FFmpeg: libavcodec/dirac.c Source File

FFmpeg
dirac.c
Go to the documentation of this file.
1 /*
2  * Copyright (C) 2007 Marco Gerards <marco@gnu.org>
3  * Copyright (C) 2009 David Conrad
4  * Copyright (C) 2011 Jordi Ortiz
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * Dirac Decoder
26  * @author Marco Gerards <marco@gnu.org>, David Conrad, Jordi Ortiz <nenjordi@gmail.com>
27  */
28 
29 #include "libavutil/imgutils.h"
30 #include "dirac.h"
31 #include "avcodec.h"
32 #include "golomb.h"
33 #include "mpeg12data.h"
34 
35 /* defaults for source parameters */
36  static const dirac_source_params dirac_source_parameters_defaults[] = {
37  { 640, 480, 2, 0, 0, 1, 1, 640, 480, 0, 0, 1, 0 },
38  { 176, 120, 2, 0, 0, 9, 2, 176, 120, 0, 0, 1, 1 },
39  { 176, 144, 2, 0, 1, 10, 3, 176, 144, 0, 0, 1, 2 },
40  { 352, 240, 2, 0, 0, 9, 2, 352, 240, 0, 0, 1, 1 },
41  { 352, 288, 2, 0, 1, 10, 3, 352, 288, 0, 0, 1, 2 },
42  { 704, 480, 2, 0, 0, 9, 2, 704, 480, 0, 0, 1, 1 },
43  { 704, 576, 2, 0, 1, 10, 3, 704, 576, 0, 0, 1, 2 },
44  { 720, 480, 1, 1, 0, 4, 2, 704, 480, 8, 0, 3, 1 },
45  { 720, 576, 1, 1, 1, 3, 3, 704, 576, 8, 0, 3, 2 },
46  { 1280, 720, 1, 0, 1, 7, 1, 1280, 720, 0, 0, 3, 3 },
47  { 1280, 720, 1, 0, 1, 6, 1, 1280, 720, 0, 0, 3, 3 },
48  { 1920, 1080, 1, 1, 1, 4, 1, 1920, 1080, 0, 0, 3, 3 },
49  { 1920, 1080, 1, 1, 1, 3, 1, 1920, 1080, 0, 0, 3, 3 },
50  { 1920, 1080, 1, 0, 1, 7, 1, 1920, 1080, 0, 0, 3, 3 },
51  { 1920, 1080, 1, 0, 1, 6, 1, 1920, 1080, 0, 0, 3, 3 },
52  { 2048, 1080, 0, 0, 1, 2, 1, 2048, 1080, 0, 0, 4, 4 },
53  { 4096, 2160, 0, 0, 1, 2, 1, 4096, 2160, 0, 0, 4, 4 },
54  { 3840, 2160, 1, 0, 1, 7, 1, 3840, 2160, 0, 0, 3, 3 },
55  { 3840, 2160, 1, 0, 1, 6, 1, 3840, 2160, 0, 0, 3, 3 },
56  { 7680, 4320, 1, 0, 1, 7, 1, 3840, 2160, 0, 0, 3, 3 },
57  { 7680, 4320, 1, 0, 1, 6, 1, 3840, 2160, 0, 0, 3, 3 },
58 };
59 
60 /* [DIRAC_STD] Table 10.4 - Available preset pixel aspect ratio values */
61  static const AVRational dirac_preset_aspect_ratios[] = {
62  {1, 1},
63  {10, 11},
64  {12, 11},
65  {40, 33},
66  {16, 11},
67  {4, 3},
68 };
69 
70 /* [DIRAC_STD] Values 9,10 of 10.3.5 Frame Rate.
