/*

  * VC-1 and WMV3 decoder common code

  * Copyright (c) 2011 Mashiat Sarker Shakkhar

  * Copyright (c) 2006-2007 Konstantin Shishkov

  * Partly based on vc9.c (c) 2005 Anonymous, Alex Beregszaszi, Michael Niedermayer

  *

  * 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

  * VC-1 and WMV3 decoder common code

  *
  */

 #include "internal.h"

 #include "dsputil.h"
 #include "avcodec.h"
 #include "mpegvideo.h"

 #include "vc1.h"

 #include "vc1data.h"

 #include "msmpeg4data.h"

 #include "unary.h"

 #include "simple_idct.h"

 #undef NDEBUG
 #include <assert.h>
 

 /***********************************************************************/
 /**

  * @name VC-1 Bitplane decoding

  * @see 8.7, p56
  * @{
  */
 

 /**

  * Imode types
  * @{
  */

 enum Imode {
     IMODE_RAW,
     IMODE_NORM2,
     IMODE_DIFF2,
     IMODE_NORM6,
     IMODE_DIFF6,
     IMODE_ROWSKIP,
     IMODE_COLSKIP
 };

 /** @} */ //imode defines
 

 /** Decode rows by checking if they are skipped

  * @param plane Buffer to store decoded bits
  * @param[in] width Width of this buffer
  * @param[in] height Height of this buffer
  * @param[in] stride of this buffer
  */

 static void decode_rowskip(uint8_t* plane, int width, int height, int stride,
                            GetBitContext *gb)
 {

     int x, y;
 

     for (y = 0; y < height; y++) {

         if (!get_bits1(gb)) //rowskip

             memset(plane, 0, width);
         else

             for (x = 0; x < width; x++)

                 plane[x] = get_bits1(gb);

         plane += stride;
     }
 }
 

 /** Decode columns by checking if they are skipped

  * @param plane Buffer to store decoded bits
  * @param[in] width Width of this buffer
  * @param[in] height Height of this buffer
  * @param[in] stride of this buffer

  * @todo FIXME: Optimize

  */

 static void decode_colskip(uint8_t* plane, int width, int height, int stride,
                            GetBitContext *gb)
 {

     int x, y;
 

     for (x = 0; x < width; x++) {

         if (!get_bits1(gb)) //colskip

             for (y = 0; y < height; y++)

                 plane[y*stride] = 0;
         else

             for (y = 0; y < height; y++)

                 plane[y*stride] = get_bits1(gb);

         plane ++;
     }
 }
 

 /** Decode a bitplane's bits

  * @param data bitplane where to store the decode bits
  * @param[out] raw_flag pointer to the flag indicating that this bitplane is not coded explicitly

  * @param v VC-1 context for bit reading and logging

  * @return Status

  * @todo FIXME: Optimize

  */

 static int bitplane_decoding(uint8_t* data, int *raw_flag, VC1Context *v)

 {

     GetBitContext *gb = &v->s.gb;
 

     int imode, x, y, code, offset;

     uint8_t invert, *planep = data;
     int width, height, stride;

     width  = v->s.mb_width;

     height = v->s.mb_height >> v->field_mode;

     stride = v->s.mb_stride;

     invert = get_bits1(gb);

     imode = get_vlc2(gb, ff_vc1_imode_vlc.table, VC1_IMODE_VLC_BITS, 1);

     *raw_flag = 0;

     switch (imode) {

     case IMODE_RAW:

         //Data is actually read in the MB layer (same for all tests == "raw")

         *raw_flag = 1; //invert ignored

         return invert;

     case IMODE_DIFF2:
     case IMODE_NORM2:

         if ((height * width) & 1) {

             *planep++ = get_bits1(gb);

             offset    = 1;

         }

         else
             offset = 0;

         // decode bitplane as one long line

         for (y = offset; y < height * width; y += 2) {

             code = get_vlc2(gb, ff_vc1_norm2_vlc.table, VC1_NORM2_VLC_BITS, 1);

             *planep++ = code & 1;
             offset++;

             if (offset == width) {
                 offset  = 0;

                 planep += stride - width;

             }

             *planep++ = code >> 1;
             offset++;

             if (offset == width) {
                 offset  = 0;

                 planep += stride - width;

             }

         }

         break;
     case IMODE_DIFF6:
     case IMODE_NORM6:

         if (!(height % 3) && (width % 3)) { // use 2x3 decoding
             for (y = 0; y < height; y += 3) {
                 for (x = width & 1; x < width; x += 2) {

                     code = get_vlc2(gb, ff_vc1_norm6_vlc.table, VC1_NORM6_VLC_BITS, 2);

                     if (code < 0) {

                         av_log(v->s.avctx, AV_LOG_DEBUG, "invalid NORM-6 VLC\n");
                         return -1;
                     }

                     planep[x + 0]              = (code >> 0) & 1;
                     planep[x + 1]              = (code >> 1) & 1;
                     planep[x + 0 + stride]     = (code >> 2) & 1;
                     planep[x + 1 + stride]     = (code >> 3) & 1;

                     planep[x + 0 + stride * 2] = (code >> 4) & 1;
                     planep[x + 1 + stride * 2] = (code >> 5) & 1;

                 }

                 planep += stride * 3;

             }

             if (width & 1)
                 decode_colskip(data, 1, height, stride, &v->s.gb);

         } else { // 3x2

             planep += (height & 1) * stride;

             for (y = height & 1; y < height; y += 2) {
                 for (x = width % 3; x < width; x += 3) {

                     code = get_vlc2(gb, ff_vc1_norm6_vlc.table, VC1_NORM6_VLC_BITS, 2);

                     if (code < 0) {

                         av_log(v->s.avctx, AV_LOG_DEBUG, "invalid NORM-6 VLC\n");
                         return -1;
                     }

                     planep[x + 0]          = (code >> 0) & 1;
                     planep[x + 1]          = (code >> 1) & 1;
                     planep[x + 2]          = (code >> 2) & 1;

                     planep[x + 0 + stride] = (code >> 3) & 1;
                     planep[x + 1 + stride] = (code >> 4) & 1;
                     planep[x + 2 + stride] = (code >> 5) & 1;

                 }

                 planep += stride * 2;

             }

             x = width % 3;

             if (x)
                 decode_colskip(data,             x, height, stride, &v->s.gb);
             if (height & 1)
                 decode_rowskip(data + x, width - x,      1, stride, &v->s.gb);

         }

         break;
     case IMODE_ROWSKIP:

         decode_rowskip(data, width, height, stride, &v->s.gb);

         break;

     case IMODE_COLSKIP:

         decode_colskip(data, width, height, stride, &v->s.gb);

         break;

     default:
         break;

