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nuv.c
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1 /*
2  * NuppelVideo demuxer.
3  * Copyright (c) 2006 Reimar Doeffinger
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 
23 #include "libavutil/intreadwrite.h"
24 #include "libavutil/intfloat.h"
25 #include "avformat.h"
26 #include "internal.h"
27 #include "riff.h"
28 
29 static const AVCodecTag nuv_audio_tags[] = {
30  { AV_CODEC_ID_PCM_S16LE, MKTAG('R', 'A', 'W', 'A') },
31  { AV_CODEC_ID_MP3, MKTAG('L', 'A', 'M', 'E') },
32  { AV_CODEC_ID_NONE, 0 },
33 };
34 
35 typedef struct {
36  int v_id;
37  int a_id;
39 } NUVContext;
40 
41 typedef enum {
42  NUV_VIDEO = 'V',
44  NUV_AUDIO = 'A',
45  NUV_SEEKP = 'R',
48 
49 static int nuv_probe(AVProbeData *p)
50 {
51  if (!memcmp(p->buf, "NuppelVideo", 12))
52  return AVPROBE_SCORE_MAX;
53  if (!memcmp(p->buf, "MythTVVideo", 12))
54  return AVPROBE_SCORE_MAX;
55  return 0;
56 }
57 
58 /// little macro to sanitize packet size
59 #define PKTSIZE(s) (s & 0xffffff)
60 
61 /**
62  * @brief read until we found all data needed for decoding
63  * @param vst video stream of which to change parameters
64  * @param ast video stream of which to change parameters
65  * @param myth set if this is a MythTVVideo format file
66  * @return 0 or AVERROR code
67  */
68 static int get_codec_data(AVIOContext *pb, AVStream *vst,
69  AVStream *ast, int myth)
70 {
71  nuv_frametype frametype;
72 
73  if (!vst && !myth)
74  return 1; // no codec data needed
75  while (!url_feof(pb)) {
76  int size, subtype;
77 
78  frametype = avio_r8(pb);
79  switch (frametype) {
80  case NUV_EXTRADATA:
81  subtype = avio_r8(pb);
82  avio_skip(pb, 6);
83  size = PKTSIZE(avio_rl32(pb));
84  if (vst && subtype == 'R') {
85  if (vst->codec->extradata) {
86  av_freep(&vst->codec->extradata);
87  vst->codec->extradata_size = 0;
88  }
89  vst->codec->extradata = av_malloc(size);
90  if (!vst->codec->extradata)
91  return AVERROR(ENOMEM);
92  vst->codec->extradata_size = size;
93  avio_read(pb, vst->codec->extradata, size);
94  size = 0;
95  if (!myth)
96  return 0;
97  }
98  break;
99  case NUV_MYTHEXT:
100  avio_skip(pb, 7);
101  size = PKTSIZE(avio_rl32(pb));
102  if (size != 128 * 4)
103  break;
104  avio_rl32(pb); // version
105  if (vst) {
106  vst->codec->codec_tag = avio_rl32(pb);
107  vst->codec->codec_id =
109  if (vst->codec->codec_tag == MKTAG('R', 'J', 'P', 'G'))
111  } else
112  avio_skip(pb, 4);
113 
114  if (ast) {
115  int id;
116 
117  ast->codec->codec_tag = avio_rl32(pb);
118  ast->codec->sample_rate = avio_rl32(pb);
120  ast->codec->channels = avio_rl32(pb);
121  ast->codec->channel_layout = 0;
122 
125  if (id == AV_CODEC_ID_NONE) {
126  id = ff_codec_get_id(nuv_audio_tags, ast->codec->codec_tag);
127  if (id == AV_CODEC_ID_PCM_S16LE)
129  0, 0, ~1);
130  }
131  ast->codec->codec_id = id;
132 
134  } else
135  avio_skip(pb, 4 * 4);
136 
137  size -= 6 * 4;
138  avio_skip(pb, size);
139  return 0;
140  case NUV_SEEKP:
141  size = 11;
142  break;
143  default:
144  avio_skip(pb, 7);
145  size = PKTSIZE(avio_rl32(pb));
146  break;
147  }
148  avio_skip(pb, size);
149  }
150 
151  return 0;
152 }
153 
155 {
156  NUVContext *ctx = s->priv_data;
157  AVIOContext *pb = s->pb;
158  char id_string[12];
159  double aspect, fps;
160  int is_mythtv, width, height, v_packs, a_packs, ret;
161  AVStream *vst = NULL, *ast = NULL;
162 
163  avio_read(pb, id_string, 12);
164  is_mythtv = !memcmp(id_string, "MythTVVideo", 12);
165  avio_skip(pb, 5); // version string
166  avio_skip(pb, 3); // padding
167  width = avio_rl32(pb);
168  height = avio_rl32(pb);
169  avio_rl32(pb); // unused, "desiredwidth"
170  avio_rl32(pb); // unused, "desiredheight"
171  avio_r8(pb); // 'P' == progressive, 'I' == interlaced
172  avio_skip(pb, 3); // padding
173  aspect = av_int2double(avio_rl64(pb));
174  if (aspect > 0.9999 && aspect < 1.0001)
175  aspect = 4.0 / 3.0;
176  fps = av_int2double(avio_rl64(pb));
177 
178  // number of packets per stream type, -1 means unknown, e.g. streaming
179  v_packs = avio_rl32(pb);
180  a_packs = avio_rl32(pb);
181  avio_rl32(pb); // text
182 
183  avio_rl32(pb); // keyframe distance (?)
