yuv4mpeg.c
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1 /*
2  * YUV4MPEG format
3  * Copyright (c) 2001, 2002, 2003 Fabrice Bellard
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 #include "avformat.h"
22 #include "internal.h"
23 
24 #define Y4M_MAGIC "YUV4MPEG2"
25 #define Y4M_FRAME_MAGIC "FRAME"
26 #define Y4M_LINE_MAX 256
27 
31 };
32 
33 #if CONFIG_YUV4MPEGPIPE_MUXER
34 static int yuv4_generate_header(AVFormatContext *s, char* buf)
35 {
36  AVStream *st;
37  int width, height;
38  int raten, rated, aspectn, aspectd, n;
39  char inter;
40  const char *colorspace = "";
41 
42  st = s->streams[0];
43  width = st->codec->width;
44  height = st->codec->height;
45 
46  av_reduce(&raten, &rated, st->codec->time_base.den,
47  st->codec->time_base.num, (1UL << 31) - 1);
48 
49  aspectn = st->sample_aspect_ratio.num;
50  aspectd = st->sample_aspect_ratio.den;
51 
52  if (aspectn == 0 && aspectd == 1)
53  aspectd = 0; // 0:0 means unknown
54 
55  inter = 'p'; /* progressive is the default */
57  inter = st->codec->coded_frame->top_field_first ? 't' : 'b';
58 
59  switch (st->codec->pix_fmt) {
60  case PIX_FMT_GRAY8:
61  colorspace = " Cmono";
62  break;
63  case PIX_FMT_YUV411P:
64  colorspace = " C411 XYSCSS=411";
65  break;
66  case PIX_FMT_YUV420P:
67  switch (st->codec->chroma_sample_location) {
68  case AVCHROMA_LOC_TOPLEFT: colorspace = " C420paldv XYSCSS=420PALDV"; break;
69  case AVCHROMA_LOC_LEFT: colorspace = " C420mpeg2 XYSCSS=420MPEG2"; break;
70  default: colorspace = " C420jpeg XYSCSS=420JPEG"; break;
71  }
72  break;
73  case PIX_FMT_YUV422P:
74  colorspace = " C422 XYSCSS=422";
75  break;
76  case PIX_FMT_YUV444P:
77  colorspace = " C444 XYSCSS=444";
78  break;
79  }
80 
81  /* construct stream header, if this is the first frame */
82  n = snprintf(buf, Y4M_LINE_MAX, "%s W%d H%d F%d:%d I%c A%d:%d%s\n",
83  Y4M_MAGIC, width, height, raten, rated, inter,
84  aspectn, aspectd, colorspace);
85 
86  return n;
87 }
88 
89 static int yuv4_write_packet(AVFormatContext *s, AVPacket *pkt)
90 {
91  AVStream *st = s->streams[pkt->stream_index];
92  AVIOContext *pb = s->pb;
94  int* first_pkt = s->priv_data;
95  int width, height, h_chroma_shift, v_chroma_shift;
96  int i;
97  char buf2[Y4M_LINE_MAX + 1];
98  char buf1[20];
99  uint8_t *ptr, *ptr1, *ptr2;
100 
101  picture = (AVPicture *)pkt->data;
102 
103  /* for the first packet we have to output the header as well */
104  if (*first_pkt) {
105  *first_pkt = 0;
106  if (yuv4_generate_header(s, buf2) < 0) {
107  av_log(s, AV_LOG_ERROR,
108  "Error. YUV4MPEG stream header write failed.\n");
109  return AVERROR(EIO);
110  } else {
111  avio_write(pb, buf2, strlen(buf2));
112  }
113  }
114 
115  /* construct frame header */
116 
117  snprintf(buf1, sizeof(buf1), "%s\n", Y4M_FRAME_MAGIC);
118  avio_write(pb, buf1, strlen(buf1));
119 
120  width = st->codec->width;
