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 <inttypes.h>
23 
24 #include "libavutil/intreadwrite.h"
25 #include "avformat.h"
26 #include "internal.h"
27 #include "riff.h"
28 
29 #define DXA_EXTRA_SIZE 9
30 
31 typedef struct{
32  int frames;
33  int has_sound;
34  int bpc;
35  uint32_t bytes_left;
36  int64_t wavpos, vidpos;
37  int readvid;
38 }DXAContext;
39 
40 static int dxa_probe(AVProbeData *p)
41 {
42  int w, h;
43  if (p->buf_size < 15)
44  return 0;
45  w = AV_RB16(p->buf + 11);
46  h = AV_RB16(p->buf + 13);
47  /* check file header */
48  if (p->buf[0] == 'D' && p->buf[1] == 'E' &&
49  p->buf[2] == 'X' && p->buf[3] == 'A' &&
50  w && w <= 2048 && h && h <= 2048)
51  return AVPROBE_SCORE_MAX;
52  else
53  return 0;
54 }
55 
57 {
58  AVIOContext *pb = s->pb;
59  DXAContext *c = s->priv_data;
60  AVStream *st, *ast;
61  uint32_t tag;
62  int32_t fps;
63  int w, h;
64  int num, den;
65  int flags;
66  int ret;
67 
68  tag = avio_rl32(pb);
69  if (tag != MKTAG('D', 'E', 'X', 'A'))
70  return -1;
71  flags = avio_r8(pb);
72  c->frames = avio_rb16(pb);
73  if(!c->frames){
74  av_log(s, AV_LOG_ERROR, "File contains no frames ???\n");
75  return -1;
76  }
77 
78  fps = avio_rb32(pb);
79  if(fps > 0){
80  den = 1000;
81  num = fps;
82  }else if (fps < 0){
83  den = 100000;
84  num = -fps;
85  }else{
86  den = 10;
87  num = 1;
88  }
89  w = avio_rb16(pb);
90  h = avio_rb16(pb);
91  c->has_sound = 0;
92 
93  st = avformat_new_stream(s, NULL);
94  if (!st)
95  return -1;
96 
97  // Parse WAV data header
98  if(avio_rl32(pb) == MKTAG('W', 'A', 'V', 'E')){
99  uint32_t size, fsize;
100  c->has_sound = 1;
101  size = avio_rb32(pb);
102  c->vidpos = avio_tell(pb) + size;
103  avio_skip(pb, 16);
104  fsize = avio_rl32(pb);
105 
106  ast = avformat_new_stream(s, NULL);
107  if (!ast)
108  return -1;
109  ret = ff_get_wav_header(pb, ast->codec, fsize);
110  if (ret < 0)
111  return ret;
112  if (ast->codec->sample_rate > 0)
113  avpriv_set_pts_info(ast, 64, 1, ast->codec->sample_rate);
114  // find 'data' chunk
115  while(avio_tell(pb) < c->vidpos && !pb->eof_reached){
116  tag = avio_rl32(pb);
117  fsize = avio_rl32(pb);
118  if(tag == MKTAG('d', 'a', 't', 'a')) break;
119  avio_skip(pb, fsize);
120  }
121  c->bpc = (fsize + c->frames - 1) / c->frames;
122  if(ast->codec->block_align)
123  c->bpc = ((c->bpc + ast->codec->block_align - 1) / ast->codec->block_align) * ast->codec->block_align;
124  c->bytes_left = fsize;
125  c->wavpos = avio_tell(pb);
126  avio_seek(pb, c->vidpos, SEEK_SET);
127  }
128 
129  /* now we are ready: build format streams */
132  st->codec->width = w;
133  st->codec->height = h;
134  av_reduce(&den, &num, den, num, (1UL<<31)-1);
135  avpriv_set_pts_info(st, 33, num, den);
136  /* flags & 0x80 means that image is interlaced,
137  * flags & 0x40 means that image has double height
138  * either way set true height
139  */
140  if(flags & 0xC0){
141  st->codec->height >>= 1;
142  }
143  c->readvid = !c->has_sound;
144  c->vidpos = avio_tell(pb);
145  s->start_time = 0;
146  s->duration = (int64_t)c->frames * AV_TIME_BASE * num / den;
147  av_log(s, AV_LOG_DEBUG, "%d frame(s)\n",c->frames);
148 
149  return 0;
150 }
151 
153 {
154  DXAContext *c = s->priv_data;
155  int ret;
156  uint32_t size;
157  uint8_t buf[DXA_EXTRA_SIZE], pal[768+4];
158  int pal_size = 0;
159 
160  if(!c->readvid && c->has_sound && c->bytes_left){
161  c->readvid = 1;
162  avio_seek(s->pb, c->wavpos, SEEK_SET);
163  size = FFMIN(c->bytes_left, c->bpc);
164  ret = av_get_packet(s->pb, pkt, size);
165  pkt->stream_index = 1;
166  if(ret != size)
167  return AVERROR(EIO);
168  c->bytes_left -= size;
169  c->wavpos = avio_tell(s->pb);
170  return 0;
171  }
172  avio_seek(s->pb, c->vidpos, SEEK_SET);
173  while(!s->pb->eof_reached && c->frames){
174  avio_read(s->pb, buf, 4);
175  switch(AV_RL32(buf)){
176  case MKTAG('N', 'U', 'L', 'L'):
177  if(av_new_packet(pkt, 4 + pal_size) < 0)
178  return AVERROR(ENOMEM);
179  pkt->stream_index = 0;
180  if(pal_size) memcpy(pkt->data, pal, pal_size);
181  memcpy(pkt->data + pal_size, buf, 4);
182  c->frames--;
183  c->vidpos = avio_tell(s->pb);
