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libschroedingerdec.c
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1 /*
2  * Dirac decoder support via Schroedinger libraries
3  * Copyright (c) 2008 BBC, Anuradha Suraparaju <asuraparaju at gmail dot com >
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23 * @file
24 * Dirac decoder support via libschroedinger-1.0 libraries. More details about
25 * the Schroedinger project can be found at http://www.diracvideo.org/.
26 * The library implements Dirac Specification Version 2.2.
27 * (http://dirac.sourceforge.net/specification.html).
28 */
29 
30 #include <string.h>
31 
32 #include "libavutil/imgutils.h"
33 #include "libavutil/internal.h"
34 #include "libavutil/intreadwrite.h"
35 #include "libavutil/mem.h"
36 #include "avcodec.h"
37 #include "internal.h"
38 #include "libschroedinger.h"
39 
40 #include <schroedinger/schro.h>
41 #include <schroedinger/schrodebug.h>
42 #include <schroedinger/schrovideoformat.h>
43 
44 /** SchroFrame and Pts relation */
45 typedef struct LibSchroFrameContext {
46  SchroFrame *frame;
47  int64_t pts;
49 
50 /** libschroedinger decoder private data */
51 typedef struct SchroDecoderParams {
52  /** Schroedinger video format */
53  SchroVideoFormat *format;
54 
55  /** Schroedinger frame format */
56  SchroFrameFormat frame_format;
57 
58  /** decoder handle */
59  SchroDecoder* decoder;
60 
61  /** queue storing decoded frames */
63 
64  /** end of sequence signalled */
66 
67  /** end of sequence pulled */
69 
70  /** decoded picture */
73 
74 typedef struct SchroParseUnitContext {
75  const uint8_t *buf;
76  int buf_size;
78 
79 
80 static void libschroedinger_decode_buffer_free(SchroBuffer *schro_buf,
81  void *priv)
82 {
83  av_freep(&priv);
84 }
85 
87  const uint8_t *buf, int buf_size)
88 {
89  parse_ctx->buf = buf;
90  parse_ctx->buf_size = buf_size;
91 }
92 
93 static SchroBuffer *find_next_parse_unit(SchroParseUnitContext *parse_ctx)
94 {
95  SchroBuffer *enc_buf = NULL;
96  int next_pu_offset = 0;
97  unsigned char *in_buf;
98 
99  if (parse_ctx->buf_size < 13 ||
100  parse_ctx->buf[0] != 'B' ||
101  parse_ctx->buf[1] != 'B' ||
102  parse_ctx->buf[2] != 'C' ||
103  parse_ctx->buf[3] != 'D')
104  return NULL;
105 
106  next_pu_offset = (parse_ctx->buf[5] << 24) +
107  (parse_ctx->buf[6] << 16) +
108  (parse_ctx->buf[7] << 8) +
109  parse_ctx->buf[8];
110 
111  if (next_pu_offset == 0 &&
112  SCHRO_PARSE_CODE_IS_END_OF_SEQUENCE(parse_ctx->buf[4]))
113  next_pu_offset = 13;
114 
115  if (next_pu_offset <= 0 || parse_ctx->buf_size < next_pu_offset)
116  return NULL;
117 
118  in_buf = av_malloc(next_pu_offset);
119  if (!in_buf) {
120  av_log(parse_ctx, AV_LOG_ERROR, "Unable to allocate input buffer\n");
121  return NULL;
122  }
123 
124  memcpy(in_buf, parse_ctx->buf, next_pu_offset);
125  enc_buf = schro_buffer_new_with_data(in_buf, next_pu_offset);
126  enc_buf->free = libschroedinger_decode_buffer_free;
127  enc_buf->priv = in_buf;
128 
129  parse_ctx->buf += next_pu_offset;
130  parse_ctx->buf_size -= next_pu_offset;
131 
132  return enc_buf;
133 }
134 
135 /**
136 * Returns FFmpeg chroma format.