71  * Table 10.3 Available preset frame rate values
72  */
73  static const AVRational dirac_frame_rate[] = {
74  {15000, 1001},
75  {25, 2},
76 };
77 
78 /* [DIRAC_STD] This should be equivalent to Table 10.5 Available signal
79  * range presets */
80 static const struct {
81   uint8_t bitdepth;
82   enum AVColorRange color_range;
83 } pixel_range_presets[] = {
84  {8, AVCOL_RANGE_JPEG},
85  {8, AVCOL_RANGE_MPEG},
86  {10, AVCOL_RANGE_MPEG},
87  {12, AVCOL_RANGE_MPEG},
88 };
89 
90  static const enum AVColorPrimaries dirac_primaries[] = {
91  AVCOL_PRI_BT709,
92  AVCOL_PRI_SMPTE170M,
93  AVCOL_PRI_BT470BG,
94 };
95 
96 static const struct {
97   enum AVColorPrimaries color_primaries;
98   enum AVColorSpace colorspace;
99   enum AVColorTransferCharacteristic color_trc;
100 } dirac_color_presets[] = {
101  { AVCOL_PRI_BT709, AVCOL_SPC_BT709, AVCOL_TRC_BT709 },
102  { AVCOL_PRI_SMPTE170M, AVCOL_SPC_BT470BG, AVCOL_TRC_BT709 },
103  { AVCOL_PRI_BT470BG, AVCOL_SPC_BT470BG, AVCOL_TRC_BT709 },
104  { AVCOL_PRI_BT709, AVCOL_SPC_BT709, AVCOL_TRC_BT709 },
105  { AVCOL_PRI_BT709, AVCOL_SPC_BT709, AVCOL_TRC_UNSPECIFIED /* DCinema */ },
106 };
107 
108 /* [DIRAC_STD] Table 10.2 Supported chroma sampling formats + luma Offset */
109  static const enum AVPixelFormat dirac_pix_fmt[2][3] = {
110  { AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV420P },
111  { AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P },
112 };
113 
114 /* [DIRAC_STD] 10.3 Parse Source Parameters.
115  * source_parameters(base_video_format) */
116  static int parse_source_parameters(AVCodecContext *avctx, GetBitContext *gb,
117  dirac_source_params *source)
118 {
119  AVRational frame_rate = {0,0};
120  unsigned luma_depth = 8, luma_offset = 16;
121  int idx;
122  int chroma_x_shift, chroma_y_shift;
123 
124  /* [DIRAC_STD] 10.3.2 Frame size. frame_size(video_params) */
125  /* [DIRAC_STD] custom_dimensions_flag */
126  if (get_bits1(gb)) {
127  source->width = svq3_get_ue_golomb(gb); /* [DIRAC_STD] FRAME_WIDTH */
128  source->height = svq3_get_ue_golomb(gb); /* [DIRAC_STD] FRAME_HEIGHT */
129  }
130 
131  /* [DIRAC_STD] 10.3.3 Chroma Sampling Format.
132  * chroma_sampling_format(video_params) */
133  /* [DIRAC_STD] custom_chroma_format_flag */
134  if (get_bits1(gb))
135  /* [DIRAC_STD] CHROMA_FORMAT_INDEX */
136  source->chroma_format = svq3_get_ue_golomb(gb);
137  if (source->chroma_format > 2U) {
138  av_log(avctx, AV_LOG_ERROR, "Unknown chroma format %d\n",
139  source->chroma_format);
140  return AVERROR_INVALIDDATA;
141  }
142 
143  /* [DIRAC_STD] 10.3.4 Scan Format. scan_format(video_params) */
144  /* [DIRAC_STD] custom_scan_format_flag */
145  if (get_bits1(gb))
146  /* [DIRAC_STD] SOURCE_SAMPLING */
147  source->interlaced = svq3_get_ue_golomb(gb);
148  if (source->interlaced > 1U)
149  return AVERROR_INVALIDDATA;
150 
151  /* [DIRAC_STD] 10.3.5 Frame Rate. frame_rate(video_params) */
152  if (get_bits1(gb)) { /* [DIRAC_STD] custom_frame_rate_flag */
153  source->frame_rate_index = svq3_get_ue_golomb(gb);
154 
155  if (source->frame_rate_index > 10U)
156  return AVERROR_INVALIDDATA;
157 
158  if (!source->frame_rate_index) {
159  /* [DIRAC_STD] FRAME_RATE_NUMER */
160  frame_rate.num = svq3_get_ue_golomb(gb);
161  /* [DIRAC_STD] FRAME_RATE_DENOM */
162  frame_rate.den = svq3_get_ue_golomb(gb);
163  }
164  }
165  /* [DIRAC_STD] preset_frame_rate(video_params, index) */
166  if (source->frame_rate_index > 0) {
167  if (source->frame_rate_index <= 8)
168  frame_rate = ff_mpeg12_frame_rate_tab[source->frame_rate_index];
169  else
170  /* [DIRAC_STD] Table 10.3 values 9-10 */
171  frame_rate = dirac_frame_rate[source->frame_rate_index-9];
172  }
173  av_reduce(&avctx->time_base.num, &avctx->time_base.den,
174  frame_rate.den, frame_rate.num, 1<<30);
175 
176  /* [DIRAC_STD] 10.3.6 Pixel Aspect Ratio.