     }
 
     /* Applying diff operator */

     if (imode == IMODE_DIFF2 || imode == IMODE_DIFF6) {

         planep = data;

         planep[0] ^= invert;

         for (x = 1; x < width; x++)

             planep[x] ^= planep[x-1];

         for (y = 1; y < height; y++) {

             planep += stride;
             planep[0] ^= planep[-stride];

             for (x = 1; x < width; x++) {

                 if (planep[x-1] != planep[x-stride]) planep[x] ^= invert;
                 else                                 planep[x] ^= planep[x-1];

             }
         }

     } else if (invert) {

         planep = data;

         for (x = 0; x < stride * height; x++)
             planep[x] = !planep[x]; //FIXME stride

     }

     return (imode << 1) + invert;

 }

 /** @} */ //Bitplane group

 /***********************************************************************/
 /** VOP Dquant decoding

  * @param v VC-1 Context

  */

 static int vop_dquant_decoding(VC1Context *v)

 {

     GetBitContext *gb = &v->s.gb;

     int pqdiff;
 
     //variable size

     if (v->dquant == 2) {

         pqdiff = get_bits(gb, 3);

         if (pqdiff == 7)
             v->altpq = get_bits(gb, 5);
         else
             v->altpq = v->pq + pqdiff + 1;
     } else {

         v->dquantfrm = get_bits1(gb);

         if (v->dquantfrm) {

             v->dqprofile = get_bits(gb, 2);

             switch (v->dqprofile) {

             case DQPROFILE_SINGLE_EDGE:
             case DQPROFILE_DOUBLE_EDGES:

                 v->dqsbedge = get_bits(gb, 2);

                 break;
             case DQPROFILE_ALL_MBS:

                 v->dqbilevel = get_bits1(gb);

                 if (!v->dqbilevel)

                     v->halfpq = 0;

             default:
                 break; //Forbidden ?

             }

             if (v->dqbilevel || v->dqprofile != DQPROFILE_ALL_MBS) {

                 pqdiff = get_bits(gb, 3);

                 if (pqdiff == 7)
                     v->altpq = get_bits(gb, 5);
                 else
                     v->altpq = v->pq + pqdiff + 1;

             }
         }
     }
     return 0;
 }
 

 static int decode_sequence_header_adv(VC1Context *v, GetBitContext *gb);
 

 /**
  * Decode Simple/Main Profiles sequence header
  * @see Figure 7-8, p16-17
  * @param avctx Codec context
  * @param gb GetBit context initialized from Codec context extra_data

  * @return Status
  */

 int vc1_decode_sequence_header(AVCodecContext *avctx, VC1Context *v, GetBitContext *gb)

 {

     av_log(avctx, AV_LOG_DEBUG, "Header: %0X\n", show_bits(gb, 32));

     v->profile = get_bits(gb, 2);

     if (v->profile == PROFILE_COMPLEX) {

         av_log(avctx, AV_LOG_WARNING, "WMV3 Complex Profile is not fully supported\n");

     }

     if (v->profile == PROFILE_ADVANCED) {

         v->zz_8x4 = ff_vc1_adv_progressive_8x4_zz;
         v->zz_4x8 = ff_vc1_adv_progressive_4x8_zz;

         return decode_sequence_header_adv(v, gb);

     } else {

         v->zz_8x4 = wmv2_scantableA;
         v->zz_4x8 = wmv2_scantableB;

         v->res_y411   = get_bits1(gb);
         v->res_sprite = get_bits1(gb);

         if (v->res_y411) {

             av_log(avctx, AV_LOG_ERROR,

                    "Old interlaced mode is not supported\n");
             return -1;
         }

     }
 

     // (fps-2)/4 (->30)
     v->frmrtq_postproc = get_bits(gb, 3); //common
     // (bitrate-32kbps)/64kbps
     v->bitrtq_postproc = get_bits(gb, 5); //common

     v->s.loop_filter   = get_bits1(gb); //common
     if (v->s.loop_filter == 1 && v->profile == PROFILE_SIMPLE) {

         av_log(avctx, AV_LOG_ERROR,

                "LOOPFILTER shall not be enabled in Simple Profile\n");

     }

     if (v->s.avctx->skip_loop_filter >= AVDISCARD_ALL)

         v->s.loop_filter = 0;

     v->res_x8          = get_bits1(gb); //reserved
     v->multires        = get_bits1(gb);
     v->res_fasttx      = get_bits1(gb);
     if (!v->res_fasttx) {
         v->vc1dsp.vc1_inv_trans_8x8    = ff_simple_idct_8;
         v->vc1dsp.vc1_inv_trans_8x4    = ff_simple_idct84_add;
         v->vc1dsp.vc1_inv_trans_4x8    = ff_simple_idct48_add;
         v->vc1dsp.vc1_inv_trans_4x4    = ff_simple_idct44_add;

         v->vc1dsp.vc1_inv_trans_8x8_dc = ff_simple_idct_add_8;

         v->vc1dsp.vc1_inv_trans_8x4_dc = ff_simple_idct84_add;
         v->vc1dsp.vc1_inv_trans_4x8_dc = ff_simple_idct48_add;
         v->vc1dsp.vc1_inv_trans_4x4_dc = ff_simple_idct44_add;

     }
 

     v->fastuvmc        = get_bits1(gb); //common
     if (!v->profile && !v->fastuvmc) {

         av_log(avctx, AV_LOG_ERROR,
                "FASTUVMC unavailable in Simple Profile\n");
         return -1;

     }

     v->extended_mv     = get_bits1(gb); //common

     if (!v->profile && v->extended_mv)
     {
         av_log(avctx, AV_LOG_ERROR,
                "Extended MVs unavailable in Simple Profile\n");
         return -1;
     }

     v->dquant          = get_bits(gb, 2); //common
     v->vstransform     = get_bits1(gb); //common

     v->res_transtab    = get_bits1(gb);

     if (v->res_transtab)

     {

         av_log(avctx, AV_LOG_ERROR,
                "1 for reserved RES_TRANSTAB is forbidden\n");
         return -1;

     }

     v->overlap         = get_bits1(gb); //common

     v->s.resync_marker = get_bits1(gb);

     v->rangered        = get_bits1(gb);
     if (v->rangered && v->profile == PROFILE_SIMPLE) {

         av_log(avctx, AV_LOG_INFO,

                "RANGERED should be set to 0 in Simple Profile\n");

     }

     v->s.max_b_frames = avctx->max_b_frames = get_bits(gb, 3); //common
     v->quantizer_mode = get_bits(gb, 2); //common
 

     v->finterpflag = get_bits1(gb); //common

 
     if (v->res_sprite) {

         int w = get_bits(gb, 11);
         int h = get_bits(gb, 11);
         avcodec_set_dimensions(v->s.avctx, w, h);

         skip_bits(gb, 5); //frame rate
         v->res_x8 = get_bits1(gb);
         if (get_bits1(gb)) { // something to do with DC VLC selection
             av_log(avctx, AV_LOG_ERROR, "Unsupported sprite feature\n");
             return -1;
         }
         skip_bits(gb, 3); //slice code
         v->res_rtm_flag = 0;
     } else {
         v->res_rtm_flag = get_bits1(gb); //reserved
     }

     if (!v->res_rtm_flag) {

 //            av_log(avctx, AV_LOG_ERROR,
 //                   "0 for reserved RES_RTM_FLAG is forbidden\n");

         av_log(avctx, AV_LOG_ERROR,

                "Old WMV3 version detected, some frames may be decoded incorrectly\n");

