1 /*
2 * Linux Media Labs MPEG-4 demuxer
3 * Copyright (c) 2008 Ivo van Poorten
4 *
5 * Due to a lack of sample files, only files with one channel are supported.
6 * u-law and ADPCM audio are unsupported for the same reason.
7 *
8 * This file is part of FFmpeg.
9 *
10 * FFmpeg is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Lesser General Public
12 * License as published by the Free Software Foundation; either
13 * version 2.1 of the License, or (at your option) any later version.
14 *
15 * FFmpeg is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * Lesser General Public License for more details.
19 *
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with FFmpeg; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 */
24
26
29
30 #define LMLM4_I_FRAME 0x00
31 #define LMLM4_P_FRAME 0x01
32 #define LMLM4_B_FRAME 0x02
33 #define LMLM4_INVALID 0x03
34 #define LMLM4_MPEG1L2 0x04
35
36 #define LMLM4_MAX_PACKET_SIZE 1024 * 1024
37
39 {
40 const unsigned char *
buf = pd->
buf;
41 unsigned int frame_type, packet_size;
42
45
49 if ((
AV_RB16(buf + 8) & 0xfffe) != 0xfffc)
50 return 0;
51 /* I could calculate the audio framesize and compare with
52 * packet_size-8, but that seems overkill */
54 }
else if (
AV_RB24(buf + 8) == 0x000001) {
/* PES Signal */
56 }
57 }
58
59 return 0;
60 }
61
63 {
65
72
78
79 /* the parameters will be extracted from the compressed bitstream */
80 return 0;
81 }
82
84 {
86 int ret;
87 unsigned int frame_type, packet_size, padding,
frame_size;
88
92 padding = -packet_size & 511;
93 frame_size = packet_size - 8;
94
98 }
102 }
103
106
108
109 switch (frame_type) {
115 break;
118 break;
119 }
120
121 return ret;
122 }
123
130 };
AVInputFormat ff_lmlm4_demuxer
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
unsigned int avio_rb16(AVIOContext *s)
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
unsigned int avio_rb32(AVIOContext *s)
static int lmlm4_read_header(AVFormatContext *s)
enum AVStreamParseType need_parsing
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
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
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
#define LMLM4_MAX_PACKET_SIZE
enum AVMediaType codec_type
General type of the encoded data.
int flags
A combination of AV_PKT_FLAG values.
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
static int lmlm4_probe(AVProbeData *pd)
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_RB24
AVIOContext * pb
I/O context.
This structure contains the data a format has to probe a file.
static int lmlm4_read_packet(AVFormatContext *s, AVPacket *pkt)
AVCodecParameters * codecpar
Codec parameters associated with this stream.
This structure stores compressed data.