177  * pixel_aspect_ratio(video_params) */
178  if (get_bits1(gb)) { /* [DIRAC_STD] custom_pixel_aspect_ratio_flag */
179  /* [DIRAC_STD] index */
180  source->aspect_ratio_index = svq3_get_ue_golomb(gb);
181 
182  if (source->aspect_ratio_index > 6U)
183  return AVERROR_INVALIDDATA;
184 
185  if (!source->aspect_ratio_index) {
186  avctx->sample_aspect_ratio.num = svq3_get_ue_golomb(gb);
187  avctx->sample_aspect_ratio.den = svq3_get_ue_golomb(gb);
188  }
189  }
190  /* [DIRAC_STD] Take value from Table 10.4 Available preset pixel
191  * aspect ratio values */
192  if (source->aspect_ratio_index > 0)
193  avctx->sample_aspect_ratio =
194  dirac_preset_aspect_ratios[source->aspect_ratio_index-1];
195 
196  /* [DIRAC_STD] 10.3.7 Clean area. clean_area(video_params) */
197  if (get_bits1(gb)) { /* [DIRAC_STD] custom_clean_area_flag */
198  /* [DIRAC_STD] CLEAN_WIDTH */
199  source->clean_width = svq3_get_ue_golomb(gb);
200  /* [DIRAC_STD] CLEAN_HEIGHT */
201  source->clean_height = svq3_get_ue_golomb(gb);
202  /* [DIRAC_STD] CLEAN_LEFT_OFFSET */
203  source->clean_left_offset = svq3_get_ue_golomb(gb);
204  /* [DIRAC_STD] CLEAN_RIGHT_OFFSET */
205  source->clean_right_offset = svq3_get_ue_golomb(gb);
206  }
207 
208  /* [DIRAC_STD] 10.3.8 Signal range. signal_range(video_params)
209  * WARNING: Some adaptation seems to be done using the
210  * AVCOL_RANGE_MPEG/JPEG values */
211  if (get_bits1(gb)) { /* [DIRAC_STD] custom_signal_range_flag */
212  /* [DIRAC_STD] index */
213  source->pixel_range_index = svq3_get_ue_golomb(gb);
214 
215  if (source->pixel_range_index > 4U)
216  return AVERROR_INVALIDDATA;
217 
218  /* This assumes either fullrange or MPEG levels only */
219  if (!source->pixel_range_index) {
220  luma_offset = svq3_get_ue_golomb(gb);
221  luma_depth = av_log2(svq3_get_ue_golomb(gb))+1;
222  svq3_get_ue_golomb(gb); /* chroma offset */
223  svq3_get_ue_golomb(gb); /* chroma excursion */
224  avctx->color_range = luma_offset ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
225  }
226  }
227  /* [DIRAC_STD] Table 10.5
228  * Available signal range presets <--> pixel_range_presets */
229  if (source->pixel_range_index > 0) {
230  idx = source->pixel_range_index-1;
231  luma_depth = pixel_range_presets[idx].bitdepth;
232  avctx->color_range = pixel_range_presets[idx].color_range;
233  }
234 
235  if (luma_depth > 8)
236  av_log(avctx, AV_LOG_WARNING, "Bitdepth greater than 8\n");
237 
238  avctx->pix_fmt = dirac_pix_fmt[!luma_offset][source->chroma_format];
239  avcodec_get_chroma_sub_sample(avctx->pix_fmt, &chroma_x_shift, &chroma_y_shift);
240  if ((source->width % (1<<chroma_x_shift)) || (source->height % (1<<chroma_y_shift))) {
241  av_log(avctx, AV_LOG_ERROR, "Dimensions must be a integer multiply of the chroma subsampling\n");
242  return AVERROR_INVALIDDATA;
243  }
244 
245 
246  /* [DIRAC_STD] 10.3.9 Colour specification. colour_spec(video_params) */
247  if (get_bits1(gb)) { /* [DIRAC_STD] custom_colour_spec_flag */
248  /* [DIRAC_STD] index */
249  idx = source->color_spec_index = svq3_get_ue_golomb(gb);
250 