         //return -1;
     }

     //TODO: figure out what they mean (always 0x402F)

     if (!v->res_fasttx)
         skip_bits(gb, 16);

     av_log(avctx, AV_LOG_DEBUG,

            "Profile %i:\nfrmrtq_postproc=%i, bitrtq_postproc=%i\n"
            "LoopFilter=%i, MultiRes=%i, FastUVMC=%i, Extended MV=%i\n"
            "Rangered=%i, VSTransform=%i, Overlap=%i, SyncMarker=%i\n"
            "DQuant=%i, Quantizer mode=%i, Max B frames=%i\n",
            v->profile, v->frmrtq_postproc, v->bitrtq_postproc,
            v->s.loop_filter, v->multires, v->fastuvmc, v->extended_mv,
            v->rangered, v->vstransform, v->overlap, v->s.resync_marker,
            v->dquant, v->quantizer_mode, avctx->max_b_frames);

     return 0;

 }
 

 static int decode_sequence_header_adv(VC1Context *v, GetBitContext *gb)
 {

     int w, h;

     v->res_rtm_flag = 1;
     v->level = get_bits(gb, 3);

     if (v->level >= 5) {

         av_log(v->s.avctx, AV_LOG_ERROR, "Reserved LEVEL %i\n",v->level);
     }
     v->chromaformat = get_bits(gb, 2);

     if (v->chromaformat != 1) {

         av_log(v->s.avctx, AV_LOG_ERROR,
                "Only 4:2:0 chroma format supported\n");
         return -1;
     }
 
     // (fps-2)/4 (->30)

     v->frmrtq_postproc       = get_bits(gb, 3); //common

     // (bitrate-32kbps)/64kbps

     v->bitrtq_postproc       = get_bits(gb, 5); //common
     v->postprocflag          = get_bits1(gb);   //common

     w = (get_bits(gb, 12) + 1) << 1;
     h = (get_bits(gb, 12) + 1) << 1;
     avcodec_set_dimensions(v->s.avctx, w, h);

     v->broadcast             = get_bits1(gb);
     v->interlace             = get_bits1(gb);
     v->tfcntrflag            = get_bits1(gb);
     v->finterpflag           = get_bits1(gb);

     skip_bits1(gb); // reserved

 
     av_log(v->s.avctx, AV_LOG_DEBUG,

            "Advanced Profile level %i:\nfrmrtq_postproc=%i, bitrtq_postproc=%i\n"
            "LoopFilter=%i, ChromaFormat=%i, Pulldown=%i, Interlace: %i\n"
            "TFCTRflag=%i, FINTERPflag=%i\n",
            v->level, v->frmrtq_postproc, v->bitrtq_postproc,
            v->s.loop_filter, v->chromaformat, v->broadcast, v->interlace,
            v->tfcntrflag, v->finterpflag);

     v->psf = get_bits1(gb);

     if (v->psf) { //PsF, 6.1.13

         av_log(v->s.avctx, AV_LOG_ERROR, "Progressive Segmented Frame mode: not supported (yet)\n");
         return -1;
     }

     v->s.max_b_frames = v->s.avctx->max_b_frames = 7;

     if (get_bits1(gb)) { //Display Info - decoding is not affected by it

         int w, h, ar = 0;

         av_log(v->s.avctx, AV_LOG_DEBUG, "Display extended info:\n");

         w = get_bits(gb, 14) + 1;
         h = get_bits(gb, 14) + 1;

         av_log(v->s.avctx, AV_LOG_DEBUG, "Display dimensions: %ix%i\n", w, h);

         if (get_bits1(gb))

             ar = get_bits(gb, 4);

         if (ar && ar < 14) {

             v->s.avctx->sample_aspect_ratio = ff_vc1_pixel_aspect[ar];

         } else if (ar == 15) {

             w = get_bits(gb, 8) + 1;
             h = get_bits(gb, 8) + 1;

             v->s.avctx->sample_aspect_ratio = (AVRational){w, h};

         } else {
             av_reduce(&v->s.avctx->sample_aspect_ratio.num,
                       &v->s.avctx->sample_aspect_ratio.den,
                       v->s.avctx->height * w,
                       v->s.avctx->width * h,

                       1 << 30);

         }

         av_log(v->s.avctx, AV_LOG_DEBUG, "Aspect: %i:%i\n",
                v->s.avctx->sample_aspect_ratio.num,
                v->s.avctx->sample_aspect_ratio.den);

         if (get_bits1(gb)) { //framerate stuff
             if (get_bits1(gb)) {

                 v->s.avctx->time_base.num = 32;
                 v->s.avctx->time_base.den = get_bits(gb, 16) + 1;

             } else {

                 int nr, dr;
                 nr = get_bits(gb, 8);
                 dr = get_bits(gb, 4);

                 if (nr && nr < 8 && dr && dr < 3) {

                     v->s.avctx->time_base.num = ff_vc1_fps_dr[dr - 1];
                     v->s.avctx->time_base.den = ff_vc1_fps_nr[nr - 1] * 1000;

                 }

             }

             if (v->broadcast) { // Pulldown may be present
                 v->s.avctx->time_base.den  *= 2;

                 v->s.avctx->ticks_per_frame = 2;
             }

         }
 

         if (get_bits1(gb)) {
             v->color_prim    = get_bits(gb, 8);

             v->transfer_char = get_bits(gb, 8);

             v->matrix_coef   = get_bits(gb, 8);

         }
     }
 
     v->hrd_param_flag = get_bits1(gb);

     if (v->hrd_param_flag) {

         int i;
         v->hrd_num_leaky_buckets = get_bits(gb, 5);

         skip_bits(gb, 4); //bitrate exponent
         skip_bits(gb, 4); //buffer size exponent

         for (i = 0; i < v->hrd_num_leaky_buckets; i++) {

             skip_bits(gb, 16); //hrd_rate[n]
             skip_bits(gb, 16); //hrd_buffer[n]

         }
     }
     return 0;
 }
 

 int vc1_decode_entry_point(AVCodecContext *avctx, VC1Context *v, GetBitContext *gb)

