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 "internal.h"
27 #include "avio_internal.h"
28 #include "rawdec.h"
29 #include "libavutil/opt.h"
30 #include "libavutil/parseutils.h"
31 #include "libavutil/pixdesc.h"
32 #include "libavutil/intreadwrite.h"
33 
34 #define RAW_PACKET_SIZE 1024
35 
36 int ff_raw_read_partial_packet(AVFormatContext *s, AVPacket *pkt)
37 {
38  FFRawDemuxerContext *raw = s->priv_data;
39  int ret, size;
40 
41  size = raw->raw_packet_size;
42 
43  if ((ret = av_new_packet(pkt, size)) < 0)
44  return ret;
45 
46  pkt->pos= avio_tell(s->pb);
47  pkt->stream_index = 0;
48  ret = avio_read_partial(s->pb, pkt->data, size);
49  if (ret < 0) {
50  av_packet_unref(pkt);
51  return ret;
52  }
53  av_shrink_packet(pkt, ret);
54  return ret;
55 }
56 
57 int ff_raw_audio_read_header(AVFormatContext *s)
58 {
59  AVStream *st = avformat_new_stream(s, NULL);
60  if (!st)
61  return AVERROR(ENOMEM);
62  st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
63  st->codecpar->codec_id = s->iformat->raw_codec_id;
64  ffstream(st)->need_parsing = AVSTREAM_PARSE_FULL_RAW;
65  st->start_time = 0;
66  /* the parameters will be extracted from the compressed bitstream */
67 
68  return 0;
69 }
70 
71 /* MPEG-1/H.263 input */
72 int ff_raw_video_read_header(AVFormatContext *s)
73 {
74  AVStream *st;
75  FFStream *sti;
76  FFRawVideoDemuxerContext *s1 = s->priv_data;
77  int ret = 0;
78 
79 
80  st = avformat_new_stream(s, NULL);
81  if (!st) {
82  ret = AVERROR(ENOMEM);
83  goto fail;
84  }
85  sti = ffstream(st);
86 
87  st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
88  st->codecpar->codec_id = s->iformat->raw_codec_id;
89  sti->need_parsing = AVSTREAM_PARSE_FULL_RAW;
90 
91  sti->avctx->framerate = s1->framerate;
92  avpriv_set_pts_info(st, 64, 1, 1200000);
93 
94 fail:
95  return ret;
96 }
97 
98 int ff_raw_subtitle_read_header(AVFormatContext *s)
99 {
100  AVStream *st = avformat_new_stream(s, NULL);
101  if (!st)
102  return AVERROR(ENOMEM);
103  st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
104  st->codecpar->codec_id = s->iformat->raw_codec_id;
105  st->start_time = 0;
106  return 0;
107 }
108 
109 static int raw_data_read_header(AVFormatContext *s)
110 {
111  AVStream *st = avformat_new_stream(s, NULL);
112  if (!st)
113  return AVERROR(ENOMEM);
114  st->codecpar->codec_type = AVMEDIA_TYPE_DATA;
115  st->codecpar->codec_id = s->iformat->raw_codec_id;
116  st->start_time = 0;
117  return 0;
118 }
119 
120 /* Note: Do not forget to add new entries to the Makefile as well. */
121 
122 #define OFFSET(x) offsetof(FFRawVideoDemuxerContext, x)
123 #define DEC AV_OPT_FLAG_DECODING_PARAM
124 static const AVOption rawvideo_options[] = {
125  { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, DEC},
126  { "raw_packet_size", "", OFFSET(raw_packet_size), AV_OPT_TYPE_INT, {.i64 = RAW_PACKET_SIZE }, 1, INT_MAX, DEC},
127  { NULL },
128 };
129 #undef OFFSET
130 
131 const AVClass ff_rawvideo_demuxer_class = {
132  .class_name = "generic raw video demuxer",
133  .item_name = av_default_item_name,
134  .option = rawvideo_options,
135  .version = LIBAVUTIL_VERSION_INT,
136 };
137 
138 #define OFFSET(x) offsetof(FFRawDemuxerContext, x)
139 static const AVOption raw_options[] = {
140  { "raw_packet_size", "", OFFSET(raw_packet_size), AV_OPT_TYPE_INT, {.i64 = RAW_PACKET_SIZE }, 1, INT_MAX, DEC},
141  { NULL },
142 };
143 
144 const AVClass ff_raw_demuxer_class = {
145  .class_name = "generic raw demuxer",
146  .item_name = av_default_item_name,
147  .option = raw_options,
148  .version = LIBAVUTIL_VERSION_INT,
149 };
150 
151 #if CONFIG_DATA_DEMUXER
152 const AVInputFormat ff_data_demuxer = {
153  .name = "data",
154  .long_name = NULL_IF_CONFIG_SMALL("raw data"),
155  .read_header = raw_data_read_header,
156  .read_packet = ff_raw_read_partial_packet,
157  .raw_codec_id = AV_CODEC_ID_NONE,
158  .flags = AVFMT_NOTIMESTAMPS,
159  .priv_data_size = sizeof(FFRawDemuxerContext),\
160  .priv_class = &ff_raw_demuxer_class,
161 };
162 #endif
163 
164 #if CONFIG_MJPEG_DEMUXER
165 static int mjpeg_probe(const AVProbeData *p)
166 {
167  int i;
168  int state = -1;
169  int nb_invalid = 0;
170  int nb_frames = 0;
171 
172  for (i = 0; i < p->buf_size - 1; i++) {
173  int c;
174  if (p->buf[i] != 0xFF)
175  continue;
176  c = p->buf[i+1];
177  switch (c) {
178  case 0xD8:
179  state = 0xD8;
180  break;
181  case 0xC0:
182  case 0xC1:
183  case 0xC2:
184  case 0xC3:
185  case 0xC5:
186  case 0xC6:
187  case 0xC7:
188  case 0xF7:
189  if (state == 0xD8) {
190  state = 0xC0;
191  } else
192  nb_invalid++;
193  break;
194  case 0xDA:
195  if (state == 0xC0) {
196  state = 0xDA;
197  } else
198  nb_invalid++;
199  break;
200  case 0xD9:
201  if (state == 0xDA) {
202  state = 0xD9;
203  nb_frames++;
204  } else
205  nb_invalid++;
206  break;
207  default:
208  if ( (c >= 0x02 && c <= 0xBF)
209  || c == 0xC8) {
210  nb_invalid++;
211  }
212  }
213  }