184  c->readvid = 0;
185  return 0;
186  case MKTAG('C', 'M', 'A', 'P'):
187  pal_size = 768+4;
188  memcpy(pal, buf, 4);
189  avio_read(s->pb, pal + 4, 768);
190  break;
191  case MKTAG('F', 'R', 'A', 'M'):
192  avio_read(s->pb, buf + 4, DXA_EXTRA_SIZE - 4);
193  size = AV_RB32(buf + 5);
194  if(size > 0xFFFFFF){
195  av_log(s, AV_LOG_ERROR, "Frame size is too big: %"PRIu32"\n",
196  size);
197  return -1;
198  }
199  if(av_new_packet(pkt, size + DXA_EXTRA_SIZE + pal_size) < 0)
200  return AVERROR(ENOMEM);
201  memcpy(pkt->data + pal_size, buf, DXA_EXTRA_SIZE);
202  ret = avio_read(s->pb, pkt->data + DXA_EXTRA_SIZE + pal_size, size);
203  if(ret != size){
204  av_free_packet(pkt);
205  return AVERROR(EIO);
206  }
207  if(pal_size) memcpy(pkt->data, pal, pal_size);
208  pkt->stream_index = 0;
209  c->frames--;
210  c->vidpos = avio_tell(s->pb);
211  c->readvid = 0;
212  return 0;
213  default:
214  av_log(s, AV_LOG_ERROR, "Unknown tag %c%c%c%c\n", buf[0], buf[1], buf[2], buf[3]);
215  return -1;
216  }
217  }
218  return AVERROR(EIO);
219 }
220 
222  .name = "dxa",
223  .long_name = NULL_IF_CONFIG_SMALL("DXA"),
224  .priv_data_size = sizeof(DXAContext),
228 };
static int dxa_probe(AVProbeData *p)
Definition: dxa.c:40
Bytestream IO Context.
Definition: avio.h:68
int size
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:243
AVInputFormat ff_dxa_demuxer
Definition: dxa.c:221
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:2800
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:186
int readvid
Definition: dxa.c:37
static int dxa_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dxa.c:152
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:580
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:1822
Format I/O context.
Definition: avformat.h:922
uint8_t
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:595
#define AV_RB32
Definition: intreadwrite.h:130
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:2497
uint8_t * data
Definition: avcodec.h:967
static int flags
Definition: log.c:44
uint32_t tag
Definition: movenc.c:844
int64_t vidpos
Definition: dxa.c:36
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:117
int has_sound
Definition: dxa.c:33
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:452
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:81
#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:564
#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:150
#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:168
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:443
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:718
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:398
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:397
static int dxa_read_header(AVFormatContext *s)
Definition: dxa.c:56
int frames
Definition: dxa.c:32
#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:1218
Definition: dxa.c:31
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:544
Stream structure.
Definition: avformat.h:699
NULL
Definition: eval.c:55
enum AVMediaType codec_type
Definition: avcodec.h:1052
enum AVCodecID codec_id
Definition: avcodec.h:1061
int sample_rate
samples per second
Definition: avcodec.h:1785
AVIOContext * pb
I/O context.
Definition: avformat.h:964
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:395
int64_t start_time
Position of the first frame of the component, in AV_TIME_BASE fractional seconds. ...
Definition: avformat.h:1007
#define DXA_EXTRA_SIZE
Definition: dxa.c:29
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:404
Main libavformat public API header.
uint32_t bytes_left
Definition: dxa.c:35
int eof_reached
true if eof reached
Definition: avio.h:96
void * priv_data
Format private data.
Definition: avformat.h:950
int64_t duration
Duration of the stream, in AV_TIME_BASE fractional seconds.
Definition: avformat.h:1017
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:525
int stream_index
Definition: avcodec.h:969
#define MKTAG(a, b, c, d)
Definition: common.h:238
This structure stores compressed data.
Definition: avcodec.h:944
int bpc
Definition: dxa.c:34
int64_t wavpos
Definition: dxa.c:36