 {

     int i;

 
     av_log(avctx, AV_LOG_DEBUG, "Entry point: %08X\n", show_bits_long(gb, 32));

     v->broken_link    = get_bits1(gb);
     v->closed_entry   = get_bits1(gb);
     v->panscanflag    = get_bits1(gb);
     v->refdist_flag   = get_bits1(gb);
     v->s.loop_filter  = get_bits1(gb);
     v->fastuvmc       = get_bits1(gb);
     v->extended_mv    = get_bits1(gb);
     v->dquant         = get_bits(gb, 2);
     v->vstransform    = get_bits1(gb);
     v->overlap        = get_bits1(gb);

     v->quantizer_mode = get_bits(gb, 2);
 

     if (v->hrd_param_flag) {
         for (i = 0; i < v->hrd_num_leaky_buckets; i++) {

             skip_bits(gb, 8); //hrd_full[n]

         }
     }
 
     if(get_bits1(gb)){

         int w = (get_bits(gb, 12)+1)<<1;
         int h = (get_bits(gb, 12)+1)<<1;
         avcodec_set_dimensions(avctx, w, h);

     }

     if (v->extended_mv)

         v->extended_dmv = get_bits1(gb);

     if ((v->range_mapy_flag = get_bits1(gb))) {

         av_log(avctx, AV_LOG_ERROR, "Luma scaling is not supported, expect wrong picture\n");

         v->range_mapy = get_bits(gb, 3);

     }

     if ((v->range_mapuv_flag = get_bits1(gb))) {

         av_log(avctx, AV_LOG_ERROR, "Chroma scaling is not supported, expect wrong picture\n");

         v->range_mapuv = get_bits(gb, 3);

     }
 

     av_log(avctx, AV_LOG_DEBUG, "Entry point info:\n"

            "BrokenLink=%i, ClosedEntry=%i, PanscanFlag=%i\n"
            "RefDist=%i, Postproc=%i, FastUVMC=%i, ExtMV=%i\n"
            "DQuant=%i, VSTransform=%i, Overlap=%i, Qmode=%i\n",
            v->broken_link, v->closed_entry, v->panscanflag, v->refdist_flag, v->s.loop_filter,
            v->fastuvmc, v->extended_mv, v->dquant, v->vstransform, v->overlap, v->quantizer_mode);

     return 0;
 }

 int vc1_parse_frame_header(VC1Context *v, GetBitContext* gb)

 {

     int pqindex, lowquant, status;

     v->field_mode = 0;
     v->fcm = 0;

     if (v->finterpflag)
         v->interpfrm = get_bits1(gb);

     skip_bits(gb, 2); //framecnt unused
     v->rangeredfrm = 0;

     if (v->rangered)
         v->rangeredfrm = get_bits1(gb);

     v->s.pict_type = get_bits1(gb);

     if (v->s.avctx->max_b_frames) {
         if (!v->s.pict_type) {

             if (get_bits1(gb))
                 v->s.pict_type = AV_PICTURE_TYPE_I;
             else
                 v->s.pict_type = AV_PICTURE_TYPE_B;
         } else
             v->s.pict_type = AV_PICTURE_TYPE_P;
     } else
         v->s.pict_type = v->s.pict_type ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I;

     v->bi_type = 0;

     if (v->s.pict_type == AV_PICTURE_TYPE_B) {

         v->bfraction_lut_index = get_vlc2(gb, ff_vc1_bfraction_vlc.table, VC1_BFRACTION_VLC_BITS, 1);

         v->bfraction           = ff_vc1_bfraction_lut[v->bfraction_lut_index];
         if (v->bfraction == 0) {

             v->s.pict_type = AV_PICTURE_TYPE_BI;

         }
     }

     if (v->s.pict_type == AV_PICTURE_TYPE_I || v->s.pict_type == AV_PICTURE_TYPE_BI)

         skip_bits(gb, 7); // skip buffer fullness

     if (v->parse_only)

         return 0;
 

     /* calculate RND */

     if (v->s.pict_type == AV_PICTURE_TYPE_I || v->s.pict_type == AV_PICTURE_TYPE_BI)

         v->rnd = 1;

     if (v->s.pict_type == AV_PICTURE_TYPE_P)

         v->rnd ^= 1;
 

     /* Quantizer stuff */
     pqindex = get_bits(gb, 5);

     if (!pqindex)
         return -1;

     if (v->quantizer_mode == QUANT_FRAME_IMPLICIT)

         v->pq = ff_vc1_pquant_table[0][pqindex];

     else

         v->pq = ff_vc1_pquant_table[1][pqindex];

     v->pquantizer = 1;

     if (v->quantizer_mode == QUANT_FRAME_IMPLICIT)
         v->pquantizer = pqindex < 9;

     if (v->quantizer_mode == QUANT_NON_UNIFORM)
         v->pquantizer = 0;

     v->pqindex = pqindex;

     if (pqindex < 9)
         v->halfpq = get_bits1(gb);
     else
         v->halfpq = 0;

     if (v->quantizer_mode == QUANT_FRAME_EXPLICIT)

         v->pquantizer = get_bits1(gb);

     v->dquantfrm = 0;

     if (v->extended_mv == 1)
         v->mvrange = get_unary(gb, 0, 3);

     v->k_x = v->mvrange + 9 + (v->mvrange >> 1); //k_x can be 9 10 12 13
     v->k_y = v->mvrange + 8; //k_y can be 8 9 10 11
     v->range_x = 1 << (v->k_x - 1);
     v->range_y = 1 << (v->k_y - 1);

     if (v->multires && v->s.pict_type != AV_PICTURE_TYPE_B)
         v->respic = get_bits(gb, 2);

     if (v->res_x8 && (v->s.pict_type == AV_PICTURE_TYPE_I || v->s.pict_type == AV_PICTURE_TYPE_BI)) {

         v->x8_type = get_bits1(gb);

     } else
         v->x8_type = 0;

 //av_log(v->s.avctx, AV_LOG_INFO, "%c Frame: QP=[%i]%i (+%i/2) %i\n",

 //        (v->s.pict_type == AV_PICTURE_TYPE_P) ? 'P' : ((v->s.pict_type == AV_PICTURE_TYPE_I) ? 'I' : 'B'), pqindex, v->pq, v->halfpq, v->rangeredfrm);

     if (v->s.pict_type == AV_PICTURE_TYPE_I || v->s.pict_type == AV_PICTURE_TYPE_P)
         v->use_ic = 0;

     switch (v->s.pict_type) {

     case AV_PICTURE_TYPE_P:

         if (v->pq < 5)       v->tt_index = 0;
         else if (v->pq < 13) v->tt_index = 1;
         else                 v->tt_index = 2;

 
         lowquant = (v->pq > 12) ? 0 : 1;

         v->mv_mode = ff_vc1_mv_pmode_table[lowquant][get_unary(gb, 1, 4)];

         if (v->mv_mode == MV_PMODE_INTENSITY_COMP) {

             int scale, shift, i;

             v->mv_mode2 = ff_vc1_mv_pmode_table2[lowquant][get_unary(gb, 1, 3)];

             v->lumscale = get_bits(gb, 6);
             v->lumshift = get_bits(gb, 6);

             v->use_ic   = 1;

