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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 FFmpeg.
00006  *
00007  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00028 #include "dirac.h"
00029 #include "avcodec.h"
00030 #include "golomb.h"
00031 #include "mpeg12data.h"
00032 
00033 // defaults for source parameters
00034 static const dirac_source_params dirac_source_parameters_defaults[] = {
00035     { 640,  480,  2, 0, 0, 1,  1, 640,  480,  0, 0, 1, 0 },
00036     { 176,  120,  2, 0, 0, 9,  2, 176,  120,  0, 0, 1, 1 },
00037     { 176,  144,  2, 0, 1, 10, 3, 176,  144,  0, 0, 1, 2 },
00038     { 352,  240,  2, 0, 0, 9,  2, 352,  240,  0, 0, 1, 1 },
00039     { 352,  288,  2, 0, 1, 10, 3, 352,  288,  0, 0, 1, 2 },
00040     { 704,  480,  2, 0, 0, 9,  2, 704,  480,  0, 0, 1, 1 },
00041     { 704,  576,  2, 0, 1, 10, 3, 704,  576,  0, 0, 1, 2 },
00042     { 720,  480,  1, 1, 0, 4,  2, 704,  480,  8, 0, 3, 1 },
00043     { 720,  576,  1, 1, 1, 3,  3, 704,  576,  8, 0, 3, 2 },
00044 
00045     { 1280, 720,  1, 0, 1, 7,  1, 1280, 720,  0, 0, 3, 3 },
00046     { 1280, 720,  1, 0, 1, 6,  1, 1280, 720,  0, 0, 3, 3 },
00047     { 1920, 1080, 1, 1, 1, 4,  1, 1920, 1080, 0, 0, 3, 3 },
00048     { 1920, 1080, 1, 1, 1, 3,  1, 1920, 1080, 0, 0, 3, 3 },
00049     { 1920, 1080, 1, 0, 1, 7,  1, 1920, 1080, 0, 0, 3, 3 },
00050     { 1920, 1080, 1, 0, 1, 6,  1, 1920, 1080, 0, 0, 3, 3 },
00051     { 2048, 1080, 0, 0, 1, 2,  1, 2048, 1080, 0, 0, 4, 4 },
00052     { 4096, 2160, 0, 0, 1, 2,  1, 4096, 2160, 0, 0, 4, 4 },
00053 
00054     { 3840, 2160, 1, 0, 1, 7,  1, 3840, 2160, 0, 0, 3, 3 },
00055     { 3840, 2160, 1, 0, 1, 6,  1, 3840, 2160, 0, 0, 3, 3 },
00056     { 7680, 4320, 1, 0, 1, 7,  1, 3840, 2160, 0, 0, 3, 3 },
00057     { 7680, 4320, 1, 0, 1, 6,  1, 3840, 2160, 0, 0, 3, 3 },
00058 };
00059 
00060 static const AVRational dirac_preset_aspect_ratios[] = {
00061     {1, 1},
00062     {10, 11},
00063     {12, 11},
00064     {40, 33},
00065     {16, 11},
00066     {4, 3},
00067 };
00068 
00069 static const AVRational dirac_frame_rate[] = {
00070     {15000, 1001},
00071     {25, 2},
00072 };
00073 
00074 static const struct {
00075     uint8_t             bitdepth;
00076     enum AVColorRange   color_range;
00077 } pixel_range_presets[] = {
00078     {8,  AVCOL_RANGE_JPEG},
00079     {8,  AVCOL_RANGE_MPEG},
00080     {10, AVCOL_RANGE_MPEG},
00081     {12, AVCOL_RANGE_MPEG},
00082 };
00083 
00084 static const enum AVColorPrimaries dirac_primaries[] = {
00085     AVCOL_PRI_BT709,
00086     AVCOL_PRI_SMPTE170M,
00087     AVCOL_PRI_BT470BG,
00088 };
00089 
00090 static const struct {
00091     enum AVColorPrimaries color_primaries;
00092     enum AVColorSpace colorspace;
00093     enum AVColorTransferCharacteristic color_trc;
00094 } dirac_color_presets[] = {
00095     { AVCOL_PRI_BT709,     AVCOL_SPC_BT709,   AVCOL_TRC_BT709 },
00096     { AVCOL_PRI_SMPTE170M, AVCOL_SPC_BT470BG, AVCOL_TRC_BT709 },
00097     { AVCOL_PRI_BT470BG,   AVCOL_SPC_BT470BG, AVCOL_TRC_BT709 },
00098     { AVCOL_PRI_BT709,     AVCOL_SPC_BT709,   AVCOL_TRC_BT709 },
