Libav
dxa.c
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1 /*
2  * DXA demuxer
3  * Copyright (c) 2007 Konstantin Shishkov
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/intreadwrite.h"
23 #include "avformat.h"
24 #include "internal.h"
25 #include "riff.h"
26 
27 #define DXA_EXTRA_SIZE 9
28 
29 typedef struct{
30  int frames;
31  int has_sound;
32  int bpc;
33  uint32_t bytes_left;
34  int64_t wavpos, vidpos;
35  int readvid;
36 }DXAContext;
37 
38 static int dxa_probe(AVProbeData *p)
39 {
40  int w, h;
41  if (p->buf_size < 15)
42  return 0;
43  w = AV_RB16(p->buf + 11);
44  h = AV_RB16(p->buf + 13);
45  /* check file header */
46  if (p->buf[0] == 'D' && p->buf[1] == 'E' &&
47  p->buf[2] == 'X' && p->buf[3] == 'A' &&
48  w && w <= 2048 && h && h <= 2048)
49  return AVPROBE_SCORE_MAX;
50  else
51  return 0;
52 }
53 
55 {
56  AVIOContext *pb = s->pb;
57  DXAContext *c = s->priv_data;
58  AVStream *st, *ast;
59  uint32_t tag;
60  int32_t fps;
61  int w, h;
62  int num, den;
63  int flags;
64  int ret;
65 
66  tag = avio_rl32(pb);
67  if (tag != MKTAG('D', 'E', 'X', 'A'))
68  return -1;
69  flags = avio_r8(pb);
70  c->frames = avio_rb16(pb);
71  if(!c->frames){
72  av_log(s, AV_LOG_ERROR, "File contains no frames ???\n");
73  return -1;
74  }
75 
76  fps = avio_rb32(pb);
77  if(fps > 0){
78  den = 1000;
79  num = fps;
80  }else if (fps < 0){
81  den = 100000;
82  num = -fps;
83  }else{
84  den = 10;
85  num = 1;
86  }
87  w = avio_rb16(pb);
88  h = avio_rb16(pb);
89  c->has_sound = 0;
90 
91  st = avformat_new_stream(s, NULL);
92  if (!st)
93  return -1;
94 
95  // Parse WAV data header
96  if(avio_rl32(pb) == MKTAG('W', 'A', 'V', 'E')){
97  uint32_t size, fsize;
98  c->has_sound = 1;
99  size = avio_rb32(pb);
100  c->vidpos = avio_tell(pb) + size;
101  avio_skip(pb, 16);
102  fsize = avio_rl32(pb);
103 
104  ast = avformat_new_stream(s, NULL);
105  if (!ast)
106  return -1;
107  ret = ff_get_wav_header(pb, ast->codec, fsize);
108  if (ret < 0)
109  return ret;
110  if (ast->codec->sample_rate > 0)
111  avpriv_set_pts_info(ast, 64, 1, ast->codec->sample_rate);
112  // find 'data' chunk
113  while(avio_tell(pb) < c->vidpos && !pb->eof_reached){
114  tag = avio_rl32(pb);
115  fsize = avio_rl32(pb);
116  if(tag == MKTAG('d', 'a', 't', 'a')) break;
117  avio_skip(pb, fsize);
118  }
119  c->bpc = (fsize + c->frames - 1) / c->frames;
120  if(ast->codec->block_align)
121  c->bpc = ((c->bpc + ast->codec->block_align - 1) / ast->codec->block_align) * ast->codec->block_align;
122  c->bytes_left = fsize;
123  c->wavpos = avio_tell(pb);
124  avio_seek(pb, c->vidpos, SEEK_SET);
125  }
126 
127  /* now we are ready: build format streams */
130  st->codec->width = w;
131  st->codec->height = h;
132  av_reduce(&den, &num, den, num, (1UL<<31)-1);
133  avpriv_set_pts_info(st, 33, num, den);
134  /* flags & 0x80 means that image is interlaced,
135  * flags & 0x40 means that image has double height
136  * either way set true height
137  */
138  if(flags & 0xC0){
139  st->codec->height >>= 1;
140  }
141  c->readvid = !c->has_sound;
142  c->vidpos = avio_tell(pb);
143  s->start_time = 0;
144  s->duration = (int64_t)c->frames * AV_TIME_BASE * num / den;
145  av_log(s, AV_LOG_DEBUG, "%d frame(s)\n",c->frames);
146 
147  return 0;
148 }
149 
151 {
152  DXAContext *c = s->priv_data;
153  int ret;
154  uint32_t size;
155  uint8_t buf[DXA_EXTRA_SIZE], pal[768+4];
156  int pal_size = 0;
157 
158  if(!c->readvid && c->has_sound && c->bytes_left){
159  c->readvid = 1;
160  avio_seek(s->pb, c->wavpos, SEEK_SET);
161  size = FFMIN(c->bytes_left, c->bpc);
162  ret = av_get_packet(s->pb, pkt, size);
163  pkt->stream_index = 1;
164  if(ret != size)
165  return AVERROR(EIO);
166  c->bytes_left -= size;
167  c->wavpos = avio_tell(s->pb);
168  return 0;
169  }
170  avio_seek(s->pb, c->vidpos, SEEK_SET);
171  while(!s->pb->eof_reached && c->frames){
172  avio_read(s->pb, buf, 4);
173  switch(AV_RL32(buf)){
174  case MKTAG('N', 'U', 'L', 'L'):
175  if(av_new_packet(pkt, 4 + pal_size) < 0)
176  return AVERROR(ENOMEM);
177  pkt->stream_index = 0;
178  if(pal_size) memcpy(pkt->data, pal, pal_size);
179  memcpy(pkt->data + pal_size, buf, 4);
180  c->frames--;
181  c->vidpos = avio_tell(s->pb);
182  c->readvid = 0;
183  return 0;
184  case MKTAG('C', 'M', 'A', 'P'):
185  pal_size = 768+4;
186  memcpy(pal, buf, 4);
187  avio_read(s->pb, pal + 4, 768);
188  break;
189  case MKTAG('F', 'R', 'A', 'M'):
190  avio_read(s->pb, buf + 4, DXA_EXTRA_SIZE - 4);
191  size = AV_RB32(buf + 5);
192  if(size > 0xFFFFFF){
193  av_log(s, AV_LOG_ERROR, "Frame size is too big: %d\n", size);
194  return -1;
195  }
