/*
  * MSMPEG4 backend for encoder and decoder
  * Copyright (c) 2001 Fabrice Bellard

  * Copyright (c) 2002-2013 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
  */
 
 #include "avcodec.h"

 #include "internal.h"

 #include "mpegutils.h"

 #include "mpegvideo.h"
 #include "msmpeg4.h"

 #include "libavutil/imgutils.h"

 #include "libavutil/x86/asm.h"
 #include "h263.h"
 #include "mpeg4video.h"
 #include "msmpeg4data.h"
 #include "vc1data.h"

 #include "wmv2.h"

 
 #define DC_VLC_BITS 9
 #define V2_INTRA_CBPC_VLC_BITS 3
 #define V2_MB_TYPE_VLC_BITS 7
 #define MV_VLC_BITS 9
 #define V2_MV_VLC_BITS 9
 #define TEX_VLC_BITS 9
 
 #define DEFAULT_INTER_INDEX 3
 
 static inline int msmpeg4v1_pred_dc(MpegEncContext * s, int n,
                                     int32_t **dc_val_ptr)
 {
     int i;
 
     if (n < 4) {
         i= 0;
     } else {
         i= n-3;
     }
 
     *dc_val_ptr= &s->last_dc[i];
     return s->last_dc[i];
 }
 
 /****************************************/
 /* decoding stuff */
 
 VLC ff_mb_non_intra_vlc[4];
 static VLC v2_dc_lum_vlc;
 static VLC v2_dc_chroma_vlc;
 static VLC v2_intra_cbpc_vlc;
 static VLC v2_mb_type_vlc;
 static VLC v2_mv_vlc;
 VLC ff_inter_intra_vlc;
 
 /* This is identical to h263 except that its range is multiplied by 2. */
 static int msmpeg4v2_decode_motion(MpegEncContext * s, int pred, int f_code)
 {
     int code, val, sign, shift;
 
     code = get_vlc2(&s->gb, v2_mv_vlc.table, V2_MV_VLC_BITS, 2);

     ff_dlog(s, "MV code %d at %d %d pred: %d\n", code, s->mb_x,s->mb_y, pred);

     if (code < 0)
         return 0xffff;
 
     if (code == 0)
         return pred;
     sign = get_bits1(&s->gb);
     shift = f_code - 1;
     val = code;
     if (shift) {
         val = (val - 1) << shift;
         val |= get_bits(&s->gb, shift);
         val++;
     }
     if (sign)
         val = -val;
 
     val += pred;
     if (val <= -64)
         val += 64;
     else if (val >= 64)
         val -= 64;
 
     return val;
 }
 
 static int msmpeg4v12_decode_mb(MpegEncContext *s, int16_t block[6][64])
 {
     int cbp, code, i;

     uint32_t * const mb_type_ptr = &s->current_picture.mb_type[s->mb_x + s->mb_y*s->mb_stride];

 
     if (s->pict_type == AV_PICTURE_TYPE_P) {
         if (s->use_skip_mb_code) {
             if (get_bits1(&s->gb)) {
                 /* skip mb */
                 s->mb_intra = 0;
                 for(i=0;i<6;i++)
                     s->block_last_index[i] = -1;
                 s->mv_dir = MV_DIR_FORWARD;
                 s->mv_type = MV_TYPE_16X16;
                 s->mv[0][0][0] = 0;
                 s->mv[0][0][1] = 0;
                 s->mb_skipped = 1;

                 *mb_type_ptr = MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;

                 return 0;
             }
         }
 
         if(s->msmpeg4_version==2)
             code = get_vlc2(&s->gb, v2_mb_type_vlc.table, V2_MB_TYPE_VLC_BITS, 1);
         else
             code = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
         if(code<0 || code>7){
             av_log(s->avctx, AV_LOG_ERROR, "cbpc %d invalid at %d %d\n", code, s->mb_x, s->mb_y);
             return -1;
         }
 
         s->mb_intra = code >>2;
 
         cbp = code & 0x3;
     } else {
         s->mb_intra = 1;
         if(s->msmpeg4_version==2)
             cbp= get_vlc2(&s->gb, v2_intra_cbpc_vlc.table, V2_INTRA_CBPC_VLC_BITS, 1);
         else
             cbp= get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 1);
         if(cbp<0 || cbp>3){
             av_log(s->avctx, AV_LOG_ERROR, "cbpc %d invalid at %d %d\n", cbp, s->mb_x, s->mb_y);
             return -1;
         }
     }
 
     if (!s->mb_intra) {
         int mx, my, cbpy;
 
         cbpy= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
         if(cbpy<0){
             av_log(s->avctx, AV_LOG_ERROR, "cbpy %d invalid at %d %d\n", cbp, s->mb_x, s->mb_y);
             return -1;
         }
 
         cbp|= cbpy<<2;
         if(s->msmpeg4_version==1 || (cbp&3) != 3) cbp^= 0x3C;
 
         ff_h263_pred_motion(s, 0, 0, &mx, &my);
         mx= msmpeg4v2_decode_motion(s, mx, 1);
         my= msmpeg4v2_decode_motion(s, my, 1);
 
         s->mv_dir = MV_DIR_FORWARD;
         s->mv_type = MV_TYPE_16X16;
         s->mv[0][0][0] = mx;
         s->mv[0][0][1] = my;

