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libnut.c
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1 /*
2  * NUT (de)muxing via libnut
3  * copyright (c) 2006 Oded Shimon <ods15@ods15.dyndns.org>
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 /**
23  * @file
24  * NUT demuxing and muxing via libnut.
25  * @author Oded Shimon <ods15@ods15.dyndns.org>
26  */
27 
28 #include "avformat.h"
29 #include "internal.h"
30 #include "riff.h"
31 #include <libnut.h>
32 
33 #define ID_STRING "nut/multimedia container"
34 #define ID_LENGTH (strlen(ID_STRING) + 1)
35 
36 typedef struct {
37  nut_context_tt * nut;
38  nut_stream_header_tt * s;
39 } NUTContext;
40 
41 static const AVCodecTag nut_tags[] = {
42  { AV_CODEC_ID_MPEG4, MKTAG('m', 'p', '4', 'v') },
43  { AV_CODEC_ID_MP3, MKTAG('m', 'p', '3', ' ') },
44  { AV_CODEC_ID_VORBIS, MKTAG('v', 'r', 'b', 's') },
45  { 0, 0 },
46 };
47 
48 #if CONFIG_LIBNUT_MUXER
49 static int av_write(void * h, size_t len, const uint8_t * buf) {
50  AVIOContext * bc = h;
51  avio_write(bc, buf, len);
52  //avio_flush(bc);
53  return len;
54 }
55 
56 static int nut_write_header(AVFormatContext * avf) {
57  NUTContext * priv = avf->priv_data;
58  AVIOContext * bc = avf->pb;
59  nut_muxer_opts_tt mopts = {
60  .output = {
61  .priv = bc,
62  .write = av_write,
63  },
64  .alloc = { av_malloc, av_realloc, av_free },
65  .write_index = 1,
66  .realtime_stream = 0,
67  .max_distance = 32768,
68  .fti = NULL,
69  };
70  nut_stream_header_tt * s;
71  int i;
72 
73  priv->s = s = av_mallocz((avf->nb_streams + 1) * sizeof*s);
74  if(!s)
75  return AVERROR(ENOMEM);
76 
77  for (i = 0; i < avf->nb_streams; i++) {
78  AVCodecContext * codec = avf->streams[i]->codec;
79  int j;
80  int fourcc = 0;
81  int num, denom, ssize;
82 
83  s[i].type = codec->codec_type == AVMEDIA_TYPE_VIDEO ? NUT_VIDEO_CLASS : NUT_AUDIO_CLASS;
84 
85  if (codec->codec_tag) fourcc = codec->codec_tag;
86  else fourcc = ff_codec_get_tag(nut_tags, codec->codec_id);
87 
88  if (!fourcc) {
91  }
92 
93  s[i].fourcc_len = 4;
94  s[i].fourcc = av_malloc(s[i].fourcc_len);
95  for (j = 0; j < s[i].fourcc_len; j++) s[i].fourcc[j] = (fourcc >> (j*8)) & 0xFF;
96 
97  ff_parse_specific_params(codec, &num, &ssize, &denom);
98  avpriv_set_pts_info(avf->streams[i], 60, denom, num);
99 
100  s[i].time_base.num = denom;
101  s[i].time_base.den = num;
102 
103  s[i].fixed_fps = 0;
104  s[i].decode_delay = codec->has_b_frames;
105  s[i].codec_specific_len = codec->extradata_size;
106  s[i].codec_specific = codec->extradata;
107 
108  if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {
109  s[i].width = codec->width;
110  s[i].height = codec->height;
111  s[i].sample_width = 0;
112  s[i].sample_height = 0;
113  s[i].colorspace_type = 0;
114  } else {
115  s[i].samplerate_num = codec->sample_rate;
116  s[i].samplerate_denom = 1;
117  s[i].channel_count = codec->channels;
118  }
119  }
120 
121  s[avf->nb_streams].type = -1;
122  priv->nut = nut_muxer_init(&mopts, s, NULL);
123 
124  return 0;
125 }
126 
127 static int nut_write_packet(AVFormatContext * avf, AVPacket * pkt) {
128  NUTContext * priv = avf->priv_data;
129  nut_packet_tt p;
130 
131  p.len = pkt->size;
132  p.stream = pkt->stream_index;
133  p.pts = pkt->pts;
134  p.flags = pkt->flags & AV_PKT_FLAG_KEY ? NUT_FLAG_KEY : 0;
135  p.next_pts = 0;
136 
137  nut_write_frame_reorder(priv->nut, &p, pkt->data);
138 
139  return 0;
140 }
141 
142 static int nut_write_trailer(AVFormatContext * avf) {
143  AVIOContext * bc = avf->pb;
144  NUTContext * priv = avf->priv_data;
145  int i;
146 
147  nut_muxer_uninit_reorder(priv->nut);
148  avio_flush(bc);
149 
150  for(i = 0; priv->s[i].type != -1; i++ ) av_freep(&priv->s[i].fourcc);
151  av_freep(&priv->s);
152 
153  return 0;
154 }
155 
156 AVOutputFormat ff_libnut_muxer = {
157  .name = "libnut",
158  .long_name = "nut format",
159  .mime_type = "video/x-nut",
160  .extensions = "nut",
161  .priv_data_size = sizeof(NUTContext),
162  .audio_codec = AV_CODEC_ID_VORBIS,
163  .video_codec = AV_CODEC_ID_MPEG4,