121  height = st->codec->height;
122 
123  ptr = picture->data[0];
124  for (i = 0; i < height; i++) {
125  avio_write(pb, ptr, width);
126  ptr += picture->linesize[0];
127  }
128 
129  if (st->codec->pix_fmt != PIX_FMT_GRAY8) {
130  // Adjust for smaller Cb and Cr planes
131  avcodec_get_chroma_sub_sample(st->codec->pix_fmt, &h_chroma_shift,
132  &v_chroma_shift);
133  width >>= h_chroma_shift;
134  height >>= v_chroma_shift;
135 
136  ptr1 = picture->data[1];
137  ptr2 = picture->data[2];
138  for (i = 0; i < height; i++) { /* Cb */
139  avio_write(pb, ptr1, width);
140  ptr1 += picture->linesize[1];
141  }
142  for (i = 0; i < height; i++) { /* Cr */
143  avio_write(pb, ptr2, width);
144  ptr2 += picture->linesize[2];
145  }
146  }
147  avio_flush(pb);
148  return 0;
149 }
150 
151 static int yuv4_write_header(AVFormatContext *s)
152 {
153  int *first_pkt = s->priv_data;
154 
155  if (s->nb_streams != 1)
156  return AVERROR(EIO);
157 
158  if (s->streams[0]->codec->pix_fmt == PIX_FMT_YUV411P) {
159  av_log(s, AV_LOG_ERROR, "Warning: generating rarely used 4:1:1 YUV "
160  "stream, some mjpegtools might not work.\n");
161  } else if ((s->streams[0]->codec->pix_fmt != PIX_FMT_YUV420P) &&
162  (s->streams[0]->codec->pix_fmt != PIX_FMT_YUV422P) &&
163  (s->streams[0]->codec->pix_fmt != PIX_FMT_GRAY8) &&
164  (s->streams[0]->codec->pix_fmt != PIX_FMT_YUV444P)) {
165  av_log(s, AV_LOG_ERROR, "ERROR: yuv4mpeg only handles yuv444p, "
166  "yuv422p, yuv420p, yuv411p and gray pixel formats. "
167  "Use -pix_fmt to select one.\n");
168  return AVERROR(EIO);
169  }
170 
171  *first_pkt = 1;
172  return 0;
173 }
174 
175 AVOutputFormat ff_yuv4mpegpipe_muxer = {
176  .name = "yuv4mpegpipe",
177  .long_name = NULL_IF_CONFIG_SMALL("YUV4MPEG pipe format"),
178  .mime_type = "",
179  .extensions = "y4m",
180  .priv_data_size = sizeof(int),
181  .audio_codec = CODEC_ID_NONE,
182  .video_codec = CODEC_ID_RAWVIDEO,
183  .write_header = yuv4_write_header,
184  .write_packet = yuv4_write_packet,
186 };
187 #endif
188 
189 /* Header size increased to allow room for optional flags */
190 #define MAX_YUV4_HEADER 80
191 #define MAX_FRAME_HEADER 80
192 
194 {
195  char header[MAX_YUV4_HEADER + 10]; // Include headroom for
196  // the longest option
197  char *tokstart, *tokend, *header_end;
198  int i;
199  AVIOContext *pb = s->pb;
200  int width = -1, height = -1, raten = 0,
201  rated = 0, aspectn = 0, aspectd = 0;
202  enum PixelFormat pix_fmt = PIX_FMT_NONE, alt_pix_fmt = PIX_FMT_NONE;
203  enum AVChromaLocation chroma_sample_location = AVCHROMA_LOC_UNSPECIFIED;
204  AVStream *st;
205  struct frame_attributes *s1 = s->priv_data;
206 
207  for (i = 0; i < MAX_YUV4_HEADER; i++) {
208  header[i] = avio_r8(pb);
209  if (header[i] == '\n') {
210  header[i + 1] = 0x20; // Add a space after last option.
211  // Makes parsing "444" vs "444alpha" easier.
