1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
|
/*
* DXA demuxer
* Copyright (c) 2007 Konstantin Shishkov
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "riff.h"
#define DXA_EXTRA_SIZE 9
typedef struct{
int frames;
int has_sound;
int bpc;
uint32_t bytes_left;
int64_t wavpos, vidpos;
int readvid;
}DXAContext;
static int dxa_probe(AVProbeData *p)
{
int w, h;
if (p->buf_size < 15)
return 0;
w = AV_RB16(p->buf + 11);
h = AV_RB16(p->buf + 13);
/* check file header */
if (p->buf[0] == 'D' && p->buf[1] == 'E' &&
p->buf[2] == 'X' && p->buf[3] == 'A' &&
w && w <= 2048 && h && h <= 2048)
return AVPROBE_SCORE_MAX;
else
return 0;
}
static int dxa_read_header(AVFormatContext *s, AVFormatParameters *ap)
{
AVIOContext *pb = s->pb;
DXAContext *c = s->priv_data;
AVStream *st, *ast;
uint32_t tag;
int32_t fps;
int w, h;
int num, den;
int flags;
int ret;
tag = avio_rl32(pb);
if (tag != MKTAG('D', 'E', 'X', 'A'))
return -1;
flags = avio_r8(pb);
c->frames = avio_rb16(pb);
if(!c->frames){
av_log(s, AV_LOG_ERROR, "File contains no frames ???\n");
return -1;
}
fps = avio_rb32(pb);
if(fps > 0){
den = 1000;
num = fps;
}else if (fps < 0){
den = 100000;
num = -fps;
}else{
den = 10;
num = 1;
}
w = avio_rb16(pb);
h = avio_rb16(pb);
c->has_sound = 0;
st = av_new_stream(s, 0);
if (!st)
return -1;
// Parse WAV data header
if(avio_rl32(pb) == MKTAG('W', 'A', 'V', 'E')){
uint32_t size, fsize;
c->has_sound = 1;
size = avio_rb32(pb);
c->vidpos = avio_tell(pb) + size;
avio_skip(pb, 16);
fsize = avio_rl32(pb);
ast = av_new_stream(s, 0);
if (!ast)
return -1;
ret = ff_get_wav_header(pb, ast->codec, fsize);
if (ret < 0)
return ret;
// find 'data' chunk
while(avio_tell(pb) < c->vidpos && !pb->eof_reached){
tag = avio_rl32(pb);
fsize = avio_rl32(pb);
if(tag == MKTAG('d', 'a', 't', 'a')) break;
avio_skip(pb, fsize);
}
c->bpc = (fsize + c->frames - 1) / c->frames;
if(ast->codec->block_align)
c->bpc = ((c->bpc + ast->codec->block_align - 1) / ast->codec->block_align) * ast->codec->block_align;
c->bytes_left = fsize;
c->wavpos = avio_tell(pb);
avio_seek(pb, c->vidpos, SEEK_SET);
}
/* now we are ready: build format streams */
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_id = CODEC_ID_DXA;
st->codec->width = w;
st->codec->height = h;
av_reduce(&den, &num, den, num, (1UL<<31)-1);
av_set_pts_info(st, 33, num, den);
/* flags & 0x80 means that image is interlaced,
* flags & 0x40 means that image has double height
* either way set true height
*/
if(flags & 0xC0){
st->codec->height >>= 1;
}
c->readvid = !c->has_sound;
c->vidpos = avio_tell(pb);
s->start_time = 0;
s->duration = (int64_t)c->frames * AV_TIME_BASE * num / den;
av_log(s, AV_LOG_DEBUG, "%d frame(s)\n",c->frames);
return 0;
}
static int dxa_read_packet(AVFormatContext *s, AVPacket *pkt)
{
DXAContext *c = s->priv_data;
int ret;
uint32_t size;
uint8_t buf[DXA_EXTRA_SIZE], pal[768+4];
int pal_size = 0;
if(!c->readvid && c->has_sound && c->bytes_left){
c->readvid = 1;
avio_seek(s->pb, c->wavpos, SEEK_SET);
size = FFMIN(c->bytes_left, c->bpc);
ret = av_get_packet(s->pb, pkt, size);
pkt->stream_index = 1;
if(ret != size)
return AVERROR(EIO);
c->bytes_left -= size;
c->wavpos = avio_tell(s->pb);
return 0;
}
avio_seek(s->pb, c->vidpos, SEEK_SET);
while(!s->pb->eof_reached && c->frames){
avio_read(s->pb, buf, 4);
switch(AV_RL32(buf)){
case MKTAG('N', 'U', 'L', 'L'):
if(av_new_packet(pkt, 4 + pal_size) < 0)
return AVERROR(ENOMEM);
pkt->stream_index = 0;
if(pal_size) memcpy(pkt->data, pal, pal_size);
memcpy(pkt->data + pal_size, buf, 4);
c->frames--;
c->vidpos = avio_tell(s->pb);
c->readvid = 0;
return 0;
case MKTAG('C', 'M', 'A', 'P'):
pal_size = 768+4;
memcpy(pal, buf, 4);
avio_read(s->pb, pal + 4, 768);
break;
case MKTAG('F', 'R', 'A', 'M'):
avio_read(s->pb, buf + 4, DXA_EXTRA_SIZE - 4);
size = AV_RB32(buf + 5);
if(size > 0xFFFFFF){
av_log(s, AV_LOG_ERROR, "Frame size is too big: %d\n", size);
return -1;
}
if(av_new_packet(pkt, size + DXA_EXTRA_SIZE + pal_size) < 0)
return AVERROR(ENOMEM);
memcpy(pkt->data + pal_size, buf, DXA_EXTRA_SIZE);
ret = avio_read(s->pb, pkt->data + DXA_EXTRA_SIZE + pal_size, size);
if(ret != size){
av_free_packet(pkt);
return AVERROR(EIO);
}
if(pal_size) memcpy(pkt->data, pal, pal_size);
pkt->stream_index = 0;
c->frames--;
c->vidpos = avio_tell(s->pb);
c->readvid = 0;
return 0;
default:
av_log(s, AV_LOG_ERROR, "Unknown tag %c%c%c%c\n", buf[0], buf[1], buf[2], buf[3]);
return -1;
}
}
return AVERROR(EIO);
}
AVInputFormat ff_dxa_demuxer = {
"dxa",
NULL_IF_CONFIG_SMALL("DXA"),
sizeof(DXAContext),
dxa_probe,
dxa_read_header,
dxa_read_packet,
};
|
