libavcodec/indeo4.c
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00001 /*
00002  * Indeo Video Interactive v4 compatible decoder
00003  * Copyright (c) 2009-2011 Maxim Poliakovski
00004  *
00005  * This file is part of Libav.
00006  *
00007  * Libav is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * Libav is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with Libav; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00030 #define BITSTREAM_READER_LE
00031 #include "avcodec.h"
00032 #include "get_bits.h"
00033 #include "dsputil.h"
00034 #include "ivi_dsp.h"
00035 #include "ivi_common.h"
00036 #include "indeo4data.h"
00037 
00041 enum {
00042     FRAMETYPE_INTRA       = 0,
00043     FRAMETYPE_BIDIR1      = 1,  
00044     FRAMETYPE_INTER       = 2,  
00045     FRAMETYPE_BIDIR       = 3,  
00046     FRAMETYPE_INTER_NOREF = 4,  
00047     FRAMETYPE_NULL_FIRST  = 5,  
00048     FRAMETYPE_NULL_LAST   = 6   
00049 };
00050 
00051 #define IVI4_PIC_SIZE_ESC   7
00052 
00053 
00054 static const struct {
00055     InvTransformPtr *inv_trans;
00056     DCTransformPtr  *dc_trans;
00057     int             is_2d_trans;
00058 } transforms[18] = {
00059     { ff_ivi_inverse_haar_8x8,  ff_ivi_dc_haar_2d,       1 },
00060     { NULL, NULL, 0 }, /* inverse Haar 8x1 */
00061     { NULL, NULL, 0 }, /* inverse Haar 1x8 */
00062     { ff_ivi_put_pixels_8x8,    ff_ivi_put_dc_pixel_8x8, 1 },
00063     { ff_ivi_inverse_slant_8x8, ff_ivi_dc_slant_2d,      1 },
00064     { ff_ivi_row_slant8,        ff_ivi_dc_row_slant,     1 },
00065     { ff_ivi_col_slant8,        ff_ivi_dc_col_slant,     1 },
00066     { NULL, NULL, 0 }, /* inverse DCT 8x8 */
00067     { NULL, NULL, 0 }, /* inverse DCT 8x1 */
00068     { NULL, NULL, 0 }, /* inverse DCT 1x8 */
00069     { NULL, NULL, 0 }, /* inverse Haar 4x4 */
00070     { ff_ivi_inverse_slant_4x4, ff_ivi_dc_slant_2d,      1 },
00071     { NULL, NULL, 0 }, /* no transform 4x4 */
00072     { NULL, NULL, 0 }, /* inverse Haar 1x4 */
00073     { NULL, NULL, 0 }, /* inverse Haar 4x1 */
00074     { NULL, NULL, 0 }, /* inverse slant 1x4 */
00075     { NULL, NULL, 0 }, /* inverse slant 4x1 */
00076     { NULL, NULL, 0 }, /* inverse DCT 4x4 */
00077 };
00078 
00089 static int decode_plane_subdivision(GetBitContext *gb)
00090 {
00091     int i;
00092 
00093     switch (get_bits(gb, 2)) {
00094     case 3:
00095         return 1;
00096     case 2:
00097         for (i = 0; i < 4; i++)
00098             if (get_bits(gb, 2) != 3)
00099                 return 0;
00100         return 4;
00101     default:
00102         return 0;
00103     }
00104 }
00105 
00106 static inline int scale_tile_size(int def_size, int size_factor)
00107 {
00108     return size_factor == 15 ? def_size : (size_factor + 1) << 5;
00109 }
00110 
00118 static int decode_pic_hdr(IVI45DecContext *ctx, AVCodecContext *avctx)
00119 {
00120     int             pic_size_indx, i, p;
00121     IVIPicConfig    pic_conf;
00122 
00123     if (get_bits(&ctx->gb, 18) != 0x3FFF8) {
00124         av_log(avctx, AV_LOG_ERROR, "Invalid picture start code!\n");
00125         return AVERROR_INVALIDDATA;
00126     }
00127 
00128     ctx->prev_frame_type = ctx->frame_type;
00129     ctx->frame_type      = get_bits(&ctx->gb, 3);
00130     if (ctx->frame_type == 7) {
00131         av_log(avctx, AV_LOG_ERROR, "Invalid frame type: %d\n", ctx->frame_type);
