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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  if (ff_get_extradata(vst->codec, pb, size) < 0)
90  return AVERROR(ENOMEM);
91  size = 0;
92  if (!myth)
93  return 0;
94  }
95  break;
96  case NUV_MYTHEXT:
97  avio_skip(pb, 7);
98  size = PKTSIZE(avio_rl32(pb));
99  if (size != 128 * 4)
100  break;
101  avio_rl32(pb); // version
102  if (vst) {
103  vst->codec->codec_tag = avio_rl32(pb);
104  vst->codec->codec_id =
106  if (vst->codec->codec_tag == MKTAG('R', 'J', 'P', 'G'))
108  } else
109  avio_skip(pb, 4);
110 
111  if (ast) {
112  int id;
113 
114  ast->codec->codec_tag = avio_rl32(pb);
115  ast->codec->sample_rate = avio_rl32(pb);
117  ast->codec->channels = avio_rl32(pb);
118  ast->codec->channel_layout = 0;
119 
122  if (id == AV_CODEC_ID_NONE) {
123  id = ff_codec_get_id(nuv_audio_tags, ast->codec->codec_tag);
124  if (id == AV_CODEC_ID_PCM_S16LE)
126  0, 0, ~1);
127  }
128  ast->codec->codec_id = id;
129 
131  } else
132  avio_skip(pb, 4 * 4);
133 
134  size -= 6 * 4;
135  avio_skip(pb, size);
136  return 0;
137  case NUV_SEEKP:
138  size = 11;
139  break;
140  default:
141  avio_skip(pb, 7);
142  size = PKTSIZE(avio_rl32(pb));
143  break;
144  }
145  avio_skip(pb, size);
146  }
147 
148  return 0;
149 }
150 
152 {
153  NUVContext *ctx = s->priv_data;
154  AVIOContext *pb = s->pb;
155  char id_string[12];
156  double aspect, fps;
157  int is_mythtv, width, height, v_packs, a_packs, ret;
158  AVStream *vst = NULL, *ast = NULL;
159 
160  avio_read(pb, id_string, 12);
161  is_mythtv = !memcmp(id_string, "MythTVVideo", 12);
162  avio_skip(pb, 5); // version string
163  avio_skip(pb, 3); // padding
164  width = avio_rl32(pb);
165  height = avio_rl32(pb);
166  avio_rl32(pb); // unused, "desiredwidth"
167  avio_rl32(pb); // unused, "desiredheight"
168  avio_r8(pb); // 'P' == progressive, 'I' == interlaced
169  avio_skip(pb, 3); // padding
170  aspect = av_int2double(avio_rl64(pb));
171  if (aspect > 0.9999 && aspect < 1.0001)
172  aspect = 4.0 / 3.0;
173  fps = av_int2double(avio_rl64(pb));
174 
175  // number of packets per stream type, -1 means unknown, e.g. streaming
176  v_packs = avio_rl32(pb);
177  a_packs = avio_rl32(pb);
178  avio_rl32(pb); // text
179 
180  avio_rl32(pb); // keyframe distance (?)
181 
182  if (v_packs) {
183  vst = avformat_new_stream(s, NULL);
184  if (!vst)
185  return AVERROR(ENOMEM);
186  ctx->v_id = vst->index;
187 
190  vst->codec->width = width;
191  vst->codec->height = height;
192  vst->codec->bits_per_coded_sample = 10;
193  vst->sample_aspect_ratio = av_d2q(aspect * height / width,
194  10000);
195 #if FF_API_R_FRAME_RATE
196  vst->r_frame_rate =
197 #endif
198  vst->avg_frame_rate = av_d2q(fps, 60000);
199  avpriv_set_pts_info(vst, 32, 1, 1000);
200  } else
201  ctx->v_id = -1;
202 
203  if (a_packs) {
204  ast = avformat_new_stream(s, NULL);
205  if (!ast)
206  return AVERROR(ENOMEM);
207  ctx->a_id = ast->index;
208 
209  ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
210  ast->codec->codec_id = AV_CODEC_ID_PCM_S16LE;
211  ast->codec->channels = 2;
212  ast->codec->channel_layout = AV_CH_LAYOUT_STEREO;
213  ast->codec->sample_rate = 44100;
214  ast->codec->bit_rate = 2 * 2 * 44100 * 8;
215  ast->codec->block_align = 2 * 2;
216  ast->codec->bits_per_coded_sample = 16;
217  avpriv_set_pts_info(ast, 32, 1, 1000);
218  } else
219  ctx->a_id = -1;
220 
221  if ((ret = get_codec_data(pb, vst, ast, is_mythtv)) < 0)
222  return ret;
223 
224  ctx->rtjpg_video = vst && vst->codec->codec_id == AV_CODEC_ID_NUV;
225 
226  return 0;
227 }
228 
229 #define HDRSIZE 12
230 
232 {
233  NUVContext *ctx = s->priv_data;
234  AVIOContext *pb = s->pb;
235  uint8_t hdr[HDRSIZE];
236  nuv_frametype frametype;
237  int ret, size;
238 
239  while (!url_feof(pb)) {
240  int copyhdrsize = ctx->rtjpg_video ? HDRSIZE : 0;