         *mb_type_ptr = MB_TYPE_L0 | MB_TYPE_16x16;

     } else {
         if(s->msmpeg4_version==2){
             s->ac_pred = get_bits1(&s->gb);
             cbp|= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1)<<2; //FIXME check errors
         } else{
             s->ac_pred = 0;
             cbp|= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1)<<2; //FIXME check errors
             if(s->pict_type==AV_PICTURE_TYPE_P) cbp^=0x3C;
         }

         *mb_type_ptr = MB_TYPE_INTRA;

     }
 

     s->bdsp.clear_blocks(s->block[0]);

     for (i = 0; i < 6; i++) {
         if (ff_msmpeg4_decode_block(s, block[i], i, (cbp >> (5 - i)) & 1, NULL) < 0)
         {
              av_log(s->avctx, AV_LOG_ERROR, "\nerror while decoding block: %d x %d (%d)\n", s->mb_x, s->mb_y, i);
              return -1;
         }
     }
     return 0;
 }
 
 static int msmpeg4v34_decode_mb(MpegEncContext *s, int16_t block[6][64])
 {
     int cbp, code, i;
     uint8_t *coded_val;
     uint32_t * const mb_type_ptr = &s->current_picture.mb_type[s->mb_x + s->mb_y*s->mb_stride];
 
     if (s->pict_type == AV_PICTURE_TYPE_P) {
         if (s->use_skip_mb_code) {
             if (get_bits1(&s->gb)) {
                 /* skip mb */
                 s->mb_intra = 0;
                 for(i=0;i<6;i++)
                     s->block_last_index[i] = -1;
                 s->mv_dir = MV_DIR_FORWARD;
                 s->mv_type = MV_TYPE_16X16;
                 s->mv[0][0][0] = 0;
                 s->mv[0][0][1] = 0;
                 s->mb_skipped = 1;
                 *mb_type_ptr = MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 
                 return 0;
             }
         }
 
         code = get_vlc2(&s->gb, ff_mb_non_intra_vlc[DEFAULT_INTER_INDEX].table, MB_NON_INTRA_VLC_BITS, 3);
         if (code < 0)
             return -1;
         //s->mb_intra = (code & 0x40) ? 0 : 1;
         s->mb_intra = (~code & 0x40) >> 6;
 
         cbp = code & 0x3f;
     } else {
         s->mb_intra = 1;
         code = get_vlc2(&s->gb, ff_msmp4_mb_i_vlc.table, MB_INTRA_VLC_BITS, 2);
         if (code < 0)
             return -1;
         /* predict coded block pattern */
         cbp = 0;
         for(i=0;i<6;i++) {
             int val = ((code >> (5 - i)) & 1);
             if (i < 4) {
                 int pred = ff_msmpeg4_coded_block_pred(s, i, &coded_val);
                 val = val ^ pred;
                 *coded_val = val;
             }
             cbp |= val << (5 - i);
         }
     }
 
     if (!s->mb_intra) {
         int mx, my;
         if(s->per_mb_rl_table && cbp){
             s->rl_table_index = decode012(&s->gb);
             s->rl_chroma_table_index = s->rl_table_index;
         }
         ff_h263_pred_motion(s, 0, 0, &mx, &my);
         if (ff_msmpeg4_decode_motion(s, &mx, &my) < 0)
             return -1;
         s->mv_dir = MV_DIR_FORWARD;
         s->mv_type = MV_TYPE_16X16;
         s->mv[0][0][0] = mx;
         s->mv[0][0][1] = my;
         *mb_type_ptr = MB_TYPE_L0 | MB_TYPE_16x16;
     } else {

         ff_dlog(s, "I at %d %d %d %06X\n", s->mb_x, s->mb_y,

                 ((cbp & 3) ? 1 : 0) +((cbp & 0x3C)? 2 : 0),
                 show_bits(&s->gb, 24));
         s->ac_pred = get_bits1(&s->gb);
         *mb_type_ptr = MB_TYPE_INTRA;
         if(s->inter_intra_pred){
             s->h263_aic_dir= get_vlc2(&s->gb, ff_inter_intra_vlc.table, INTER_INTRA_VLC_BITS, 1);