168 };
169 #endif /* CONFIG_LIBNUT_MUXER */
170 
171 static int nut_probe(AVProbeData *p) {
172  if (!memcmp(p->buf, ID_STRING, ID_LENGTH)) return AVPROBE_SCORE_MAX;
173 
174  return 0;
175 }
176 
177 static size_t av_read(void * h, size_t len, uint8_t * buf) {
178  AVIOContext * bc = h;
179  return avio_read(bc, buf, len);
180 }
181 
182 static off_t av_seek(void * h, long long pos, int whence) {
183  AVIOContext * bc = h;
184  if (whence == SEEK_END) {
185  pos = avio_size(bc) + pos;
186  whence = SEEK_SET;
187  }
188  return avio_seek(bc, pos, whence);
189 }
190 
191 static int nut_read_header(AVFormatContext * avf) {
192  NUTContext * priv = avf->priv_data;
193  AVIOContext * bc = avf->pb;
194  nut_demuxer_opts_tt dopts = {
195  .input = {
196  .priv = bc,
197  .seek = av_seek,
198  .read = av_read,
199  .eof = NULL,
200  .file_pos = 0,
201  },
202  .alloc = { av_malloc, av_realloc, av_free },
203  .read_index = 1,
204  .cache_syncpoints = 1,
205  };
206  nut_context_tt * nut = priv->nut = nut_demuxer_init(&dopts);
207  nut_stream_header_tt * s;
208  int ret, i;
209 
210  if(!nut)
211  return -1;
212 
213  if ((ret = nut_read_headers(nut, &s, NULL))) {
214  av_log(avf, AV_LOG_ERROR, " NUT error: %s\n", nut_error(ret));
215  nut_demuxer_uninit(nut);
216  priv->nut = NULL;
217  return -1;
218  }
219 
220  priv->s = s;
221 
222  for (i = 0; s[i].type != -1 && i < 2; i++) {
223  AVStream * st = avformat_new_stream(avf, NULL);
224  int j;
225 
226  if (!st)
227  return AVERROR(ENOMEM);
228 
229  for (j = 0; j < s[i].fourcc_len && j < 8; j++) st->codec->codec_tag |= s[i].fourcc[j]<<(j*8);
230 
231  st->codec->has_b_frames = s[i].decode_delay;
232 
233  st->codec->extradata_size = s[i].codec_specific_len;
234  if (st->codec->extradata_size) {
236  nut_demuxer_uninit(nut);
237  priv->nut = NULL;
238  return AVERROR(ENOMEM);
239  }
240  memcpy(st->codec->extradata, s[i].codec_specific, st->codec->extradata_size);
241  }
242 
243  avpriv_set_pts_info(avf->streams[i], 60, s[i].time_base.num, s[i].time_base.den);
244  st->start_time = 0;
245  st->duration = s[i].max_pts;
246 
247  st->codec->codec_id = ff_codec_get_id(nut_tags, st->codec->codec_tag);
248 
249  switch(s[i].type) {
250  case NUT_AUDIO_CLASS:
253 
254  st->codec->channels = s[i].channel_count;
255  st->codec->sample_rate = s[i].samplerate_num / s[i].samplerate_denom;
256  break;
257  case NUT_VIDEO_CLASS:
260 
261  st->codec->width = s[i].width;
262  st->codec->height = s[i].height;
263  st->sample_aspect_ratio.num = s[i].sample_width;
264  st->sample_aspect_ratio.den = s[i].sample_height;
265  break;
266  }
267  if (st->codec->codec_id == AV_CODEC_ID_NONE) av_log(avf, AV_LOG_ERROR, "Unknown codec?!\n");
268  }
269 
270  return 0;
271 }
272 
274  NUTContext * priv = avf->priv_data;
275  nut_packet_tt pd;
276  int ret;
277 
278  ret = nut_read_next_packet(priv->nut, &pd);
279 
280  if (ret || av_new_packet(pkt, pd.len) < 0) {
281  if (ret != NUT_ERR_EOF)
282  av_log(avf, AV_LOG_ERROR, " NUT error: %s\n", nut_error(ret));
283  return -1;
284  }
285 
286  if (pd.flags & NUT_FLAG_KEY) pkt->flags |= AV_PKT_FLAG_KEY;
287  pkt->pts = pd.pts;
288  pkt->stream_index = pd.stream;
289  pkt->pos = avio_tell(avf->pb);
290 
291  ret = nut_read_frame(priv->nut, &pd.len, pkt->data);
292 
293  return ret;
294 }
295 
296 static int nut_read_seek(AVFormatContext * avf, int stream_index, int64_t target_ts, int flags) {
297  NUTContext * priv = avf->priv_data;
298  int active_streams[] = { stream_index, -1 };
299  double time_pos = target_ts * priv->s[stream_index].time_base.num / (double)priv->s[stream_index].time_base.den;
300 
301  if (nut_seek(priv->nut, time_pos, 2*!(flags & AVSEEK_FLAG_BACKWARD), active_streams)) return -1;
302 
303  return 0;
304 }
305 
307  NUTContext * priv = s->priv_data;
308 
309  nut_demuxer_uninit(priv->nut);
310 
311  return 0;
312 }
313 
315  .name = "libnut",
316  .long_name = NULL_IF_CONFIG_SMALL("NUT format"),
317  .priv_data_size = sizeof(NUTContext),
323  .extensions = "nut",
324 };