00132         return AVERROR_INVALIDDATA;
00133     }
00134 
00135 #if IVI4_STREAM_ANALYSER
00136     if (   ctx->frame_type == FRAMETYPE_BIDIR1
00137         || ctx->frame_type == FRAMETYPE_BIDIR)
00138         ctx->has_b_frames = 1;
00139 #endif
00140 
00141     ctx->transp_status = get_bits1(&ctx->gb);
00142 #if IVI4_STREAM_ANALYSER
00143     if (ctx->transp_status) {
00144         ctx->has_transp = 1;
00145     }
00146 #endif
00147 
00148     /* unknown bit: Mac decoder ignores this bit, XANIM returns error */
00149     if (get_bits1(&ctx->gb)) {
00150         av_log(avctx, AV_LOG_ERROR, "Sync bit is set!\n");
00151         return AVERROR_INVALIDDATA;
00152     }
00153 
00154     ctx->data_size = get_bits1(&ctx->gb) ? get_bits(&ctx->gb, 24) : 0;
00155 
00156     /* null frames don't contain anything else so we just return */
00157     if (ctx->frame_type >= FRAMETYPE_NULL_FIRST) {
00158         av_dlog(avctx, "Null frame encountered!\n");
00159         return 0;
00160     }
00161 
00162     /* Check key lock status. If enabled - ignore lock word.         */
00163     /* Usually we have to prompt the user for the password, but      */
00164     /* we don't do that because Indeo 4 videos can be decoded anyway */
00165     if (get_bits1(&ctx->gb)) {
00166         skip_bits_long(&ctx->gb, 32);
00167         av_dlog(avctx, "Password-protected clip!\n");
00168     }
00169 
00170     pic_size_indx = get_bits(&ctx->gb, 3);
00171     if (pic_size_indx == IVI4_PIC_SIZE_ESC) {
00172         pic_conf.pic_height = get_bits(&ctx->gb, 16);
00173         pic_conf.pic_width  = get_bits(&ctx->gb, 16);
00174     } else {
00175         pic_conf.pic_height = ivi4_common_pic_sizes[pic_size_indx * 2 + 1];
00176         pic_conf.pic_width  = ivi4_common_pic_sizes[pic_size_indx * 2    ];
00177     }
00178 
00179     /* Decode tile dimensions. */
00180     if (get_bits1(&ctx->gb)) {
00181         pic_conf.tile_height = scale_tile_size(pic_conf.pic_height, get_bits(&ctx->gb, 4));
00182         pic_conf.tile_width  = scale_tile_size(pic_conf.pic_width,  get_bits(&ctx->gb, 4));
00183 #if IVI4_STREAM_ANALYSER
00184         ctx->uses_tiling = 1;
00185 #endif
00186     } else {
00187         pic_conf.tile_height = pic_conf.pic_height;
00188         pic_conf.tile_width  = pic_conf.pic_width;
00189     }
00190 
00191     /* Decode chroma subsampling. We support only 4:4 aka YVU9. */
00192     if (get_bits(&ctx->gb, 2)) {
00193         av_log(avctx, AV_LOG_ERROR, "Only YVU9 picture format is supported!\n");
00194         return AVERROR_INVALIDDATA;
00195     }
00196     pic_conf.chroma_height = (pic_conf.pic_height + 3) >> 2;
00197     pic_conf.chroma_width  = (pic_conf.pic_width  + 3) >> 2;
00198 
00199     /* decode subdivision of the planes */
00200     pic_conf.luma_bands = decode_plane_subdivision(&ctx->gb);
00201     if (pic_conf.luma_bands)
00202         pic_conf.chroma_bands = decode_plane_subdivision(&ctx->gb);
00203     ctx->is_scalable = pic_conf.luma_bands != 1 || pic_conf.chroma_bands != 1;
00204     if (ctx->is_scalable && (pic_conf.luma_bands != 4 || pic_conf.chroma_bands != 1)) {
00205         av_log(avctx, AV_LOG_ERROR, "Scalability: unsupported subdivision! Luma bands: %d, chroma bands: %d\n",
00206                pic_conf.luma_bands, pic_conf.chroma_bands);