             ff_dlog(s, "%d%d %d %d/",

                     s->ac_pred, s->h263_aic_dir, s->mb_x, s->mb_y);
         }
         if(s->per_mb_rl_table && cbp){
             s->rl_table_index = decode012(&s->gb);
             s->rl_chroma_table_index = s->rl_table_index;
         }
     }
 

     s->bdsp.clear_blocks(s->block[0]);

     for (i = 0; i < 6; i++) {
         if (ff_msmpeg4_decode_block(s, block[i], i, (cbp >> (5 - i)) & 1, NULL) < 0)
         {
             av_log(s->avctx, AV_LOG_ERROR, "\nerror while decoding block: %d x %d (%d)\n", s->mb_x, s->mb_y, i);
             return -1;
         }
     }
 
     return 0;
 }
 
 /* init all vlc decoding tables */
 av_cold int ff_msmpeg4_decode_init(AVCodecContext *avctx)
 {
     MpegEncContext *s = avctx->priv_data;

     static volatile int done = 0;
     int i, ret;

     MVTable *mv;
 

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

     if (ff_h263_decode_init(avctx) < 0)
         return -1;
 
     ff_msmpeg4_common_init(s);
 
     if (!done) {
         for(i=0;i<NB_RL_TABLES;i++) {

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

         }
         INIT_VLC_RL(ff_rl_table[0], 642);
         INIT_VLC_RL(ff_rl_table[1], 1104);
         INIT_VLC_RL(ff_rl_table[2], 554);
         INIT_VLC_RL(ff_rl_table[3], 940);
         INIT_VLC_RL(ff_rl_table[4], 962);
         INIT_VLC_RL(ff_rl_table[5], 554);
 
         mv = &ff_mv_tables[0];
         INIT_VLC_STATIC(&mv->vlc, MV_VLC_BITS, mv->n + 1,
                     mv->table_mv_bits, 1, 1,
                     mv->table_mv_code, 2, 2, 3714);
         mv = &ff_mv_tables[1];
         INIT_VLC_STATIC(&mv->vlc, MV_VLC_BITS, mv->n + 1,
                     mv->table_mv_bits, 1, 1,
                     mv->table_mv_code, 2, 2, 2694);
 
         INIT_VLC_STATIC(&ff_msmp4_dc_luma_vlc[0], DC_VLC_BITS, 120,
                  &ff_table0_dc_lum[0][1], 8, 4,
                  &ff_table0_dc_lum[0][0], 8, 4, 1158);
         INIT_VLC_STATIC(&ff_msmp4_dc_chroma_vlc[0], DC_VLC_BITS, 120,
                  &ff_table0_dc_chroma[0][1], 8, 4,
                  &ff_table0_dc_chroma[0][0], 8, 4, 1118);
         INIT_VLC_STATIC(&ff_msmp4_dc_luma_vlc[1], DC_VLC_BITS, 120,
                  &ff_table1_dc_lum[0][1], 8, 4,
                  &ff_table1_dc_lum[0][0], 8, 4, 1476);
         INIT_VLC_STATIC(&ff_msmp4_dc_chroma_vlc[1], DC_VLC_BITS, 120,
                  &ff_table1_dc_chroma[0][1], 8, 4,
                  &ff_table1_dc_chroma[0][0], 8, 4, 1216);
 
         INIT_VLC_STATIC(&v2_dc_lum_vlc, DC_VLC_BITS, 512,
                  &ff_v2_dc_lum_table[0][1], 8, 4,
                  &ff_v2_dc_lum_table[0][0], 8, 4, 1472);
         INIT_VLC_STATIC(&v2_dc_chroma_vlc, DC_VLC_BITS, 512,
                  &ff_v2_dc_chroma_table[0][1], 8, 4,
                  &ff_v2_dc_chroma_table[0][0], 8, 4, 1506);
 
         INIT_VLC_STATIC(&v2_intra_cbpc_vlc, V2_INTRA_CBPC_VLC_BITS, 4,
                  &ff_v2_intra_cbpc[0][1], 2, 1,
                  &ff_v2_intra_cbpc[0][0], 2, 1, 8);
         INIT_VLC_STATIC(&v2_mb_type_vlc, V2_MB_TYPE_VLC_BITS, 8,
                  &ff_v2_mb_type[0][1], 2, 1,
                  &ff_v2_mb_type[0][0], 2, 1, 128);
         INIT_VLC_STATIC(&v2_mv_vlc, V2_MV_VLC_BITS, 33,
                  &ff_mvtab[0][1], 2, 1,
                  &ff_mvtab[0][0], 2, 1, 538);
 
