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jvdec.c
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1 /*
2  * Bitmap Brothers JV demuxer
3  * Copyright (c) 2005, 2011 Peter Ross <pross@xvid.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  * Bitmap Brothers JV demuxer
25  * @author Peter Ross <pross@xvid.org>
26  */
27 
29 #include "libavutil/intreadwrite.h"
30 #include "avformat.h"
31 #include "internal.h"
32 
33 #define JV_PREAMBLE_SIZE 5
34 
35 typedef struct {
36  int audio_size; /**< audio packet size (bytes) */
37  int video_size; /**< video packet size (bytes) */
38  int palette_size; /**< palette size (bytes) */
39  int video_type; /**< per-frame video compression type */
40 } JVFrame;
41 
42 typedef struct {
44  enum {
45  JV_AUDIO = 0,
47  JV_PADDING
48  } state;
49  int64_t pts;
51 
52 #define MAGIC " Compression by John M Phillips Copyright (C) 1995 The Bitmap Brothers Ltd."
53 
54 static int read_probe(AVProbeData *pd)
55 {
56  if (pd->buf[0] == 'J' && pd->buf[1] == 'V' && strlen(MAGIC) <= pd->buf_size - 4 &&
57  !memcmp(pd->buf + 4, MAGIC, strlen(MAGIC)))
58  return AVPROBE_SCORE_MAX;
59  return 0;
60 }
61 
63 {
64  JVDemuxContext *jv = s->priv_data;
65  AVIOContext *pb = s->pb;
66  AVStream *vst, *ast;
67  int64_t audio_pts = 0;
68  int64_t offset;
69  int i;
70 
71  avio_skip(pb, 80);
72 
73  ast = avformat_new_stream(s, NULL);
74  vst = avformat_new_stream(s, NULL);
75  if (!ast || !vst)
76  return AVERROR(ENOMEM);
77 
80  vst->codec->codec_tag = 0; /* no fourcc */
81  vst->codec->width = avio_rl16(pb);
82  vst->codec->height = avio_rl16(pb);
83  vst->duration =
84  vst->nb_frames =
85  ast->nb_index_entries = avio_rl16(pb);
86  avpriv_set_pts_info(vst, 64, avio_rl16(pb), 1000);
87 
88  avio_skip(pb, 4);
89 
92  ast->codec->codec_tag = 0; /* no fourcc */
93  ast->codec->sample_rate = avio_rl16(pb);
94  ast->codec->channels = 1;
96  avpriv_set_pts_info(ast, 64, 1, ast->codec->sample_rate);
97 
98  avio_skip(pb, 10);
99 
100  ast->index_entries = av_malloc(ast->nb_index_entries * sizeof(*ast->index_entries));
101  if (!ast->index_entries)
102  return AVERROR(ENOMEM);
103 
104  jv->frames = av_malloc(ast->nb_index_entries * sizeof(JVFrame));
105  if (!jv->frames)
106  return AVERROR(ENOMEM);
107 
108  offset = 0x68 + ast->nb_index_entries * 16;
109  for(i = 0; i < ast->nb_index_entries; i++) {
110  AVIndexEntry *e = ast->index_entries + i;
111  JVFrame *jvf = jv->frames + i;
112 
113  /* total frame size including audio, video, palette data and padding */
114  e->size = avio_rl32(pb);
115  e->timestamp = i;
116  e->pos = offset;
117  offset += e->size;
118 
119  jvf->audio_size = avio_rl32(pb);
120  jvf->video_size = avio_rl32(pb);
121  jvf->palette_size = avio_r8(pb) ? 768 : 0;
122  jvf->video_size = FFMIN(FFMAX(jvf->video_size, 0),
123  INT_MAX - JV_PREAMBLE_SIZE - jvf->palette_size);
124  if (avio_r8(pb))
125  av_log(s, AV_LOG_WARNING, "unsupported audio codec\n");
126  jvf->video_type = avio_r8(pb);
127  avio_skip(pb, 1);
128 
129  e->timestamp = jvf->audio_size ? audio_pts : AV_NOPTS_VALUE;
130  audio_pts += jvf->audio_size;
131 
132  e->flags = jvf->video_type != 1 ? AVINDEX_KEYFRAME : 0;
133  }
134 
135  jv->state = JV_AUDIO;
136  return 0;
137 }
138 
140 {
141  JVDemuxContext *jv = s->priv_data;
142  AVIOContext *pb = s->pb;
143  AVStream *ast = s->streams[0];
144 
145  while (!url_feof(s->pb) && jv->pts < ast->nb_index_entries) {
146  const AVIndexEntry *e = ast->index_entries + jv->pts;
147  const JVFrame *jvf = jv->frames + jv->pts;
148 
149  switch(jv->state) {
150  case JV_AUDIO:
151  jv->state++;
152  if (jvf->audio_size ) {
153  if (av_get_packet(s->pb, pkt, jvf->audio_size) < 0)
154  return AVERROR(ENOMEM);
155  pkt->stream_index = 0;
156  pkt->pts = e->timestamp;
157  pkt->flags |= AV_PKT_FLAG_KEY;
158  return 0;
159  }
160  case JV_VIDEO:
161  jv->state++;
162  if (jvf->video_size || jvf->palette_size) {
163  int size = jvf->video_size + jvf->palette_size;
164  if (av_new_packet(pkt, size + JV_PREAMBLE_SIZE))
165  return AVERROR(ENOMEM);
166 
167  AV_WL32(pkt->data, jvf->video_size);
168  pkt->data[4] = jvf->video_type;
169  if ((size = avio_read(pb, pkt->data + JV_PREAMBLE_SIZE, size)) < 0)
170  return AVERROR(EIO);
171 
172  pkt->size = size + JV_PREAMBLE_SIZE;
173  pkt->stream_index = 1;
174  pkt->pts = jv->pts;
175  if (jvf->video_type != 1)
176  pkt->flags |= AV_PKT_FLAG_KEY;
177  return 0;
178  }
179  case JV_PADDING:
180  avio_skip(pb, FFMAX(e->size - jvf->audio_size - jvf->video_size
181  - jvf->palette_size, 0));
182  jv->state = JV_AUDIO;
183  jv->pts++;
184  }
185  }
186 
187  return AVERROR(EIO);
188 }
189 
190 static int read_seek(AVFormatContext *s, int stream_index,
191  int64_t ts, int flags)
192 {
193  JVDemuxContext *jv = s->priv_data;
194  AVStream *ast = s->streams[0];
195  int i;
196 
197  if (flags & (AVSEEK_FLAG_BYTE|AVSEEK_FLAG_FRAME))
198  return AVERROR(ENOSYS);
199 
200  switch(stream_index) {
201  case 0:
202  i = av_index_search_timestamp(ast, ts, flags);
203  break;
204  case 1:
205  i = ts;
206  break;
207  default:
208  return 0;
209  }
210 
211  if (i < 0 || i >= ast->nb_index_entries)
212  return 0;
213  if (avio_seek(s->pb, ast->index_entries[i].pos, SEEK_SET) < 0)
214  return -1;
215 
216  jv->state = JV_AUDIO;
217  jv->pts = i;
218  return 0;
219 }
220 
222 {
223  JVDemuxContext *jv = s->priv_data;
224 
225  av_freep(&jv->frames);
226 
227  return 0;
228 }
229 
231  .name = "jv",
232  .long_name = NULL_IF_CONFIG_SMALL("Bitmap Brothers JV"),
233  .priv_data_size = sizeof(JVDemuxContext),
237  .read_seek = read_seek,
239 };