mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-11-26 19:01:44 +02:00
125 lines
3.9 KiB
C
125 lines
3.9 KiB
C
/*
|
|
* SBC parser
|
|
*
|
|
* Copyright (C) 2017 Aurelien Jacobs <aurel@gnuage.org>
|
|
*
|
|
* 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 "sbc.h"
|
|
#include "parser.h"
|
|
|
|
typedef struct SBCParseContext {
|
|
ParseContext pc;
|
|
uint8_t header[3];
|
|
int header_size;
|
|
int buffered_size;
|
|
} SBCParseContext;
|
|
|
|
static int sbc_parse_header(AVCodecParserContext *s, AVCodecContext *avctx,
|
|
const uint8_t *data, size_t len)
|
|
{
|
|
static const int sample_rates[4] = { 16000, 32000, 44100, 48000 };
|
|
int sr, blocks, mode, subbands, bitpool, channels, joint;
|
|
int length;
|
|
|
|
if (len < 3)
|
|
return -1;
|
|
|
|
if (data[0] == MSBC_SYNCWORD && data[1] == 0 && data[2] == 0) {
|
|
av_channel_layout_uninit(&avctx->ch_layout);
|
|
avctx->ch_layout.order = AV_CHANNEL_ORDER_UNSPEC;
|
|
avctx->ch_layout.nb_channels = 1;
|
|
avctx->sample_rate = 16000;
|
|
avctx->frame_size = 120;
|
|
s->duration = avctx->frame_size;
|
|
return 57;
|
|
}
|
|
|
|
if (data[0] != SBC_SYNCWORD)
|
|
return -2;
|
|
|
|
sr = (data[1] >> 6) & 0x03;
|
|
blocks = (((data[1] >> 4) & 0x03) + 1) << 2;
|
|
mode = (data[1] >> 2) & 0x03;
|
|
subbands = (((data[1] >> 0) & 0x01) + 1) << 2;
|
|
bitpool = data[2];
|
|
|
|
channels = mode == SBC_MODE_MONO ? 1 : 2;
|
|
joint = mode == SBC_MODE_JOINT_STEREO;
|
|
|
|
length = 4 + (subbands * channels) / 2
|
|
+ ((((mode == SBC_MODE_DUAL_CHANNEL) + 1) * blocks * bitpool
|
|
+ (joint * subbands)) + 7) / 8;
|
|
|
|
av_channel_layout_uninit(&avctx->ch_layout);
|
|
avctx->ch_layout.order = AV_CHANNEL_ORDER_UNSPEC;
|
|
avctx->ch_layout.nb_channels = channels;
|
|
avctx->sample_rate = sample_rates[sr];
|
|
avctx->frame_size = subbands * blocks;
|
|
s->duration = avctx->frame_size;
|
|
return length;
|
|
}
|
|
|
|
static int sbc_parse(AVCodecParserContext *s, AVCodecContext *avctx,
|
|
const uint8_t **poutbuf, int *poutbuf_size,
|
|
const uint8_t *buf, int buf_size)
|
|
{
|
|
SBCParseContext *pc = s->priv_data;
|
|
int next;
|
|
|
|
if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
|
|
next = buf_size;
|
|
} else {
|
|
if (pc->header_size) {
|
|
memcpy(pc->header + pc->header_size, buf,
|
|
sizeof(pc->header) - pc->header_size);
|
|
next = sbc_parse_header(s, avctx, pc->header, sizeof(pc->header))
|
|
- pc->buffered_size;
|
|
pc->header_size = 0;
|
|
} else {
|
|
next = sbc_parse_header(s, avctx, buf, buf_size);
|
|
if (next >= buf_size)
|
|
next = -1;
|
|
}
|
|
|
|
if (next < 0) {
|
|
pc->header_size = FFMIN(sizeof(pc->header), buf_size);
|
|
memcpy(pc->header, buf, pc->header_size);
|
|
pc->buffered_size = buf_size;
|
|
next = END_NOT_FOUND;
|
|
}
|
|
|
|
if (ff_combine_frame(&pc->pc, next, &buf, &buf_size) < 0) {
|
|
*poutbuf = NULL;
|
|
*poutbuf_size = 0;
|
|
return buf_size;
|
|
}
|
|
}
|
|
|
|
*poutbuf = buf;
|
|
*poutbuf_size = buf_size;
|
|
return next;
|
|
}
|
|
|
|
const AVCodecParser ff_sbc_parser = {
|
|
.codec_ids = { AV_CODEC_ID_SBC },
|
|
.priv_data_size = sizeof(SBCParseContext),
|
|
.parser_parse = sbc_parse,
|
|
.parser_close = ff_parse_close,
|
|
};
|