00099     { AVCOL_PRI_BT709,     AVCOL_SPC_BT709,   AVCOL_TRC_UNSPECIFIED /* DCinema */ },
00100 };
00101 
00102 static const enum PixelFormat dirac_pix_fmt[2][3] = {
00103     { PIX_FMT_YUV444P,  PIX_FMT_YUV422P,  PIX_FMT_YUV420P  },
00104     { PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P, PIX_FMT_YUVJ420P },
00105 };
00106 
00107 static int parse_source_parameters(AVCodecContext *avctx, GetBitContext *gb,
00108                                    dirac_source_params *source)
00109 {
00110     AVRational frame_rate = (AVRational){0,0};
00111     unsigned luma_depth = 8, luma_offset = 16;
00112     int idx;
00113 
00114     if (get_bits1(gb)) {
00115         source->width  = svq3_get_ue_golomb(gb);
00116         source->height = svq3_get_ue_golomb(gb);
00117     }
00118 
00119     // chroma subsampling
00120     if (get_bits1(gb))
00121         source->chroma_format = svq3_get_ue_golomb(gb);
00122     if (source->chroma_format > 2) {
00123         av_log(avctx, AV_LOG_ERROR, "Unknown chroma format %d\n",
00124                source->chroma_format);
00125         return -1;
00126     }
00127 
00128     if (get_bits1(gb))
00129         source->interlaced = svq3_get_ue_golomb(gb);
00130     if (source->interlaced > 1)
00131         return -1;
00132 
00133     // frame rate
00134     if (get_bits1(gb)) {
00135         source->frame_rate_index = svq3_get_ue_golomb(gb);
00136 
00137         if (source->frame_rate_index > 10)
00138             return -1;
00139 
00140         if (!source->frame_rate_index) {
00141             frame_rate.num = svq3_get_ue_golomb(gb);
00142             frame_rate.den = svq3_get_ue_golomb(gb);
00143         }
00144     }
00145     if (source->frame_rate_index > 0) {
00146         if (source->frame_rate_index <= 8)
00147             frame_rate = ff_frame_rate_tab[source->frame_rate_index];
00148         else
00149             frame_rate = dirac_frame_rate[source->frame_rate_index-9];
00150     }
00151     av_reduce(&avctx->time_base.num, &avctx->time_base.den,
00152               frame_rate.den, frame_rate.num, 1<<30);
00153 
00154     // aspect ratio
00155     if (get_bits1(gb)) {
00156         source->aspect_ratio_index = svq3_get_ue_golomb(gb);
00157 
00158         if (source->aspect_ratio_index > 6)
00159             return -1;
00160 
00161         if (!source->aspect_ratio_index) {
00162             avctx->sample_aspect_ratio.num = svq3_get_ue_golomb(gb);
00163             avctx->sample_aspect_ratio.den = svq3_get_ue_golomb(gb);
00164         }
00165     }
00166     if (source->aspect_ratio_index > 0)
00167         avctx->sample_aspect_ratio =
00168                 dirac_preset_aspect_ratios[source->aspect_ratio_index-1];
00169 
00170     if (get_bits1(gb)) {
00171         source->clean_width        = svq3_get_ue_golomb(gb);
00172         source->clean_height       = svq3_get_ue_golomb(gb);
00173         source->clean_left_offset  = svq3_get_ue_golomb(gb);
00174         source->clean_right_offset = svq3_get_ue_golomb(gb);
00175     }
00176 
00177     // Override signal range.
