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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
30 #include "libavutil/imgutils.h"
31 #include "avcodec.h"
32 #include "libdirac_libschro.h"
33 #include "libschroedinger.h"
34 
35 #undef NDEBUG
36 #include <assert.h>
37 
38 
39 #include <schroedinger/schro.h>
40 #include <schroedinger/schrodebug.h>
41 #include <schroedinger/schrovideoformat.h>
42 
44 typedef struct SchroDecoderParams {
46  SchroVideoFormat *format;
47 
49  SchroFrameFormat frame_format;
50 
52  SchroDecoder* decoder;
53 
56 
59 
62 
66 
67 typedef struct SchroParseUnitContext {
68  const uint8_t *buf;
69  int buf_size;
71 
72 
73 static void libschroedinger_decode_buffer_free(SchroBuffer *schro_buf,
74  void *priv);
75 
77  const uint8_t *buf, int buf_size)
78 {
79  parse_ctx->buf = buf;
80  parse_ctx->buf_size = buf_size;
81 }
82 
83 static SchroBuffer *FindNextSchroParseUnit(SchroParseUnitContext *parse_ctx)
84 {
85  SchroBuffer *enc_buf = NULL;
86  int next_pu_offset = 0;
87  unsigned char *in_buf;
88 
89  if (parse_ctx->buf_size < 13 ||
90  parse_ctx->buf[0] != 'B' ||
91  parse_ctx->buf[1] != 'B' ||
92  parse_ctx->buf[2] != 'C' ||
93  parse_ctx->buf[3] != 'D')
94  return NULL;
95 
96  next_pu_offset = (parse_ctx->buf[5] << 24) +
97  (parse_ctx->buf[6] << 16) +
98  (parse_ctx->buf[7] << 8) +
99  parse_ctx->buf[8];
100 
101  if (next_pu_offset == 0 &&
102  SCHRO_PARSE_CODE_IS_END_OF_SEQUENCE(parse_ctx->buf[4]))
103  next_pu_offset = 13;
104 
105  if (next_pu_offset <= 0 || parse_ctx->buf_size < next_pu_offset)
106  return NULL;
107 
108  in_buf = av_malloc(next_pu_offset);
109  memcpy(in_buf, parse_ctx->buf, next_pu_offset);
110  enc_buf = schro_buffer_new_with_data(in_buf, next_pu_offset);
111  enc_buf->free = libschroedinger_decode_buffer_free;
112  enc_buf->priv = in_buf;
113 
114  parse_ctx->buf += next_pu_offset;
115  parse_ctx->buf_size -= next_pu_offset;
116 
117  return enc_buf;
118 }
119 
123 static enum PixelFormat get_chroma_format(SchroChromaFormat schro_pix_fmt)
124 {
125  int num_formats = sizeof(schro_pixel_format_map) /
126  sizeof(schro_pixel_format_map[0]);
127  int idx;
128 
129  for (idx = 0; idx < num_formats; ++idx)
130  if (schro_pixel_format_map[idx].schro_pix_fmt == schro_pix_fmt)
131  return schro_pixel_format_map[idx].ff_pix_fmt;
132  return PIX_FMT_NONE;
133 }
134 
136 {
137 
138  SchroDecoderParams *p_schro_params = avccontext->priv_data;
139  /* First of all, initialize our supporting libraries. */
140  schro_init();
141 
142  schro_debug_set_level(avccontext->debug);
143  p_schro_params->decoder = schro_decoder_new();
144  schro_decoder_set_skip_ratio(p_schro_params->decoder, 1);
145 
146  if (!p_schro_params->decoder)
147  return -1;
148 
149  /* Initialize the decoded frame queue. */
150  ff_dirac_schro_queue_init(&p_schro_params->dec_frame_queue);
151  return 0;
152 }
153 
154 static void libschroedinger_decode_buffer_free(SchroBuffer *schro_buf,
155  void *priv)
156 {
157  av_freep(&priv);
158 }
159 
160 static void libschroedinger_decode_frame_free(void *frame)
161 {
162  schro_frame_unref(frame);
163 }
164 
166 {
167  SchroDecoderParams *p_schro_params = avccontext->priv_data;
168  SchroDecoder *decoder = p_schro_params->decoder;
169 
170  p_schro_params->format = schro_decoder_get_video_format(decoder);
171 
172  /* Tell Libav about sequence details. */
173  if (av_image_check_size(p_schro_params->format->width, p_schro_params->format->height,
174  0, avccontext) < 0) {
175  av_log(avccontext, AV_LOG_ERROR, "invalid dimensions (%dx%d)\n",
176  p_schro_params->format->width, p_schro_params->format->height);
177  avccontext->height = avccontext->width = 0;
178  return;
179  }
180  avccontext->height = p_schro_params->format->height;
181  avccontext->width = p_schro_params->format->width;
182  avccontext->pix_fmt = get_chroma_format(p_schro_params->format->chroma_format);
183 
184  if (ff_get_schro_frame_format(p_schro_params->format->chroma_format,
185  &p_schro_params->frame_format) == -1) {
186  av_log(avccontext, AV_LOG_ERROR,
187  "This codec currently only supports planar YUV 4:2:0, 4:2:2 "
188  "and 4:4:4 formats.\n");
189  return;
190  }
191 
192  avccontext->time_base.den = p_schro_params->format->frame_rate_numerator;
