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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 */
70 
71 typedef struct SchroParseUnitContext {
72  const uint8_t *buf;
73  int buf_size;
75 
76 
77 static void libschroedinger_decode_buffer_free(SchroBuffer *schro_buf,
78  void *priv)
79 {
80  av_freep(&priv);
81 }
82 
84  const uint8_t *buf, int buf_size)
85 {
86  parse_ctx->buf = buf;
87  parse_ctx->buf_size = buf_size;
88 }
89 
90 static SchroBuffer *find_next_parse_unit(SchroParseUnitContext *parse_ctx)
91 {
92  SchroBuffer *enc_buf = NULL;
93  int next_pu_offset = 0;
94  unsigned char *in_buf;
95 
96  if (parse_ctx->buf_size < 13 ||
97  parse_ctx->buf[0] != 'B' ||
98  parse_ctx->buf[1] != 'B' ||
99  parse_ctx->buf[2] != 'C' ||
100  parse_ctx->buf[3] != 'D')
101  return NULL;
102 
103  next_pu_offset = (parse_ctx->buf[5] << 24) +
104  (parse_ctx->buf[6] << 16) +
105  (parse_ctx->buf[7] << 8) +
106  parse_ctx->buf[8];
107 
108  if (next_pu_offset == 0 &&
109  SCHRO_PARSE_CODE_IS_END_OF_SEQUENCE(parse_ctx->buf[4]))
110  next_pu_offset = 13;
111 
112  if (next_pu_offset <= 0 || parse_ctx->buf_size < next_pu_offset)
113  return NULL;
114 
115  in_buf = av_malloc(next_pu_offset);
116  if (!in_buf) {
117  av_log(parse_ctx, AV_LOG_ERROR, "Unable to allocate input buffer\n");
118  return NULL;
119  }
120 
121  memcpy(in_buf, parse_ctx->buf, next_pu_offset);
122  enc_buf = schro_buffer_new_with_data(in_buf, next_pu_offset);
123  enc_buf->free = libschroedinger_decode_buffer_free;
124  enc_buf->priv = in_buf;
125 
126  parse_ctx->buf += next_pu_offset;
127  parse_ctx->buf_size -= next_pu_offset;
128 
129  return enc_buf;
130 }
131 
132 /**
133 * Returns FFmpeg chroma format.
134 */
135 static enum AVPixelFormat get_chroma_format(SchroChromaFormat schro_pix_fmt)
136 {
137  int num_formats = sizeof(schro_pixel_format_map) /
138  sizeof(schro_pixel_format_map[0]);
139  int idx;
140 
141  for (idx = 0; idx < num_formats; ++idx)
142  if (schro_pixel_format_map[idx].schro_pix_fmt == schro_pix_fmt)
143  return schro_pixel_format_map[idx].ff_pix_fmt;
144  return AV_PIX_FMT_NONE;
145 }
146 
148 {
149 
150  SchroDecoderParams *p_schro_params = avctx->priv_data;
151  /* First of all, initialize our supporting libraries. */
152  schro_init();
153 
154  schro_debug_set_level(avctx->debug);
155  p_schro_params->decoder = schro_decoder_new();
156  schro_decoder_set_skip_ratio(p_schro_params->decoder, 1);
157 
158  if (!p_schro_params->decoder)
159  return -1;
160 
161  /* Initialize the decoded frame queue. */
162  ff_schro_queue_init(&p_schro_params->dec_frame_queue);
163  return 0;
164 }
165 
167 {
168  schro_frame_unref(frame);
169 }
170 
172 {
173  SchroDecoderParams *p_schro_params = avctx->priv_data;
174  SchroDecoder *decoder = p_schro_params->decoder;
175 
176  p_schro_params->format = schro_decoder_get_video_format(decoder);
177 
178  /* Tell FFmpeg about sequence details. */
179  if (av_image_check_size(p_schro_params->format->width,
180  p_schro_params->format->height, 0, avctx) < 0) {
181  av_log(avctx, AV_LOG_ERROR, "invalid dimensions (%dx%d)\n",
182  p_schro_params->format->width, p_schro_params->format->height);
183  avctx->height = avctx->width = 0;
184  return;
185  }
186  avctx->height = p_schro_params->format->height;
187  avctx->width = p_schro_params->format->width;
188  avctx->pix_fmt = get_chroma_format(p_schro_params->format->chroma_format);
189 
190  if (ff_get_schro_frame_format(p_schro_params->format->chroma_format,
191  &p_schro_params->frame_format) == -1) {
192  av_log(avctx, AV_LOG_ERROR,
193  "This codec currently only supports planar YUV 4:2:0, 4:2:2 "
194  "and 4:4:4 formats.\n");
195  return;
196  }
197 
198  avctx->time_base.den = p_schro_params->format->frame_rate_numerator;
199  avctx->time_base.num = p_schro_params->format->frame_rate_denominator;
200 }
201 
203  void *data, int *got_frame,
204  AVPacket *avpkt)
205 {
206  const uint8_t *buf = avpkt->data;
207  int buf_size = avpkt->size;
208  int64_t pts = avpkt->pts;
209  SchroTag *tag;
210 
211  SchroDecoderParams *p_schro_params = avctx->priv_data;
212  SchroDecoder *decoder = p_schro_params->decoder;
213  SchroBuffer *enc_buf;
214  SchroFrame* frame;
215  AVFrame *avframe = data;
216  int state;
217  int go = 1;
218  int outer = 1;
219  SchroParseUnitContext parse_ctx;
220  LibSchroFrameContext *framewithpts = NULL;
221 
222  *got_frame = 0;
223 
224  parse_context_init(&parse_ctx, buf, buf_size);
225  if (!buf_size) {
226  if (!p_schro_params->eos_signalled) {
227  state = schro_decoder_push_end_of_stream(decoder);
