FFmpeg: libavformat/jvdec.c Source File

FFmpeg
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 
28 #include "libavutil/channel_layout.h"
29 #include "libavutil/intreadwrite.h"
30 
31 #include "avformat.h"
32 #include "internal.h"
33 
34  #define JV_PREAMBLE_SIZE 5
35 
36  typedef struct JVFrame {
37   int audio_size; /**< audio packet size (bytes) */
38   int video_size; /**< video packet size (bytes) */
39   uint16_t palette_size; /**< palette size (bytes) */
40   uint8_t video_type; /**< per-frame video compression type */
41 } JVFrame;
42 
43  typedef struct JVDemuxContext {
44   JVFrame *frames;
45  enum {
46   JV_AUDIO = 0,
47   JV_VIDEO,
48   JV_PADDING
49  } state;
50   int64_t pts;
51 } JVDemuxContext;
52 
53  #define MAGIC " Compression by John M Phillips Copyright (C) 1995 The Bitmap Brothers Ltd."
54 
55  static int read_probe(const AVProbeData *pd)
56 {
57  if (pd->buf[0] == 'J' && pd->buf[1] == 'V' && strlen(MAGIC) + 4 <= pd->buf_size &&
58  !memcmp(pd->buf + 4, MAGIC, strlen(MAGIC)))
59  return AVPROBE_SCORE_MAX;
60  return 0;
61 }
62 
63  static int read_close(AVFormatContext *s)
64 {
65  JVDemuxContext *jv = s->priv_data;
66 
67  av_freep(&jv->frames);
68 
69  return 0;
70 }
71 
72  static int read_header(AVFormatContext *s)
73 {
74  JVDemuxContext *jv = s->priv_data;
75  AVIOContext *pb = s->pb;
76  AVStream *vst, *ast;
77  FFStream *asti;
78  int64_t audio_pts = 0;
79  int64_t offset;
80 
81  avio_skip(pb, 80);
82 
83  ast = avformat_new_stream(s, NULL);
84  vst = avformat_new_stream(s, NULL);
85  if (!ast || !vst)
86  return AVERROR(ENOMEM);
87  asti = ffstream(ast);
88 
89  vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
90  vst->codecpar->codec_id = AV_CODEC_ID_JV;
91  vst->codecpar->codec_tag = 0; /* no fourcc */
92  vst->codecpar->width = avio_rl16(pb);
93  vst->codecpar->height = avio_rl16(pb);
94  vst->duration =
95  vst->nb_frames =
96  asti->nb_index_entries = avio_rl16(pb);
97  avpriv_set_pts_info(vst, 64, avio_rl16(pb), 1000);
98 
99  avio_skip(pb, 4);
100 
101  ast->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
102  ast->codecpar->codec_id = AV_CODEC_ID_PCM_U8;
103  ast->codecpar->codec_tag = 0; /* no fourcc */
104  ast->codecpar->sample_rate = avio_rl16(pb);
105  ast->codecpar->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_MONO;
106  avpriv_set_pts_info(ast, 64, 1, ast->codecpar->sample_rate);
107 
108  avio_skip(pb, 10);
109 
110  asti->index_entries = av_malloc(asti->nb_index_entries *
111  sizeof(*asti->index_entries));
112  if (!asti->index_entries)
113  return AVERROR(ENOMEM);
114 
115  jv->frames = av_malloc(asti->nb_index_entries * sizeof(*jv->frames));
116  if (!jv->frames)
117  return AVERROR(ENOMEM);
118  offset = 0x68 + asti->nb_index_entries * 16;
119  for (int i = 0; i < asti->nb_index_entries; i++) {
120  AVIndexEntry *e = asti->index_entries + i;
121  JVFrame *jvf = jv->frames + i;
122 
123  /* total frame size including audio, video, palette data and padding */
124  e->size = avio_rl32(pb);
125  e->timestamp = i;
126  e->pos = offset;
127  offset += e->size;
128 
129  jvf->audio_size = avio_rl32(pb);
130  jvf->video_size = avio_rl32(pb);
131  jvf->palette_size = avio_r8(pb) ? 768 : 0;
132 
133  if ((jvf->video_size | jvf->audio_size) & ~0xFFFFFF ||
134  e->size - jvf->audio_size
135  - jvf->video_size
136  - jvf->palette_size < 0) {
137  if (s->error_recognition & AV_EF_EXPLODE)
138  return AVERROR_INVALIDDATA;
139  jvf->audio_size =
140  jvf->video_size =
141  jvf->palette_size = 0;
142  }