214 
215  if (nb_invalid*4 + 1 < nb_frames) {
216  static const char ct_jpeg[] = "\r\nContent-Type: image/jpeg\r\n";
217  int i;
218 
219  for (i=0; i<FFMIN(p->buf_size - (int)sizeof(ct_jpeg), 100); i++)
220  if (!memcmp(p->buf + i, ct_jpeg, sizeof(ct_jpeg) - 1))
221  return AVPROBE_SCORE_EXTENSION;
222 
223  if (nb_invalid == 0 && nb_frames > 2)
224  return AVPROBE_SCORE_EXTENSION / 2;
225  return AVPROBE_SCORE_EXTENSION / 4;
226  }
227  if (!nb_invalid && nb_frames)
228  return AVPROBE_SCORE_EXTENSION / 4;
229 
230  return 0;
231 }
232 
233 FF_DEF_RAWVIDEO_DEMUXER2(mjpeg, "raw MJPEG video", mjpeg_probe, "mjpg,mjpeg,mpo", AV_CODEC_ID_MJPEG, AVFMT_GENERIC_INDEX|AVFMT_NOTIMESTAMPS)
234 #endif
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:422
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:72
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:237
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:57
ff_rawvideo_demuxer_class
const AVClass ff_rawvideo_demuxer_class
Definition: rawdec.c:131
raw_options
static const AVOption raw_options[]
Definition: rawdec.c:139
AV_OPT_TYPE_VIDEO_RATE
@ AV_OPT_TYPE_VIDEO_RATE
offset must point to AVRational
Definition: opt.h:238
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:481
pixdesc.h
AVPacket::data
uint8_t * data
Definition: packet.h:374
AVOption
AVOption.
Definition: opt.h:251
ff_raw_subtitle_read_header
int ff_raw_subtitle_read_header(AVFormatContext *s)
Definition: rawdec.c:98
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:456
AVCodecContext::framerate
AVRational framerate
Definition: avcodec.h:1732
framerate
int framerate
Definition: h264_levels.c:65
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:697
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:407
fail
#define fail()
Definition: checkasm.h:131
av_shrink_packet
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: avpacket.c:112
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:505
FFRawDemuxerContext
Definition: rawdec.h:36
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:482
rawvideo_options
static const AVOption rawvideo_options[]
Definition: rawdec.c:124
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:656
ff_raw_read_partial_packet
int ff_raw_read_partial_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawdec.c:36
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:661
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:455
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:38
AVMEDIA_TYPE_DATA
@ AVMEDIA_TYPE_DATA
Opaque data information usually continuous.
Definition: avutil.h:203
ff_data_demuxer
const AVInputFormat ff_data_demuxer
FFStream::need_parsing
enum AVStreamParseType need_parsing
Definition: internal.h:380
ff_raw_demuxer_class
const AVClass ff_raw_demuxer_class
Definition: rawdec.c:144
AVFormatContext
Format I/O context.
Definition: avformat.h:1213
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1108
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
parseutils.h
ff_raw_audio_read_header
int ff_raw_audio_read_header(AVFormatContext *s)
Definition: rawdec.c:57
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:453
RAW_PACKET_SIZE
#define RAW_PACKET_SIZE
Definition: rawdec.c:34
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:463
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:117
FFStream
Definition: internal.h:197
size
int size
Definition: twinvq_data.h:10344
state
static struct @327 state
FFRawVideoDemuxerContext
Definition: rawdec.h:28
OFFSET
#define OFFSET(x)
Definition: rawdec.c:138
AV_CODEC_ID_MJPEG
@ AV_CODEC_ID_MJPEG
Definition: codec_id.h:57
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:48
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
avio_internal.h
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
raw_data_read_header
static int raw_data_read_header(AVFormatContext *s)
Definition: rawdec.c:109
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:948
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
FFStream::avctx
AVCodecContext * avctx
The codec context used by avformat_find_stream_info, the parser, etc.
Definition: internal.h:224
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:225
FF_DEF_RAWVIDEO_DEMUXER2
#define FF_DEF_RAWVIDEO_DEMUXER2(shortname, longname, probe, ext, id, flag)
Definition: rawdec.h:52
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:802
AVPacket::stream_index
int stream_index
Definition: packet.h:376
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
DEC
#define DEC
Definition: rawdec.c:123
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:61
AVPacket
This structure stores compressed data.
Definition: packet.h:351
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:394
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:988
avio_read_partial
int avio_read_partial(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:713
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