FFmpeg: libavformat/yuv4mpegdec.c Source File

FFmpeg
yuv4mpegdec.c
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1 /*
2  * YUV4MPEG demuxer
3  * Copyright (c) 2001, 2002, 2003 Fabrice Bellard
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 #include "avformat.h"
23 #include "internal.h"
24 #include "yuv4mpeg.h"
25 
26 /* Header size increased to allow room for optional flags */
27  #define MAX_YUV4_HEADER 80
28  #define MAX_FRAME_HEADER 80
29 
30  static int yuv4_read_header(AVFormatContext *s)
31 {
32  char header[MAX_YUV4_HEADER + 10]; // Include headroom for
33  // the longest option
34  char *tokstart, *tokend, *header_end;
35  int i;
36  AVIOContext *pb = s->pb;
37  int width = -1, height = -1, raten = 0,
38  rated = 0, aspectn = 0, aspectd = 0;
39  enum AVPixelFormat pix_fmt = AV_PIX_FMT_NONE, alt_pix_fmt = AV_PIX_FMT_NONE;
40  enum AVChromaLocation chroma_sample_location = AVCHROMA_LOC_UNSPECIFIED;
41  enum AVFieldOrder field_order = AV_FIELD_UNKNOWN;
42  AVStream *st;
43 
44  for (i = 0; i < MAX_YUV4_HEADER; i++) {
45  header[i] = avio_r8(pb);
46  if (header[i] == '\n') {
47  header[i + 1] = 0x20; // Add a space after last option.
48  // Makes parsing "444" vs "444alpha" easier.
49  header[i + 2] = 0;
50  break;
51  }
52  }
53  if (i == MAX_YUV4_HEADER)
54  return -1;
55  if (strncmp(header, Y4M_MAGIC, strlen(Y4M_MAGIC)))
56  return -1;
57 
58  header_end = &header[i + 1]; // Include space
59  for (tokstart = &header[strlen(Y4M_MAGIC) + 1];
60  tokstart < header_end; tokstart++) {
61  if (*tokstart == 0x20)
62  continue;
63  switch (*tokstart++) {
64  case 'W': // Width. Required.
65  width = strtol(tokstart, &tokend, 10);
66  tokstart = tokend;
67  break;
68  case 'H': // Height. Required.
69  height = strtol(tokstart, &tokend, 10);
70  tokstart = tokend;
71  break;
72  case 'C': // Color space
73  if (strncmp("420jpeg", tokstart, 7) == 0) {
74  pix_fmt = AV_PIX_FMT_YUV420P;
75  chroma_sample_location = AVCHROMA_LOC_CENTER;
76  } else if (strncmp("420mpeg2", tokstart, 8) == 0) {
77  pix_fmt = AV_PIX_FMT_YUV420P;
78  chroma_sample_location = AVCHROMA_LOC_LEFT;
79  } else if (strncmp("420paldv", tokstart, 8) == 0) {
80  pix_fmt = AV_PIX_FMT_YUV420P;
81  chroma_sample_location = AVCHROMA_LOC_TOPLEFT;
82  } else if (strncmp("420p16", tokstart, 6) == 0) {
83  pix_fmt = AV_PIX_FMT_YUV420P16;
84  } else if (strncmp("422p16", tokstart, 6) == 0) {
85  pix_fmt = AV_PIX_FMT_YUV422P16;
86  } else if (strncmp("444p16", tokstart, 6) == 0) {
87  pix_fmt = AV_PIX_FMT_YUV444P16;
88  } else if (strncmp("420p14", tokstart, 6) == 0) {
89  pix_fmt = AV_PIX_FMT_YUV420P14;
90  } else if (strncmp("422p14", tokstart, 6) == 0) {
91  pix_fmt = AV_PIX_FMT_YUV422P14;
92  } else if (strncmp("444p14", tokstart, 6) == 0) {
93  pix_fmt = AV_PIX_FMT_YUV444P14;
94  } else if (strncmp("420p12", tokstart, 6) == 0) {
95  pix_fmt = AV_PIX_FMT_YUV420P12;
96  } else if (strncmp("422p12", tokstart, 6) == 0) {
97  pix_fmt = AV_PIX_FMT_YUV422P12;
98  } else if (strncmp("444p12", tokstart, 6) == 0) {
99  pix_fmt = AV_PIX_FMT_YUV444P12;
100  } else if (strncmp("420p10", tokstart, 6) == 0) {
101  pix_fmt = AV_PIX_FMT_YUV420P10;
102  } else if (strncmp("422p10", tokstart, 6) == 0) {
103  pix_fmt = AV_PIX_FMT_YUV422P10;
104  } else if (strncmp("444p10", tokstart, 6) == 0) {
105  pix_fmt = AV_PIX_FMT_YUV444P10;
106  } else if (strncmp("420p9", tokstart, 5) == 0) {
107  pix_fmt = AV_PIX_FMT_YUV420P9;
108  } else if (strncmp("422p9", tokstart, 5) == 0) {
