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
223
224
|
/*
* Flash Compatible Streaming Format demuxer
* Copyright (c) 2000 Fabrice Bellard
* Copyright (c) 2003 Tinic Uro
*
* 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 "swf.h"
static int get_swf_tag(AVIOContext *pb, int *len_ptr)
{
int tag, len;
if (pb->eof_reached)
return -1;
tag = avio_rl16(pb);
len = tag & 0x3f;
tag = tag >> 6;
if (len == 0x3f) {
len = avio_rl32(pb);
}
// av_log(NULL, AV_LOG_DEBUG, "Tag: %d - Len: %d\n", tag, len);
*len_ptr = len;
return tag;
}
static int swf_probe(AVProbeData *p)
{
/* check file header */
if ((p->buf[0] == 'F' || p->buf[0] == 'C') && p->buf[1] == 'W' &&
p->buf[2] == 'S')
return AVPROBE_SCORE_MAX;
else
return 0;
}
static int swf_read_header(AVFormatContext *s, AVFormatParameters *ap)
{
SWFContext *swf = s->priv_data;
AVIOContext *pb = s->pb;
int nbits, len, tag;
tag = avio_rb32(pb) & 0xffffff00;
if (tag == MKBETAG('C', 'W', 'S', 0)) {
av_log(s, AV_LOG_ERROR, "Compressed SWF format not supported\n");
return AVERROR(EIO);
}
if (tag != MKBETAG('F', 'W', 'S', 0))
return AVERROR(EIO);
avio_rl32(pb);
/* skip rectangle size */
nbits = avio_r8(pb) >> 3;
len = (4 * nbits - 3 + 7) / 8;
avio_skip(pb, len);
swf->frame_rate = avio_rl16(pb); /* 8.8 fixed */
avio_rl16(pb); /* frame count */
swf->samples_per_frame = 0;
s->ctx_flags |= AVFMTCTX_NOHEADER;
return 0;
}
static int swf_read_packet(AVFormatContext *s, AVPacket *pkt)
{
SWFContext *swf = s->priv_data;
AVIOContext *pb = s->pb;
AVStream *vst = NULL, *ast = NULL, *st = 0;
int tag, len, i, frame, v, res;
for(;;) {
uint64_t pos = avio_tell(pb);
tag = get_swf_tag(pb, &len);
if (tag < 0)
return AVERROR(EIO);
if (tag == TAG_VIDEOSTREAM) {
int ch_id = avio_rl16(pb);
len -= 2;
for (i=0; i<s->nb_streams; i++) {
st = s->streams[i];
if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO && st->id == ch_id)
goto skip;
}
avio_rl16(pb);
avio_rl16(pb);
avio_rl16(pb);
avio_r8(pb);
/* Check for FLV1 */
vst = avformat_new_stream(s, NULL);
if (!vst)
return -1;
vst->id = ch_id;
vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
vst->codec->codec_id = ff_codec_get_id(swf_codec_tags, avio_r8(pb));
avpriv_set_pts_info(vst, 16, 256, swf->frame_rate);
vst->codec->time_base = (AVRational){ 256, swf->frame_rate };
len -= 8;
} else if (tag == TAG_STREAMHEAD || tag == TAG_STREAMHEAD2) {
/* streaming found */
int sample_rate_code;
for (i=0; i<s->nb_streams; i++) {
st = s->streams[i];
if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO && st->id == -1)
goto skip;
}
avio_r8(pb);
v = avio_r8(pb);
swf->samples_per_frame = avio_rl16(pb);
ast = avformat_new_stream(s, NULL);
if (!ast)
return -1;
ast->id = -1; /* -1 to avoid clash with video stream ch_id */
ast->codec->channels = 1 + (v&1);
ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
ast->codec->codec_id = ff_codec_get_id(swf_audio_codec_tags, (v>>4) & 15);
ast->need_parsing = AVSTREAM_PARSE_FULL;
sample_rate_code= (v>>2) & 3;
if (!sample_rate_code)
ast->codec->sample_rate = 5512;
else
ast->codec->sample_rate = 11025 << (sample_rate_code-1);
avpriv_set_pts_info(ast, 64, 1, ast->codec->sample_rate);
len -= 4;
} else if (tag == TAG_VIDEOFRAME) {
int ch_id = avio_rl16(pb);
len -= 2;
for(i=0; i<s->nb_streams; i++) {
st = s->streams[i];
if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO && st->id == ch_id) {
frame = avio_rl16(pb);
if ((res = av_get_packet(pb, pkt, len-2)) < 0)
return res;
pkt->pos = pos;
pkt->pts = frame;
pkt->stream_index = st->index;
return pkt->size;
}
}
} else if (tag == TAG_STREAMBLOCK) {
for (i = 0; i < s->nb_streams; i++) {
st = s->streams[i];
if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO && st->id == -1) {
if (st->codec->codec_id == CODEC_ID_MP3) {
avio_skip(pb, 4);
if ((res = av_get_packet(pb, pkt, len-4)) < 0)
return res;
} else { // ADPCM, PCM
if ((res = av_get_packet(pb, pkt, len)) < 0)
return res;
}
pkt->pos = pos;
pkt->stream_index = st->index;
return pkt->size;
}
}
} else if (tag == TAG_JPEG2) {
for (i=0; i<s->nb_streams; i++) {
st = s->streams[i];
if (st->codec->codec_id == CODEC_ID_MJPEG && st->id == -2)
break;
}
if (i == s->nb_streams) {
vst = avformat_new_stream(s, NULL);
if (!vst)
return -1;
vst->id = -2; /* -2 to avoid clash with video stream and audio stream */
vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
vst->codec->codec_id = CODEC_ID_MJPEG;
avpriv_set_pts_info(vst, 64, 256, swf->frame_rate);
vst->codec->time_base = (AVRational){ 256, swf->frame_rate };
st = vst;
}
avio_rl16(pb); /* BITMAP_ID */
if ((res = av_new_packet(pkt, len-2)) < 0)
return res;
avio_read(pb, pkt->data, 4);
if (AV_RB32(pkt->data) == 0xffd8ffd9 ||
AV_RB32(pkt->data) == 0xffd9ffd8) {
/* old SWF files containing SOI/EOI as data start */
/* files created by swink have reversed tag */
pkt->size -= 4;
avio_read(pb, pkt->data, pkt->size);
} else {
avio_read(pb, pkt->data + 4, pkt->size - 4);
}
pkt->pos = pos;
pkt->stream_index = st->index;
return pkt->size;
}
skip:
avio_skip(pb, len);
}
}
AVInputFormat ff_swf_demuxer = {
.name = "swf",
.long_name = NULL_IF_CONFIG_SMALL("Flash format"),
.priv_data_size = sizeof(SWFContext),
.read_probe = swf_probe,
.read_header = swf_read_header,
.read_packet = swf_read_packet,
};
|