193  avccontext->time_base.num = p_schro_params->format->frame_rate_denominator;
194 
195  if (!p_schro_params->dec_pic.data[0])
196  avpicture_alloc(&p_schro_params->dec_pic,
197  avccontext->pix_fmt,
198  avccontext->width,
199  avccontext->height);
200 }
201 
203  void *data, int *data_size,
204  AVPacket *avpkt)
205 {
206  const uint8_t *buf = avpkt->data;
207  int buf_size = avpkt->size;
208 
209  SchroDecoderParams *p_schro_params = avccontext->priv_data;
210  SchroDecoder *decoder = p_schro_params->decoder;
212  SchroBuffer *enc_buf;
213  SchroFrame* frame;
214  int state;
215  int go = 1;
216  int outer = 1;
217  SchroParseUnitContext parse_ctx;
218 
219  *data_size = 0;
220 
221  SchroParseContextInit(&parse_ctx, buf, buf_size);
222  if (!buf_size) {
223  if (!p_schro_params->eos_signalled) {
224  state = schro_decoder_push_end_of_stream(decoder);
225  p_schro_params->eos_signalled = 1;
226  }
227  }
228 
229  /* Loop through all the individual parse units in the input buffer */
230  do {
231  if ((enc_buf = FindNextSchroParseUnit(&parse_ctx))) {
232  /* Push buffer into decoder. */
233  if (SCHRO_PARSE_CODE_IS_PICTURE(enc_buf->data[4]) &&
234  SCHRO_PARSE_CODE_NUM_REFS(enc_buf->data[4]) > 0)
235  avccontext->has_b_frames = 1;
236  state = schro_decoder_push(decoder, enc_buf);
237  if (state == SCHRO_DECODER_FIRST_ACCESS_UNIT)
239  go = 1;
240  } else
241  outer = 0;
242 
243  while (go) {
244  /* Parse data and process result. */
245  state = schro_decoder_wait(decoder);
246  switch (state) {
247  case SCHRO_DECODER_FIRST_ACCESS_UNIT:
249  break;
250 
251  case SCHRO_DECODER_NEED_BITS:
252  /* Need more input data - stop iterating over what we have. */
253  go = 0;
254  break;
255 
256  case SCHRO_DECODER_NEED_FRAME:
257  /* Decoder needs a frame - create one and push it in. */
258  frame = ff_create_schro_frame(avccontext,
259  p_schro_params->frame_format);
260  schro_decoder_add_output_picture(decoder, frame);
261  break;
262 
263  case SCHRO_DECODER_OK:
264  /* Pull a frame out of the decoder. */
265  frame = schro_decoder_pull(decoder);
266 
267  if (frame)
269  frame);
270  break;
271  case SCHRO_DECODER_EOS:
272  go = 0;
273  p_schro_params->eos_pulled = 1;
274  schro_decoder_reset(decoder);
275  outer = 0;
276  break;
277 
278  case SCHRO_DECODER_ERROR:
279  return -1;
280  break;
281  }
282  }
283  } while (outer);
284 
285  /* Grab next frame to be returned from the top of the queue. */
286  frame = ff_dirac_schro_queue_pop(&p_schro_params->dec_frame_queue);
287 
288  if (frame) {
289  memcpy(p_schro_params->dec_pic.data[0],
290  frame->components[0].data,
291  frame->components[0].length);
292 
293  memcpy(p_schro_params->dec_pic.data[1],
294  frame->components[1].data,
295  frame->components[1].length);
296 
297  memcpy(p_schro_params->dec_pic.data[2],
298  frame->components[2].data,
299  frame->components[2].length);
300 
301  /* Fill picture with current buffer data from Schroedinger. */
302  avpicture_fill(picture, p_schro_params->dec_pic.data[0],
303  avccontext->pix_fmt,
304  avccontext->width, avccontext->height);
305 
306  *data_size = sizeof(AVPicture);
307 
308  /* Now free the frame resources. */
310  }
311  return buf_size;
312 }
313 
314 
316 {
317  SchroDecoderParams *p_schro_params = avccontext->priv_data;
318  /* Free the decoder. */
319  schro_decoder_free(p_schro_params->decoder);
320  av_freep(&p_schro_params->format);
321 
322  avpicture_free(&p_schro_params->dec_pic);
323 
324  /* Free data in the output frame queue. */
327 
328  return 0;
329 }
330 
331 static void libschroedinger_flush(AVCodecContext *avccontext)
332 {
333  /* Got a seek request. Free the decoded frames queue and then reset
334  * the decoder */
335  SchroDecoderParams *p_schro_params = avccontext->priv_data;
336 
337  /* Free data in the output frame queue. */
340 
341  ff_dirac_schro_queue_init(&p_schro_params->dec_frame_queue);
342  schro_decoder_reset(p_schro_params->decoder);
343  p_schro_params->eos_pulled = 0;
344  p_schro_params->eos_signalled = 0;
345 }
346 
348  .name = "libschroedinger",
349  .type = AVMEDIA_TYPE_VIDEO,
350  .id = CODEC_ID_DIRAC,
351  .priv_data_size = sizeof(SchroDecoderParams),
355  .capabilities = CODEC_CAP_DELAY,
357  .long_name = NULL_IF_CONFIG_SMALL("libschroedinger Dirac 2.2"),
358 };