241  uint64_t pos = avio_tell(pb);
242 
243  ret = avio_read(pb, hdr, HDRSIZE);
244  if (ret < HDRSIZE)
245  return ret < 0 ? ret : AVERROR(EIO);
246 
247  frametype = hdr[0];
248  size = PKTSIZE(AV_RL32(&hdr[8]));
249 
250  switch (frametype) {
251  case NUV_EXTRADATA:
252  if (!ctx->rtjpg_video) {
253  avio_skip(pb, size);
254  break;
255  }
256  case NUV_VIDEO:
257  if (ctx->v_id < 0) {
258  av_log(s, AV_LOG_ERROR, "Video packet in file without video stream!\n");
259  avio_skip(pb, size);
260  break;
261  }
262  ret = av_new_packet(pkt, copyhdrsize + size);
263  if (ret < 0)
264  return ret;
265 
266  pkt->pos = pos;
267  pkt->flags |= hdr[2] == 0 ? AV_PKT_FLAG_KEY : 0;
268  pkt->pts = AV_RL32(&hdr[4]);
269  pkt->stream_index = ctx->v_id;
270  memcpy(pkt->data, hdr, copyhdrsize);
271  ret = avio_read(pb, pkt->data + copyhdrsize, size);
272  if (ret < 0) {
273  av_free_packet(pkt);
274  return ret;
275  }
276  if (ret < size)
277  av_shrink_packet(pkt, copyhdrsize + ret);
278  return 0;
279  case NUV_AUDIO:
280  if (ctx->a_id < 0) {
281  av_log(s, AV_LOG_ERROR, "Audio packet in file without audio stream!\n");
282  avio_skip(pb, size);
283  break;
284  }
285  ret = av_get_packet(pb, pkt, size);
286  pkt->flags |= AV_PKT_FLAG_KEY;
287  pkt->pos = pos;
288  pkt->pts = AV_RL32(&hdr[4]);
289  pkt->stream_index = ctx->a_id;
290  if (ret < 0)
291  return ret;
292  return 0;
293  case NUV_SEEKP:
294  // contains no data, size value is invalid
295  break;
296  default:
297  avio_skip(pb, size);
298  break;
299  }
300  }
301 
302  return AVERROR(EIO);
303 }
304 
305 /**
306  * \brief looks for the string RTjjjjjjjjjj in the stream too resync reading
307  * \return 1 if the syncword is found 0 otherwise.
308  */
309 static int nuv_resync(AVFormatContext *s, int64_t pos_limit) {
310  AVIOContext *pb = s->pb;
311  uint32_t tag = 0;
312  while(!url_feof(pb) && avio_tell(pb) < pos_limit) {
313  tag = (tag << 8) | avio_r8(pb);
314  if (tag == MKBETAG('R','T','j','j') &&
315  (tag = avio_rb32(pb)) == MKBETAG('j','j','j','j') &&
316  (tag = avio_rb32(pb)) == MKBETAG('j','j','j','j'))
317  return 1;
318  }
319  return 0;
320 }
321 
322 /**
323  * \brief attempts to read a timestamp from stream at the given stream position
324  * \return timestamp if successful and AV_NOPTS_VALUE if failure
325  */
326 static int64_t nuv_read_dts(AVFormatContext *s, int stream_index,
327  int64_t *ppos, int64_t pos_limit)
328 {
329  NUVContext *ctx = s->priv_data;
330  AVIOContext *pb = s->pb;
331  uint8_t hdr[HDRSIZE];
332  nuv_frametype frametype;
333  int size, key, idx;
334  int64_t pos, dts;
335 
336  if (avio_seek(pb, *ppos, SEEK_SET) < 0)
337  return AV_NOPTS_VALUE;
338 
339  if (!nuv_resync(s, pos_limit))
340  return AV_NOPTS_VALUE;
341 
342  while (!url_feof(pb) && avio_tell(pb) < pos_limit) {
343  if (avio_read(pb, hdr, HDRSIZE) < HDRSIZE)
344  return AV_NOPTS_VALUE;
345  frametype = hdr[0];
346  size = PKTSIZE(AV_RL32(&hdr[8]));
347  switch (frametype) {
348  case NUV_SEEKP:
349  break;
350  case NUV_AUDIO:
351  case NUV_VIDEO:
352  if (frametype == NUV_VIDEO) {
353  idx = ctx->v_id;
354  key = hdr[2] == 0;
355  } else {
356  idx = ctx->a_id;
357  key = 1;
358  }
359  if (stream_index == idx) {
360 
361  pos = avio_tell(s->pb) - HDRSIZE;
362  dts = AV_RL32(&hdr[4]);
363 
364  // TODO - add general support in av_gen_search, so it adds positions after reading timestamps
365  av_add_index_entry(s->streams[stream_index], pos, dts, size + HDRSIZE, 0,
366  key ? AVINDEX_KEYFRAME : 0);
367 
368  *ppos = pos;
369  return dts;
370  }
371  default:
372  avio_skip(pb, size);
373  break;
374  }
375  }
376  return AV_NOPTS_VALUE;
377 }
378 
379 
381  .name = "nuv",
382  .long_name = NULL_IF_CONFIG_SMALL("NuppelVideo"),
383  .priv_data_size = sizeof(NUVContext),
387  .read_timestamp = nuv_read_dts,
389 };