             /* fill lookup tables for intensity compensation */

             if (!v->lumscale) {

                 scale = -64;
                 shift = (255 - v->lumshift * 2) << 6;

                 if (v->lumshift > 31)

                     shift += 128 << 6;
             } else {
                 scale = v->lumscale + 32;

                 if (v->lumshift > 31)

                     shift = (v->lumshift - 64) << 6;
                 else
                     shift = v->lumshift << 6;
             }

             for (i = 0; i < 256; i++) {
                 v->luty[i]  = av_clip_uint8((scale * i + shift + 32) >> 6);

                 v->lutuv[i] = av_clip_uint8((scale * (i - 128) + 128*64 + 32) >> 6);

             }

         }

         v->qs_last = v->s.quarter_sample;

         if (v->mv_mode == MV_PMODE_1MV_HPEL || v->mv_mode == MV_PMODE_1MV_HPEL_BILIN)

             v->s.quarter_sample = 0;

         else if (v->mv_mode == MV_PMODE_INTENSITY_COMP) {
             if (v->mv_mode2 == MV_PMODE_1MV_HPEL || v->mv_mode2 == MV_PMODE_1MV_HPEL_BILIN)

                 v->s.quarter_sample = 0;
             else
                 v->s.quarter_sample = 1;
         } else

             v->s.quarter_sample = 1;

         v->s.mspel = !(v->mv_mode == MV_PMODE_1MV_HPEL_BILIN || (v->mv_mode == MV_PMODE_INTENSITY_COMP && v->mv_mode2 == MV_PMODE_1MV_HPEL_BILIN));

         if ((v->mv_mode  == MV_PMODE_INTENSITY_COMP &&
              v->mv_mode2 == MV_PMODE_MIXED_MV)      ||
             v->mv_mode   == MV_PMODE_MIXED_MV) {

             status = bitplane_decoding(v->mv_type_mb_plane, &v->mv_type_is_raw, v);

             if (status < 0)
                 return -1;

             av_log(v->s.avctx, AV_LOG_DEBUG, "MB MV Type plane encoding: "
                    "Imode: %i, Invert: %i\n", status>>1, status&1);

         } else {
             v->mv_type_is_raw = 0;
             memset(v->mv_type_mb_plane, 0, v->s.mb_stride * v->s.mb_height);

         }

         status = bitplane_decoding(v->s.mbskip_table, &v->skip_is_raw, v);

         if (status < 0)
             return -1;

         av_log(v->s.avctx, AV_LOG_DEBUG, "MB Skip plane encoding: "
                "Imode: %i, Invert: %i\n", status>>1, status&1);

         /* Hopefully this is correct for P frames */

         v->s.mv_table_index = get_bits(gb, 2); //but using ff_vc1_ tables
         v->cbpcy_vlc = &ff_vc1_cbpcy_p_vlc[get_bits(gb, 2)];

         if (v->dquant) {

             av_log(v->s.avctx, AV_LOG_DEBUG, "VOP DQuant info\n");
             vop_dquant_decoding(v);
         }

         v->ttfrm = 0; //FIXME Is that so ?

         if (v->vstransform) {

             v->ttmbf = get_bits1(gb);

             if (v->ttmbf) {

                 v->ttfrm = ff_vc1_ttfrm_to_tt[get_bits(gb, 2)];

             }

         } else {
             v->ttmbf = 1;
             v->ttfrm = TT_8X8;

         }
         break;

     case AV_PICTURE_TYPE_B:

         if (v->pq < 5)       v->tt_index = 0;
         else if (v->pq < 13) v->tt_index = 1;
         else                 v->tt_index = 2;

         v->mv_mode          = get_bits1(gb) ? MV_PMODE_1MV : MV_PMODE_1MV_HPEL_BILIN;
         v->qs_last          = v->s.quarter_sample;

         v->s.quarter_sample = (v->mv_mode == MV_PMODE_1MV);

         v->s.mspel          = v->s.quarter_sample;

 
         status = bitplane_decoding(v->direct_mb_plane, &v->dmb_is_raw, v);

         if (status < 0)
             return -1;

         av_log(v->s.avctx, AV_LOG_DEBUG, "MB Direct Type plane encoding: "
                "Imode: %i, Invert: %i\n", status>>1, status&1);
         status = bitplane_decoding(v->s.mbskip_table, &v->skip_is_raw, v);

         if (status < 0)
             return -1;

         av_log(v->s.avctx, AV_LOG_DEBUG, "MB Skip plane encoding: "
                "Imode: %i, Invert: %i\n", status>>1, status&1);
 
         v->s.mv_table_index = get_bits(gb, 2);

         v->cbpcy_vlc        = &ff_vc1_cbpcy_p_vlc[get_bits(gb, 2)];

         if (v->dquant) {

             av_log(v->s.avctx, AV_LOG_DEBUG, "VOP DQuant info\n");
             vop_dquant_decoding(v);
         }
 
         v->ttfrm = 0;

         if (v->vstransform) {

             v->ttmbf = get_bits1(gb);

             if (v->ttmbf) {

                 v->ttfrm = ff_vc1_ttfrm_to_tt[get_bits(gb, 2)];

             }
         } else {
             v->ttmbf = 1;
             v->ttfrm = TT_8X8;
         }

         break;

     }
 

     if (!v->x8_type) {

         /* AC Syntax */
         v->c_ac_table_index = decode012(gb);

         if (v->s.pict_type == AV_PICTURE_TYPE_I || v->s.pict_type == AV_PICTURE_TYPE_BI) {

             v->y_ac_table_index = decode012(gb);
         }
         /* DC Syntax */
         v->s.dc_table_index = get_bits1(gb);

     }
 

     if (v->s.pict_type == AV_PICTURE_TYPE_BI) {

         v->s.pict_type = AV_PICTURE_TYPE_B;

         v->bi_type     = 1;

     }

     return 0;
 }

 /* fill lookup tables for intensity compensation */
 #define INIT_LUT(lumscale, lumshift, luty, lutuv)   \
     if (!lumscale) {                                \
         scale = -64;                                \
         shift = (255 - lumshift * 2) << 6;          \
         if (lumshift > 31)                          \
             shift += 128 << 6;                      \
     } else {                                        \
         scale = lumscale + 32;                      \
         if (lumshift > 31)                          \
             shift = (lumshift - 64) << 6;           \
         else                                        \
             shift = lumshift << 6;                  \
     }                                               \
     for (i = 0; i < 256; i++) {                     \
         luty[i]  = av_clip_uint8((scale * i + shift + 32) >> 6);           \
         lutuv[i] = av_clip_uint8((scale * (i - 128) + 128*64 + 32) >> 6);  \
     }
 

 int vc1_parse_frame_header_adv(VC1Context *v, GetBitContext* gb)