         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[0], MB_NON_INTRA_VLC_BITS, 128,
                      &ff_wmv2_inter_table[0][0][1], 8, 4,
                      &ff_wmv2_inter_table[0][0][0], 8, 4, 1636);
         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[1], MB_NON_INTRA_VLC_BITS, 128,
                      &ff_wmv2_inter_table[1][0][1], 8, 4,
                      &ff_wmv2_inter_table[1][0][0], 8, 4, 2648);
         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[2], MB_NON_INTRA_VLC_BITS, 128,
                      &ff_wmv2_inter_table[2][0][1], 8, 4,
                      &ff_wmv2_inter_table[2][0][0], 8, 4, 1532);
         INIT_VLC_STATIC(&ff_mb_non_intra_vlc[3], MB_NON_INTRA_VLC_BITS, 128,
                      &ff_wmv2_inter_table[3][0][1], 8, 4,
                      &ff_wmv2_inter_table[3][0][0], 8, 4, 2488);
 
         INIT_VLC_STATIC(&ff_msmp4_mb_i_vlc, MB_INTRA_VLC_BITS, 64,
                  &ff_msmp4_mb_i_table[0][1], 4, 2,
                  &ff_msmp4_mb_i_table[0][0], 4, 2, 536);
 
         INIT_VLC_STATIC(&ff_inter_intra_vlc, INTER_INTRA_VLC_BITS, 4,
                  &ff_table_inter_intra[0][1], 2, 1,
                  &ff_table_inter_intra[0][0], 2, 1, 8);

         done = 1;

     }
 
     switch(s->msmpeg4_version){
     case 1:
     case 2:
         s->decode_mb= msmpeg4v12_decode_mb;
         break;
     case 3:
     case 4:
         s->decode_mb= msmpeg4v34_decode_mb;
         break;
     case 5:
         if (CONFIG_WMV2_DECODER)
             s->decode_mb= ff_wmv2_decode_mb;
     case 6:
         //FIXME + TODO VC1 decode mb
         break;
     }
 
     s->slice_height= s->mb_height; //to avoid 1/0 if the first frame is not a keyframe
 
     return 0;
 }
 
 int ff_msmpeg4_decode_picture_header(MpegEncContext * s)
 {
     int code;
 
     if(s->msmpeg4_version==1){
         int start_code = get_bits_long(&s->gb, 32);
         if(start_code!=0x00000100){
             av_log(s->avctx, AV_LOG_ERROR, "invalid startcode\n");
             return -1;
         }
 
         skip_bits(&s->gb, 5); // frame number */
     }
 
     s->pict_type = get_bits(&s->gb, 2) + 1;
     if (s->pict_type != AV_PICTURE_TYPE_I &&
         s->pict_type != AV_PICTURE_TYPE_P){
         av_log(s->avctx, AV_LOG_ERROR, "invalid picture type\n");
         return -1;
     }
 #if 0
 {
     static int had_i=0;
     if(s->pict_type == AV_PICTURE_TYPE_I) had_i=1;
     if(!had_i) return -1;
 }
 #endif
     s->chroma_qscale= s->qscale = get_bits(&s->gb, 5);
     if(s->qscale==0){
         av_log(s->avctx, AV_LOG_ERROR, "invalid qscale\n");
         return -1;
     }
 
     if (s->pict_type == AV_PICTURE_TYPE_I) {
         code = get_bits(&s->gb, 5);
         if(s->msmpeg4_version==1){
             if(code==0 || code>s->mb_height){
                 av_log(s->avctx, AV_LOG_ERROR, "invalid slice height %d\n", code);
                 return -1;
             }
 
             s->slice_height = code;
         }else{
             /* 0x17: one slice, 0x18: two slices, ... */
             if (code < 0x17){
                 av_log(s->avctx, AV_LOG_ERROR, "error, slice code was %X\n", code);
                 return -1;
             }
 
             s->slice_height = s->mb_height / (code - 0x16);
         }
 
         switch(s->msmpeg4_version){
         case 1:
         case 2:
             s->rl_chroma_table_index = 2;
             s->rl_table_index = 2;
 
             s->dc_table_index = 0; //not used
             break;
         case 3:
             s->rl_chroma_table_index = decode012(&s->gb);
             s->rl_table_index = decode012(&s->gb);
 
             s->dc_table_index = get_bits1(&s->gb);
             break;
         case 4:
             ff_msmpeg4_decode_ext_header(s, (2+5+5+17+7)/8);
 
