FFmpeg/libavcodec/opus_parser.c
James Almer 35c84ae834 Revert "avcodec/opus_parser: Handle complete frames flag."
This reverts commit 7e0df5910e.

"complete frames" containers, even if they don't need to assemble
packets, still depended on this code for proper packet duration and
timestamp generation.
2018-08-23 17:34:25 -03:00

199 lines
5.8 KiB
C

/*
* Copyright (c) 2013-2014 Mozilla Corporation
*
* 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
*/
/**
* @file
* Opus parser
*
* Determines the duration for each packet.
*/
#include "avcodec.h"
#include "bytestream.h"
#include "opus.h"
#include "parser.h"
typedef struct OpusParseContext {
ParseContext pc;
OpusContext ctx;
OpusPacket pkt;
int extradata_parsed;
int ts_framing;
} OpusParseContext;
static const uint8_t *parse_opus_ts_header(const uint8_t *start, int *payload_len, int buf_len)
{
const uint8_t *buf = start + 1;
int start_trim_flag, end_trim_flag, control_extension_flag, control_extension_length;
uint8_t flags;
uint64_t payload_len_tmp;
GetByteContext gb;
bytestream2_init(&gb, buf, buf_len);
flags = bytestream2_get_byte(&gb);
start_trim_flag = (flags >> 4) & 1;
end_trim_flag = (flags >> 3) & 1;
control_extension_flag = (flags >> 2) & 1;
payload_len_tmp = *payload_len = 0;
while (bytestream2_peek_byte(&gb) == 0xff)
payload_len_tmp += bytestream2_get_byte(&gb);
payload_len_tmp += bytestream2_get_byte(&gb);
if (start_trim_flag)
bytestream2_skip(&gb, 2);
if (end_trim_flag)
bytestream2_skip(&gb, 2);
if (control_extension_flag) {
control_extension_length = bytestream2_get_byte(&gb);
bytestream2_skip(&gb, control_extension_length);
}
if (bytestream2_tell(&gb) + payload_len_tmp > buf_len)
return NULL;
*payload_len = payload_len_tmp;
return buf + bytestream2_tell(&gb);
}
/**
* Find the end of the current frame in the bitstream.
* @return the position of the first byte of the next frame, or -1
*/
static int opus_find_frame_end(AVCodecParserContext *ctx, AVCodecContext *avctx,
const uint8_t *buf, int buf_size, int *header_len)
{
OpusParseContext *s = ctx->priv_data;
ParseContext *pc = &s->pc;
int ret, start_found, i = 0, payload_len = 0;
const uint8_t *payload;
uint32_t state;
uint16_t hdr;
*header_len = 0;
if (!buf_size)
return 0;
start_found = pc->frame_start_found;
state = pc->state;
payload = buf;
/* Check if we're using Opus in MPEG-TS framing */
if (!s->ts_framing && buf_size > 2) {
hdr = AV_RB16(buf);
if ((hdr & OPUS_TS_MASK) == OPUS_TS_HEADER)
s->ts_framing = 1;
}
if (s->ts_framing && !start_found) {
for (i = 0; i < buf_size-2; i++) {
state = (state << 8) | payload[i];
if ((state & OPUS_TS_MASK) == OPUS_TS_HEADER) {
payload = parse_opus_ts_header(payload, &payload_len, buf_size - i);
if (!payload) {
av_log(avctx, AV_LOG_ERROR, "Error parsing Ogg TS header.\n");
return AVERROR_INVALIDDATA;
}
*header_len = payload - buf;
start_found = 1;
break;
}
}
}
if (!s->ts_framing)
payload_len = buf_size;
if (avctx->extradata && !s->extradata_parsed) {
ret = ff_opus_parse_extradata(avctx, &s->ctx);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR, "Error parsing Ogg extradata.\n");
return AVERROR_INVALIDDATA;
}
av_freep(&s->ctx.channel_maps);
s->extradata_parsed = 1;
}
if (payload_len <= buf_size && (!s->ts_framing || start_found)) {
ret = ff_opus_parse_packet(&s->pkt, payload, payload_len, s->ctx.nb_streams > 1);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR, "Error parsing Opus packet header.\n");
pc->frame_start_found = 0;
return AVERROR_INVALIDDATA;
}
ctx->duration = s->pkt.frame_count * s->pkt.frame_duration;
}
if (s->ts_framing) {
if (start_found) {
if (payload_len + *header_len <= buf_size) {
pc->frame_start_found = 0;
pc->state = -1;
return payload_len + *header_len;
}
}
pc->frame_start_found = start_found;
pc->state = state;
return END_NOT_FOUND;
}
return buf_size;
}
static int opus_parse(AVCodecParserContext *ctx, AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
OpusParseContext *s = ctx->priv_data;
ParseContext *pc = &s->pc;
int next, header_len;
next = opus_find_frame_end(ctx, avctx, buf, buf_size, &header_len);
if (s->ts_framing && next != AVERROR_INVALIDDATA &&
ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
}
if (next == AVERROR_INVALIDDATA){
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
}
*poutbuf = buf + header_len;
*poutbuf_size = buf_size - header_len;
return next;
}
AVCodecParser ff_opus_parser = {
.codec_ids = { AV_CODEC_ID_OPUS },
.priv_data_size = sizeof(OpusParseContext),
.parser_parse = opus_parse,
.parser_close = ff_parse_close
};