00207         return AVERROR_INVALIDDATA;
00208     }
00209 
00210     /* check if picture layout was changed and reallocate buffers */
00211     if (ivi_pic_config_cmp(&pic_conf, &ctx->pic_conf)) {
00212         if (ff_ivi_init_planes(ctx->planes, &pic_conf)) {
00213             av_log(avctx, AV_LOG_ERROR, "Couldn't reallocate color planes!\n");
00214             ctx->pic_conf.luma_bands = 0;
00215             return AVERROR(ENOMEM);
00216         }
00217 
00218         ctx->pic_conf = pic_conf;
00219 
00220         /* set default macroblock/block dimensions */
00221         for (p = 0; p <= 2; p++) {
00222             for (i = 0; i < (!p ? pic_conf.luma_bands : pic_conf.chroma_bands); i++) {
00223                 ctx->planes[p].bands[i].mb_size  = !p ? (!ctx->is_scalable ? 16 : 8) : 4;
00224                 ctx->planes[p].bands[i].blk_size = !p ? 8 : 4;
00225             }
00226         }
00227 
00228         if (ff_ivi_init_tiles(ctx->planes, ctx->pic_conf.tile_width,
00229                               ctx->pic_conf.tile_height)) {
00230             av_log(avctx, AV_LOG_ERROR,
00231                    "Couldn't reallocate internal structures!\n");
00232             return AVERROR(ENOMEM);
00233         }
00234     }
00235 
00236     ctx->frame_num = get_bits1(&ctx->gb) ? get_bits(&ctx->gb, 20) : 0;
00237 
00238     /* skip decTimeEst field if present */
00239     if (get_bits1(&ctx->gb))
00240         skip_bits(&ctx->gb, 8);
00241 
00242     /* decode macroblock and block huffman codebooks */
00243     if (ff_ivi_dec_huff_desc(&ctx->gb, get_bits1(&ctx->gb), IVI_MB_HUFF,  &ctx->mb_vlc,  avctx) ||
00244         ff_ivi_dec_huff_desc(&ctx->gb, get_bits1(&ctx->gb), IVI_BLK_HUFF, &ctx->blk_vlc, avctx))
00245         return AVERROR_INVALIDDATA;
00246 
00247     ctx->rvmap_sel = get_bits1(&ctx->gb) ? get_bits(&ctx->gb, 3) : 8;
00248 
00249     ctx->in_imf = get_bits1(&ctx->gb);
00250     ctx->in_q   = get_bits1(&ctx->gb);
00251 
00252     ctx->pic_glob_quant = get_bits(&ctx->gb, 5);
00253 
00254     /* TODO: ignore this parameter if unused */
00255     ctx->unknown1 = get_bits1(&ctx->gb) ? get_bits(&ctx->gb, 3) : 0;
00256 
00257     ctx->checksum = get_bits1(&ctx->gb) ? get_bits(&ctx->gb, 16) : 0;
00258 
00259     /* skip picture header extension if any */
00260     while (get_bits1(&ctx->gb)) {
00261         av_dlog(avctx, "Pic hdr extension encountered!\n");
00262         skip_bits(&ctx->gb, 8);
00263     }
00264 
00265     if (get_bits1(&ctx->gb)) {
00266         av_log(avctx, AV_LOG_ERROR, "Bad blocks bits encountered!\n");
00267     }
00268 
00269     align_get_bits(&ctx->gb);
00270 
00271     return 0;
00272 }
00273 
00274 
00283 static int decode_band_hdr(IVI45DecContext *ctx, IVIBandDesc *band,
00284                            AVCodecContext *avctx)
00285 {
00286     int plane, band_num, indx, transform_id, scan_indx;
00287     int i;
00288 
00289     plane    = get_bits(&ctx->gb, 2);
00290     band_num = get_bits(&ctx->gb, 4);
00291     if (band->plane != plane || band->band_num != band_num) {
00292         av_log(avctx, AV_LOG_ERROR, "Invalid band header sequence!\n");
00293         return AVERROR_INVALIDDATA;
00294     }
00295 
00296     band->is_empty = get_bits1(&ctx->gb);
00297     if (!band->is_empty) {
00298         /* skip header size
00299          * If header size is not given, header size is 4 bytes. */
