FFmpeg  4.2.2
rawdec.c
Go to the documentation of this file.
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
int size
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:4886
#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:716
static AVPacket pkt
int framerate
Definition: h264_levels.c:65
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.
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:4459
uint8_t * data
Definition: avcodec.h:1477
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
#define AVERROR(e)
Definition: error.h:43
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
static struct @313 state
#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
static double c[64]
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
int ff_raw_video_read_header(AVFormatContext *s)
Definition: rawdec.c:71
This structure stores compressed data.
Definition: avcodec.h:1454