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 "avformat.h"
24 #include "internal.h"
25 #include "avio_internal.h"
26 #include "rawdec.h"
27 #include "libavutil/opt.h"
28 #include "libavutil/parseutils.h"
29 #include "libavutil/pixdesc.h"
30 #include "libavutil/avassert.h"
31 #include "libavutil/intreadwrite.h"
32 
33 #define RAW_PACKET_SIZE 1024
34 
36 {
38  int ret, size;
39 
40  size = raw->raw_packet_size;
41 
42  if (av_new_packet(pkt, size) < 0)
43  return AVERROR(ENOMEM);
44 
45  pkt->pos= avio_tell(s->pb);
46  pkt->stream_index = 0;
47  ret = avio_read_partial(s->pb, pkt->data, size);
48  if (ret < 0) {
49  av_packet_unref(pkt);
50  return ret;
51  }
52  av_shrink_packet(pkt, ret);
53  return ret;
54 }
55 
57 {
59  if (!st)
60  return AVERROR(ENOMEM);
64  st->start_time = 0;
65  /* the parameters will be extracted from the compressed bitstream */
66 
67  return 0;
68 }
69 
70 /* MPEG-1/H.263 input */
72 {
73  AVStream *st;
75  int ret = 0;
76 
77 
78  st = avformat_new_stream(s, NULL);
79  if (!st) {
80  ret = AVERROR(ENOMEM);
81  goto fail;
82  }
83 
87 
88  st->internal->avctx->framerate = 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);
102  st->start_time = 0;
103  return 0;
104 }
105 
107 {
109  if (!st)
110  return AVERROR(ENOMEM);
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
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 };
127  { "raw_packet_size", "", OFFSET(raw_packet_size), AV_OPT_TYPE_INT, {.i64 = RAW_PACKET_SIZE }, 1, INT_MAX, DEC},
128  { NULL },
129 };
130 
131 #if CONFIG_DATA_DEMUXER
132 FF_RAW_DEMUXER_CLASS(raw_data)
133 
135  .name = "data",
136  .long_name = NULL_IF_CONFIG_SMALL("raw data"),
137  .read_header = ff_raw_data_read_header,
138  .read_packet = ff_raw_read_partial_packet,
139  .raw_codec_id = AV_CODEC_ID_NONE,
140  .flags = AVFMT_NOTIMESTAMPS,
141  .priv_data_size = sizeof(FFRawDemuxerContext),\
142  .priv_class = &raw_data_demuxer_class,\
143 };
144 #endif
145 
146 #if CONFIG_MJPEG_DEMUXER
147 static int mjpeg_probe(const AVProbeData *p)
148 {
149  int i;
150  int state = -1;
151  int nb_invalid = 0;
152  int nb_frames = 0;
153 
154  for (i = 0; i < p->buf_size - 1; i++) {
155  int c;
156  if (p->buf[i] != 0xFF)
157  continue;
158  c = p->buf[i+1];
159  switch (c) {
160  case 0xD8:
161  state = 0xD8;
162  break;
163  case 0xC0:
164  case 0xC1:
165  case 0xC2:
166  case 0xC3:
167  case 0xC5:
168  case 0xC6:
169  case 0xC7:
170  case 0xF7:
171  if (state == 0xD8) {
172  state = 0xC0;
173  } else
174  nb_invalid++;
175  break;
176  case 0xDA:
177  if (state == 0xC0) {
178  state = 0xDA;
179  } else
180  nb_invalid++;
181  break;
182  case 0xD9:
183  if (state == 0xDA) {
184  state = 0xD9;
185  nb_frames++;
186  } else
187  nb_invalid++;
188  break;
189  default:
190  if ( (c >= 0x02 && c <= 0xBF)
191  || c == 0xC8) {
192  nb_invalid++;
193  }
194  }
195  }
196 
197  if (nb_invalid*4 + 1 < nb_frames) {
198  static const char ct_jpeg[] = "\r\nContent-Type: image/jpeg\r\n";
199  int i;
200 
201  for (i=0; i<FFMIN(p->buf_size - (int)sizeof(ct_jpeg), 100); i++)
202  if (!memcmp(p->buf + i, ct_jpeg, sizeof(ct_jpeg) - 1))
204 
205  if (nb_invalid == 0 && nb_frames > 2)
206  return AVPROBE_SCORE_EXTENSION / 2;
207  return AVPROBE_SCORE_EXTENSION / 4;
208  }
209 
210  return 0;
211 }
212 
213 FF_DEF_RAWVIDEO_DEMUXER2(mjpeg, "raw MJPEG video", mjpeg_probe, "mjpg,mjpeg,mpo", AV_CODEC_ID_MJPEG, AVFMT_GENERIC_INDEX|AVFMT_NOTIMESTAMPS)
214 #endif
const AVOption ff_rawvideo_options[]
Definition: rawdec.c:121
#define NULL
Definition: coverity.c:32
AVRational framerate
Definition: avcodec.h:3105
AVOption.
Definition: opt.h:246
int ff_raw_data_read_header(AVFormatContext *s)
Definition: rawdec.c:106
AVInputFormat ff_data_demuxer
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1497
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: avpacket.c:101
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4892
#define FF_DEF_RAWVIDEO_DEMUXER2(shortname, longname, probe, ext, id, flag)
Definition: rawdec.h:71
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3957
int avio_read_partial(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:719
static AVPacket pkt
int framerate
Definition: h264_levels.c:65
static struct @315 state
int ff_raw_subtitle_read_header(AVFormatContext *s)
Definition: rawdec.c:95
Format I/O context.
Definition: avformat.h:1358
Opaque data information usually continuous.
Definition: avutil.h:203
AVOptions.
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
enum AVStreamParseType need_parsing
Definition: avformat.h:1099
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4465
uint8_t * data
Definition: avcodec.h:1477
ptrdiff_t size
Definition: opengl_enc.c:100
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:804
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
const AVOption ff_raw_options[]
Definition: rawdec.c:126
int ff_raw_read_partial_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawdec.c:35
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
ff_const59 struct AVInputFormat * iformat
The input container format.
Definition: avformat.h:1370
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3953
simple assert() macros that are a bit more flexible than ISO C assert().
#define FF_RAW_DEMUXER_CLASS(name)
Definition: rawdec.h:55
#define fail()
Definition: checkasm.h:120
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:449
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
#define FFMIN(a, b)
Definition: common.h:96
int ff_raw_audio_read_header(AVFormatContext *s)
Definition: rawdec.c:56
#define s(width, name)
Definition: cbs_vp9.c:257
#define RAW_PACKET_SIZE
Definition: rawdec.c:33
#define OFFSET(x)
Definition: rawdec.c:119
Stream structure.
Definition: avformat.h:881
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:467
AVStreamInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1238
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
offset must point to AVRational
Definition: opt.h:236
#define s1
Definition: regdef.h:38
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:456
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
misc parsing utilities
int raw_codec_id
Raw demuxers store their codec ID here.
Definition: avformat.h:700
Main libavformat public API header.
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:920
AVRational framerate
AVRational describing framerate, set by a private option.
Definition: rawdec.h:34
void * priv_data
Format private data.
Definition: avformat.h:1386
AVCodecContext * avctx
The codec context used by avformat_find_stream_info, the parser, etc.
Definition: internal.h:172
#define DEC
Definition: rawdec.c:120
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int stream_index
Definition: avcodec.h:1479
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
int ff_raw_video_read_header(AVFormatContext *s)
Definition: rawdec.c:71
This structure stores compressed data.
Definition: avcodec.h:1454