00300         if (get_bits1(&ctx->gb))
00301             skip_bits(&ctx->gb, 16);
00302 
00303         band->is_halfpel = get_bits(&ctx->gb, 2);
00304         if (band->is_halfpel >= 2) {
00305             av_log(avctx, AV_LOG_ERROR, "Invalid/unsupported mv resolution: %d!\n",
00306                    band->is_halfpel);
00307             return AVERROR_INVALIDDATA;
00308         }
00309 #if IVI4_STREAM_ANALYSER
00310         if (!band->is_halfpel)
00311             ctx->uses_fullpel = 1;
00312 #endif
00313 
00314         band->checksum_present = get_bits1(&ctx->gb);
00315         if (band->checksum_present)
00316             band->checksum = get_bits(&ctx->gb, 16);
00317 
00318         indx = get_bits(&ctx->gb, 2);
00319         if (indx == 3) {
00320             av_log(avctx, AV_LOG_ERROR, "Invalid block size!\n");
00321             return AVERROR_INVALIDDATA;
00322         }
00323         band->mb_size  = 16 >> indx;
00324         band->blk_size = 8 >> (indx >> 1);
00325 
00326         band->inherit_mv     = get_bits1(&ctx->gb);
00327         band->inherit_qdelta = get_bits1(&ctx->gb);
00328 
00329         band->glob_quant = get_bits(&ctx->gb, 5);
00330 
00331         if (!get_bits1(&ctx->gb) || ctx->frame_type == FRAMETYPE_INTRA) {
00332             transform_id = get_bits(&ctx->gb, 5);
00333             if (transform_id >= FF_ARRAY_ELEMS(transforms) ||
00334                 !transforms[transform_id].inv_trans) {
00335                 av_log_ask_for_sample(avctx, "Unimplemented transform: %d!\n", transform_id);
00336                 return AVERROR_PATCHWELCOME;
00337             }
00338             if ((transform_id >= 7 && transform_id <= 9) ||
00339                  transform_id == 17) {
00340                 av_log_ask_for_sample(avctx, "DCT transform not supported yet!\n");
00341                 return AVERROR_PATCHWELCOME;
00342             }
00343 
00344 #if IVI4_STREAM_ANALYSER
00345             if ((transform_id >= 0 && transform_id <= 2) || transform_id == 10)
00346                 ctx->uses_haar = 1;
00347 #endif
00348 
00349             band->inv_transform = transforms[transform_id].inv_trans;
00350             band->dc_transform  = transforms[transform_id].dc_trans;
00351             band->is_2d_trans   = transforms[transform_id].is_2d_trans;
00352             if (transform_id < 10)
00353                 band->transform_size = 8;
00354             else
00355                 band->transform_size = 4;
00356 
00357             if (band->blk_size != band->transform_size)
00358                 return AVERROR_INVALIDDATA;
00359 
00360             scan_indx = get_bits(&ctx->gb, 4);
00361             if (scan_indx == 15) {
00362                 av_log(avctx, AV_LOG_ERROR, "Custom scan pattern encountered!\n");
00363                 return AVERROR_INVALIDDATA;
00364             }
00365             if (scan_indx > 4 && scan_indx < 10) {
00366                 if (band->blk_size != 4)
00367                     return AVERROR_INVALIDDATA;
00368             } else if (band->blk_size != 8)
00369                 return AVERROR_INVALIDDATA;
00370 
00371             band->scan = scan_index_to_tab[scan_indx];
00372 
00373             band->quant_mat = get_bits(&ctx->gb, 5);
00374             if (band->quant_mat == 31) {
00375                 av_log(avctx, AV_LOG_ERROR, "Custom quant matrix encountered!\n");
