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 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 
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  { CODEC_ID_MPEG4, MKTAG('m', 'p', '4', 'v') },
43  { CODEC_ID_MP3, MKTAG('m', 'p', '3', ' ') },
44  { 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 
75  for (i = 0; i < avf->nb_streams; i++) {
76  AVCodecContext * codec = avf->streams[i]->codec;
77  int j;
78  int fourcc = 0;
79  int num, denom, ssize;
80 
81  s[i].type = codec->codec_type == AVMEDIA_TYPE_VIDEO ? NUT_VIDEO_CLASS : NUT_AUDIO_CLASS;
82 
83  if (codec->codec_tag) fourcc = codec->codec_tag;
84  else fourcc = ff_codec_get_tag(nut_tags, codec->codec_id);
85 
86  if (!fourcc) {
89  }
90 
91  s[i].fourcc_len = 4;
92  s[i].fourcc = av_malloc(s[i].fourcc_len);
93  for (j = 0; j < s[i].fourcc_len; j++) s[i].fourcc[j] = (fourcc >> (j*8)) & 0xFF;
94 
95  ff_parse_specific_params(codec, &num, &ssize, &denom);
96  avpriv_set_pts_info(avf->streams[i], 60, denom, num);
97 
98  s[i].time_base.num = denom;
99  s[i].time_base.den = num;
100 
101  s[i].fixed_fps = 0;
102  s[i].decode_delay = codec->has_b_frames;
103  s[i].codec_specific_len = codec->extradata_size;
104  s[i].codec_specific = codec->extradata;
105 
106  if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {
107  s[i].width = codec->width;
108  s[i].height = codec->height;
109  s[i].sample_width = 0;
110  s[i].sample_height = 0;
111  s[i].colorspace_type = 0;
112  } else {
113  s[i].samplerate_num = codec->sample_rate;
114  s[i].samplerate_denom = 1;
115  s[i].channel_count = codec->channels;
116  }
117  }
118 
119  s[avf->nb_streams].type = -1;
120  priv->nut = nut_muxer_init(&mopts, s, NULL);
121 
122  return 0;
123 }
124 
125 static int nut_write_packet(AVFormatContext * avf, AVPacket * pkt) {
126  NUTContext * priv = avf->priv_data;
127  nut_packet_tt p;
128 
129  p.len = pkt->size;
130  p.stream = pkt->stream_index;
131  p.pts = pkt->pts;
132  p.flags = pkt->flags & AV_PKT_FLAG_KEY ? NUT_FLAG_KEY : 0;
133  p.next_pts = 0;
134 
135  nut_write_frame_reorder(priv->nut, &p, pkt->data);
136 
137  return 0;
138 }
139 
140 static int nut_write_trailer(AVFormatContext * avf) {
141  AVIOContext * bc = avf->pb;
142  NUTContext * priv = avf->priv_data;
143  int i;
144 
145  nut_muxer_uninit_reorder(priv->nut);
146  avio_flush(bc);
147 
148  for(i = 0; priv->s[i].type != -1; i++ ) av_freep(&priv->s[i].fourcc);
149  av_freep(&priv->s);
150 
151  return 0;
152 }
153 
154 AVOutputFormat ff_libnut_muxer = {
155  .name = "libnut",
156  .long_name = "nut format",
157  .mime_type = "video/x-nut",
158  .extensions = "nut",
159  .priv_data_size = sizeof(NUTContext),
160  .audio_codec = CODEC_ID_VORBIS,
161  .video_codec = CODEC_ID_MPEG4,
166 };
167 #endif /* CONFIG_LIBNUT_MUXER */
168 
169 static int nut_probe(AVProbeData *p) {
170  if (!memcmp(p->buf, ID_STRING, ID_LENGTH)) return AVPROBE_SCORE_MAX;
171 
172  return 0;
173 }
174 
175 static size_t av_read(void * h, size_t len, uint8_t * buf) {
176  AVIOContext * bc = h;
177  return avio_read(bc, buf, len);
178 }
179 
180 static off_t av_seek(void * h, long long pos, int whence) {
181  AVIOContext * bc = h;
182  if (whence == SEEK_END) {
183  pos = avio_size(bc) + pos;
184  whence = SEEK_SET;
185  }
186  return avio_seek(bc, pos, whence);
