thp.c
Go to the documentation of this file.
1 /*
2  * THP Demuxer
3  * Copyright (c) 2007 Marco Gerards
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 
22 #include "libavutil/intreadwrite.h"
23 #include "libavutil/intfloat.h"
24 #include "avformat.h"
25 #include "internal.h"
26 
27 typedef struct ThpDemuxContext {
28  int version;
32  int compoff;
33  int framecnt;
35  int frame;
40  int compcount;
41  unsigned char components[16];
43  int has_audio;
44  int audiosize;
46 
47 
48 static int thp_probe(AVProbeData *p)
49 {
50  /* check file header */
51  if (AV_RL32(p->buf) == MKTAG('T', 'H', 'P', '\0'))
52  return AVPROBE_SCORE_MAX;
53  else
54  return 0;
55 }
56 
58 {
59  ThpDemuxContext *thp = s->priv_data;
60  AVStream *st;
61  AVIOContext *pb = s->pb;
62  int i;
63 
64  /* Read the file header. */
65  avio_rb32(pb); /* Skip Magic. */
66  thp->version = avio_rb32(pb);
67 
68  avio_rb32(pb); /* Max buf size. */
69  avio_rb32(pb); /* Max samples. */
70 
71  thp->fps = av_d2q(av_int2float(avio_rb32(pb)), INT_MAX);
72  thp->framecnt = avio_rb32(pb);
73  thp->first_framesz = avio_rb32(pb);
74  avio_rb32(pb); /* Data size. */
75 
76  thp->compoff = avio_rb32(pb);
77  avio_rb32(pb); /* offsetDataOffset. */
78  thp->first_frame = avio_rb32(pb);
79  thp->last_frame = avio_rb32(pb);
80 
81  thp->next_framesz = thp->first_framesz;
82  thp->next_frame = thp->first_frame;
83 
84  /* Read the component structure. */
85  avio_seek (pb, thp->compoff, SEEK_SET);
86  thp->compcount = avio_rb32(pb);
87 
88  /* Read the list of component types. */
89  avio_read(pb, thp->components, 16);
90 
91  for (i = 0; i < thp->compcount; i++) {
92  if (thp->components[i] == 0) {
93  if (thp->vst != 0)
94  break;
95 
96  /* Video component. */
97  st = avformat_new_stream(s, NULL);
98  if (!st)
99  return AVERROR(ENOMEM);
100 
101  /* The denominator and numerator are switched because 1/fps
102  is required. */
103  avpriv_set_pts_info(st, 64, thp->fps.den, thp->fps.num);
106  st->codec->codec_tag = 0; /* no fourcc */
107  st->codec->width = avio_rb32(pb);
108  st->codec->height = avio_rb32(pb);
109  st->codec->sample_rate = av_q2d(thp->fps);
110  thp->vst = st;
111  thp->video_stream_index = st->index;
112 
113  if (thp->version == 0x11000)
114  avio_rb32(pb); /* Unknown. */
115  } else if (thp->components[i] == 1) {
116  if (thp->has_audio != 0)
117  break;
118 
119  /* Audio component. */
120  st = avformat_new_stream(s, NULL);
121  if (!st)
122  return AVERROR(ENOMEM);
123 
126  st->codec->codec_tag = 0; /* no fourcc */
127  st->codec->channels = avio_rb32(pb); /* numChannels. */
128  st->codec->sample_rate = avio_rb32(pb); /* Frequency. */
129 
130  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
131 
132  thp->audio_stream_index = st->index;
133  thp->has_audio = 1;
134  }
135  }
136 
137  return 0;
138 }
139 
141  AVPacket *pkt)
142 {
143  ThpDemuxContext *thp = s->priv_data;
144  AVIOContext *pb = s->pb;
145  int size;
146  int ret;
147 
148  if (thp->audiosize == 0) {
149  /* Terminate when last frame is reached. */
150  if (thp->frame >= thp->framecnt)
151  return AVERROR(EIO);
152 
153  avio_seek(pb, thp->next_frame, SEEK_SET);
154 
155  /* Locate the next frame and read out its size. */
156  thp->next_frame += thp->next_framesz;
157  thp->next_framesz = avio_rb32(pb);
158 
159  avio_rb32(pb); /* Previous total size. */
160  size = avio_rb32(pb); /* Total size of this frame. */
161 
162  /* Store the audiosize so the next time this function is called,
163  the audio can be read. */
164  if (thp->has_audio)
165  thp->audiosize = avio_rb32(pb); /* Audio size. */
166  else
167  thp->frame++;
168 
169  ret = av_get_packet(pb, pkt, size);
170  if (ret != size) {
171  av_free_packet(pkt);
172  return AVERROR(EIO);
173  }
174 
175  pkt->stream_index = thp->video_stream_index;
176  } else {
177  ret = av_get_packet(pb, pkt, thp->audiosize);
178  if (ret != thp->audiosize) {
179  av_free_packet(pkt);
180  return AVERROR(EIO);
181  }
182 
183  pkt->stream_index = thp->audio_stream_index;
184  if (thp->audiosize >= 8)
185  pkt->duration = AV_RB32(&pkt->data[4]);
186 
187  thp->audiosize = 0;
188  thp->frame++;
189  }
190 
191  return 0;
192 }
193 
195  .name = "thp",
196  .long_name = NULL_IF_CONFIG_SMALL("THP"),
197  .priv_data_size = sizeof(ThpDemuxContext),
201 };