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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 {
37  int ret, size;
38 
39  size = RAW_PACKET_SIZE;
40 
41  if (av_new_packet(pkt, size) < 0)
42  return AVERROR(ENOMEM);
43 
44  pkt->pos= avio_tell(s->pb);
45  pkt->stream_index = 0;
46  ret = ffio_read_partial(s->pb, pkt->data, size);
47  if (ret < 0) {
48  av_packet_unref(pkt);
49  return ret;
50  }
51  av_shrink_packet(pkt, ret);
52  return ret;
53 }
54 
56 {
58  if (!st)
59  return AVERROR(ENOMEM);
63  st->start_time = 0;
64  /* the parameters will be extracted from the compressed bitstream */
65 
66  return 0;
67 }
68 
69 /* MPEG-1/H.263 input */
71 {
72  AVStream *st;
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 
86 
87  st->internal->avctx->framerate = s1->framerate;
88  avpriv_set_pts_info(st, 64, 1, 1200000);
89 
90 fail:
91  return ret;
92 }
93 
95 {
97  if (!st)
98  return AVERROR(ENOMEM);
101  st->start_time = 0;
102  return 0;
103 }
104 
105 /* Note: Do not forget to add new entries to the Makefile as well. */
106 
107 #define OFFSET(x) offsetof(FFRawVideoDemuxerContext, x)
108 #define DEC AV_OPT_FLAG_DECODING_PARAM
110  { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, DEC},
111  { NULL },
112 };
113 
114 #if CONFIG_DATA_DEMUXER
115 AVInputFormat ff_data_demuxer = {
116  .name = "data",
117  .long_name = NULL_IF_CONFIG_SMALL("raw data"),
118  .read_header = ff_raw_data_read_header,
119  .read_packet = ff_raw_read_partial_packet,
120  .raw_codec_id = AV_CODEC_ID_NONE,
121  .flags = AVFMT_NOTIMESTAMPS,
122 };
123 #endif
124 
125 #if CONFIG_MJPEG_DEMUXER
126 static int mjpeg_probe(AVProbeData *p)
127 {
128  int i;
129  int state = -1;
130  int nb_invalid = 0;
131  int nb_frames = 0;
132 
133  for (i=0; i<p->buf_size-2; i++) {
134  int c;
135  if (p->buf[i] != 0xFF)
136  continue;
137  c = p->buf[i+1];
138  switch (c) {
139  case 0xD8:
140  state = 0xD8;
141  break;
142  case 0xC0:
143  case 0xC1:
144  case 0xC2:
145  case 0xC3:
146  case 0xC5:
147  case 0xC6:
148  case 0xC7:
149  case 0xF7:
150  if (state == 0xD8) {
151  state = 0xC0;
152  } else
153  nb_invalid++;
154  break;
155  case 0xDA:
156  if (state == 0xC0) {
157  state = 0xDA;
158  } else
159  nb_invalid++;
160  break;
161  case 0xD9:
162  if (state == 0xDA) {
163  state = 0xD9;
164  nb_frames++;
165  } else
166  nb_invalid++;
167  break;
168  default:
169  if ( (c >= 0x02 && c <= 0xBF)
170  || c == 0xC8) {
171  nb_invalid++;
172  }
173  }
174  }
175 
176  if (nb_invalid*4 + 1 < nb_frames) {
177  static const char ct_jpeg[] = "\r\nContent-Type: image/jpeg\r\n";
178  int i;
179 
180  for (i=0; i<FFMIN(p->buf_size - (int)sizeof(ct_jpeg), 100); i++)
181  if (!memcmp(p->buf + i, ct_jpeg, sizeof(ct_jpeg) - 1))
183 
184  if (nb_invalid == 0 && nb_frames > 2)
185  return AVPROBE_SCORE_EXTENSION / 2;
186  return AVPROBE_SCORE_EXTENSION / 4;
187  }
188 
189  return 0;
190 }
191 
192 FF_DEF_RAWVIDEO_DEMUXER2(mjpeg, "raw MJPEG video", mjpeg_probe, "mjpg,mjpeg,mpo", AV_CODEC_ID_MJPEG, AVFMT_GENERIC_INDEX|AVFMT_NOTIMESTAMPS)
193 #endif
const AVOption ff_rawvideo_options[]
Definition: rawdec.c:109
#define NULL
Definition: coverity.c:32
AVRational framerate
Definition: avcodec.h:3374
const char * s
Definition: avisynth_c.h:768
AVOption.
Definition: opt.h:245
int ff_raw_data_read_header(AVFormatContext *s)
Definition: rawdec.c:94
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1620
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:4549
#define FF_DEF_RAWVIDEO_DEMUXER2(shortname, longname, probe, ext, id, flag)
Definition: rawdec.h:54
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3979
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1330
Opaque data information usually continuous.
Definition: avutil.h:197
AVOptions.
enum AVStreamParseType need_parsing
Definition: avformat.h:1068
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4182
uint8_t * data
Definition: avcodec.h:1600
ptrdiff_t size
Definition: opengl_enc.c:101
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:511
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:812
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 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:176
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3975
simple assert() macros that are a bit more flexible than ISO C assert().
int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:673
#define fail()
Definition: checkasm.h:82
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:464
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:463
#define FFMIN(a, b)
Definition: common.h:96
int ff_raw_audio_read_header(AVFormatContext *s)
Definition: rawdec.c:55
#define RAW_PACKET_SIZE
Definition: rawdec.c:33
#define OFFSET(x)
Definition: rawdec.c:107
Stream structure.
Definition: avformat.h:881
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:486
AVStreamInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1222
AVIOContext * pb
I/O context.
Definition: avformat.h:1372
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:567
static struct @246 state
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:487
offset must point to AVRational
Definition: opt.h:235
#define s1
Definition: regdef.h:38
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:471
This structure contains the data a format has to probe a file.
Definition: avformat.h:461
misc parsing utilities
int raw_codec_id
Raw demuxers store their codec ID here.
Definition: avformat.h:708
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:928
static double c[64]
struct AVInputFormat * iformat
The input container format.
Definition: avformat.h:1342
AVRational framerate
AVRational describing framerate, set by a private option.
Definition: rawdec.h:33
void * priv_data
Format private data.
Definition: avformat.h:1358
AVCodecContext * avctx
The codec context used by avformat_find_stream_info, the parser, etc.
Definition: internal.h:158
#define DEC
Definition: rawdec.c:108
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:662
AVCodecParameters * codecpar
Definition: avformat.h:1233
int stream_index
Definition: avcodec.h:1602
int ff_raw_video_read_header(AVFormatContext *s)
Definition: rawdec.c:70
This structure stores compressed data.
Definition: avcodec.h:1577