109  pix_fmt = AV_PIX_FMT_YUV422P9;
110  } else if (strncmp("444p9", tokstart, 5) == 0) {
111  pix_fmt = AV_PIX_FMT_YUV444P9;
112  } else if (strncmp("420", tokstart, 3) == 0) {
113  pix_fmt = AV_PIX_FMT_YUV420P;
114  chroma_sample_location = AVCHROMA_LOC_CENTER;
115  } else if (strncmp("411", tokstart, 3) == 0) {
116  pix_fmt = AV_PIX_FMT_YUV411P;
117  } else if (strncmp("422", tokstart, 3) == 0) {
118  pix_fmt = AV_PIX_FMT_YUV422P;
119  } else if (strncmp("444alpha", tokstart, 8) == 0 ) {
120  av_log(s, AV_LOG_ERROR, "Cannot handle 4:4:4:4 "
121  "YUV4MPEG stream.\n");
122  return -1;
123  } else if (strncmp("444", tokstart, 3) == 0) {
124  pix_fmt = AV_PIX_FMT_YUV444P;
125  } else if (strncmp("mono16", tokstart, 6) == 0) {
126  pix_fmt = AV_PIX_FMT_GRAY16;
127  } else if (strncmp("mono", tokstart, 4) == 0) {
128  pix_fmt = AV_PIX_FMT_GRAY8;
129  } else {
130  av_log(s, AV_LOG_ERROR, "YUV4MPEG stream contains an unknown "
131  "pixel format.\n");
132  return -1;
133  }
134  while (tokstart < header_end && *tokstart != 0x20)
135  tokstart++;
136  break;
137  case 'I': // Interlace type
138  switch (*tokstart++){
139  case '?':
140  field_order = AV_FIELD_UNKNOWN;
141  break;
142  case 'p':
143  field_order = AV_FIELD_PROGRESSIVE;
144  break;
145  case 't':
146  field_order = AV_FIELD_TT;
147  break;
148  case 'b':
149  field_order = AV_FIELD_BB;
150  break;
151  case 'm':
152  av_log(s, AV_LOG_ERROR, "YUV4MPEG stream contains mixed "
153  "interlaced and non-interlaced frames.\n");
154  default:
155  av_log(s, AV_LOG_ERROR, "YUV4MPEG has invalid header.\n");
156  return AVERROR(EINVAL);
157  }
158  break;
159  case 'F': // Frame rate
160  sscanf(tokstart, "%d:%d", &raten, &rated); // 0:0 if unknown
161  while (tokstart < header_end && *tokstart != 0x20)
162  tokstart++;
163  break;
164  case 'A': // Pixel aspect
165  sscanf(tokstart, "%d:%d", &aspectn, &aspectd); // 0:0 if unknown
166  while (tokstart < header_end && *tokstart != 0x20)
167  tokstart++;
168  break;
169  case 'X': // Vendor extensions
170  if (strncmp("YSCSS=", tokstart, 6) == 0) {
171  // Older nonstandard pixel format representation
172  tokstart += 6;
173  if (strncmp("420JPEG", tokstart, 7) == 0)
174  alt_pix_fmt = AV_PIX_FMT_YUV420P;
175  else if (strncmp("420MPEG2", tokstart, 8) == 0)
176  alt_pix_fmt = AV_PIX_FMT_YUV420P;
177  else if (strncmp("420PALDV", tokstart, 8) == 0)
178  alt_pix_fmt = AV_PIX_FMT_YUV420P;
179  else if (strncmp("420P9", tokstart, 5) == 0)
180  alt_pix_fmt = AV_PIX_FMT_YUV420P9;
181  else if (strncmp("422P9", tokstart, 5) == 0)
182  alt_pix_fmt = AV_PIX_FMT_YUV422P9;
183  else if (strncmp("444P9", tokstart, 5) == 0)
184  alt_pix_fmt = AV_PIX_FMT_YUV444P9;
185  else if (strncmp("420P10", tokstart, 6) == 0)
186  alt_pix_fmt = AV_PIX_FMT_YUV420P10;
187  else if (strncmp("422P10", tokstart, 6) == 0)
188  alt_pix_fmt = AV_PIX_FMT_YUV422P10;
189  else if (strncmp("444P10", tokstart, 6) == 0)
190  alt_pix_fmt = AV_PIX_FMT_YUV444P10;
191  else if (strncmp("420P12", tokstart, 6) == 0)
192  alt_pix_fmt = AV_PIX_FMT_YUV420P12;
193  else if (strncmp("422P12", tokstart, 6) == 0)
194  alt_pix_fmt = AV_PIX_FMT_YUV422P12;
195  else if (strncmp("444P12", tokstart, 6) == 0)
196  alt_pix_fmt = AV_PIX_FMT_YUV444P12;
197  else if (strncmp("420P14", tokstart, 6) == 0)
198  alt_pix_fmt = AV_PIX_FMT_YUV420P14;
199  else if (strncmp("422P14", tokstart, 6) == 0)
200  alt_pix_fmt = AV_PIX_FMT_YUV422P14;
201  else if (strncmp("444P14", tokstart, 6) == 0)