184 
185  if (v_packs) {
186  vst = avformat_new_stream(s, NULL);
187  if (!vst)
188  return AVERROR(ENOMEM);
189  ctx->v_id = vst->index;
190 
193  vst->codec->width = width;
194  vst->codec->height = height;
195  vst->codec->bits_per_coded_sample = 10;
196  vst->sample_aspect_ratio = av_d2q(aspect * height / width,
197  10000);
198 #if FF_API_R_FRAME_RATE
199  vst->r_frame_rate =
200 #endif
201  vst->avg_frame_rate = av_d2q(fps, 60000);
202  avpriv_set_pts_info(vst, 32, 1, 1000);
203  } else
204  ctx->v_id = -1;
205 
206  if (a_packs) {
207  ast = avformat_new_stream(s, NULL);
208  if (!ast)
209  return AVERROR(ENOMEM);
210  ctx->a_id = ast->index;
211 
212  ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
213  ast->codec->codec_id = AV_CODEC_ID_PCM_S16LE;
214  ast->codec->channels = 2;
215  ast->codec->channel_layout = AV_CH_LAYOUT_STEREO;
216  ast->codec->sample_rate = 44100;
217  ast->codec->bit_rate = 2 * 2 * 44100 * 8;
218  ast->codec->block_align = 2 * 2;
219  ast->codec->bits_per_coded_sample = 16;
220  avpriv_set_pts_info(ast, 32, 1, 1000);
221  } else
222  ctx->a_id = -1;
223 
224  if ((ret = get_codec_data(pb, vst, ast, is_mythtv)) < 0)
225  return ret;
226 
227  ctx->rtjpg_video = vst && vst->codec->codec_id == AV_CODEC_ID_NUV;
228 
229  return 0;
230 }
231 
232 #define HDRSIZE 12
233 
235 {
236  NUVContext *ctx = s->priv_data;
237  AVIOContext *pb = s->pb;
238  uint8_t hdr[HDRSIZE];
239  nuv_frametype frametype;
240  int ret, size;
241 
242  while (!url_feof(pb)) {
243  int copyhdrsize = ctx->rtjpg_video ? HDRSIZE : 0;
244  uint64_t pos = avio_tell(pb);
245 
246  ret = avio_read(pb, hdr, HDRSIZE);
247  if (ret < HDRSIZE)
248  return ret < 0 ? ret : AVERROR(EIO);
249 
250  frametype = hdr[0];
251  size = PKTSIZE(AV_RL32(&hdr[8]));
252 
253  switch (frametype) {
254  case NUV_EXTRADATA:
255  if (!ctx->rtjpg_video) {
256  avio_skip(pb, size);
257  break;
258  }
259  case NUV_VIDEO:
260  if (ctx->v_id < 0) {
261  av_log(s, AV_LOG_ERROR, "Video packet in file without video stream!\n");
262  avio_skip(pb, size);
263  break;
264  }
265  ret = av_new_packet(pkt, copyhdrsize + size);
266  if (ret < 0)
267  return ret;
268 
269  pkt->pos = pos;
270  pkt->flags |= hdr[2] == 0 ? AV_PKT_FLAG_KEY : 0;
271  pkt->pts = AV_RL32(&hdr[4]);
272  pkt->stream_index = ctx->v_id;
273  memcpy(pkt->data, hdr, copyhdrsize);
274  ret = avio_read(pb, pkt->data + copyhdrsize, size);
275  if (ret < 0) {
276  av_free_packet(pkt);
277  return ret;
278  }
279  if (ret < size)
280  av_shrink_packet(pkt, copyhdrsize + ret);
281  return 0;
282  case NUV_AUDIO:
283  if (ctx->a_id < 0) {
284  av_log(s, AV_LOG_ERROR, "Audio packet in file without audio stream!\n");
