Libav 0.7.1
libavcodec/dirac.c
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00001 /*
00002  * Copyright (C) 2007 Marco Gerards <marco@gnu.org>
00003  * Copyright (C) 2009 David Conrad
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 
00028 #include "libavutil/imgutils.h"
00029 #include "dirac.h"
00030 #include "avcodec.h"
00031 #include "golomb.h"
00032 #include "mpeg12data.h"
00033 
00034 // defaults for source parameters
00035 static const dirac_source_params dirac_source_parameters_defaults[] = {
00036     { 640,  480,  2, 0, 0, 1,  1, 640,  480,  0, 0, 1, 0 },
00037     { 176,  120,  2, 0, 0, 9,  2, 176,  120,  0, 0, 1, 1 },
00038     { 176,  144,  2, 0, 1, 10, 3, 176,  144,  0, 0, 1, 2 },
00039     { 352,  240,  2, 0, 0, 9,  2, 352,  240,  0, 0, 1, 1 },
00040     { 352,  288,  2, 0, 1, 10, 3, 352,  288,  0, 0, 1, 2 },
00041     { 704,  480,  2, 0, 0, 9,  2, 704,  480,  0, 0, 1, 1 },
00042     { 704,  576,  2, 0, 1, 10, 3, 704,  576,  0, 0, 1, 2 },
00043     { 720,  480,  1, 1, 0, 4,  2, 704,  480,  8, 0, 3, 1 },
00044     { 720,  576,  1, 1, 1, 3,  3, 704,  576,  8, 0, 3, 2 },
00045 
00046     { 1280, 720,  1, 0, 1, 7,  1, 1280, 720,  0, 0, 3, 3 },
00047     { 1280, 720,  1, 0, 1, 6,  1, 1280, 720,  0, 0, 3, 3 },
00048     { 1920, 1080, 1, 1, 1, 4,  1, 1920, 1080, 0, 0, 3, 3 },
00049     { 1920, 1080, 1, 1, 1, 3,  1, 1920, 1080, 0, 0, 3, 3 },
00050     { 1920, 1080, 1, 0, 1, 7,  1, 1920, 1080, 0, 0, 3, 3 },
00051     { 1920, 1080, 1, 0, 1, 6,  1, 1920, 1080, 0, 0, 3, 3 },
00052     { 2048, 1080, 0, 0, 1, 2,  1, 2048, 1080, 0, 0, 4, 4 },
00053     { 4096, 2160, 0, 0, 1, 2,  1, 4096, 2160, 0, 0, 4, 4 },
00054 
00055     { 3840, 2160, 1, 0, 1, 7,  1, 3840, 2160, 0, 0, 3, 3 },
00056     { 3840, 2160, 1, 0, 1, 6,  1, 3840, 2160, 0, 0, 3, 3 },
00057     { 7680, 4320, 1, 0, 1, 7,  1, 3840, 2160, 0, 0, 3, 3 },
00058     { 7680, 4320, 1, 0, 1, 6,  1, 3840, 2160, 0, 0, 3, 3 },
00059 };
00060 
00061 static const AVRational dirac_preset_aspect_ratios[] = {
00062     {1, 1},
00063     {10, 11},
00064     {12, 11},
00065     {40, 33},
00066     {16, 11},
00067     {4, 3},
00068 };
00069 
00070 static const AVRational dirac_frame_rate[] = {
00071     {15000, 1001},
00072     {25, 2},
00073 };
00074 
00075 static const struct {
00076     uint8_t             bitdepth;
00077     enum AVColorRange   color_range;
00078 } pixel_range_presets[] = {
00079     {8,  AVCOL_RANGE_JPEG},
00080     {8,  AVCOL_RANGE_MPEG},
00081     {10, AVCOL_RANGE_MPEG},
00082     {12, AVCOL_RANGE_MPEG},
00083 };
00084 
00085 static const enum AVColorPrimaries dirac_primaries[] = {
00086     AVCOL_PRI_BT709,
00087     AVCOL_PRI_SMPTE170M,
00088     AVCOL_PRI_BT470BG,
00089 };
00090 
00091 static const struct {
00092     enum AVColorPrimaries color_primaries;
00093     enum AVColorSpace colorspace;
00094     enum AVColorTransferCharacteristic color_trc;
00095 } dirac_color_presets[] = {
00096     { AVCOL_PRI_BT709,     AVCOL_SPC_BT709,   AVCOL_TRC_BT709 },
00097     { AVCOL_PRI_SMPTE170M, AVCOL_SPC_BT470BG, AVCOL_TRC_BT709 },
00098     { AVCOL_PRI_BT470BG,   AVCOL_SPC_BT470BG, AVCOL_TRC_BT709 },
