ffmpeg/libavcodec/adx_parser.c

105 lines
3.3 KiB
C

/*
* Copyright (c) 2011 Justin Ruggles
*
* 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
*/
/**
* @file
* ADX audio parser
*
* Reads header to extradata and splits packets into individual blocks.
*/
#include "libavutil/intreadwrite.h"
#include "parser.h"
#include "adx.h"
typedef struct ADXParseContext {
ParseContext pc;
int header_size;
int block_size;
int buf_pos;
} ADXParseContext;
#define MIN_HEADER_SIZE 24
static int adx_parse(AVCodecParserContext *s1,
AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
ADXParseContext *s = s1->priv_data;
ParseContext *pc = &s->pc;
int next = END_NOT_FOUND;
if (!avctx->extradata_size) {
int ret;
ff_combine_frame(pc, END_NOT_FOUND, &buf, &buf_size);
if (!s->header_size && pc->index >= MIN_HEADER_SIZE) {
if (ret = ff_adx_decode_header(avctx, pc->buffer, pc->index,
&s->header_size, NULL))
return AVERROR_INVALIDDATA;
s->block_size = BLOCK_SIZE * avctx->channels;
}
if (s->header_size && s->header_size <= pc->index) {
avctx->extradata = av_mallocz(s->header_size + FF_INPUT_BUFFER_PADDING_SIZE);
if (!avctx->extradata)
return AVERROR(ENOMEM);
avctx->extradata_size = s->header_size;
memcpy(avctx->extradata, pc->buffer, s->header_size);
memmove(pc->buffer, pc->buffer + s->header_size, s->header_size);
pc->index -= s->header_size;
}
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
}
if (pc->index - s->buf_pos >= s->block_size) {
*poutbuf = &pc->buffer[s->buf_pos];
*poutbuf_size = s->block_size;
s->buf_pos += s->block_size;
return 0;
}
if (pc->index && s->buf_pos) {
memmove(pc->buffer, &pc->buffer[s->buf_pos], pc->index - s->buf_pos);
pc->index -= s->buf_pos;
s->buf_pos = 0;
}
if (buf_size + pc->index >= s->block_size)
next = s->block_size - pc->index;
if (ff_combine_frame(pc, next, &buf, &buf_size) < 0 || !buf_size) {
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
}
*poutbuf = buf;
*poutbuf_size = buf_size;
return next;
}
AVCodecParser ff_adx_parser = {
.codec_ids = { CODEC_ID_ADPCM_ADX },
.priv_data_size = sizeof(ADXParseContext),
.parser_parse = adx_parse,
.parser_close = ff_parse_close,
};