00178     if (get_bits1(gb)) {
00179         source->pixel_range_index = svq3_get_ue_golomb(gb);
00180 
00181         if (source->pixel_range_index > 4)
00182             return -1;
00183 
00184         // This assumes either fullrange or MPEG levels only
00185         if (!source->pixel_range_index) {
00186             luma_offset = svq3_get_ue_golomb(gb);
00187             luma_depth  = av_log2(svq3_get_ue_golomb(gb))+1;
00188             svq3_get_ue_golomb(gb); // chroma offset
00189             svq3_get_ue_golomb(gb); // chroma excursion
00190 
00191             avctx->color_range = luma_offset ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
00192         }
00193     }
00194     if (source->pixel_range_index > 0) {
00195         idx                = source->pixel_range_index-1;
00196         luma_depth         = pixel_range_presets[idx].bitdepth;
00197         avctx->color_range = pixel_range_presets[idx].color_range;
00198     }
00199 
00200     if (luma_depth > 8)
00201         av_log(avctx, AV_LOG_WARNING, "Bitdepth greater than 8");
00202 
00203     avctx->pix_fmt = dirac_pix_fmt[!luma_offset][source->chroma_format];
00204 
00205     // color spec
00206     if (get_bits1(gb)) {
00207         idx = source->color_spec_index = svq3_get_ue_golomb(gb);
00208 
00209         if (source->color_spec_index > 4)
00210             return -1;
00211 
00212         avctx->color_primaries = dirac_color_presets[idx].color_primaries;
00213         avctx->colorspace      = dirac_color_presets[idx].colorspace;
00214         avctx->color_trc       = dirac_color_presets[idx].color_trc;
00215 
00216         if (!source->color_spec_index) {
00217             if (get_bits1(gb)) {
00218                 idx = svq3_get_ue_golomb(gb);
00219                 if (idx < 3)
00220                     avctx->color_primaries = dirac_primaries[idx];
00221             }
00222 
00223             if (get_bits1(gb)) {
00224                 idx = svq3_get_ue_golomb(gb);
00225                 if (!idx)
00226                     avctx->colorspace = AVCOL_SPC_BT709;
00227                 else if (idx == 1)
00228                     avctx->colorspace = AVCOL_SPC_BT470BG;
00229             }
00230 
00231             if (get_bits1(gb) && !svq3_get_ue_golomb(gb))
00232                 avctx->color_trc = AVCOL_TRC_BT709;
00233         }
00234     } else {
00235         idx = source->color_spec_index;
00236         avctx->color_primaries = dirac_color_presets[idx].color_primaries;
00237         avctx->colorspace      = dirac_color_presets[idx].colorspace;
00238         avctx->color_trc       = dirac_color_presets[idx].color_trc;
00239     }
00240 
00241     return 0;
00242 }
00243 
00244 int ff_dirac_parse_sequence_header(AVCodecContext *avctx, GetBitContext *gb,
00245                                    dirac_source_params *source)
00246 {
00247     unsigned version_major, version_minor;
00248     unsigned video_format, picture_coding_mode;
00249 
00250     version_major  = svq3_get_ue_golomb(gb);
00251     version_minor  = svq3_get_ue_golomb(gb);
00252     avctx->profile = svq3_get_ue_golomb(gb);
00253     avctx->level   = svq3_get_ue_golomb(gb);
00254     video_format   = svq3_get_ue_golomb(gb);
00255 
00256     if (version_major < 2)
00257         av_log(avctx, AV_LOG_WARNING, "Stream is old and may not work\n");
00258     else if (version_major > 2)
00259         av_log(avctx, AV_LOG_WARNING, "Stream may have unhandled features\n");
00260 
00261     if (video_format > 20)
00262         return -1;
00263 
00264     // Fill in defaults for the source parameters.
00265     *source = dirac_source_parameters_defaults[video_format];
00266 
00267     // Override the defaults.
00268     if (parse_source_parameters(avctx, gb, source))
00269         return -1;
00270 
00271     if (avcodec_check_dimensions(avctx, source->width, source->height))
00272         return -1;
00273 
00274     avcodec_set_dimensions(avctx, source->width, source->height);
00275 
00276     // currently only used to signal field coding
00277     picture_coding_mode = svq3_get_ue_golomb(gb);
00278     if (picture_coding_mode != 0) {
00279         av_log(avctx, AV_LOG_ERROR, "Unsupported picture coding mode %d",
00280                picture_coding_mode);
00281         return -1;
00282     }
00283     return 0;
00284 }

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