FFmpeg
rawdec.c
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1 /*
2  * RAW demuxers
3  * Copyright (c) 2001 Fabrice Bellard
4  * Copyright (c) 2005 Alex Beregszaszi
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "config_components.h"
24 
25 #include "avformat.h"
26 #include "demux.h"
27 #include "internal.h"
28 #include "rawdec.h"
29 #include "libavutil/opt.h"
30 
31 #define RAW_PACKET_SIZE 1024
32 
34 {
35  FFRawDemuxerContext *raw = s->priv_data;
36  int ret, size;
37 
38  size = raw->raw_packet_size;
39 
40  if ((ret = av_new_packet(pkt, size)) < 0)
41  return ret;
42 
43  pkt->pos= avio_tell(s->pb);
44  pkt->stream_index = 0;
45  ret = avio_read_partial(s->pb, pkt->data, size);
46  if (ret < 0) {
48  return ret;
49  }
51  return ret;
52 }
53 
55 {
57  if (!st)
58  return AVERROR(ENOMEM);
60  st->codecpar->codec_id = ffifmt(s->iformat)->raw_codec_id;
62  st->start_time = 0;
63  /* the parameters will be extracted from the compressed bitstream */
64 
65  return 0;
66 }
67 
68 /* MPEG-1/H.263 input */
70 {
71  AVStream *st;
72  FFStream *sti;
73  FFRawVideoDemuxerContext *s1 = s->priv_data;
74  int ret = 0;
75 
76 
77  st = avformat_new_stream(s, NULL);
78  if (!st) {
79  ret = AVERROR(ENOMEM);
80  goto fail;
81  }
82  sti = ffstream(st);
83 
85  st->codecpar->codec_id = ffifmt(s->iformat)->raw_codec_id;
87 
88  st->avg_frame_rate = s1->framerate;
89  avpriv_set_pts_info(st, 64, 1, 1200000);
90 
91 fail:
92  return ret;
93 }
94 
96 {
98  if (!st)
99  return AVERROR(ENOMEM);
101  st->codecpar->codec_id = ffifmt(s->iformat)->raw_codec_id;
102  st->start_time = 0;
103  return 0;
104 }
105 
107 {
109  if (!st)
110  return AVERROR(ENOMEM);
112  st->codecpar->codec_id = ffifmt(s->iformat)->raw_codec_id;
113  st->start_time = 0;
114  return 0;
115 }
116 
117 /* Note: Do not forget to add new entries to the Makefile as well. */
118 
119 #define OFFSET(x) offsetof(FFRawVideoDemuxerContext, x)
120 #define DEC AV_OPT_FLAG_DECODING_PARAM
121 static const AVOption rawvideo_options[] = {
122  { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, DEC},
123  { "raw_packet_size", "", OFFSET(raw_packet_size), AV_OPT_TYPE_INT, {.i64 = RAW_PACKET_SIZE }, 1, INT_MAX, DEC},
124  { NULL },
125 };
126 #undef OFFSET
127 
129  .class_name = "generic raw video demuxer",
130  .item_name = av_default_item_name,
131  .option = rawvideo_options,
132  .version = LIBAVUTIL_VERSION_INT,
133 };
134 
135 #define OFFSET(x) offsetof(FFRawDemuxerContext, x)
136 static const AVOption raw_options[] = {
137  { "raw_packet_size", "", OFFSET(raw_packet_size), AV_OPT_TYPE_INT, {.i64 = RAW_PACKET_SIZE }, 1, INT_MAX, DEC},
138  { NULL },
139 };
140 
142  .class_name = "generic raw demuxer",
143  .item_name = av_default_item_name,
144  .option = raw_options,
145  .version = LIBAVUTIL_VERSION_INT,
146 };
147 
148 #if CONFIG_DATA_DEMUXER
150  .p.name = "data",
151  .p.long_name = NULL_IF_CONFIG_SMALL("raw data"),
152  .p.flags = AVFMT_NOTIMESTAMPS,
153  .p.priv_class = &ff_raw_demuxer_class,
154  .read_header = raw_data_read_header,
155  .read_packet = ff_raw_read_partial_packet,
156  .raw_codec_id = AV_CODEC_ID_NONE,
157  .priv_data_size = sizeof(FFRawDemuxerContext),\
158 };
159 #endif
160 
161 #if CONFIG_MJPEG_DEMUXER
162 static int mjpeg_probe(const AVProbeData *p)
163 {
164  int i;
165  int state = -1;
166  int nb_invalid = 0;
167  int nb_frames = 0;
168 
169  for (i = 0; i < p->buf_size - 1; i++) {
170  int c;
171  if (p->buf[i] != 0xFF)
172  continue;
173  c = p->buf[i+1];
174  switch (c) {
175  case 0xD8:
176  state = 0xD8;
177  break;
178  case 0xC0:
179  case 0xC1:
180  case 0xC2:
181  case 0xC3:
182  case 0xC5:
183  case 0xC6:
184  case 0xC7:
185  case 0xF7:
186  if (state == 0xD8) {
187  state = 0xC0;
188  } else
189  nb_invalid++;
190  break;
191  case 0xDA:
192  if (state == 0xC0) {
193  state = 0xDA;
194  } else
195  nb_invalid++;
196  break;
197  case 0xD9:
198  if (state == 0xDA) {
199  state = 0xD9;
200  nb_frames++;
201  } else
202  nb_invalid++;
203  break;
204  default:
205  if ( (c >= 0x02 && c <= 0xBF)
206  || c == 0xC8) {
207  nb_invalid++;
208  }
209  }
210  }
211 
212  if (nb_invalid*4 + 1 < nb_frames) {
213  static const char ct_jpeg[] = "\r\nContent-Type: image/jpeg\r\n";
214  int i;
215 
216  for (i=0; i<FFMIN(p->buf_size - (int)sizeof(ct_jpeg), 100); i++)
217  if (!memcmp(p->buf + i, ct_jpeg, sizeof(ct_jpeg) - 1))
219 
220  if (nb_invalid == 0 && nb_frames > 2)
221  return AVPROBE_SCORE_EXTENSION / 2;
222  return AVPROBE_SCORE_EXTENSION / 4;
223  }
224  if (!nb_invalid && nb_frames)
225  return AVPROBE_SCORE_EXTENSION / 4;
226 
227  return 0;
228 }
229 