251  if (source->color_spec_index > 4U)
252  return AVERROR_INVALIDDATA;
253 
254  avctx->color_primaries = dirac_color_presets[idx].color_primaries;
255  avctx->colorspace = dirac_color_presets[idx].colorspace;
256  avctx->color_trc = dirac_color_presets[idx].color_trc;
257 
258  if (!source->color_spec_index) {
259  /* [DIRAC_STD] 10.3.9.1 Colour primaries */
260  if (get_bits1(gb)) {
261  idx = svq3_get_ue_golomb(gb);
262  if (idx < 3U)
263  avctx->color_primaries = dirac_primaries[idx];
264  }
265  /* [DIRAC_STD] 10.3.9.2 Colour matrix */
266  if (get_bits1(gb)) {
267  idx = svq3_get_ue_golomb(gb);
268  if (!idx)
269  avctx->colorspace = AVCOL_SPC_BT709;
270  else if (idx == 1)
271  avctx->colorspace = AVCOL_SPC_BT470BG;
272  }
273  /* [DIRAC_STD] 10.3.9.3 Transfer function */
274  if (get_bits1(gb) && !svq3_get_ue_golomb(gb))
275  avctx->color_trc = AVCOL_TRC_BT709;
276  }
277  } else {
278  idx = source->color_spec_index;
279  avctx->color_primaries = dirac_color_presets[idx].color_primaries;
280  avctx->colorspace = dirac_color_presets[idx].colorspace;
281  avctx->color_trc = dirac_color_presets[idx].color_trc;
282  }
283 
284  return 0;
285 }
286 
287 /* [DIRAC_STD] 10. Sequence Header. sequence_header() */
288  int avpriv_dirac_parse_sequence_header(AVCodecContext *avctx, GetBitContext *gb,
289  dirac_source_params *source)
290 {
291  unsigned version_major;
292  unsigned video_format, picture_coding_mode;
293  int ret;
294 
295  /* [DIRAC_SPEC] 10.1 Parse Parameters. parse_parameters() */
296  version_major = svq3_get_ue_golomb(gb);
297  svq3_get_ue_golomb(gb); /* version_minor */
298  avctx->profile = svq3_get_ue_golomb(gb);
299  avctx->level = svq3_get_ue_golomb(gb);
300  /* [DIRAC_SPEC] sequence_header() -> base_video_format as defined in
301  * 10.2 Base Video Format, table 10.1 Dirac predefined video formats */
302  video_format = svq3_get_ue_golomb(gb);
303 
304  if (version_major < 2)
305  av_log(avctx, AV_LOG_WARNING, "Stream is old and may not work\n");
306  else if (version_major > 2)
307  av_log(avctx, AV_LOG_WARNING, "Stream may have unhandled features\n");
308 
309  if (video_format > 20U)
310  return AVERROR_INVALIDDATA;
311 
312  /* Fill in defaults for the source parameters. */
313  *source = dirac_source_parameters_defaults[video_format];
314 
315  /* [DIRAC_STD] 10.3 Source Parameters
316  * Override the defaults. */
317  if (ret = parse_source_parameters(avctx, gb, source))
318  return ret;
319 
320  if (ret = av_image_check_size(source->width, source->height, 0, avctx))
321  return ret;
322 
323  avcodec_set_dimensions(avctx, source->width, source->height);
324 
325  /* [DIRAC_STD] picture_coding_mode shall be 0 for fields and 1 for frames
326  * currently only used to signal field coding */
327  picture_coding_mode = svq3_get_ue_golomb(gb);
328  if (picture_coding_mode != 0) {
329  av_log(avctx, AV_LOG_ERROR, "Unsupported picture coding mode %d\n",
330  picture_coding_mode);
331  return AVERROR_INVALIDDATA;
332  }
333  return 0;
334 }
Generated on Sat May 25 2013 03:58:32 for FFmpeg by   doxygen 1.8.2

AltStyle によって変換されたページ (->オリジナル) /