00099     { AVCOL_PRI_BT709,     AVCOL_SPC_BT709,   AVCOL_TRC_BT709 },
00100     { AVCOL_PRI_BT709,     AVCOL_SPC_BT709,   AVCOL_TRC_UNSPECIFIED /* DCinema */ },
00101 };
00102 
00103 static const enum PixelFormat dirac_pix_fmt[2][3] = {
00104     { PIX_FMT_YUV444P,  PIX_FMT_YUV422P,  PIX_FMT_YUV420P  },
00105     { PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P, PIX_FMT_YUVJ420P },
00106 };
00107 
00108 static int parse_source_parameters(AVCodecContext *avctx, GetBitContext *gb,
00109                                    dirac_source_params *source)
00110 {
00111     AVRational frame_rate = (AVRational){0,0};
00112     unsigned luma_depth = 8, luma_offset = 16;
00113     int idx;
00114 
00115     if (get_bits1(gb)) {
00116         source->width  = svq3_get_ue_golomb(gb);
00117         source->height = svq3_get_ue_golomb(gb);
00118     }
00119 
00120     // chroma subsampling
00121     if (get_bits1(gb))
00122         source->chroma_format = svq3_get_ue_golomb(gb);
00123     if (source->chroma_format > 2) {
00124         av_log(avctx, AV_LOG_ERROR, "Unknown chroma format %d\n",
00125                source->chroma_format);
00126         return -1;
00127     }
00128 
00129     if (get_bits1(gb))
00130         source->interlaced = svq3_get_ue_golomb(gb);
00131     if (source->interlaced > 1)
00132         return -1;
00133 
00134     // frame rate
00135     if (get_bits1(gb)) {
00136         source->frame_rate_index = svq3_get_ue_golomb(gb);
00137 
00138         if (source->frame_rate_index > 10)
00139             return -1;
00140 
00141         if (!source->frame_rate_index) {
00142             frame_rate.num = svq3_get_ue_golomb(gb);
00143             frame_rate.den = svq3_get_ue_golomb(gb);
00144         }
00145     }
00146     if (source->frame_rate_index > 0) {
00147         if (source->frame_rate_index <= 8)
00148             frame_rate = ff_frame_rate_tab[source->frame_rate_index];
00149         else
00150             frame_rate = dirac_frame_rate[source->frame_rate_index-9];
00151     }
00152     av_reduce(&avctx->time_base.num, &avctx->time_base.den,
00153               frame_rate.den, frame_rate.num, 1<<30);
00154 
00155     // aspect ratio
00156     if (get_bits1(gb)) {
00157         source->aspect_ratio_index = svq3_get_ue_golomb(gb);
00158 
00159         if (source->aspect_ratio_index > 6)
00160             return -1;
00161 
00162         if (!source->aspect_ratio_index) {
00163             avctx->sample_aspect_ratio.num = svq3_get_ue_golomb(gb);
00164             avctx->sample_aspect_ratio.den = svq3_get_ue_golomb(gb);
00165         }
00166     }
00167     if (source->aspect_ratio_index > 0)
00168         avctx->sample_aspect_ratio =
00169                 dirac_preset_aspect_ratios[source->aspect_ratio_index-1];
00170 
00171     if (get_bits1(gb)) {
00172         source->clean_width        = svq3_get_ue_golomb(gb);
00173         source->clean_height       = svq3_get_ue_golomb(gb);
00174         source->clean_left_offset  = svq3_get_ue_golomb(gb);
00175         source->clean_right_offset = svq3_get_ue_golomb(gb);
00176     }
00177 
00178     // Override signal range.