143 
144  if (avio_r8(pb))
145  av_log(s, AV_LOG_WARNING, "unsupported audio codec\n");
146 
147  jvf->video_type = avio_r8(pb);
148  avio_skip(pb, 1);
149 
150  e->timestamp = jvf->audio_size ? audio_pts : AV_NOPTS_VALUE;
151  audio_pts += jvf->audio_size;
152 
153  e->flags = jvf->video_type != 1 ? AVINDEX_KEYFRAME : 0;
154  }
155 
156  jv->state = JV_AUDIO;
157  return 0;
158 }
159 
160  static int read_packet(AVFormatContext *s, AVPacket *pkt)
161 {
162  JVDemuxContext *jv = s->priv_data;
163  AVIOContext *pb = s->pb;
164  AVStream *ast = s->streams[0];
165  FFStream *const asti = ffstream(ast);
166  int ret;
167 
168  while (!avio_feof(s->pb) && jv->pts < asti->nb_index_entries) {
169  const AVIndexEntry *const e = asti->index_entries + jv->pts;
170  const JVFrame *jvf = jv->frames + jv->pts;
171 
172  switch (jv->state) {
173  case JV_AUDIO:
174  jv->state++;
175  if (jvf->audio_size) {
176  if ((ret = av_get_packet(s->pb, pkt, jvf->audio_size)) < 0)
177  return ret;
178  pkt->stream_index = 0;
179  pkt->pts = e->timestamp;
180  pkt->flags |= AV_PKT_FLAG_KEY;
181  return 0;
182  }
183  case JV_VIDEO:
184  jv->state++;
185  if (jvf->video_size || jvf->palette_size) {
186  int size = jvf->video_size + jvf->palette_size;
187  if ((ret = av_new_packet(pkt, size + JV_PREAMBLE_SIZE)) < 0)
188  return ret;
189 
190  AV_WL32(pkt->data, jvf->video_size);
191  pkt->data[4] = jvf->video_type;
192  ret = avio_read(pb, pkt->data + JV_PREAMBLE_SIZE, size);
193  if (ret < 0)
194  return ret;
195  if (ret < size) {
196  memset(pkt->data + JV_PREAMBLE_SIZE + ret, 0,
197  AV_INPUT_BUFFER_PADDING_SIZE);
198  pkt->flags |= AV_PKT_FLAG_CORRUPT;
199  }
200  pkt->size = ret + JV_PREAMBLE_SIZE;
201  pkt->stream_index = 1;
202  pkt->pts = jv->pts;
203  if (jvf->video_type != 1)
204  pkt->flags |= AV_PKT_FLAG_KEY;
205  return 0;
206  }
207  case JV_PADDING:
208  avio_skip(pb, FFMAX(e->size - jvf->audio_size - jvf->video_size
209  - jvf->palette_size, 0));
210  jv->state = JV_AUDIO;
211  jv->pts++;
212  }
213  }
214 
215  if (s->pb->eof_reached)
216  return AVERROR_EOF;
217 
218  return AVERROR(EIO);
219 }
220 
221  static int read_seek(AVFormatContext *s, int stream_index,
222  int64_t ts, int flags)
223 {
224  JVDemuxContext *jv = s->priv_data;
225  AVStream *ast = s->streams[0];
226  FFStream *const asti = ffstream(ast);
227  int i;
228 
229  if (flags & (AVSEEK_FLAG_BYTE | AVSEEK_FLAG_FRAME))
230  return AVERROR(ENOSYS);
231 
232  switch (stream_index) {
233  case 0:
234  i = av_index_search_timestamp(ast, ts, flags);
235  break;
236  case 1:
237  i = ts;
238  break;
239  default:
240  return 0;
241  }
242 
243  if (i < 0 || i >= asti->nb_index_entries)
244  return 0;
245  if (avio_seek(s->pb, asti->index_entries[i].pos, SEEK_SET) < 0)
246  return -1;
247 
248  jv->state = JV_AUDIO;
249  jv->pts = i;
250  return 0;
251 }
252 
253  const AVInputFormat ff_jv_demuxer = {
254  .name = "jv",
255  .long_name = NULL_IF_CONFIG_SMALL("Bitmap Brothers JV"),
256  .priv_data_size = sizeof(JVDemuxContext),
257  .flags_internal = FF_FMT_INIT_CLEANUP,
258  .read_probe = read_probe,
259  .read_header = read_header,
260  .read_packet = read_packet,
261  .read_seek = read_seek,
262  .read_close = read_close,
263 };
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
AV_EF_EXPLODE
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: defs.h:51
FF_FMT_INIT_CLEANUP
#define FF_FMT_INIT_CLEANUP
For an AVInputFormat with this flag set read_close() needs to be called by the caller upon read_heade...