230 FF_DEF_RAWVIDEO_DEMUXER2(mjpeg, "raw MJPEG video", mjpeg_probe, "mjpg,mjpeg,mpo", AV_CODEC_ID_MJPEG, AVFMT_GENERIC_INDEX|AVFMT_NOTIMESTAMPS)
231 #endif
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: packet.c:427
AVMEDIA_TYPE_SUBTITLE
@ AVMEDIA_TYPE_SUBTITLE
Definition: avutil.h:204
ff_raw_video_read_header
int ff_raw_video_read_header(AVFormatContext *s)
Definition: rawdec.c:69
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
opt.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
ff_rawvideo_demuxer_class
const AVClass ff_rawvideo_demuxer_class
Definition: rawdec.c:128
raw_options
static const AVOption raw_options[]
Definition: rawdec.c:136
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AV_OPT_TYPE_VIDEO_RATE
@ AV_OPT_TYPE_VIDEO_RATE
offset must point to AVRational
Definition: opt.h:248
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:479
AVPacket::data
uint8_t * data
Definition: packet.h:524
AVOption
AVOption.
Definition: opt.h:346
AVStream::avg_frame_rate
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:832
ff_raw_subtitle_read_header
int ff_raw_subtitle_read_header(AVFormatContext *s)
Definition: rawdec.c:95
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:454
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:853
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:417
fail
#define fail()
Definition: checkasm.h:179
av_shrink_packet
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: packet.c:113
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:494
FFRawDemuxerContext
Definition: rawdec.h:37
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:480
rawvideo_options
static const AVOption rawvideo_options[]
Definition: rawdec.c:121
pkt
AVPacket * pkt
Definition: movenc.c:60
ff_raw_read_partial_packet
int ff_raw_read_partial_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawdec.c:33
s
#define s(width, name)
Definition: cbs_vp9.c:198
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: packet.c:98
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:553
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
s1
#define s1
Definition: regdef.h:38
FFRawDemuxerContext::raw_packet_size
int raw_packet_size
Definition: rawdec.h:39
AVMEDIA_TYPE_DATA
@ AVMEDIA_TYPE_DATA
Opaque data information usually continuous.
Definition: avutil.h:203
FFStream::need_parsing
enum AVStreamParseType need_parsing
Definition: internal.h:386
ff_raw_demuxer_class
const AVClass ff_raw_demuxer_class
Definition: rawdec.c:141
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:766
framerate
float framerate
Definition: av1_levels.c:29
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
rawdec.h
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
ff_raw_audio_read_header
int ff_raw_audio_read_header(AVFormatContext *s)
Definition: rawdec.c:54
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
RAW_PACKET_SIZE
#define RAW_PACKET_SIZE
Definition: rawdec.c:31
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:461
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:94
FFStream
Definition: internal.h:193
size
int size
Definition: twinvq_data.h:10344
state
static struct @395 state
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:41
FFRawVideoDemuxerContext
Definition: rawdec.h:29
OFFSET
#define OFFSET(x)
Definition: rawdec.c:135
AV_CODEC_ID_MJPEG
@ AV_CODEC_ID_MJPEG
Definition: codec_id.h:59
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
FFInputFormat::raw_codec_id
enum AVCodecID raw_codec_id
Raw demuxers store their codec ID here.
Definition: demux.h:46
demux.h
raw_data_read_header
static int raw_data_read_header(AVFormatContext *s)
Definition: rawdec.c:106
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:743
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:71
avformat.h
ffifmt
static const FFInputFormat * ffifmt(const AVInputFormat *fmt)
Definition: demux.h:133
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:235
FF_DEF_RAWVIDEO_DEMUXER2
#define FF_DEF_RAWVIDEO_DEMUXER2(shortname, longname, probe, ext, id, flag)
Definition: rawdec.h:53
AVSTREAM_PARSE_FULL_RAW
@ AVSTREAM_PARSE_FULL_RAW
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:597
AVPacket::stream_index
int stream_index
Definition: packet.h:526
ff_data_demuxer
const FFInputFormat ff_data_demuxer
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
DEC
#define DEC
Definition: rawdec.c:120
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:501
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:544
FFInputFormat
Definition: demux.h:37
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:792
avio_read_partial
int avio_read_partial(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:684