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