FFmpeg
dxa.c
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1 /*
2  * DXA demuxer
3  * Copyright (c) 2007 Konstantin Shishkov
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include <inttypes.h>
23 
24 #include "libavutil/intreadwrite.h"
25 #include "avformat.h"
26 #include "demux.h"
27 #include "internal.h"
28 #include "riff.h"
29 
30 #define DXA_EXTRA_SIZE 9
31 
32 typedef struct DXAContext {
33  int frames;
34  int has_sound;
35  int bpc;
36  uint32_t bytes_left;
37  int64_t wavpos, vidpos;
38  int readvid;
39 }DXAContext;
40 
41 static int dxa_probe(const AVProbeData *p)
42 {
43  int w, h;
44  if (p->buf_size < 15)
45  return 0;
46  w = AV_RB16(p->buf + 11);
47  h = AV_RB16(p->buf + 13);
48  /* check file header */
49  if (p->buf[0] == 'D' && p->buf[1] == 'E' &&
50  p->buf[2] == 'X' && p->buf[3] == 'A' &&
51  w && w <= 2048 && h && h <= 2048)
52  return AVPROBE_SCORE_MAX;
53  else
54  return 0;
55 }
56 
57 static int dxa_read_header(AVFormatContext *s)
58 {
59  AVIOContext *pb = s->pb;
60  DXAContext *c = s->priv_data;
61  AVStream *st, *ast;
62  uint32_t tag;
63  int32_t fps;
64  int w, h;
65  int num, den;
66  int flags;
67  int ret;
68 
69  tag = avio_rl32(pb);
70  if (tag != MKTAG('D', 'E', 'X', 'A'))
71  return AVERROR_INVALIDDATA;
72  flags = avio_r8(pb);
73  c->frames = avio_rb16(pb);
74  if(!c->frames){
75  av_log(s, AV_LOG_ERROR, "File contains no frames ???\n");
76  return AVERROR_INVALIDDATA;
77  }
78 
79  fps = avio_rb32(pb);
80  if(fps > 0){
81  den = 1000;
82  num = fps;
83  }else if (fps < 0 && fps > INT_MIN){
84  den = 100000;
85  num = -fps;
86  }else{
87  den = 10;
88  num = 1;
89  }
90  w = avio_rb16(pb);
91  h = avio_rb16(pb);
92  c->has_sound = 0;
93 
94  st = avformat_new_stream(s, NULL);
95  if (!st)
96  return AVERROR(ENOMEM);
97 
98  // Parse WAV data header
99  if(avio_rl32(pb) == MKTAG('W', 'A', 'V', 'E')){
100  uint32_t size, fsize;
101  c->has_sound = 1;
102  size = avio_rb32(pb);
103  c->vidpos = avio_tell(pb) + size;
104  avio_skip(pb, 16);
105  fsize = avio_rl32(pb);
106 
107  ast = avformat_new_stream(s, NULL);
108  if (!ast)
109  return AVERROR(ENOMEM);
110  ret = ff_get_wav_header(s, pb, ast->codecpar, fsize, 0);
111  if (ret < 0)
112  return ret;
113  if (ast->codecpar->sample_rate > 0)
114  avpriv_set_pts_info(ast, 64, 1, ast->codecpar->sample_rate);
115  // find 'data' chunk
116  while(avio_tell(pb) < c->vidpos && !avio_feof(pb)){
117  tag = avio_rl32(pb);
118  fsize = avio_rl32(pb);
119  if(tag == MKTAG('d', 'a', 't', 'a')) break;
120  avio_skip(pb, fsize);
121  }
122  c->bpc = (fsize + (int64_t)c->frames - 1) / c->frames;
123  if(ast->codecpar->block_align) {
124  if (c->bpc > INT_MAX - ast->codecpar->block_align + 1)
125  return AVERROR_INVALIDDATA;
126  c->bpc = ((c->bpc - 1 + ast->codecpar->block_align) / ast->codecpar->block_align) * ast->codecpar->block_align;
127  }
128  c->bytes_left = fsize;
129  c->wavpos = avio_tell(pb);
130  avio_seek(pb, c->vidpos, SEEK_SET);
131  }
132 
133  /* now we are ready: build format streams */
134  st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
135  st->codecpar->codec_id = AV_CODEC_ID_DXA;
136  st->codecpar->width = w;
137  st->codecpar->height = h;
138  av_reduce(&den, &num, den, num, (1UL<<31)-1);
139  avpriv_set_pts_info(st, 33, num, den);
140  /* flags & 0x80 means that image is interlaced,
141  * flags & 0x40 means that image has double height
142  * either way set true height
143  */
144  if(flags & 0xC0){
145  st->codecpar->height >>= 1;
146  }
147  c->readvid = !c->has_sound;
148  c->vidpos = avio_tell(pb);
149  s->start_time = 0;
