2 * Copyright (c) 2013-2014 Mozilla Corporation
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 * Determines the duration for each packet.
29 #include "bytestream.h"
33 typedef struct OpusParseContext {
41 static const uint8_t *parse_opus_ts_header(const uint8_t *start, int *payload_len, int buf_len)
43 const uint8_t *buf = start + 1;
44 int start_trim_flag, end_trim_flag, control_extension_flag, control_extension_length;
46 uint64_t payload_len_tmp;
49 bytestream2_init(&gb, buf, buf_len);
51 flags = bytestream2_get_byte(&gb);
52 start_trim_flag = (flags >> 4) & 1;
53 end_trim_flag = (flags >> 3) & 1;
54 control_extension_flag = (flags >> 2) & 1;
56 payload_len_tmp = *payload_len = 0;
57 while (bytestream2_peek_byte(&gb) == 0xff)
58 payload_len_tmp += bytestream2_get_byte(&gb);
60 payload_len_tmp += bytestream2_get_byte(&gb);
63 bytestream2_skip(&gb, 2);
65 bytestream2_skip(&gb, 2);
66 if (control_extension_flag) {
67 control_extension_length = bytestream2_get_byte(&gb);
68 bytestream2_skip(&gb, control_extension_length);
71 if (bytestream2_tell(&gb) + payload_len_tmp > buf_len)
74 *payload_len = payload_len_tmp;
76 return buf + bytestream2_tell(&gb);
80 * Find the end of the current frame in the bitstream.
81 * @return the position of the first byte of the next frame, or -1
83 static int opus_find_frame_end(AVCodecParserContext *ctx, AVCodecContext *avctx,
84 const uint8_t *buf, int buf_size, int *header_len)
86 OpusParseContext *s = ctx->priv_data;
87 ParseContext *pc = &s->pc;
88 int ret, start_found, i = 0, payload_len = 0;
89 const uint8_t *payload;
97 start_found = pc->frame_start_found;
101 /* Check if we're using Opus in MPEG-TS framing */
102 if (!s->ts_framing && buf_size > 2) {
104 if ((hdr & OPUS_TS_MASK) == OPUS_TS_HEADER)
108 if (s->ts_framing && !start_found) {
109 for (i = 0; i < buf_size-2; i++) {
110 state = (state << 8) | payload[i];
111 if ((state & OPUS_TS_MASK) == OPUS_TS_HEADER) {
112 payload = parse_opus_ts_header(payload, &payload_len, buf_size - i);
114 av_log(avctx, AV_LOG_ERROR, "Error parsing Ogg TS header.\n");
115 return AVERROR_INVALIDDATA;
117 *header_len = payload - buf;
125 payload_len = buf_size;
127 if (avctx->extradata && !s->extradata_parsed) {
128 ret = ff_opus_parse_extradata(avctx, &s->ctx);
130 av_log(avctx, AV_LOG_ERROR, "Error parsing Ogg extradata.\n");
131 return AVERROR_INVALIDDATA;
133 av_freep(&s->ctx.channel_maps);
134 s->extradata_parsed = 1;
137 if (payload_len <= buf_size && (!s->ts_framing || start_found)) {
138 ret = ff_opus_parse_packet(&s->pkt, payload, payload_len, s->ctx.nb_streams > 1);
140 av_log(avctx, AV_LOG_ERROR, "Error parsing Opus packet header.\n");
141 pc->frame_start_found = 0;
142 return AVERROR_INVALIDDATA;
145 ctx->duration = s->pkt.frame_count * s->pkt.frame_duration;
150 if (payload_len + *header_len <= buf_size) {
151 pc->frame_start_found = 0;
153 return payload_len + *header_len;
157 pc->frame_start_found = start_found;
159 return END_NOT_FOUND;
165 static int opus_parse(AVCodecParserContext *ctx, AVCodecContext *avctx,
166 const uint8_t **poutbuf, int *poutbuf_size,
167 const uint8_t *buf, int buf_size)
169 OpusParseContext *s = ctx->priv_data;
170 ParseContext *pc = &s->pc;
171 int next, header_len;
173 next = opus_find_frame_end(ctx, avctx, buf, buf_size, &header_len);
175 if (s->ts_framing && next != AVERROR_INVALIDDATA &&
176 ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
182 if (next == AVERROR_INVALIDDATA){
188 *poutbuf = buf + header_len;
189 *poutbuf_size = buf_size - header_len;
193 AVCodecParser ff_opus_parser = {
194 .codec_ids = { AV_CODEC_ID_OPUS },
195 .priv_data_size = sizeof(OpusParseContext),
196 .parser_parse = opus_parse,
197 .parser_close = ff_parse_close