {
         *dc_val = level * s->c_dc_scale;
     }
 
     /* do the prediction */
     level -= pred;
 
     if(s->msmpeg4_version<=2){
         if (n < 4) {
             put_bits(&s->pb,
                      ff_v2_dc_lum_table[level + 256][1],
                      ff_v2_dc_lum_table[level + 256][0]);
         }else{
             put_bits(&s->pb,
                      ff_v2_dc_chroma_table[level + 256][1],
                      ff_v2_dc_chroma_table[level + 256][0]);
         }
     }else{
         sign = 0;
         if (level < 0) {
             level = -level;
             sign = 1;
         }
         code = level;
         if (code > DC_MAX)
             code = DC_MAX;
         else if( s->msmpeg4_version>=6 ) {
             if( s->qscale == 1 ) {
                 extquant = (level + 3) & 0x3;
                 code  = ((level+3)>>2);
             } else if( s->qscale == 2 ) {
                 extquant = (level + 1) & 0x1;
                 code  = ((level+1)>>1);
             }
         }
 
         if (s->dc_table_index == 0) {
             if (n < 4) {
                 put_bits(&s->pb, ff_table0_dc_lum[code][1], ff_table0_dc_lum[code][0]);
             } else {
                 put_bits(&s->pb, ff_table0_dc_chroma[code][1], ff_table0_dc_chroma[code][0]);
             }
         } else {
             if (n < 4) {
                 put_bits(&s->pb, ff_table1_dc_lum[code][1], ff_table1_dc_lum[code][0]);
             } else {
                 put_bits(&s->pb, ff_table1_dc_chroma[code][1], ff_table1_dc_chroma[code][0]);
             }
         }
 
         if(s->msmpeg4_version>=6 && s->qscale<=2)
             extrabits = 3 - s->qscale;
 
         if (code == DC_MAX)
             put_bits(&s->pb, 8 + extrabits, level);
         else if(extrabits > 0)//== VC1 && s->qscale<=2
             put_bits(&s->pb, extrabits, extquant);
 
         if (level != 0) {
             put_bits(&s->pb, 1, sign);
         }
     }
 }
 
 /* Encoding of a block. Very similar to MPEG4 except for a different
    escape coding (same as H263) and more vlc tables.
  */

 void ff_msmpeg4_encode_block(MpegEncContext * s, int16_t * block, int n)

 {
     int level, run, last, i, j, last_index;
     int last_non_zero, sign, slevel;
     int code, run_diff, dc_pred_dir;
     const RLTable *rl;
     const uint8_t *scantable;
 
     if (s->mb_intra) {
         msmpeg4_encode_dc(s, block[0], n, &dc_pred_dir);
         i = 1;
         if (n < 4) {
             rl = &ff_rl_table[s->rl_table_index];
         } else {
             rl = &ff_rl_table[3 + s->rl_chroma_table_index];
         }
         run_diff = s->msmpeg4_version>=4;
         scantable= s->intra_scantable.permutated;
     } else {
         i = 0;
         rl = &ff_rl_table[3 + s->rl_table_index];
         if(s->msmpeg4_version<=2)
             run_diff = 0;
         else
             run_diff = 1;
         scantable= s->inter_scantable.permutated;
     }
 
     /* recalculate block_last_index for M$ wmv1 */
     if(s->msmpeg4_version>=4 && s->msmpeg4_version<6 && s->block_last_index[n]>0){
         for(last_index=63; last_index>=0; last_index--){
             if(block[scantable[last_index]]) break;
         }
         s->block_last_index[n]= last_index;
     }else
         last_index = s->block_last_index[n];
     /* AC coefs */
     last_non_zero = i - 1;
     for (; i <= last_index; i++) {
         j = scantable[i];
         level = block[j];
         if (level) {
             run = i - last_non_zero - 1;
             last = (i == last_index);
             sign = 0;
             slevel = level;
             if (level < 0) {
                 sign = 1;
                 level = -level;
             }
 
             if(level<=MAX_LEVEL && run<=MAX_RUN){
                 s->ac_stats[s->mb_intra][n>3][level][run][last]++;
             }
 
             s->ac_stats[s->mb_intra][n > 3][40][63][0]++; //esc3 like
 
             code = get_rl_index(rl, last, run, level);
             put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
             if (code == rl->n) {
                 int level1, run1;
 
                 level1 = level - rl->max_level[last][run];
                 if (level1 < 1)
                     goto esc2;
                 code = get_rl_index(rl, last, run, level1);
                 if (code == rl->n) {
                 esc2:
                     put_bits(&s->pb, 1, 0);
                     if (level > MAX_LEVEL)
                         goto esc3;
                     run1 = run - rl->max_run[last][level] - run_diff;
                     if (run1 < 0)
                         goto esc3;
                     code = get_rl_index(rl, last, run1+1, level);
                     if (s->msmpeg4_version == 4 && code == rl->n)
                         goto esc3;
                     code = get_rl_index(rl, last, run1, level);
                     if (code == rl->n) {
                     esc3:
                         /* third escape */
                         put_bits(&s->pb, 1, 0);
                         put_bits(&s->pb, 1, last);
                         if(s->msmpeg4_version>=4){
                             if(s->esc3_level_length==0){
                                 s->esc3_level_length=8;
                                 s->esc3_run_length= 6;
                                 //ESCLVLSZ + ESCRUNSZ
                                 if(s->qscale<8)
                                     put_bits(&s->pb, 6 + (s->msmpeg4_version>=6), 3);
                                 else
                                     put_bits(&s->pb, 8, 3);
                             }
                             put_bits(&s->pb, s->esc3_run_length, run);
                             put_bits(&s->pb, 1, sign);
                             put_bits(&s->pb, s->esc3_level_length, level);
                         }else{
                             put_bits(&s->pb, 6, run);
                             put_sbits(&s->pb, 8, slevel);
                         }
                     } else {
                         /* second escape */
                         put_bits(&s->pb, 1, 1);
                         put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
                         put_bits(&s->pb, 1, sign);
                     }
                 } else {
                     /* first escape */
                     put_bits(&s->pb, 1, 1);
                     put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
                     put_bits(&s->pb, 1, sign);
                 }
             } else {
                 put_bits(&s->pb, 1, sign);
             }
             last_non_zero = i;
         }
     }
 }