228  p_schro_params->eos_signalled = 1;
229  }
230  }
231 
232  /* Loop through all the individual parse units in the input buffer */
233  do {
234  if ((enc_buf = find_next_parse_unit(&parse_ctx))) {
235  /* Set Schrotag with the pts to be recovered after decoding*/
236  enc_buf->tag = schro_tag_new(av_malloc(sizeof(int64_t)), av_free);
237  if (!enc_buf->tag->value) {
238  av_log(avctx, AV_LOG_ERROR, "Unable to allocate SchroTag\n");
239  return AVERROR(ENOMEM);
240  }
241  AV_WN(64, enc_buf->tag->value, pts);
242  /* Push buffer into decoder. */
243  if (SCHRO_PARSE_CODE_IS_PICTURE(enc_buf->data[4]) &&
244  SCHRO_PARSE_CODE_NUM_REFS(enc_buf->data[4]) > 0)
245  avctx->has_b_frames = 1;
246  state = schro_decoder_push(decoder, enc_buf);
247  if (state == SCHRO_DECODER_FIRST_ACCESS_UNIT)
249  go = 1;
250  } else
251  outer = 0;
252 
253  while (go) {
254  /* Parse data and process result. */
255  state = schro_decoder_wait(decoder);
256  switch (state) {
257  case SCHRO_DECODER_FIRST_ACCESS_UNIT:
259  break;
260 
261  case SCHRO_DECODER_NEED_BITS:
262  /* Need more input data - stop iterating over what we have. */
263  go = 0;
264  break;
265 
266  case SCHRO_DECODER_NEED_FRAME:
267  /* Decoder needs a frame - create one and push it in. */
268  frame = ff_create_schro_frame(avctx,
269  p_schro_params->frame_format);
270  schro_decoder_add_output_picture(decoder, frame);
271  break;
272 
273  case SCHRO_DECODER_OK:
274  /* Pull a frame out of the decoder. */
275  tag = schro_decoder_get_picture_tag(decoder);
276  frame = schro_decoder_pull(decoder);
277 
278  if (frame) {
279  /* Add relation between schroframe and pts. */
280  framewithpts = av_malloc(sizeof(LibSchroFrameContext));
281  if (!framewithpts) {
282  av_log(avctx, AV_LOG_ERROR, "Unable to allocate FrameWithPts\n");
283  return AVERROR(ENOMEM);
284  }
285  framewithpts->frame = frame;
286  framewithpts->pts = AV_RN64(tag->value);
287  ff_schro_queue_push_back(&p_schro_params->dec_frame_queue,
288  framewithpts);
289  }
290  break;
291  case SCHRO_DECODER_EOS:
292  go = 0;
293  p_schro_params->eos_pulled = 1;
294  schro_decoder_reset(decoder);
295  outer = 0;
296  break;
297 
298  case SCHRO_DECODER_ERROR:
299  return -1;
300  break;
301  }
302  }
303  } while (outer);
304 
305  /* Grab next frame to be returned from the top of the queue. */
306  framewithpts = ff_schro_queue_pop(&p_schro_params->dec_frame_queue);
307 
308  if (framewithpts && framewithpts->frame) {
309  int ret;
310 
311  if ((ret = ff_get_buffer(avctx, avframe, 0)) < 0)
312  return ret;
313 
314  memcpy(avframe->data[0],
315  framewithpts->frame->components[0].data,
316  framewithpts->frame->components[0].length);
317 
318  memcpy(avframe->data[1],
319  framewithpts->frame->components[1].data,
320  framewithpts->frame->components[1].length);
321 
322  memcpy(avframe->data[2],
323  framewithpts->frame->components[2].data,
324  framewithpts->frame->components[2].length);
325 
326  /* Fill frame with current buffer data from Schroedinger. */
327  avframe->pkt_pts = framewithpts->pts;
328  avframe->linesize[0] = framewithpts->frame->components[0].stride;
329  avframe->linesize[1] = framewithpts->frame->components[1].stride;
330  avframe->linesize[2] = framewithpts->frame->components[2].stride;
331 
332  *got_frame = 1;
333 
334  /* Now free the frame resources. */
336  av_free(framewithpts);
337  } else {
338  data = NULL;
339  *got_frame = 0;
340  }
341  return buf_size;
342 }
343 
344 
346 {
347  SchroDecoderParams *p_schro_params = avctx->priv_data;
348  /* Free the decoder. */
349  schro_decoder_free(p_schro_params->decoder);
350  av_freep(&p_schro_params->format);
351 
352  /* Free data in the output frame queue. */
353  ff_schro_queue_free(&p_schro_params->dec_frame_queue,
355 
356  return 0;
357 }
358 
360 {
361  /* Got a seek request. Free the decoded frames queue and then reset
362  * the decoder */
363  SchroDecoderParams *p_schro_params = avctx->priv_data;
364 
365  /* Free data in the output frame queue. */
366  ff_schro_queue_free(&p_schro_params->dec_frame_queue,
368 
369  ff_schro_queue_init(&p_schro_params->dec_frame_queue);
370  schro_decoder_reset(p_schro_params->decoder);
371  p_schro_params->eos_pulled = 0;
372  p_schro_params->eos_signalled = 0;
373 }
374 
376  .name = "libschroedinger",
377  .long_name = NULL_IF_CONFIG_SMALL("libschroedinger Dirac 2.2"),
378  .type = AVMEDIA_TYPE_VIDEO,
379  .id = AV_CODEC_ID_DIRAC,
380  .priv_data_size = sizeof(SchroDecoderParams),
384  .capabilities = CODEC_CAP_DELAY,
386 };