00376                 return AVERROR_INVALIDDATA;
00377             }
00378             if (band->quant_mat >= FF_ARRAY_ELEMS(quant_index_to_tab)) {
00379                 av_log_ask_for_sample(avctx, "Quantization matrix %d",
00380                                       band->quant_mat);
00381                 return AVERROR_INVALIDDATA;
00382             }
00383         }
00384 
00385         /* decode block huffman codebook */
00386         if (ff_ivi_dec_huff_desc(&ctx->gb, get_bits1(&ctx->gb), IVI_BLK_HUFF,
00387                                  &band->blk_vlc, avctx))
00388             return AVERROR_INVALIDDATA;
00389 
00390         /* select appropriate rvmap table for this band */
00391         band->rvmap_sel = get_bits1(&ctx->gb) ? get_bits(&ctx->gb, 3) : 8;
00392 
00393         /* decode rvmap probability corrections if any */
00394         band->num_corr = 0; /* there is no corrections */
00395         if (get_bits1(&ctx->gb)) {
00396             band->num_corr = get_bits(&ctx->gb, 8); /* get number of correction pairs */
00397             if (band->num_corr > 61) {
00398                 av_log(avctx, AV_LOG_ERROR, "Too many corrections: %d\n",
00399                        band->num_corr);
00400                 return AVERROR_INVALIDDATA;
00401             }
00402 
00403             /* read correction pairs */
00404             for (i = 0; i < band->num_corr * 2; i++)
00405                 band->corr[i] = get_bits(&ctx->gb, 8);
00406         }
00407     }
00408 
00409     if (band->blk_size == 8) {
00410         band->intra_base = &ivi4_quant_8x8_intra[quant_index_to_tab[band->quant_mat]][0];
00411         band->inter_base = &ivi4_quant_8x8_inter[quant_index_to_tab[band->quant_mat]][0];
00412     } else {
00413         band->intra_base = &ivi4_quant_4x4_intra[quant_index_to_tab[band->quant_mat]][0];
00414         band->inter_base = &ivi4_quant_4x4_inter[quant_index_to_tab[band->quant_mat]][0];
00415     }
00416 
00417     /* Indeo 4 doesn't use scale tables */
00418     band->intra_scale = NULL;
00419     band->inter_scale = NULL;
00420 
00421     align_get_bits(&ctx->gb);
00422 
00423     return 0;
00424 }
00425 
00426 
00437 static int decode_mb_info(IVI45DecContext *ctx, IVIBandDesc *band,
00438                           IVITile *tile, AVCodecContext *avctx)
00439 {
00440     int         x, y, mv_x, mv_y, mv_delta, offs, mb_offset, blks_per_mb,
00441                 mv_scale, mb_type_bits;
00442     IVIMbInfo   *mb, *ref_mb;
00443     int         row_offset = band->mb_size * band->pitch;
00444 
00445     mb     = tile->mbs;
00446     ref_mb = tile->ref_mbs;
00447     offs   = tile->ypos * band->pitch + tile->xpos;
00448 
00449     blks_per_mb  = band->mb_size   != band->blk_size  ? 4 : 1;
00450     mb_type_bits = ctx->frame_type == FRAMETYPE_BIDIR ? 2 : 1;
00451 
00452     /* scale factor for motion vectors */
00453     mv_scale = (ctx->planes[0].bands[0].mb_size >> 3) - (band->mb_size >> 3);
00454     mv_x = mv_y = 0;
00455 
00456     for (y = tile->ypos; y < tile->ypos + tile->height; y += band->mb_size) {
00457         mb_offset = offs;
00458 
00459         for (x = tile->xpos; x < tile->xpos + tile->width; x += band->mb_size) {
00460             mb->xpos     = x;
00461             mb->ypos     = y;
00462             mb->buf_offs = mb_offset;