 {
     int pqindex, lowquant;
     int status;

     int mbmodetab, imvtab, icbptab, twomvbptab, fourmvbptab; /* useful only for debugging */
     int scale, shift, i; /* for initializing LUT for intensity compensation */

     v->numref=0;

     v->p_frame_skipped = 0;

     if (v->second_field) {

         if(v->fcm!=2 || v->field_mode!=1)
             return -1;

         v->s.pict_type = (v->fptype & 1) ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I;
         if (v->fptype & 4)
             v->s.pict_type = (v->fptype & 1) ? AV_PICTURE_TYPE_BI : AV_PICTURE_TYPE_B;
         v->s.current_picture_ptr->f.pict_type = v->s.pict_type;
         if (!v->pic_header_flag)
             goto parse_common_info;
     }

     v->field_mode = 0;

     if (v->interlace) {

         v->fcm = decode012(gb);

         if (v->fcm) {

             if (v->fcm == ILACE_FIELD)

                 v->field_mode = 1;
             if (!v->warn_interlaced++)

                 av_log(v->s.avctx, AV_LOG_ERROR,
                        "Interlaced frames/fields support is incomplete\n");

         }

     } else {

         v->fcm = PROGRESSIVE;

     }

 
     if (v->field_mode) {
         v->fptype = get_bits(gb, 3);
         v->s.pict_type = (v->fptype & 2) ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I;
         if (v->fptype & 4) // B-picture
             v->s.pict_type = (v->fptype & 2) ? AV_PICTURE_TYPE_BI : AV_PICTURE_TYPE_B;
     } else {

         switch (get_unary(gb, 0, 4)) {

         case 0:
             v->s.pict_type = AV_PICTURE_TYPE_P;
             break;
         case 1:
             v->s.pict_type = AV_PICTURE_TYPE_B;
             break;
         case 2:
             v->s.pict_type = AV_PICTURE_TYPE_I;
             break;
         case 3:
             v->s.pict_type = AV_PICTURE_TYPE_BI;
             break;
         case 4:
             v->s.pict_type = AV_PICTURE_TYPE_P; // skipped pic
             v->p_frame_skipped = 1;
             break;
         }

     }

     if (v->tfcntrflag)

         skip_bits(gb, 8);

     if (v->broadcast) {
         if (!v->interlace || v->psf) {

             v->rptfrm = get_bits(gb, 2);

         } else {

             v->tff = get_bits1(gb);

             v->rff = get_bits1(gb);

         }
     }

     if (v->panscanflag) {

         av_log_missing_feature(v->s.avctx, "Pan-scan", 0);

         //...
     }

     if (v->p_frame_skipped) {

         return 0;
     }

     v->rnd = get_bits1(gb);

     if (v->interlace)

         v->uvsamp = get_bits1(gb);

     if(!ff_vc1_bfraction_vlc.table)
         return 0; //parsing only, vlc tables havnt been allocated

     if (v->field_mode) {
         if (!v->refdist_flag)
             v->refdist = 0;
         else {
             if ((v->s.pict_type != AV_PICTURE_TYPE_B)
                 && (v->s.pict_type != AV_PICTURE_TYPE_BI)) {
                 v->refdist = get_bits(gb, 2);
                 if (v->refdist == 3)
                     v->refdist += get_unary(gb, 0, 16);
             } else {
                 v->bfraction_lut_index = get_vlc2(gb, ff_vc1_bfraction_vlc.table, VC1_BFRACTION_VLC_BITS, 1);

                 v->bfraction           = ff_vc1_bfraction_lut[v->bfraction_lut_index];

                 v->frfd = (v->bfraction * v->refdist) >> 8;
                 v->brfd = v->refdist - v->frfd - 1;
                 if (v->brfd < 0)
                     v->brfd = 0;
             }
         }
         goto parse_common_info;
     }

     if (v->finterpflag)
         v->interpfrm = get_bits1(gb);
     if (v->s.pict_type == AV_PICTURE_TYPE_B) {

         v->bfraction_lut_index = get_vlc2(gb, ff_vc1_bfraction_vlc.table, VC1_BFRACTION_VLC_BITS, 1);

         v->bfraction           = ff_vc1_bfraction_lut[v->bfraction_lut_index];
         if (v->bfraction == 0) {

             v->s.pict_type = AV_PICTURE_TYPE_BI; /* XXX: should not happen here */

         }
     }

 
     parse_common_info:
     if (v->field_mode)
         v->cur_field_type = !(v->tff ^ v->second_field);

     pqindex = get_bits(gb, 5);

     if (!pqindex)
         return -1;

     v->pqindex = pqindex;
     if (v->quantizer_mode == QUANT_FRAME_IMPLICIT)

         v->pq = ff_vc1_pquant_table[0][pqindex];

     else

         v->pq = ff_vc1_pquant_table[1][pqindex];

 
     v->pquantizer = 1;
     if (v->quantizer_mode == QUANT_FRAME_IMPLICIT)
         v->pquantizer = pqindex < 9;
     if (v->quantizer_mode == QUANT_NON_UNIFORM)
         v->pquantizer = 0;
     v->pqindex = pqindex;

     if (pqindex < 9)
         v->halfpq = get_bits1(gb);
     else
         v->halfpq = 0;

     if (v->quantizer_mode == QUANT_FRAME_EXPLICIT)

         v->pquantizer = get_bits1(gb);

     if (v->postprocflag)

         v->postproc = get_bits(gb, 2);

     if (v->s.pict_type == AV_PICTURE_TYPE_I || v->s.pict_type == AV_PICTURE_TYPE_P)

         v->use_ic = 0;

     if (v->parse_only)

         return 0;
 

     switch (v->s.pict_type) {

     case AV_PICTURE_TYPE_I:
     case AV_PICTURE_TYPE_BI:

         if (v->fcm == ILACE_FRAME) { //interlace frame picture

             status = bitplane_decoding(v->fieldtx_plane, &v->fieldtx_is_raw, v);
             if (status < 0)
                 return -1;
             av_log(v->s.avctx, AV_LOG_DEBUG, "FIELDTX plane encoding: "
                    "Imode: %i, Invert: %i\n", status>>1, status&1);
         }

         status = bitplane_decoding(v->acpred_plane, &v->acpred_is_raw, v);

         if (status < 0)
             return -1;

         av_log(v->s.avctx, AV_LOG_DEBUG, "ACPRED plane encoding: "

                "Imode: %i, Invert: %i\n", status>>1, status&1);

         v->condover = CONDOVER_NONE;

         if (v->overlap && v->pq <= 8) {

             v->condover = decode012(gb);

             if (v->condover == CONDOVER_SELECT) {

                 status = bitplane_decoding(v->over_flags_plane, &v->overflg_is_raw, v);

                 if (status < 0)
                     return -1;

                 av_log(v->s.avctx, AV_LOG_DEBUG, "CONDOVER plane encoding: "