             if(s->bit_rate > MBAC_BITRATE) s->per_mb_rl_table= get_bits1(&s->gb);
             else                           s->per_mb_rl_table= 0;
 
             if(!s->per_mb_rl_table){
                 s->rl_chroma_table_index = decode012(&s->gb);
                 s->rl_table_index = decode012(&s->gb);
             }
 
             s->dc_table_index = get_bits1(&s->gb);
             s->inter_intra_pred= 0;
             break;
         }
         s->no_rounding = 1;
         if(s->avctx->debug&FF_DEBUG_PICT_INFO)
             av_log(s->avctx, AV_LOG_DEBUG, "qscale:%d rlc:%d rl:%d dc:%d mbrl:%d slice:%d   \n",
                 s->qscale,
                 s->rl_chroma_table_index,
                 s->rl_table_index,
                 s->dc_table_index,
                 s->per_mb_rl_table,
                 s->slice_height);
     } else {
         switch(s->msmpeg4_version){
         case 1:
         case 2:
             if(s->msmpeg4_version==1)
                 s->use_skip_mb_code = 1;
             else
                 s->use_skip_mb_code = get_bits1(&s->gb);
             s->rl_table_index = 2;
             s->rl_chroma_table_index = s->rl_table_index;
             s->dc_table_index = 0; //not used
             s->mv_table_index = 0;
             break;
         case 3:
             s->use_skip_mb_code = get_bits1(&s->gb);
             s->rl_table_index = decode012(&s->gb);
             s->rl_chroma_table_index = s->rl_table_index;
 
             s->dc_table_index = get_bits1(&s->gb);
 
             s->mv_table_index = get_bits1(&s->gb);
             break;
         case 4:
             s->use_skip_mb_code = get_bits1(&s->gb);
 
             if(s->bit_rate > MBAC_BITRATE) s->per_mb_rl_table= get_bits1(&s->gb);
             else                           s->per_mb_rl_table= 0;
 
             if(!s->per_mb_rl_table){
                 s->rl_table_index = decode012(&s->gb);
                 s->rl_chroma_table_index = s->rl_table_index;
             }
 
             s->dc_table_index = get_bits1(&s->gb);
 
             s->mv_table_index = get_bits1(&s->gb);
             s->inter_intra_pred= (s->width*s->height < 320*240 && s->bit_rate<=II_BITRATE);
             break;
         }
 
         if(s->avctx->debug&FF_DEBUG_PICT_INFO)
             av_log(s->avctx, AV_LOG_DEBUG, "skip:%d rl:%d rlc:%d dc:%d mv:%d mbrl:%d qp:%d   \n",
                 s->use_skip_mb_code,
                 s->rl_table_index,
                 s->rl_chroma_table_index,
                 s->dc_table_index,
                 s->mv_table_index,
                 s->per_mb_rl_table,
                 s->qscale);
 
         if(s->flipflop_rounding){
             s->no_rounding ^= 1;
         }else{
             s->no_rounding = 0;
         }
     }

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

             s->inter_intra_pred, s->width, s->height);
 
     s->esc3_level_length= 0;
     s->esc3_run_length= 0;
 
     return 0;
 }
 
 int ff_msmpeg4_decode_ext_header(MpegEncContext * s, int buf_size)
 {
     int left= buf_size*8 - get_bits_count(&s->gb);
     int length= s->msmpeg4_version>=3 ? 17 : 16;
     /* the alt_bitstream reader could read over the end so we need to check it */
     if(left>=length && left<length+8)
     {
         skip_bits(&s->gb, 5); /* fps */
         s->bit_rate= get_bits(&s->gb, 11)*1024;
         if(s->msmpeg4_version>=3)
             s->flipflop_rounding= get_bits1(&s->gb);
         else
             s->flipflop_rounding= 0;
     }
     else if(left<length+8)
     {
         s->flipflop_rounding= 0;
         if(s->msmpeg4_version != 2)
             av_log(s->avctx, AV_LOG_ERROR, "ext header missing, %d left\n", left);
     }
     else
     {
         av_log(s->avctx, AV_LOG_ERROR, "I frame too long, ignoring ext header\n");
     }
 
     return 0;
 }
 
 static int msmpeg4_decode_dc(MpegEncContext * s, int n, int *dir_ptr)
 {
     int level, pred;
 
     if(s->msmpeg4_version<=2){
         if (n < 4) {
             level = get_vlc2(&s->gb, v2_dc_lum_vlc.table, DC_VLC_BITS, 3);
         } else {
             level = get_vlc2(&s->gb, v2_dc_chroma_vlc.table, DC_VLC_BITS, 3);
         }

         if (level < 0) {
             av_log(s->avctx, AV_LOG_ERROR, "illegal dc vlc\n");