137 */
138 static enum AVPixelFormat get_chroma_format(SchroChromaFormat schro_pix_fmt)
139 {
140  int num_formats = sizeof(schro_pixel_format_map) /
141  sizeof(schro_pixel_format_map[0]);
142  int idx;
143 
144  for (idx = 0; idx < num_formats; ++idx)
145  if (schro_pixel_format_map[idx].schro_pix_fmt == schro_pix_fmt)
146  return schro_pixel_format_map[idx].ff_pix_fmt;
147  return AV_PIX_FMT_NONE;
148 }
149 
151 {
152 
153  SchroDecoderParams *p_schro_params = avccontext->priv_data;
154  /* First of all, initialize our supporting libraries. */
155  schro_init();
156 
157  schro_debug_set_level(avccontext->debug);
158  p_schro_params->decoder = schro_decoder_new();
159  schro_decoder_set_skip_ratio(p_schro_params->decoder, 1);
160 
161  if (!p_schro_params->decoder)
162  return -1;
163 
164  /* Initialize the decoded frame queue. */
165  ff_schro_queue_init(&p_schro_params->dec_frame_queue);
166  return 0;
167 }
168 
170 {
171  schro_frame_unref(frame);
172 }
173 
175 {
176  SchroDecoderParams *p_schro_params = avccontext->priv_data;
177  SchroDecoder *decoder = p_schro_params->decoder;
178 
179  p_schro_params->format = schro_decoder_get_video_format(decoder);
180 
181  /* Tell FFmpeg about sequence details. */
182  if (av_image_check_size(p_schro_params->format->width,
183  p_schro_params->format->height, 0, avccontext) < 0) {
184  av_log(avccontext, AV_LOG_ERROR, "invalid dimensions (%dx%d)\n",
185  p_schro_params->format->width, p_schro_params->format->height);
186  avccontext->height = avccontext->width = 0;
187  return;
188  }
189  avccontext->height = p_schro_params->format->height;
190  avccontext->width = p_schro_params->format->width;
191  avccontext->pix_fmt = get_chroma_format(p_schro_params->format->chroma_format);
192 
193  if (ff_get_schro_frame_format(p_schro_params->format->chroma_format,
194  &p_schro_params->frame_format) == -1) {
195  av_log(avccontext, AV_LOG_ERROR,
196  "This codec currently only supports planar YUV 4:2:0, 4:2:2 "
197  "and 4:4:4 formats.\n");
198  return;
199  }
200 
201  avccontext->time_base.den = p_schro_params->format->frame_rate_numerator;
202  avccontext->time_base.num = p_schro_params->format->frame_rate_denominator;
203 }
204 
206  void *data, int *got_frame,
207  AVPacket *avpkt)
208 {
209  const uint8_t *buf = avpkt->data;
210  int buf_size = avpkt->size;
211  int64_t pts = avpkt->pts;
212  SchroTag *tag;
213 
214  SchroDecoderParams *p_schro_params = avccontext->priv_data;
215  SchroDecoder *decoder = p_schro_params->decoder;
216  SchroBuffer *enc_buf;
217  SchroFrame* frame;
218  int state;
219  int go = 1;
220  int outer = 1;
221  SchroParseUnitContext parse_ctx;
222  LibSchroFrameContext *framewithpts = NULL;
223 
224  *got_frame = 0;
225 
226  parse_context_init(&parse_ctx, buf, buf_size);
227  if (!buf_size) {
228  if (!p_schro_params->eos_signalled) {
229  state = schro_decoder_push_end_of_stream(decoder);
230  p_schro_params->eos_signalled = 1;
231  }
232  }
233 
234  /* Loop through all the individual parse units in the input buffer */
235  do {
236  if ((enc_buf = find_next_parse_unit(&parse_ctx))) {
237  /* Set Schrotag with the pts to be recovered after decoding*/
238  enc_buf->tag = schro_tag_new(av_malloc(sizeof(int64_t)), av_free);
239  if (!enc_buf->tag->value) {
240  av_log(avccontext, AV_LOG_ERROR, "Unable to allocate SchroTag\n");
241  return AVERROR(ENOMEM);
242  }
243  AV_WN(64, enc_buf->tag->value, pts);
244  /* Push buffer into decoder. */
245  if (SCHRO_PARSE_CODE_IS_PICTURE(enc_buf->data[4]) &&
246  SCHRO_PARSE_CODE_NUM_REFS(enc_buf->data[4]) > 0)
247  avccontext->has_b_frames = 1;
248  state = schro_decoder_push(decoder, enc_buf);
249  if (state == SCHRO_DECODER_FIRST_ACCESS_UNIT)
251  go = 1;
252  } else
253  outer = 0;
254 
255  while (go) {
256  /* Parse data and process result. */
257  state = schro_decoder_wait(decoder);
258  switch (state) {
259  case SCHRO_DECODER_FIRST_ACCESS_UNIT:
261  break;
262 
263  case SCHRO_DECODER_NEED_BITS:
264  /* Need more input data - stop iterating over what we have. */
265  go = 0;
266  break;
267 
268  case SCHRO_DECODER_NEED_FRAME:
269  /* Decoder needs a frame - create one and push it in. */
270  frame = ff_create_schro_frame(avccontext,
271  p_schro_params->frame_format);
272  schro_decoder_add_output_picture(decoder, frame);
273  break;
274 
275  case SCHRO_DECODER_OK:
276  /* Pull a frame out of the decoder. */
277  tag = schro_decoder_get_picture_tag(decoder);
278  frame = schro_decoder_pull(decoder);
279 
280  if (frame) {
281  /* Add relation between schroframe and pts. */
282  framewithpts = av_malloc(sizeof(LibSchroFrameContext));
283  if (!framewithpts) {
284  av_log(avccontext, AV_LOG_ERROR, "Unable to allocate FrameWithPts\n");
285  return AVERROR(ENOMEM);
286  }
287  framewithpts->frame = frame;
288  framewithpts->pts = AV_RN64(tag->value);
289  ff_schro_queue_push_back(&p_schro_params->dec_frame_queue,
290  framewithpts);
291  }
292  break;
293  case SCHRO_DECODER_EOS:
294  go = 0;
295  p_schro_params->eos_pulled = 1;
296  schro_decoder_reset(decoder);
297  outer = 0;
298  break;
299 
300  case SCHRO_DECODER_ERROR:
301  return -1;
302  break;
303  }
304  }
305  } while (outer);
306 
307  /* Grab next frame to be returned from the top of the queue. */
308  framewithpts = ff_schro_queue_pop(&p_schro_params->dec_frame_queue);
309 
310  if (framewithpts && framewithpts->frame) {
311  if (p_schro_params->dec_frame.data[0])
312  avccontext->release_buffer(avccontext, &p_schro_params->dec_frame);
313  if (ff_get_buffer(avccontext, &p_schro_params->dec_frame) < 0) {
314  av_log(avccontext, AV_LOG_ERROR, "Unable to allocate buffer\n");
315  return AVERROR(ENOMEM);
316  }
317 
318  memcpy(p_schro_params->dec_frame.data[0],
319  framewithpts->frame->components[0].data,
320  framewithpts->frame->components[0].length);
321 
322  memcpy(p_schro_params->dec_frame.data[1],
323  framewithpts->frame->components[1].data,
324  framewithpts->frame->components[1].length);
325 
326  memcpy(p_schro_params->dec_frame.data[2],
327  framewithpts->frame->components[2].data,
328  framewithpts->frame->components[2].length);
329 
330  /* Fill frame with current buffer data from Schroedinger. */
331  p_schro_params->dec_frame.format = -1; /* Unknown -1 */
332  p_schro_params->dec_frame.width = framewithpts->frame->width;
333  p_schro_params->dec_frame.height = framewithpts->frame->height;
334  p_schro_params->dec_frame.pkt_pts = framewithpts->pts;
335  p_schro_params->dec_frame.linesize[0] = framewithpts->frame->components[0].stride;
336  p_schro_params->dec_frame.linesize[1] = framewithpts->frame->components[1].stride;
337  p_schro_params->dec_frame.linesize[2] = framewithpts->frame->components[2].stride;
338 
339  *(AVFrame*)data = p_schro_params->dec_frame;
340  *got_frame = 1;
341 
342  /* Now free the frame resources. */
344  av_free(framewithpts);
345  } else {
346  data = NULL;
347  *got_frame = 0;
348  }
349  return buf_size;
350 }
351 
352 
354 {
355  SchroDecoderParams *p_schro_params = avccontext->priv_data;
356  /* Free the decoder. */
357  schro_decoder_free(p_schro_params->decoder);
358  av_freep(&p_schro_params->format);
359 
360  if (p_schro_params->dec_frame.data[0])
361  avccontext->release_buffer(avccontext, &p_schro_params->dec_frame);
362 
363  /* Free data in the output frame queue. */
364  ff_schro_queue_free(&p_schro_params->dec_frame_queue,
366 
367  return 0;
368 }
369 
370 static void libschroedinger_flush(AVCodecContext *avccontext)
371 {
372  /* Got a seek request. Free the decoded frames queue and then reset
373  * the decoder */
374  SchroDecoderParams *p_schro_params = avccontext->priv_data;
375 
376  /* Free data in the output frame queue. */
377  ff_schro_queue_free(&p_schro_params->dec_frame_queue,
379 
380  ff_schro_queue_init(&p_schro_params->dec_frame_queue);
381  schro_decoder_reset(p_schro_params->decoder);
382  p_schro_params->eos_pulled = 0;
383  p_schro_params->eos_signalled = 0;
384 }
385 
387  .name = "libschroedinger",
388  .type = AVMEDIA_TYPE_VIDEO,
389  .id = AV_CODEC_ID_DIRAC,
390  .priv_data_size = sizeof(SchroDecoderParams),
394  .capabilities = CODEC_CAP_DELAY,
396  .long_name = NULL_IF_CONFIG_SMALL("libschroedinger Dirac 2.2"),
397 };