00179     if (get_bits1(gb)) {
00180         source->pixel_range_index = svq3_get_ue_golomb(gb);
00181 
00182         if (source->pixel_range_index > 4)
00183             return -1;
00184 
00185         // This assumes either fullrange or MPEG levels only
00186         if (!source->pixel_range_index) {
00187             luma_offset = svq3_get_ue_golomb(gb);
00188             luma_depth  = av_log2(svq3_get_ue_golomb(gb))+1;
00189             svq3_get_ue_golomb(gb); // chroma offset
00190             svq3_get_ue_golomb(gb); // chroma excursion
00191 
00192             avctx->color_range = luma_offset ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
00193         }
00194     }
00195     if (source->pixel_range_index > 0) {
00196         idx                = source->pixel_range_index-1;
00197         luma_depth         = pixel_range_presets[idx].bitdepth;
00198         avctx->color_range = pixel_range_presets[idx].color_range;
00199     }
00200 
00201     if (luma_depth > 8)
00202         av_log(avctx, AV_LOG_WARNING, "Bitdepth greater than 8");
00203 
00204     avctx->pix_fmt = dirac_pix_fmt[!luma_offset][source->chroma_format];
00205 
00206     // color spec
00207     if (get_bits1(gb)) {
00208         idx = source->color_spec_index = svq3_get_ue_golomb(gb);
00209 
00210         if (source->color_spec_index > 4)
00211             return -1;
00212 
00213         avctx->color_primaries = dirac_color_presets[idx].color_primaries;
00214         avctx->colorspace      = dirac_color_presets[idx].colorspace;
00215         avctx->color_trc       = dirac_color_presets[idx].color_trc;
00216 
00217         if (!source->color_spec_index) {
00218             if (get_bits1(gb)) {
00219                 idx = svq3_get_ue_golomb(gb);
00220                 if (idx < 3)
00221                     avctx->color_primaries = dirac_primaries[idx];
00222             }
00223 
00224             if (get_bits1(gb)) {
00225                 idx = svq3_get_ue_golomb(gb);
00226                 if (!idx)
00227                     avctx->colorspace = AVCOL_SPC_BT709;
00228                 else if (idx == 1)
00229                     avctx->colorspace = AVCOL_SPC_BT470BG;
00230             }
00231 
00232             if (get_bits1(gb) && !svq3_get_ue_golomb(gb))
00233                 avctx->color_trc = AVCOL_TRC_BT709;
00234         }
00235     } else {
00236         idx = source->color_spec_index;
00237         avctx->color_primaries = dirac_color_presets[idx].color_primaries;
00238         avctx->colorspace      = dirac_color_presets[idx].colorspace;
00239         avctx->color_trc       = dirac_color_presets[idx].color_trc;
00240     }
00241 
00242     return 0;
00243 }
00244 
00245 int ff_dirac_parse_sequence_header(AVCodecContext *avctx, GetBitContext *gb,
00246                                    dirac_source_params *source)
00247 {
00248     unsigned version_major;
00249     unsigned video_format, picture_coding_mode;
00250 
00251     version_major  = svq3_get_ue_golomb(gb);
00252     svq3_get_ue_golomb(gb); /* version_minor */
00253     avctx->profile = svq3_get_ue_golomb(gb);
00254     avctx->level   = svq3_get_ue_golomb(gb);
00255     video_format   = svq3_get_ue_golomb(gb);
00256 
00257     if (version_major < 2)
00258         av_log(avctx, AV_LOG_WARNING, "Stream is old and may not work\n");
00259     else if (version_major > 2)
00260         av_log(avctx, AV_LOG_WARNING, "Stream may have unhandled features\n");
00261 
00262     if (video_format > 20)
00263         return -1;
00264 
00265     // Fill in defaults for the source parameters.
00266     *source = dirac_source_parameters_defaults[video_format];
00267 
00268     // Override the defaults.
00269     if (parse_source_parameters(avctx, gb, source))
00270         return -1;
00271 
00272     if (av_image_check_size(source->width, source->height, 0, avctx))
00273         return -1;
00274 
00275     avcodec_set_dimensions(avctx, source->width, source->height);
00276 
00277     // currently only used to signal field coding
00278     picture_coding_mode = svq3_get_ue_golomb(gb);
00279     if (picture_coding_mode != 0) {
00280         av_log(avctx, AV_LOG_ERROR, "Unsupported picture coding mode %d",
00281                picture_coding_mode);
00282         return -1;
00283     }
00284     return 0;
00285 }