             *dir_ptr = 0;

             return -1;

         }

         level-=256;
     }else{  //FIXME optimize use unified tables & index
         if (n < 4) {
             level = get_vlc2(&s->gb, ff_msmp4_dc_luma_vlc[s->dc_table_index].table, DC_VLC_BITS, 3);
         } else {
             level = get_vlc2(&s->gb, ff_msmp4_dc_chroma_vlc[s->dc_table_index].table, DC_VLC_BITS, 3);
         }
         if (level < 0){
             av_log(s->avctx, AV_LOG_ERROR, "illegal dc vlc\n");

             *dir_ptr = 0;

             return -1;
         }
 
         if (level == DC_MAX) {
             level = get_bits(&s->gb, 8);
             if (get_bits1(&s->gb))
                 level = -level;
         } else if (level != 0) {
             if (get_bits1(&s->gb))
                 level = -level;
         }
     }
 
     if(s->msmpeg4_version==1){
         int32_t *dc_val;
         pred = msmpeg4v1_pred_dc(s, n, &dc_val);
         level += pred;
 
         /* update predictor */
         *dc_val= level;
     }else{
         int16_t *dc_val;
         pred   = ff_msmpeg4_pred_dc(s, n, &dc_val, dir_ptr);
         level += pred;
 
         /* update predictor */
         if (n < 4) {
             *dc_val = level * s->y_dc_scale;
         } else {
             *dc_val = level * s->c_dc_scale;
         }
     }
 
     return level;
 }
 
 //#define ERROR_DETAILS
 int ff_msmpeg4_decode_block(MpegEncContext * s, int16_t * block,
                               int n, int coded, const uint8_t *scan_table)
 {
     int level, i, last, run, run_diff;
     int av_uninit(dc_pred_dir);
     RLTable *rl;
     RL_VLC_ELEM *rl_vlc;
     int qmul, qadd;
 
     if (s->mb_intra) {
         qmul=1;
         qadd=0;
 
         /* DC coef */
         level = msmpeg4_decode_dc(s, n, &dc_pred_dir);
 
         if (level < 0){
             av_log(s->avctx, AV_LOG_ERROR, "dc overflow- block: %d qscale: %d//\n", n, s->qscale);
             if(s->inter_intra_pred) level=0;
         }
         if (n < 4) {
             rl = &ff_rl_table[s->rl_table_index];
             if(level > 256*s->y_dc_scale){
                 av_log(s->avctx, AV_LOG_ERROR, "dc overflow+ L qscale: %d//\n", s->qscale);
                 if(!s->inter_intra_pred) return -1;
             }
         } else {
             rl = &ff_rl_table[3 + s->rl_chroma_table_index];
             if(level > 256*s->c_dc_scale){
                 av_log(s->avctx, AV_LOG_ERROR, "dc overflow+ C qscale: %d//\n", s->qscale);
                 if(!s->inter_intra_pred) return -1;
             }
         }
         block[0] = level;
 
         run_diff = s->msmpeg4_version >= 4;
         i = 0;
         if (!coded) {
             goto not_coded;
         }
         if (s->ac_pred) {
             if (dc_pred_dir == 0)
                 scan_table = s->intra_v_scantable.permutated; /* left */
             else
                 scan_table = s->intra_h_scantable.permutated; /* top */
         } else {
             scan_table = s->intra_scantable.permutated;
         }
         rl_vlc= rl->rl_vlc[0];
     } else {
         qmul = s->qscale << 1;
         qadd = (s->qscale - 1) | 1;
         i = -1;
         rl = &ff_rl_table[3 + s->rl_table_index];
 
         if(s->msmpeg4_version==2)
             run_diff = 0;
         else
             run_diff = 1;
 
         if (!coded) {
             s->block_last_index[n] = i;
             return 0;
         }
         if(!scan_table)
             scan_table = s->inter_scantable.permutated;
         rl_vlc= rl->rl_vlc[s->qscale];
     }
   {
     OPEN_READER(re, &s->gb);
     for(;;) {
         UPDATE_CACHE(re, &s->gb);
         GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 0);
         if (level==0) {
             int cache;
             cache= GET_CACHE(re, &s->gb);
             /* escape */
             if (s->msmpeg4_version==1 || (cache&0x80000000)==0) {
                 if (s->msmpeg4_version==1 || (cache&0x40000000)==0) {
                     /* third escape */
                     if(s->msmpeg4_version!=1) LAST_SKIP_BITS(re, &s->gb, 2);
                     UPDATE_CACHE(re, &s->gb);
                     if(s->msmpeg4_version<=3){
                         last=  SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
                         run=   SHOW_UBITS(re, &s->gb, 6); SKIP_CACHE(re, &s->gb, 6);
                         level= SHOW_SBITS(re, &s->gb, 8);
                         SKIP_COUNTER(re, &s->gb, 1+6+8);
                     }else{
                         int sign;
                         last=  SHOW_UBITS(re, &s->gb, 1); SKIP_BITS(re, &s->gb, 1);
                         if(!s->esc3_level_length){
                             int ll;