212  header[i + 2] = 0;
213  break;
214  }
215  }
216  if (i == MAX_YUV4_HEADER)
217  return -1;
218  if (strncmp(header, Y4M_MAGIC, strlen(Y4M_MAGIC)))
219  return -1;
220 
221  s1->interlaced_frame = 0;
222  s1->top_field_first = 0;
223  header_end = &header[i + 1]; // Include space
224  for (tokstart = &header[strlen(Y4M_MAGIC) + 1];
225  tokstart < header_end; tokstart++) {
226  if (*tokstart == 0x20)
227  continue;
228  switch (*tokstart++) {
229  case 'W': // Width. Required.
230  width = strtol(tokstart, &tokend, 10);
231  tokstart = tokend;
232  break;
233  case 'H': // Height. Required.
234  height = strtol(tokstart, &tokend, 10);
235  tokstart = tokend;
236  break;
237  case 'C': // Color space
238  if (strncmp("420jpeg", tokstart, 7) == 0) {
239  pix_fmt = PIX_FMT_YUV420P;
240  chroma_sample_location = AVCHROMA_LOC_CENTER;
241  } else if (strncmp("420mpeg2", tokstart, 8) == 0) {
242  pix_fmt = PIX_FMT_YUV420P;
243  chroma_sample_location = AVCHROMA_LOC_LEFT;
244  } else if (strncmp("420paldv", tokstart, 8) == 0) {
245  pix_fmt = PIX_FMT_YUV420P;
246  chroma_sample_location = AVCHROMA_LOC_TOPLEFT;
247  } else if (strncmp("411", tokstart, 3) == 0)
248  pix_fmt = PIX_FMT_YUV411P;
249  else if (strncmp("422", tokstart, 3) == 0)
250  pix_fmt = PIX_FMT_YUV422P;
251  else if (strncmp("444alpha", tokstart, 8) == 0 ) {
252  av_log(s, AV_LOG_ERROR, "Cannot handle 4:4:4:4 "
253  "YUV4MPEG stream.\n");
254  return -1;
255  } else if (strncmp("444", tokstart, 3) == 0)
256  pix_fmt = PIX_FMT_YUV444P;
257  else if (strncmp("mono", tokstart, 4) == 0) {
258  pix_fmt = PIX_FMT_GRAY8;
259  } else {
260  av_log(s, AV_LOG_ERROR, "YUV4MPEG stream contains an unknown "
261  "pixel format.\n");
262  return -1;
263  }
264  while (tokstart < header_end && *tokstart != 0x20)
265  tokstart++;
266  break;
267  case 'I': // Interlace type
268  switch (*tokstart++){
269  case '?':
270  break;
271  case 'p':
272  s1->interlaced_frame = 0;
273  break;
274  case 't':
275  s1->interlaced_frame = 1;
276  s1->top_field_first = 1;
277  break;
278  case 'b':
279  s1->interlaced_frame = 1;
280  s1->top_field_first = 0;
281  break;
282  case 'm':
283  av_log(s, AV_LOG_ERROR, "YUV4MPEG stream contains mixed "
284  "interlaced and non-interlaced frames.\n");
285  return -1;
286  default:
287  av_log(s, AV_LOG_ERROR, "YUV4MPEG has invalid header.\n");
288  return -1;
289  }
290  break;
291  case 'F': // Frame rate
292  sscanf(tokstart, "%d:%d", &raten, &rated); // 0:0 if unknown
293  while (tokstart < header_end && *tokstart != 0x20)
294  tokstart++;
295  break;
296  case 'A': // Pixel aspect
297  sscanf(tokstart, "%d:%d", &aspectn, &aspectd); // 0:0 if unknown
298  while (tokstart < header_end && *tokstart != 0x20)
299  tokstart++;
300  break;
301  case 'X': // Vendor extensions
302  if (strncmp("YSCSS=", tokstart, 6) == 0) {
303  // Older nonstandard pixel format representation
304  tokstart += 6;
305  if (strncmp("420JPEG", tokstart, 7) == 0)