00463 
00464             if (get_bits1(&ctx->gb)) {
00465                 if (ctx->frame_type == FRAMETYPE_INTRA) {
00466                     av_log(avctx, AV_LOG_ERROR, "Empty macroblock in an INTRA picture!\n");
00467                     return AVERROR_INVALIDDATA;
00468                 }
00469                 mb->type = 1; /* empty macroblocks are always INTER */
00470                 mb->cbp  = 0; /* all blocks are empty */
00471 
00472                 mb->q_delta = 0;
00473                 if (!band->plane && !band->band_num && ctx->in_q) {
00474                     mb->q_delta = get_vlc2(&ctx->gb, ctx->mb_vlc.tab->table,
00475                                            IVI_VLC_BITS, 1);
00476                     mb->q_delta = IVI_TOSIGNED(mb->q_delta);
00477                 }
00478 
00479                 mb->mv_x = mb->mv_y = 0; /* no motion vector coded */
00480                 if (band->inherit_mv && ref_mb) {
00481                     /* motion vector inheritance */
00482                     if (mv_scale) {
00483                         mb->mv_x = ivi_scale_mv(ref_mb->mv_x, mv_scale);
00484                         mb->mv_y = ivi_scale_mv(ref_mb->mv_y, mv_scale);
00485                     } else {
00486                         mb->mv_x = ref_mb->mv_x;
00487                         mb->mv_y = ref_mb->mv_y;
00488                     }
00489                 }
00490             } else {
00491                 if (band->inherit_mv) {
00492                     /* copy mb_type from corresponding reference mb */
00493                     if (!ref_mb)
00494                         return AVERROR_INVALIDDATA;
00495                     mb->type = ref_mb->type;
00496                 } else if (ctx->frame_type == FRAMETYPE_INTRA) {
00497                     mb->type = 0; /* mb_type is always INTRA for intra-frames */
00498                 } else {
00499                     mb->type = get_bits(&ctx->gb, mb_type_bits);
00500                 }
00501 
00502                 mb->cbp = get_bits(&ctx->gb, blks_per_mb);
00503 
00504                 mb->q_delta = 0;
00505                 if (band->inherit_qdelta) {
00506                     if (ref_mb) mb->q_delta = ref_mb->q_delta;
00507                 } else if (mb->cbp || (!band->plane && !band->band_num &&
00508                            ctx->in_q)) {
00509                     mb->q_delta = get_vlc2(&ctx->gb, ctx->mb_vlc.tab->table,
00510                                            IVI_VLC_BITS, 1);
00511                     mb->q_delta = IVI_TOSIGNED(mb->q_delta);
00512                 }
00513 
00514                 if (!mb->type) {
00515                     mb->mv_x = mb->mv_y = 0; /* there is no motion vector in intra-macroblocks */
00516                 } else {
00517                     if (band->inherit_mv) {
00518                         if (ref_mb)
00519                             /* motion vector inheritance */
00520                             if (mv_scale) {
00521                                 mb->mv_x = ivi_scale_mv(ref_mb->mv_x, mv_scale);
00522                                 mb->mv_y = ivi_scale_mv(ref_mb->mv_y, mv_scale);
00523                             } else {
00524                                 mb->mv_x = ref_mb->mv_x;
00525                                 mb->mv_y = ref_mb->mv_y;
00526                             }