202  alt_pix_fmt = AV_PIX_FMT_YUV444P14;
203  else if (strncmp("420P16", tokstart, 6) == 0)
204  alt_pix_fmt = AV_PIX_FMT_YUV420P16;
205  else if (strncmp("422P16", tokstart, 6) == 0)
206  alt_pix_fmt = AV_PIX_FMT_YUV422P16;
207  else if (strncmp("444P16", tokstart, 6) == 0)
208  alt_pix_fmt = AV_PIX_FMT_YUV444P16;
209  else if (strncmp("411", tokstart, 3) == 0)
210  alt_pix_fmt = AV_PIX_FMT_YUV411P;
211  else if (strncmp("422", tokstart, 3) == 0)
212  alt_pix_fmt = AV_PIX_FMT_YUV422P;
213  else if (strncmp("444", tokstart, 3) == 0)
214  alt_pix_fmt = AV_PIX_FMT_YUV444P;
215  }
216  while (tokstart < header_end && *tokstart != 0x20)
217  tokstart++;
218  break;
219  }
220  }
221 
222  if (width == -1 || height == -1) {
223  av_log(s, AV_LOG_ERROR, "YUV4MPEG has invalid header.\n");
224  return -1;
225  }
226 
227  if (pix_fmt == AV_PIX_FMT_NONE) {
228  if (alt_pix_fmt == AV_PIX_FMT_NONE)
229  pix_fmt = AV_PIX_FMT_YUV420P;
230  else
231  pix_fmt = alt_pix_fmt;
232  }
233 
234  if (raten <= 0 || rated <= 0) {
235  // Frame rate unknown
236  raten = 25;
237  rated = 1;
238  }
239 
240  if (aspectn == 0 && aspectd == 0) {
241  // Pixel aspect unknown
242  aspectd = 1;
243  }
244 
245  st = avformat_new_stream(s, NULL);
246  if (!st)
247  return AVERROR(ENOMEM);
248  st->codec->width = width;
249  st->codec->height = height;
250  av_reduce(&raten, &rated, raten, rated, (1UL << 31) - 1);
251  avpriv_set_pts_info(st, 64, rated, raten);
252  st->avg_frame_rate = av_inv_q(st->time_base);
253  st->codec->pix_fmt = pix_fmt;
254  st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
255  st->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
256  st->sample_aspect_ratio = (AVRational){ aspectn, aspectd };
257  st->codec->chroma_sample_location = chroma_sample_location;
258  st->codec->field_order = field_order;
259 
260  return 0;
261 }
262 
263  static int yuv4_read_packet(AVFormatContext *s, AVPacket *pkt)
264 {
265  int i;
266  char header[MAX_FRAME_HEADER+1];
267  int packet_size, width, height, ret;
268  AVStream *st = s->streams[0];
269 
270  for (i = 0; i < MAX_FRAME_HEADER; i++) {
271  header[i] = avio_r8(s->pb);
272  if (header[i] == '\n') {
273  header[i + 1] = 0;
274  break;
275  }
276  }
277  if (s->pb->error)
278  return s->pb->error;
279  else if (s->pb->eof_reached)
280  return AVERROR_EOF;
281  else if (i == MAX_FRAME_HEADER)
282  return AVERROR_INVALIDDATA;
283 
284  if (strncmp(header, Y4M_FRAME_MAGIC, strlen(Y4M_FRAME_MAGIC)))
285  return AVERROR_INVALIDDATA;
286 
287  width = st->codec->width;
288  height = st->codec->height;
289 
290  packet_size = avpicture_get_size(st->codec->pix_fmt, width, height);
291  if (packet_size < 0)
292  return packet_size;
293 
294  ret = av_get_packet(s->pb, pkt, packet_size);
295  if (ret < 0)
296  return ret;
297  else if (ret != packet_size)
298  return s->pb->eof_reached ? AVERROR_EOF : AVERROR(EIO);
299 
300  pkt->stream_index = 0;
301  return 0;
302 }
303 
304  static int yuv4_probe(AVProbeData *pd)
305 {
306  /* check file header */
307  if (strncmp(pd->buf, Y4M_MAGIC, sizeof(Y4M_MAGIC) - 1) == 0)
308  return AVPROBE_SCORE_MAX;
309  else
310  return 0;
311 }
312 
313  AVInputFormat ff_yuv4mpegpipe_demuxer = {
314  .name = "yuv4mpegpipe",
315  .long_name = NULL_IF_CONFIG_SMALL("YUV4MPEG pipe"),
316  .read_probe = yuv4_probe,
317  .read_header = yuv4_read_header,
318  .read_packet = yuv4_read_packet,
319  .extensions = "y4m",
320 };
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