306  alt_pix_fmt = PIX_FMT_YUV420P;
307  else if (strncmp("420MPEG2", tokstart, 8) == 0)
308  alt_pix_fmt = PIX_FMT_YUV420P;
309  else if (strncmp("420PALDV", tokstart, 8) == 0)
310  alt_pix_fmt = PIX_FMT_YUV420P;
311  else if (strncmp("411", tokstart, 3) == 0)
312  alt_pix_fmt = PIX_FMT_YUV411P;
313  else if (strncmp("422", tokstart, 3) == 0)
314  alt_pix_fmt = PIX_FMT_YUV422P;
315  else if (strncmp("444", tokstart, 3) == 0)
316  alt_pix_fmt = PIX_FMT_YUV444P;
317  }
318  while (tokstart < header_end && *tokstart != 0x20)
319  tokstart++;
320  break;
321  }
322  }
323 
324  if (width == -1 || height == -1) {
325  av_log(s, AV_LOG_ERROR, "YUV4MPEG has invalid header.\n");
326  return -1;
327  }
328 
329  if (pix_fmt == PIX_FMT_NONE) {
330  if (alt_pix_fmt == PIX_FMT_NONE)
331  pix_fmt = PIX_FMT_YUV420P;
332  else
333  pix_fmt = alt_pix_fmt;
334  }
335 
336  if (raten <= 0 || rated <= 0) {
337  // Frame rate unknown
338  raten = 25;
339  rated = 1;
340  }
341 
342  if (aspectn == 0 && aspectd == 0) {
343  // Pixel aspect unknown
344  aspectd = 1;
345  }
346 
347  st = avformat_new_stream(s, NULL);
348  if (!st)
349  return AVERROR(ENOMEM);
350  st->codec->width = width;
351  st->codec->height = height;
352  av_reduce(&raten, &rated, raten, rated, (1UL << 31) - 1);
353  avpriv_set_pts_info(st, 64, rated, raten);
354  st->codec->pix_fmt = pix_fmt;
357  st->sample_aspect_ratio = (AVRational){ aspectn, aspectd };
358  st->codec->chroma_sample_location = chroma_sample_location;
359 
360  return 0;
361 }
362 
364 {
365  int i;
366  char header[MAX_FRAME_HEADER+1];
367  int packet_size, width, height;
368  AVStream *st = s->streams[0];
369  struct frame_attributes *s1 = s->priv_data;
370 
371  for (i = 0; i < MAX_FRAME_HEADER; i++) {
372  header[i] = avio_r8(s->pb);
373  if (header[i] == '\n') {
374  header[i + 1] = 0;
375  break;
376  }
377  }
378  if (i == MAX_FRAME_HEADER)
379  return -1;
380  if (strncmp(header, Y4M_FRAME_MAGIC, strlen(Y4M_FRAME_MAGIC)))
381  return -1;
382 
383  width = st->codec->width;
384  height = st->codec->height;
385 
386  packet_size = avpicture_get_size(st->codec->pix_fmt, width, height);
387  if (packet_size < 0)
388  return -1;
389 
390  if (av_get_packet(s->pb, pkt, packet_size) != packet_size)
391  return AVERROR(EIO);
392 
393  if (st->codec->coded_frame) {
396  }
397 
398  pkt->stream_index = 0;
399  return 0;
400 }
401 
402 static int yuv4_probe(AVProbeData *pd)
403 {
404  /* check file header */
405  if (strncmp(pd->buf, Y4M_MAGIC, sizeof(Y4M_MAGIC) - 1) == 0)
406  return AVPROBE_SCORE_MAX;
407  else
408  return 0;
409 }
410 
411 #if CONFIG_YUV4MPEGPIPE_DEMUXER
412 AVInputFormat ff_yuv4mpegpipe_demuxer = {
413  .name = "yuv4mpegpipe",
414  .long_name = NULL_IF_CONFIG_SMALL("YUV4MPEG pipe format"),
415  .priv_data_size = sizeof(struct frame_attributes),
417  .read_header = yuv4_read_header,
418  .read_packet = yuv4_read_packet,
419  .extensions = "y4m"
420 };
421 #endif