150  s->duration = av_rescale(c->frames, AV_TIME_BASE * (int64_t)num, den);
151  av_log(s, AV_LOG_DEBUG, "%d frame(s)\n",c->frames);
152 
153  return 0;
154 }
155 
156 static int dxa_read_packet(AVFormatContext *s, AVPacket *pkt)
157 {
158  DXAContext *c = s->priv_data;
159  int ret;
160  uint32_t size;
161  uint8_t buf[DXA_EXTRA_SIZE], pal[768+4];
162  int pal_size = 0;
163 
164  if(!c->readvid && c->has_sound && c->bytes_left){
165  c->readvid = 1;
166  avio_seek(s->pb, c->wavpos, SEEK_SET);
167  size = FFMIN(c->bytes_left, c->bpc);
168  ret = av_get_packet(s->pb, pkt, size);
169  pkt->stream_index = 1;
170  if(ret != size)
171  return AVERROR(EIO);
172  c->bytes_left -= size;
173  c->wavpos = avio_tell(s->pb);
174  return 0;
175  }
176  avio_seek(s->pb, c->vidpos, SEEK_SET);
177  while(!avio_feof(s->pb) && c->frames){
178  uint32_t tag;
179  if ((ret = avio_read(s->pb, buf, 4)) != 4) {
180  av_log(s, AV_LOG_ERROR, "failed reading chunk type\n");
181  return ret < 0 ? ret : AVERROR_INVALIDDATA;
182  }
183  tag = AV_RL32(buf);
184  switch (tag) {
185  case MKTAG('N', 'U', 'L', 'L'):
186  if ((ret = av_new_packet(pkt, 4 + pal_size)) < 0)
187  return ret;
188  pkt->stream_index = 0;
189  if(pal_size) memcpy(pkt->data, pal, pal_size);
190  memcpy(pkt->data + pal_size, buf, 4);
191  c->frames--;
192  c->vidpos = avio_tell(s->pb);
193  c->readvid = 0;
194  return 0;
195  case MKTAG('C', 'M', 'A', 'P'):
196  pal_size = 768+4;
197  memcpy(pal, buf, 4);
198  avio_read(s->pb, pal + 4, 768);
199  break;
200  case MKTAG('F', 'R', 'A', 'M'):
201  if ((ret = avio_read(s->pb, buf + 4, DXA_EXTRA_SIZE - 4)) != DXA_EXTRA_SIZE - 4) {
202  av_log(s, AV_LOG_ERROR, "failed reading dxa_extra\n");
203  return ret < 0 ? ret : AVERROR_INVALIDDATA;
204  }
205  size = AV_RB32(buf + 5);
206  if(size > 0xFFFFFF){
207  av_log(s, AV_LOG_ERROR, "Frame size is too big: %"PRIu32"\n",
208  size);
209  return AVERROR_INVALIDDATA;
210  }
211  ret = av_new_packet(pkt, size + DXA_EXTRA_SIZE + pal_size);
212  if (ret < 0)
213  return ret;
214  memcpy(pkt->data + pal_size, buf, DXA_EXTRA_SIZE);
215  ret = avio_read(s->pb, pkt->data + DXA_EXTRA_SIZE + pal_size, size);
216  if(ret != size){
217  return AVERROR(EIO);
218  }
219  if(pal_size) memcpy(pkt->data, pal, pal_size);
220  pkt->stream_index = 0;
221  c->frames--;
222  c->vidpos = avio_tell(s->pb);
223  c->readvid = 0;
224  return 0;
225  default:
226  av_log(s, AV_LOG_ERROR, "Unknown tag %s\n", av_fourcc2str(tag));
227  return AVERROR_INVALIDDATA;
228  }
229  }
230  return AVERROR_EOF;
231 }
232 
233 const FFInputFormat ff_dxa_demuxer = {
234  .p.name = "dxa",
235  .p.long_name = NULL_IF_CONFIG_SMALL("DXA"),
236  .priv_data_size = sizeof(DXAContext),
237  .read_probe = dxa_probe,
238  .read_header = dxa_read_header,
239  .read_packet = dxa_read_packet,
240 };
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
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
DXAContext::wavpos
int64_t wavpos
Definition: dxa.c:37
DXAContext::bytes_left
uint32_t bytes_left
Definition: dxa.c:36
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
int64_t
long long int64_t
Definition: coverity.c:34
w
uint8_t w
Definition: llviddspenc.c:38
DXAContext::frames
int frames
Definition: dxa.c:33
AVPacket::data
uint8_t * data
Definition: packet.h:539
DXAContext::vidpos
int64_t vidpos
Definition: dxa.c:37
ff_dxa_demuxer
const FFInputFormat ff_dxa_demuxer
Definition: dxa.c:233
dxa_probe
static int dxa_probe(const AVProbeData *p)
Definition: dxa.c:41
ff_get_wav_header
int ff_get_wav_header(void *logctx, AVIOContext *pb, AVCodecParameters *par, int size, int big_endian)
Definition: riffdec.c:95
