thp.c
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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 
59 {
60  ThpDemuxContext *thp = s->priv_data;
61  AVStream *st;
62  AVIOContext *pb = s->pb;
63  int i;
64 
65  /* Read the file header. */
66  avio_rb32(pb); /* Skip Magic. */
67  thp->version = avio_rb32(pb);
68 
69  avio_rb32(pb); /* Max buf size. */
70  avio_rb32(pb); /* Max samples. */
71 
72  thp->fps = av_d2q(av_int2float(avio_rb32(pb)), INT_MAX);
73  thp->framecnt = avio_rb32(pb);
74  thp->first_framesz = avio_rb32(pb);
75  avio_rb32(pb); /* Data size. */
76 
77  thp->compoff = avio_rb32(pb);
78  avio_rb32(pb); /* offsetDataOffset. */
79  thp->first_frame = avio_rb32(pb);
80  thp->last_frame = avio_rb32(pb);
81 
82  thp->next_framesz = thp->first_framesz;
83  thp->next_frame = thp->first_frame;
84 
85  /* Read the component structure. */
86  avio_seek (pb, thp->compoff, SEEK_SET);
87  thp->compcount = avio_rb32(pb);
88 
89  /* Read the list of component types. */
90  avio_read(pb, thp->components, 16);
91 
92  for (i = 0; i < thp->compcount; i++) {
93  if (thp->components[i] == 0) {
94  if (thp->vst != 0)
95  break;
96 
97  /* Video component. */
98  st = avformat_new_stream(s, NULL);
99  if (!st)
100  return AVERROR(ENOMEM);
101 
102  /* The denominator and numerator are switched because 1/fps
103  is required. */
104  avpriv_set_pts_info(st, 64, thp->fps.den, thp->fps.num);
106  st->codec->codec_id = CODEC_ID_THP;
107  st->codec->codec_tag = 0; /* no fourcc */
108  st->codec->width = avio_rb32(pb);
109  st->codec->height = avio_rb32(pb);
110  st->codec->sample_rate = av_q2d(thp->fps);
111  thp->vst = st;
112  thp->video_stream_index = st->index;
113 
114  if (thp->version == 0x11000)
115  avio_rb32(pb); /* Unknown. */
116  } else if (thp->components[i] == 1) {
117  if (thp->has_audio != 0)
118  break;
119 
120  /* Audio component. */
121  st = avformat_new_stream(s, NULL);
122  if (!st)
123  return AVERROR(ENOMEM);
124 
127  st->codec->codec_tag = 0; /* no fourcc */
128  st->codec->channels = avio_rb32(pb); /* numChannels. */
129  st->codec->sample_rate = avio_rb32(pb); /* Frequency. */
130 
131  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
132 
133  thp->audio_stream_index = st->index;
134  thp->has_audio = 1;
135  }
136  }
137 
138  return 0;
139 }
140 
142  AVPacket *pkt)
143 {
144  ThpDemuxContext *thp = s->priv_data;
145  AVIOContext *pb = s->pb;
146  int size;
147  int ret;
148 
149  if (thp->audiosize == 0) {
150  /* Terminate when last frame is reached. */
151  if (thp->frame >= thp->framecnt)
152  return AVERROR(EIO);
153 
154  avio_seek(pb, thp->next_frame, SEEK_SET);
155 
156  /* Locate the next frame and read out its size. */
157  thp->next_frame += thp->next_framesz;
158  thp->next_framesz = avio_rb32(pb);
159 
160  avio_rb32(pb); /* Previous total size. */
161  size = avio_rb32(pb); /* Total size of this frame. */
162 
163  /* Store the audiosize so the next time this function is called,
164  the audio can be read. */
165  if (thp->has_audio)
166  thp->audiosize = avio_rb32(pb); /* Audio size. */
167  else
168  thp->frame++;
169 
170  ret = av_get_packet(pb, pkt, size);
171  if (ret != size) {
172  av_free_packet(pkt);
173  return AVERROR(EIO);
174  }
175 
176  pkt->stream_index = thp->video_stream_index;
177  } else {
178  ret = av_get_packet(pb, pkt, thp->audiosize);
179  if (ret != thp->audiosize) {
180  av_free_packet(pkt);
181  return AVERROR(EIO);
182  }
183 
184  pkt->stream_index = thp->audio_stream_index;
185  thp->audiosize = 0;
186  thp->frame++;
187  }
188 
189  return 0;
190 }
191 
193  .name = "thp",
194  .long_name = NULL_IF_CONFIG_SMALL("THP"),
195  .priv_data_size = sizeof(ThpDemuxContext),
199 };