mirror of
https://gitee.com/openharmony/third_party_ffmpeg
synced 2024-11-30 14:40:32 +00:00
59f4966756
* commit '86a361081d3eb4e999d75bc2a462f01d88cbd2e5': lmlm4: K&R formatting cosmetics Conflicts: libavformat/lmlm4.c Merged-by: Michael Niedermayer <michaelni@gmx.at>
131 lines
4.0 KiB
C
131 lines
4.0 KiB
C
/*
|
|
* Linux Media Labs MPEG-4 demuxer
|
|
* Copyright (c) 2008 Ivo van Poorten
|
|
*
|
|
* Due to a lack of sample files, only files with one channel are supported.
|
|
* u-law and ADPCM audio are unsupported for the same reason.
|
|
*
|
|
* This file is part of FFmpeg.
|
|
*
|
|
* FFmpeg 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.
|
|
*
|
|
* FFmpeg 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 FFmpeg; 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 "internal.h"
|
|
|
|
#define LMLM4_I_FRAME 0x00
|
|
#define LMLM4_P_FRAME 0x01
|
|
#define LMLM4_B_FRAME 0x02
|
|
#define LMLM4_INVALID 0x03
|
|
#define LMLM4_MPEG1L2 0x04
|
|
|
|
#define LMLM4_MAX_PACKET_SIZE 1024 * 1024
|
|
|
|
static int lmlm4_probe(AVProbeData *pd)
|
|
{
|
|
const unsigned char *buf = pd->buf;
|
|
unsigned int frame_type, packet_size;
|
|
|
|
frame_type = AV_RB16(buf + 2);
|
|
packet_size = AV_RB32(buf + 4);
|
|
|
|
if (!AV_RB16(buf) && frame_type <= LMLM4_MPEG1L2 && packet_size &&
|
|
frame_type != LMLM4_INVALID && packet_size <= LMLM4_MAX_PACKET_SIZE) {
|
|
if (frame_type == LMLM4_MPEG1L2) {
|
|
if ((AV_RB16(buf + 8) & 0xfffe) != 0xfffc)
|
|
return 0;
|
|
/* I could calculate the audio framesize and compare with
|
|
* packet_size-8, but that seems overkill */
|
|
return AVPROBE_SCORE_MAX / 3;
|
|
} else if (AV_RB24(buf + 8) == 0x000001) { /* PES Signal */
|
|
return AVPROBE_SCORE_MAX / 5;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int lmlm4_read_header(AVFormatContext *s)
|
|
{
|
|
AVStream *st;
|
|
|
|
if (!(st = avformat_new_stream(s, NULL)))
|
|
return AVERROR(ENOMEM);
|
|
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
|
|
st->codec->codec_id = AV_CODEC_ID_MPEG4;
|
|
st->need_parsing = AVSTREAM_PARSE_HEADERS;
|
|
avpriv_set_pts_info(st, 64, 1001, 30000);
|
|
|
|
if (!(st = avformat_new_stream(s, NULL)))
|
|
return AVERROR(ENOMEM);
|
|
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
|
|
st->codec->codec_id = AV_CODEC_ID_MP2;
|
|
st->need_parsing = AVSTREAM_PARSE_HEADERS;
|
|
|
|
/* the parameters will be extracted from the compressed bitstream */
|
|
return 0;
|
|
}
|
|
|
|
static int lmlm4_read_packet(AVFormatContext *s, AVPacket *pkt)
|
|
{
|
|
AVIOContext *pb = s->pb;
|
|
int ret;
|
|
unsigned int frame_type, packet_size, padding, frame_size;
|
|
|
|
avio_rb16(pb); /* channel number */
|
|
frame_type = avio_rb16(pb);
|
|
packet_size = avio_rb32(pb);
|
|
padding = -packet_size & 511;
|
|
frame_size = packet_size - 8;
|
|
|
|
if (frame_type > LMLM4_MPEG1L2 || frame_type == LMLM4_INVALID) {
|
|
av_log(s, AV_LOG_ERROR, "invalid or unsupported frame_type\n");
|
|
return AVERROR(EIO);
|
|
}
|
|
if (packet_size > LMLM4_MAX_PACKET_SIZE || packet_size<=8) {
|
|
av_log(s, AV_LOG_ERROR, "packet size %d is invalid\n", packet_size);
|
|
return AVERROR(EIO);
|
|
}
|
|
|
|
if ((ret = av_get_packet(pb, pkt, frame_size)) <= 0)
|
|
return AVERROR(EIO);
|
|
|
|
avio_skip(pb, padding);
|
|
|
|
switch (frame_type) {
|
|
case LMLM4_I_FRAME:
|
|
pkt->flags = AV_PKT_FLAG_KEY;
|
|
case LMLM4_P_FRAME:
|
|
case LMLM4_B_FRAME:
|
|
pkt->stream_index = 0;
|
|
break;
|
|
case LMLM4_MPEG1L2:
|
|
pkt->stream_index = 1;
|
|
break;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
AVInputFormat ff_lmlm4_demuxer = {
|
|
.name = "lmlm4",
|
|
.long_name = NULL_IF_CONFIG_SMALL("raw lmlm4"),
|
|
.read_probe = lmlm4_probe,
|
|
.read_header = lmlm4_read_header,
|
|
.read_packet = lmlm4_read_packet,
|
|
};
|