                             ff_dlog(s->avctx, "ESC-3 %X at %d %d\n",

                                     show_bits(&s->gb, 24), s->mb_x, s->mb_y);
                             if(s->qscale<8){
                                 ll= SHOW_UBITS(re, &s->gb, 3); SKIP_BITS(re, &s->gb, 3);
                                 if(ll==0){
                                     ll= 8+SHOW_UBITS(re, &s->gb, 1); SKIP_BITS(re, &s->gb, 1);
                                 }
                             }else{
                                 ll=2;
                                 while(ll<8 && SHOW_UBITS(re, &s->gb, 1)==0){
                                     ll++;
                                     SKIP_BITS(re, &s->gb, 1);
                                 }
                                 if(ll<8) SKIP_BITS(re, &s->gb, 1);
                             }
 
                             s->esc3_level_length= ll;
                             s->esc3_run_length= SHOW_UBITS(re, &s->gb, 2) + 3; SKIP_BITS(re, &s->gb, 2);
                             UPDATE_CACHE(re, &s->gb);
                         }
                         run=   SHOW_UBITS(re, &s->gb, s->esc3_run_length);
                         SKIP_BITS(re, &s->gb, s->esc3_run_length);
 
                         sign=  SHOW_UBITS(re, &s->gb, 1);
                         SKIP_BITS(re, &s->gb, 1);
 
                         level= SHOW_UBITS(re, &s->gb, s->esc3_level_length);
                         SKIP_BITS(re, &s->gb, s->esc3_level_length);
                         if(sign) level= -level;
                     }
 
 #if 0 // waste of time / this will detect very few errors
                     {
                         const int abs_level= FFABS(level);
                         const int run1= run - rl->max_run[last][abs_level] - run_diff;
                         if(abs_level<=MAX_LEVEL && run<=MAX_RUN){
                             if(abs_level <= rl->max_level[last][run]){
                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, vlc encoding possible\n");
                                 return DECODING_AC_LOST;
                             }
                             if(abs_level <= rl->max_level[last][run]*2){
                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 1 encoding possible\n");
                                 return DECODING_AC_LOST;
                             }
                             if(run1>=0 && abs_level <= rl->max_level[last][run1]){
                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 2 encoding possible\n");
                                 return DECODING_AC_LOST;
                             }
                         }
                     }
 #endif
                     //level = level * qmul + (level>0) * qadd - (level<=0) * qadd ;
                     if (level>0) level= level * qmul + qadd;
                     else         level= level * qmul - qadd;
 #if 0 // waste of time too :(
                     if(level>2048 || level<-2048){
                         av_log(s->avctx, AV_LOG_ERROR, "|level| overflow in 3. esc\n");
                         return DECODING_AC_LOST;
                     }
 #endif
                     i+= run + 1;
                     if(last) i+=192;
 #ifdef ERROR_DETAILS
                 if(run==66)
                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code in ESC3 level=%d\n", level);
                 else if((i>62 && i<192) || i>192+63)
                     av_log(s->avctx, AV_LOG_ERROR, "run overflow in ESC3 i=%d run=%d level=%d\n", i, run, level);
 #endif
                 } else {
                     /* second escape */
                     SKIP_BITS(re, &s->gb, 2);
                     GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
                     i+= run + rl->max_run[run>>7][level/qmul] + run_diff; //FIXME opt indexing
                     level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
                     LAST_SKIP_BITS(re, &s->gb, 1);
 #ifdef ERROR_DETAILS
                 if(run==66)
                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code in ESC2 level=%d\n", level);
                 else if((i>62 && i<192) || i>192+63)
                     av_log(s->avctx, AV_LOG_ERROR, "run overflow in ESC2 i=%d run=%d level=%d\n", i, run, level);
 #endif
                 }
             } else {
                 /* first escape */
                 SKIP_BITS(re, &s->gb, 1);
                 GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
                 i+= run;
                 level = level + rl->max_level[run>>7][(run-1)&63] * qmul;//FIXME opt indexing
                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
                 LAST_SKIP_BITS(re, &s->gb, 1);
 #ifdef ERROR_DETAILS
                 if(run==66)
                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code in ESC1 level=%d\n", level);
                 else if((i>62 && i<192) || i>192+63)
                     av_log(s->avctx, AV_LOG_ERROR, "run overflow in ESC1 i=%d run=%d level=%d\n", i, run, level);
 #endif
             }
         } else {
             i+= run;
             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
             LAST_SKIP_BITS(re, &s->gb, 1);
 #ifdef ERROR_DETAILS
                 if(run==66)
                     av_log(s->avctx, AV_LOG_ERROR, "illegal vlc code level=%d\n", level);
                 else if((i>62 && i<192) || i>192+63)
                     av_log(s->avctx, AV_LOG_ERROR, "run overflow i=%d run=%d level=%d\n", i, run, level);
 #endif
         }
         if (i > 62){
             i-= 192;
             if(i&(~63)){
                 const int left= get_bits_left(&s->gb);