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:454
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
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:867
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:494
av_reduce
int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max)
Reduce a fraction.
Definition: rational.c:35
DXAContext::has_sound
int has_sound
Definition: dxa.c:34
avio_rb32
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:761
pkt
AVPacket * pkt
Definition: movenc.c:60
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:209
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:42
DXAContext::bpc
int bpc
Definition: dxa.c:35
intreadwrite.h
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
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:134
AV_LOG_DEBUG
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:230
fsize
static int64_t fsize(FILE *f)
Definition: audiomatch.c:29
AVFormatContext
Format I/O context.
Definition: avformat.h:1300
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:771
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:540
NULL
#define NULL
Definition: coverity.c:32
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
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
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
dxa_read_packet
static int dxa_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dxa.c:156
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:730
AVIOContext
Bytestream IO Context.
Definition: avio.h:160
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
size
int size
Definition: twinvq_data.h:10344
AV_RB32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:96
DXA_EXTRA_SIZE
#define DXA_EXTRA_SIZE
Definition: dxa.c:30
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:46
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:603
AV_CODEC_ID_DXA
@ AV_CODEC_ID_DXA
Definition: codec_id.h:150
AVCodecParameters::height
int height
Definition: codec_par.h:135
AV_TIME_BASE
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:254
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:191
DXAContext
Definition: dxa.c:32
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
demux.h
av_rescale
int64_t av_rescale(int64_t a, int64_t b, int64_t c)
Rescale a 64-bit integer with rounding to nearest.
Definition: mathematics.c:129
av_get_packet
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:91
tag
uint32_t tag
Definition: movenc.c:1876
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:748
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:231
avio_rb16
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:746
avformat.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:612
AVPacket::stream_index
int stream_index
Definition: packet.h:541
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:318
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:30
dxa_read_header
static int dxa_read_header(AVFormatContext *s)
Definition: dxa.c:57
DXAContext::readvid
int readvid
Definition: dxa.c:38
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:516
riff.h
FFInputFormat
Definition: demux.h:42
int32_t
int32_t
Definition: audioconvert.c:56
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:482
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
MKTAG
#define MKTAG(a, b, c, d)
Definition: macros.h:55
h
h
Definition: vp9dsp_template.c:2070
AV_RB16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:98
av_fourcc2str
#define av_fourcc2str(fourcc)
Definition: avutil.h:348
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:346
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