                        "Imode: %i, Invert: %i\n", status>>1, status&1);

             }
         }
         break;

     case AV_PICTURE_TYPE_P:

         if (v->field_mode) {
             v->numref = get_bits1(gb);
             if (!v->numref) {

                 v->reffield          = get_bits1(gb);

                 v->ref_field_type[0] = v->reffield ^ !v->cur_field_type;
             }
         }
         if (v->extended_mv)
             v->mvrange = get_unary(gb, 0, 3);
         else
             v->mvrange = 0;
         if (v->interlace) {
             if (v->extended_dmv)
                 v->dmvrange = get_unary(gb, 0, 3);
             else
                 v->dmvrange = 0;

             if (v->fcm == ILACE_FRAME) { // interlaced frame picture

                 v->fourmvswitch = get_bits1(gb);

                 v->intcomp      = get_bits1(gb);

                 if (v->intcomp) {
                     v->lumscale = get_bits(gb, 6);
                     v->lumshift = get_bits(gb, 6);
                     INIT_LUT(v->lumscale, v->lumshift, v->luty, v->lutuv);
                 }
                 status = bitplane_decoding(v->s.mbskip_table, &v->skip_is_raw, v);
                 av_log(v->s.avctx, AV_LOG_DEBUG, "SKIPMB plane encoding: "

                        "Imode: %i, Invert: %i\n", status>>1, status&1);

                 mbmodetab = get_bits(gb, 2);
                 if (v->fourmvswitch)
                     v->mbmode_vlc = &ff_vc1_intfr_4mv_mbmode_vlc[mbmodetab];
                 else
                     v->mbmode_vlc = &ff_vc1_intfr_non4mv_mbmode_vlc[mbmodetab];

                 imvtab         = get_bits(gb, 2);
                 v->imv_vlc     = &ff_vc1_1ref_mvdata_vlc[imvtab];

                 // interlaced p-picture cbpcy range is [1, 63]

                 icbptab        = get_bits(gb, 3);
                 v->cbpcy_vlc   = &ff_vc1_icbpcy_vlc[icbptab];
                 twomvbptab     = get_bits(gb, 2);

                 v->twomvbp_vlc = &ff_vc1_2mv_block_pattern_vlc[twomvbptab];
                 if (v->fourmvswitch) {

                     fourmvbptab     = get_bits(gb, 2);

                     v->fourmvbp_vlc = &ff_vc1_4mv_block_pattern_vlc[fourmvbptab];
                 }
             }
         }

         v->k_x = v->mvrange + 9 + (v->mvrange >> 1); //k_x can be 9 10 12 13
         v->k_y = v->mvrange + 8; //k_y can be 8 9 10 11
         v->range_x = 1 << (v->k_x - 1);
         v->range_y = 1 << (v->k_y - 1);
 

         if (v->pq < 5)
             v->tt_index = 0;

         else if (v->pq < 13)

             v->tt_index = 1;
         else
             v->tt_index = 2;

         if (v->fcm != ILACE_FRAME) {

             int mvmode;

             mvmode     = get_unary(gb, 1, 4);
             lowquant   = (v->pq > 12) ? 0 : 1;

             v->mv_mode = ff_vc1_mv_pmode_table[lowquant][mvmode];
             if (v->mv_mode == MV_PMODE_INTENSITY_COMP) {
                 int mvmode2;
                 mvmode2 = get_unary(gb, 1, 3);
                 v->mv_mode2 = ff_vc1_mv_pmode_table2[lowquant][mvmode2];
                 if (v->field_mode)
                     v->intcompfield = decode210(gb);
                 v->lumscale = get_bits(gb, 6);
                 v->lumshift = get_bits(gb, 6);
                 INIT_LUT(v->lumscale, v->lumshift, v->luty, v->lutuv);
                 if ((v->field_mode) && !v->intcompfield) {
                     v->lumscale2 = get_bits(gb, 6);
                     v->lumshift2 = get_bits(gb, 6);
                     INIT_LUT(v->lumscale2, v->lumshift2, v->luty2, v->lutuv2);
                 }
                 v->use_ic = 1;

             }

             v->qs_last = v->s.quarter_sample;

             if (v->mv_mode == MV_PMODE_1MV_HPEL || v->mv_mode == MV_PMODE_1MV_HPEL_BILIN)

                 v->s.quarter_sample = 0;

             else if (v->mv_mode == MV_PMODE_INTENSITY_COMP) {
                 if (v->mv_mode2 == MV_PMODE_1MV_HPEL || v->mv_mode2 == MV_PMODE_1MV_HPEL_BILIN)

                     v->s.quarter_sample = 0;
                 else
                     v->s.quarter_sample = 1;
             } else

                 v->s.quarter_sample = 1;

             v->s.mspel = !(v->mv_mode == MV_PMODE_1MV_HPEL_BILIN
                            || (v->mv_mode == MV_PMODE_INTENSITY_COMP
                                && v->mv_mode2 == MV_PMODE_1MV_HPEL_BILIN));

         }

         if (v->fcm == PROGRESSIVE) { // progressive

             if ((v->mv_mode == MV_PMODE_INTENSITY_COMP &&

                  v->mv_mode2 == MV_PMODE_MIXED_MV)

                 || v->mv_mode == MV_PMODE_MIXED_MV) {

                 status = bitplane_decoding(v->mv_type_mb_plane, &v->mv_type_is_raw, v);
                 if (status < 0)
                     return -1;
                 av_log(v->s.avctx, AV_LOG_DEBUG, "MB MV Type plane encoding: "

                        "Imode: %i, Invert: %i\n", status>>1, status&1);

             } else {
                 v->mv_type_is_raw = 0;
                 memset(v->mv_type_mb_plane, 0, v->s.mb_stride * v->s.mb_height);
             }
             status = bitplane_decoding(v->s.mbskip_table, &v->skip_is_raw, v);
             if (status < 0)
                 return -1;
             av_log(v->s.avctx, AV_LOG_DEBUG, "MB Skip plane encoding: "

                    "Imode: %i, Invert: %i\n", status>>1, status&1);
 

             /* Hopefully this is correct for P frames */
             v->s.mv_table_index = get_bits(gb, 2); //but using ff_vc1_ tables

             v->cbpcy_vlc        = &ff_vc1_cbpcy_p_vlc[get_bits(gb, 2)];

         } else if (v->fcm == ILACE_FRAME) { // frame interlaced

             v->qs_last          = v->s.quarter_sample;

             v->s.quarter_sample = 1;

             v->s.mspel          = 1;