00527                     } else {
00528                         /* decode motion vector deltas */
00529                         mv_delta = get_vlc2(&ctx->gb, ctx->mb_vlc.tab->table,
00530                                             IVI_VLC_BITS, 1);
00531                         mv_y += IVI_TOSIGNED(mv_delta);
00532                         mv_delta = get_vlc2(&ctx->gb, ctx->mb_vlc.tab->table,
00533                                             IVI_VLC_BITS, 1);
00534                         mv_x += IVI_TOSIGNED(mv_delta);
00535                         mb->mv_x = mv_x;
00536                         mb->mv_y = mv_y;
00537                     }
00538                 }
00539             }
00540 
00541             mb++;
00542             if (ref_mb)
00543                 ref_mb++;
00544             mb_offset += band->mb_size;
00545         }
00546 
00547         offs += row_offset;
00548     }
00549 
00550     align_get_bits(&ctx->gb);
00551 
00552     return 0;
00553 }
00554 
00555 
00561 static void switch_buffers(IVI45DecContext *ctx)
00562 {
00563     switch (ctx->prev_frame_type) {
00564     case FRAMETYPE_INTRA:
00565     case FRAMETYPE_INTER:
00566         ctx->buf_switch ^= 1;
00567         ctx->dst_buf     = ctx->buf_switch;
00568         ctx->ref_buf     = ctx->buf_switch ^ 1;
00569         break;
00570     case FRAMETYPE_INTER_NOREF:
00571         break;
00572     }
00573 
00574     switch (ctx->frame_type) {
00575     case FRAMETYPE_INTRA:
00576         ctx->buf_switch = 0;
00577         /* FALLTHROUGH */
00578     case FRAMETYPE_INTER:
00579         ctx->dst_buf = ctx->buf_switch;
00580         ctx->ref_buf = ctx->buf_switch ^ 1;
00581         break;
00582     case FRAMETYPE_INTER_NOREF:
00583     case FRAMETYPE_NULL_FIRST:
00584     case FRAMETYPE_NULL_LAST:
00585         break;
00586     }
00587 }
00588 
00589 
00590 static int is_nonnull_frame(IVI45DecContext *ctx)
00591 {
00592     return ctx->frame_type < FRAMETYPE_NULL_FIRST;
00593 }
00594 
00595 
00596 static av_cold int decode_init(AVCodecContext *avctx)
00597 {
00598     IVI45DecContext *ctx = avctx->priv_data;
00599 
00600     ff_ivi_init_static_vlc();
00601 
00602     /* copy rvmap tables in our context so we can apply changes to them */
00603     memcpy(ctx->rvmap_tabs, ff_ivi_rvmap_tabs, sizeof(ff_ivi_rvmap_tabs));
00604 
00605     /* Force allocation of the internal buffers */
00606     /* during picture header decoding.          */
00607     ctx->pic_conf.pic_width  = 0;
00608     ctx->pic_conf.pic_height = 0;
00609 
00610     avctx->pix_fmt = PIX_FMT_YUV410P;
00611 
00612     ctx->decode_pic_hdr   = decode_pic_hdr;
00613     ctx->decode_band_hdr  = decode_band_hdr;
00614     ctx->decode_mb_info   = decode_mb_info;
00615     ctx->switch_buffers   = switch_buffers;
00616     ctx->is_nonnull_frame = is_nonnull_frame;
00617 
00618     return 0;
00619 }
00620 
00621 
00622 AVCodec ff_indeo4_decoder = {
00623     .name           = "indeo4",
00624     .type           = AVMEDIA_TYPE_VIDEO,
00625     .id             = CODEC_ID_INDEO4,
00626     .priv_data_size = sizeof(IVI45DecContext),
00627     .init           = decode_init,
00628     .close          = ff_ivi_decode_close,
00629     .decode         = ff_ivi_decode_frame,
00630     .long_name      = NULL_IF_CONFIG_SMALL("Intel Indeo Video Interactive 4"),
00631 };