187 }
188 
190  NUTContext * priv = avf->priv_data;
191  AVIOContext * bc = avf->pb;
192  nut_demuxer_opts_tt dopts = {
193  .input = {
194  .priv = bc,
195  .seek = av_seek,
196  .read = av_read,
197  .eof = NULL,
198  .file_pos = 0,
199  },
200  .alloc = { av_malloc, av_realloc, av_free },
201  .read_index = 1,
202  .cache_syncpoints = 1,
203  };
204  nut_context_tt * nut = priv->nut = nut_demuxer_init(&dopts);
205  nut_stream_header_tt * s;
206  int ret, i;
207 
208  if ((ret = nut_read_headers(nut, &s, NULL))) {
209  av_log(avf, AV_LOG_ERROR, " NUT error: %s\n", nut_error(ret));
210  nut_demuxer_uninit(nut);
211  return -1;
212  }
213 
214  priv->s = s;
215 
216  for (i = 0; s[i].type != -1 && i < 2; i++) {
217  AVStream * st = avformat_new_stream(avf, NULL);
218  int j;
219 
220  for (j = 0; j < s[i].fourcc_len && j < 8; j++) st->codec->codec_tag |= s[i].fourcc[j]<<(j*8);
221 
222  st->codec->has_b_frames = s[i].decode_delay;
223 
224  st->codec->extradata_size = s[i].codec_specific_len;
225  if (st->codec->extradata_size) {
227  memcpy(st->codec->extradata, s[i].codec_specific, st->codec->extradata_size);
228  }
229 
230  avpriv_set_pts_info(avf->streams[i], 60, s[i].time_base.num, s[i].time_base.den);
231  st->start_time = 0;
232  st->duration = s[i].max_pts;
233 
234  st->codec->codec_id = ff_codec_get_id(nut_tags, st->codec->codec_tag);
235 
236  switch(s[i].type) {
237  case NUT_AUDIO_CLASS:
240 
241  st->codec->channels = s[i].channel_count;
242  st->codec->sample_rate = s[i].samplerate_num / s[i].samplerate_denom;
243  break;
244  case NUT_VIDEO_CLASS:
247 
248  st->codec->width = s[i].width;
249  st->codec->height = s[i].height;
250  st->sample_aspect_ratio.num = s[i].sample_width;
251  st->sample_aspect_ratio.den = s[i].sample_height;
252  break;
253  }
254  if (st->codec->codec_id == CODEC_ID_NONE) av_log(avf, AV_LOG_ERROR, "Unknown codec?!\n");
255  }
256 
257  return 0;
258 }
259 
260 static int nut_read_packet(AVFormatContext * avf, AVPacket * pkt) {
261  NUTContext * priv = avf->priv_data;
262  nut_packet_tt pd;
263  int ret;
264 
265  ret = nut_read_next_packet(priv->nut, &pd);
266 
267  if (ret || av_new_packet(pkt, pd.len) < 0) {
268  if (ret != NUT_ERR_EOF)
269  av_log(avf, AV_LOG_ERROR, " NUT error: %s\n", nut_error(ret));
270  return -1;
271  }
272 
273  if (pd.flags & NUT_FLAG_KEY) pkt->flags |= AV_PKT_FLAG_KEY;
274  pkt->pts = pd.pts;
275  pkt->stream_index = pd.stream;
276  pkt->pos = avio_tell(avf->pb);
277 
278  ret = nut_read_frame(priv->nut, &pd.len, pkt->data);
279 
280  return ret;
281 }
282 
283 static int nut_read_seek(AVFormatContext * avf, int stream_index, int64_t target_ts, int flags) {
284  NUTContext * priv = avf->priv_data;
285  int active_streams[] = { stream_index, -1 };
286  double time_pos = target_ts * priv->s[stream_index].time_base.num / (double)priv->s[stream_index].time_base.den;
287 
288  if (nut_seek(priv->nut, time_pos, 2*!(flags & AVSEEK_FLAG_BACKWARD), active_streams)) return -1;
289 
290  return 0;
291 }
292 
294  NUTContext * priv = s->priv_data;
295 
296  nut_demuxer_uninit(priv->nut);
297 
298  return 0;
299 }
300 
302  .name = "libnut",
303  .long_name = NULL_IF_CONFIG_SMALL("NUT format"),
304  .priv_data_size = sizeof(NUTContext),
310  .extensions = "nut",
311 };