Definition: internal.h:47
AVERROR
Filter the word "frame" indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:243
JVDemuxContext::state
enum JVDemuxContext::@286 state
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:58
AV_WL32
#define AV_WL32(p, v)
Definition: intreadwrite.h:426
AVSEEK_FLAG_FRAME
#define AVSEEK_FLAG_FRAME
seeking based on frame number
Definition: avformat.h:2197
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AVPacket::data
uint8_t * data
Definition: packet.h:374
AVSEEK_FLAG_BYTE
#define AVSEEK_FLAG_BYTE
seeking based on position in bytes
Definition: avformat.h:2195
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:66
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:454
FFMAX
#define FFMAX(a, b)
Definition: macros.h:47
JVFrame
Definition: jvdec.c:36
JVFrame::video_size
int video_size
video packet size (bytes)
Definition: jvdec.c:38
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:429
AVIndexEntry
Definition: avformat.h:697
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:30
AVINDEX_KEYFRAME
#define AVINDEX_KEYFRAME
Definition: avformat.h:705
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
ff_jv_demuxer
const AVInputFormat ff_jv_demuxer
Definition: jvdec.c:253
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:771
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:413
JVDemuxContext::JV_AUDIO
@ JV_AUDIO
Definition: jvdec.c:46
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:897
JVDemuxContext::pts
int64_t pts
Definition: jvdec.c:50
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:735
read_close
static int read_close(AVFormatContext *s)
Definition: jvdec.c:63
pkt
AVPacket * pkt
Definition: movenc.c:59
JVFrame::audio_size
int audio_size
audio packet size (bytes)
Definition: jvdec.c:37
AVInputFormat
Definition: avformat.h:546
AV_PKT_FLAG_CORRUPT
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: packet.h:430
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
av_new_packet
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:97
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:551
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:128
AVIndexEntry::size
int size
Definition: avformat.h:708
AVIndexEntry::timestamp
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:699
JVDemuxContext::JV_PADDING
@ JV_PADDING
Definition: jvdec.c:48
AVFormatContext
Format I/O context.
Definition: avformat.h:1104
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:861
read_packet
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: jvdec.c:160
NULL
#define NULL
Definition: coverity.c:32
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVIndexEntry::flags
int flags
Definition: avformat.h:707
FFStream::nb_index_entries
int nb_index_entries
Definition: internal.h:253
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:213
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:178
AVStream::nb_frames
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:899
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:751
AVIOContext
Bytestream IO Context.
Definition: avio.h:166
AVPacket::size
int size
Definition: packet.h:375
MAGIC
#define MAGIC
Definition: jvdec.c:53
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:115
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:301
FFStream
Definition: internal.h:196
size
int size
Definition: twinvq_data.h:10344
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:624
JVFrame::video_type
uint8_t video_type
per-frame video compression type
Definition: jvdec.c:40
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:380
JV_PREAMBLE_SIZE
#define JV_PREAMBLE_SIZE
Definition: jvdec.c:34
read_header
static int read_header(AVFormatContext *s)
Definition: jvdec.c:72
read_seek
static int read_seek(AVFormatContext *s, int stream_index, int64_t ts, int flags)
Definition: jvdec.c:221
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:367
AVCodecParameters::height
int height
Definition: codec_par.h:129
av_get_packet
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:102
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:838
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:252
avformat.h
AV_CODEC_ID_JV
@ AV_CODEC_ID_JV
Definition: codec_id.h:201
AV_INPUT_BUFFER_PADDING_SIZE
#define AV_INPUT_BUFFER_PADDING_SIZE
Definition: defs.h:40
JVDemuxContext::JV_VIDEO
@ JV_VIDEO
Definition: jvdec.c:47
channel_layout.h
JVFrame::palette_size
uint16_t palette_size
palette size (bytes)
Definition: jvdec.c:39
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
AVIndexEntry::pos
int64_t pos
Definition: avformat.h:698
AVPacket::stream_index
int stream_index
Definition: packet.h:376
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:339
FFStream::index_entries
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: internal.h:251
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AV_CODEC_ID_PCM_U8
@ AV_CODEC_ID_PCM_U8
Definition: codec_id.h:331
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:368
JVDemuxContext::frames
JVFrame * frames
Definition: jvdec.c:44
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:62
AVPacket
This structure stores compressed data.
Definition: packet.h:351
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
JVDemuxContext
Definition: jvdec.c:43
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
av_index_search_timestamp
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: seek.c:240
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:367
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