                 if (((i + 192 == 64 && level / qmul == -1) ||

                      !(s->avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT))) &&

                     left >= 0) {

                     av_log(s->avctx, AV_LOG_ERROR, "ignoring overflow at %d %d\n", s->mb_x, s->mb_y);

                     i = 63;

                     break;
                 }else{
                     av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
                     return -1;
                 }
             }
 
             block[scan_table[i]] = level;
             break;
         }
 
         block[scan_table[i]] = level;
     }
     CLOSE_READER(re, &s->gb);
   }
  not_coded:
     if (s->mb_intra) {
         ff_mpeg4_pred_ac(s, block, n, dc_pred_dir);
         if (s->ac_pred) {
             i = 63; /* XXX: not optimal */
         }
     }
     if(s->msmpeg4_version>=4 && i>0) i=63; //FIXME/XXX optimize
     s->block_last_index[n] = i;
 
     return 0;
 }
 
 int ff_msmpeg4_decode_motion(MpegEncContext * s,
                                  int *mx_ptr, int *my_ptr)
 {
     MVTable *mv;
     int code, mx, my;
 
     mv = &ff_mv_tables[s->mv_table_index];
 
     code = get_vlc2(&s->gb, mv->vlc.table, MV_VLC_BITS, 2);
     if (code < 0){
         av_log(s->avctx, AV_LOG_ERROR, "illegal MV code at %d %d\n", s->mb_x, s->mb_y);
         return -1;
     }
     if (code == mv->n) {
         mx = get_bits(&s->gb, 6);
         my = get_bits(&s->gb, 6);
     } else {
         mx = mv->table_mvx[code];
         my = mv->table_mvy[code];
     }
 
     mx += *mx_ptr - 32;
     my += *my_ptr - 32;
     /* WARNING : they do not do exactly modulo encoding */
     if (mx <= -64)
         mx += 64;
     else if (mx >= 64)
         mx -= 64;
 
     if (my <= -64)
         my += 64;
     else if (my >= 64)
         my -= 64;
     *mx_ptr = mx;
     *my_ptr = my;
     return 0;
 }
 
 AVCodec ff_msmpeg4v1_decoder = {
     .name           = "msmpeg4v1",

     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 Microsoft variant version 1"),

     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_MSMPEG4V1,
     .priv_data_size = sizeof(MpegEncContext),
     .init           = ff_msmpeg4_decode_init,
     .close          = ff_h263_decode_end,
     .decode         = ff_h263_decode_frame,

     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,

     .max_lowres     = 3,

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

 };
 
 AVCodec ff_msmpeg4v2_decoder = {
     .name           = "msmpeg4v2",

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

     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_MSMPEG4V2,
     .priv_data_size = sizeof(MpegEncContext),
     .init           = ff_msmpeg4_decode_init,
     .close          = ff_h263_decode_end,
     .decode         = ff_h263_decode_frame,

     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,

     .max_lowres     = 3,

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

 };
 
 AVCodec ff_msmpeg4v3_decoder = {
     .name           = "msmpeg4",

     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 Microsoft variant version 3"),

     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_MSMPEG4V3,
     .priv_data_size = sizeof(MpegEncContext),
     .init           = ff_msmpeg4_decode_init,
     .close          = ff_h263_decode_end,
     .decode         = ff_h263_decode_frame,

     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,

     .max_lowres     = 3,

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

 };
 
 AVCodec ff_wmv1_decoder = {
     .name           = "wmv1",

     .long_name      = NULL_IF_CONFIG_SMALL("Windows Media Video 7"),

     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_WMV1,
     .priv_data_size = sizeof(MpegEncContext),
     .init           = ff_msmpeg4_decode_init,
     .close          = ff_h263_decode_end,
     .decode         = ff_h263_decode_frame,

     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1,

     .max_lowres     = 3,

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

 };