285  avio_skip(pb, size);
286  break;
287  }
288  ret = av_get_packet(pb, pkt, size);
289  pkt->flags |= AV_PKT_FLAG_KEY;
290  pkt->pos = pos;
291  pkt->pts = AV_RL32(&hdr[4]);
292  pkt->stream_index = ctx->a_id;
293  if (ret < 0)
294  return ret;
295  return 0;
296  case NUV_SEEKP:
297  // contains no data, size value is invalid
298  break;
299  default:
300  avio_skip(pb, size);
301  break;
302  }
303  }
304 
305  return AVERROR(EIO);
306 }
307 
308 /**
309  * \brief looks for the string RTjjjjjjjjjj in the stream too resync reading
310  * \return 1 if the syncword is found 0 otherwise.
311  */
312 static int nuv_resync(AVFormatContext *s, int64_t pos_limit) {
313  AVIOContext *pb = s->pb;
314  uint32_t tag = 0;
315  while(!url_feof(pb) && avio_tell(pb) < pos_limit) {
316  tag = (tag << 8) | avio_r8(pb);
317  if (tag == MKBETAG('R','T','j','j') &&
318  (tag = avio_rb32(pb)) == MKBETAG('j','j','j','j') &&
319  (tag = avio_rb32(pb)) == MKBETAG('j','j','j','j'))
320  return 1;
321  }
322  return 0;
323 }
324 
325 /**
326  * \brief attempts to read a timestamp from stream at the given stream position
327  * \return timestamp if successful and AV_NOPTS_VALUE if failure
328  */
329 static int64_t nuv_read_dts(AVFormatContext *s, int stream_index,
330  int64_t *ppos, int64_t pos_limit)
331 {
332  NUVContext *ctx = s->priv_data;
333  AVIOContext *pb = s->pb;
334  uint8_t hdr[HDRSIZE];
335  nuv_frametype frametype;
336  int size, key, idx;
337  int64_t pos, dts;
338 
339  if (avio_seek(pb, *ppos, SEEK_SET) < 0)
340  return AV_NOPTS_VALUE;
341 
342  if (!nuv_resync(s, pos_limit))
343  return AV_NOPTS_VALUE;
344 
345  while (!url_feof(pb) && avio_tell(pb) < pos_limit) {
346  if (avio_read(pb, hdr, HDRSIZE) < HDRSIZE)
347  return AV_NOPTS_VALUE;
348  frametype = hdr[0];
349  size = PKTSIZE(AV_RL32(&hdr[8]));
350  switch (frametype) {
351  case NUV_SEEKP:
352  break;
353  case NUV_AUDIO:
354  case NUV_VIDEO:
355  if (frametype == NUV_VIDEO) {
356  idx = ctx->v_id;
357  key = hdr[2] == 0;
358  } else {
359  idx = ctx->a_id;
360  key = 1;
361  }
362  if (stream_index == idx) {
363 
364  pos = avio_tell(s->pb) - HDRSIZE;
365  dts = AV_RL32(&hdr[4]);
366 
367  // TODO - add general support in av_gen_search, so it adds positions after reading timestamps
368  av_add_index_entry(s->streams[stream_index], pos, dts, size + HDRSIZE, 0,
369  key ? AVINDEX_KEYFRAME : 0);
370 
371  *ppos = pos;
372  return dts;
373  }
374  default:
375  avio_skip(pb, size);
376  break;
377  }
378  }
379  return AV_NOPTS_VALUE;
380 }
381 
382 
384  .name = "nuv",
385  .long_name = NULL_IF_CONFIG_SMALL("NuppelVideo"),
386  .priv_data_size = sizeof(NUVContext),
390  .read_timestamp = nuv_read_dts,
392 };