196  if(av_new_packet(pkt, size + DXA_EXTRA_SIZE + pal_size) < 0)
197  return AVERROR(ENOMEM);
198  memcpy(pkt->data + pal_size, buf, DXA_EXTRA_SIZE);
199  ret = avio_read(s->pb, pkt->data + DXA_EXTRA_SIZE + pal_size, size);
200  if(ret != size){
201  av_free_packet(pkt);
202  return AVERROR(EIO);
203  }
204  if(pal_size) memcpy(pkt->data, pal, pal_size);
205  pkt->stream_index = 0;
206  c->frames--;
207  c->vidpos = avio_tell(s->pb);
208  c->readvid = 0;
209  return 0;
210  default:
211  av_log(s, AV_LOG_ERROR, "Unknown tag %c%c%c%c\n", buf[0], buf[1], buf[2], buf[3]);
212  return -1;
213  }
214  }
215  return AVERROR(EIO);
216 }
217 
219  .name = "dxa",
220  .long_name = NULL_IF_CONFIG_SMALL("DXA"),
221  .priv_data_size = sizeof(DXAContext),
225 };
static int dxa_probe(AVProbeData *p)
Definition: dxa.c:38
Bytestream IO Context.
Definition: avio.h:68
int size
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:242
AVInputFormat ff_dxa_demuxer
Definition: dxa.c:218
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:3208
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:186
int readvid
Definition: dxa.c:35
static int dxa_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dxa.c:150
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:574
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:1816
Format I/O context.
Definition: avformat.h:871
uint8_t
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:589
#define AV_RB32
Definition: intreadwrite.h:130
uint8_t * data
Definition: avcodec.h:973
static int flags
Definition: log.c:44
uint32_t tag
Definition: movenc.c:822
int64_t vidpos
Definition: dxa.c:34
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:118
int has_sound
Definition: dxa.c:31
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:219
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:446
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:80
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
#define AV_RB16
Definition: intreadwrite.h:53
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:558
#define AVERROR(e)
Definition: error.h:43
int ff_get_wav_header(AVIOContext *pb, AVCodecContext *codec, int size)
Definition: riffdec.c:78
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:142
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:144
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:148
AVStream * avformat_new_stream(AVFormatContext *s, AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:2662
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:437
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:702
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
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:391
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:390
static int dxa_read_header(AVFormatContext *s)
Definition: dxa.c:54
int frames
Definition: dxa.c:30
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:234
#define FFMIN(a, b)
Definition: common.h:57
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
int width
picture width / height.
Definition: avcodec.h:1217
Definition: dxa.c:29
static av_always_inline int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: avio.h:210
internal header for RIFF based (de)muxers do NOT include this in end user applications ...
int32_t
#define AV_RL32
Definition: intreadwrite.h:146
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:536
Stream structure.
Definition: avformat.h:683
NULL
Definition: eval.c:55
enum AVMediaType codec_type
Definition: avcodec.h:1062
enum AVCodecID codec_id
Definition: avcodec.h:1065
int sample_rate
samples per second
Definition: avcodec.h:1779
AVIOContext * pb
I/O context.
Definition: avformat.h:913
static int read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: libcdio.c:114
This structure contains the data a format has to probe a file.
Definition: avformat.h:388
int64_t start_time
Position of the first frame of the component, in AV_TIME_BASE fractional seconds. ...
Definition: avformat.h:952
#define DXA_EXTRA_SIZE
Definition: dxa.c:27
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:395
Main libavformat public API header.
uint32_t bytes_left
Definition: dxa.c:33
int eof_reached
true if eof reached
Definition: avio.h:96
void * priv_data
Format private data.
Definition: avformat.h:899
int64_t duration
Duration of the stream, in AV_TIME_BASE fractional seconds.
Definition: avformat.h:962
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:516
int stream_index
Definition: avcodec.h:975
#define MKTAG(a, b, c, d)
Definition: common.h:238
This structure stores compressed data.
Definition: avcodec.h:950
int bpc
Definition: dxa.c:32
int64_t wavpos
Definition: dxa.c:34