         } else {    // field interlaced
             mbmodetab = get_bits(gb, 3);
             imvtab = get_bits(gb, 2 + v->numref);
             if (!v->numref)
                 v->imv_vlc = &ff_vc1_1ref_mvdata_vlc[imvtab];
             else
                 v->imv_vlc = &ff_vc1_2ref_mvdata_vlc[imvtab];
             icbptab = get_bits(gb, 3);
             v->cbpcy_vlc = &ff_vc1_icbpcy_vlc[icbptab];
             if ((v->mv_mode == MV_PMODE_INTENSITY_COMP &&
                 v->mv_mode2 == MV_PMODE_MIXED_MV) || v->mv_mode == MV_PMODE_MIXED_MV) {

                 fourmvbptab     = get_bits(gb, 2);

                 v->fourmvbp_vlc = &ff_vc1_4mv_block_pattern_vlc[fourmvbptab];
                 v->mbmode_vlc = &ff_vc1_if_mmv_mbmode_vlc[mbmodetab];
             } else {
                 v->mbmode_vlc = &ff_vc1_if_1mv_mbmode_vlc[mbmodetab];
             }

         }

         if (v->dquant) {

             av_log(v->s.avctx, AV_LOG_DEBUG, "VOP DQuant info\n");
             vop_dquant_decoding(v);
         }
 
         v->ttfrm = 0; //FIXME Is that so ?

         if (v->vstransform) {

             v->ttmbf = get_bits1(gb);

             if (v->ttmbf) {

                 v->ttfrm = ff_vc1_ttfrm_to_tt[get_bits(gb, 2)];

             }
         } else {
             v->ttmbf = 1;
             v->ttfrm = TT_8X8;
         }
         break;

     case AV_PICTURE_TYPE_B:

         // TODO: implement interlaced frame B picture decoding

         if (v->fcm == ILACE_FRAME)

             return -1;
         if (v->extended_mv)
             v->mvrange = get_unary(gb, 0, 3);
         else
             v->mvrange = 0;

         v->k_x     = v->mvrange + 9 + (v->mvrange >> 1); //k_x can be 9 10 12 13
         v->k_y     = v->mvrange + 8; //k_y can be 8 9 10 11

         v->range_x = 1 << (v->k_x - 1);
         v->range_y = 1 << (v->k_y - 1);
 

         if (v->pq < 5)
             v->tt_index = 0;

         else if (v->pq < 13)

             v->tt_index = 1;
         else
             v->tt_index = 2;
 
         if (v->field_mode) {
             int mvmode;

             av_log(v->s.avctx, AV_LOG_ERROR, "B Fields do not work currently\n");
             return -1;

             if (v->extended_dmv)
                 v->dmvrange = get_unary(gb, 0, 3);
             mvmode = get_unary(gb, 1, 3);
             lowquant = (v->pq > 12) ? 0 : 1;

             v->mv_mode          = ff_vc1_mv_pmode_table2[lowquant][mvmode];
             v->qs_last          = v->s.quarter_sample;

             v->s.quarter_sample = (v->mv_mode == MV_PMODE_1MV || v->mv_mode == MV_PMODE_MIXED_MV);

             v->s.mspel          = !(v->mv_mode == MV_PMODE_1MV_HPEL_BILIN || v->mv_mode == MV_PMODE_1MV_HPEL);

             status = bitplane_decoding(v->forward_mb_plane, &v->fmb_is_raw, v);
             if (status < 0)
                 return -1;
             av_log(v->s.avctx, AV_LOG_DEBUG, "MB Forward Type plane encoding: "
                    "Imode: %i, Invert: %i\n", status>>1, status&1);
             mbmodetab = get_bits(gb, 3);
             if (v->mv_mode == MV_PMODE_MIXED_MV)
                 v->mbmode_vlc = &ff_vc1_if_mmv_mbmode_vlc[mbmodetab];
             else
                 v->mbmode_vlc = &ff_vc1_if_1mv_mbmode_vlc[mbmodetab];

             imvtab       = get_bits(gb, 3);
             v->imv_vlc   = &ff_vc1_2ref_mvdata_vlc[imvtab];
             icbptab      = get_bits(gb, 3);

             v->cbpcy_vlc = &ff_vc1_icbpcy_vlc[icbptab];
             if (v->mv_mode == MV_PMODE_MIXED_MV) {

                 fourmvbptab     = get_bits(gb, 2);

                 v->fourmvbp_vlc = &ff_vc1_4mv_block_pattern_vlc[fourmvbptab];
             }
             v->numref = 1; // interlaced field B pictures are always 2-ref
         } else {

             v->mv_mode          = get_bits1(gb) ? MV_PMODE_1MV : MV_PMODE_1MV_HPEL_BILIN;
             v->qs_last          = v->s.quarter_sample;

             v->s.quarter_sample = (v->mv_mode == MV_PMODE_1MV);

             v->s.mspel          = v->s.quarter_sample;
             status              = bitplane_decoding(v->direct_mb_plane, &v->dmb_is_raw, v);

             if (status < 0)
                 return -1;
             av_log(v->s.avctx, AV_LOG_DEBUG, "MB Direct Type plane encoding: "
                    "Imode: %i, Invert: %i\n", status>>1, status&1);
             status = bitplane_decoding(v->s.mbskip_table, &v->skip_is_raw, v);
             if (status < 0)
                 return -1;
             av_log(v->s.avctx, AV_LOG_DEBUG, "MB Skip plane encoding: "
                    "Imode: %i, Invert: %i\n", status>>1, status&1);
             v->s.mv_table_index = get_bits(gb, 2);
             v->cbpcy_vlc = &ff_vc1_cbpcy_p_vlc[get_bits(gb, 2)];
         }

         if (v->dquant) {

             av_log(v->s.avctx, AV_LOG_DEBUG, "VOP DQuant info\n");
             vop_dquant_decoding(v);
         }
 
         v->ttfrm = 0;

         if (v->vstransform) {

             v->ttmbf = get_bits1(gb);

             if (v->ttmbf) {

                 v->ttfrm = ff_vc1_ttfrm_to_tt[get_bits(gb, 2)];

             }
         } else {
             v->ttmbf = 1;
             v->ttfrm = TT_8X8;
         }
         break;

     }
 
     /* AC Syntax */
     v->c_ac_table_index = decode012(gb);

     if (v->s.pict_type == AV_PICTURE_TYPE_I || v->s.pict_type == AV_PICTURE_TYPE_BI) {

         v->y_ac_table_index = decode012(gb);
     }
     /* DC Syntax */

     v->s.dc_table_index = get_bits1(gb);

     if ((v->s.pict_type == AV_PICTURE_TYPE_I || v->s.pict_type == AV_PICTURE_TYPE_BI)
         && v->dquant) {

         av_log(v->s.avctx, AV_LOG_DEBUG, "VOP DQuant info\n");
         vop_dquant_decoding(v);
     }
 

     v->bi_type = 0;

     if (v->s.pict_type == AV_PICTURE_TYPE_BI) {

         v->s.pict_type = AV_PICTURE_TYPE_B;

         v->bi_type = 1;
     }

     return 0;
 }