LCOV - code coverage report
Current view: top level - libavcodec - opus_parser.c (source / functions) Hit Total Coverage
Test: coverage.info Lines: 68 89 76.4 %
Date: 2018-02-20 21:25:12 Functions: 3 3 100.0 %

          Line data    Source code
       1             : /*
       2             :  * Copyright (c) 2013-2014 Mozilla Corporation
       3             :  *
       4             :  * This file is part of FFmpeg.
       5             :  *
       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.
      10             :  *
      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.
      15             :  *
      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
      19             :  */
      20             : 
      21             : /**
      22             :  * @file
      23             :  * Opus parser
      24             :  *
      25             :  * Determines the duration for each packet.
      26             :  */
      27             : 
      28             : #include "avcodec.h"
      29             : #include "bytestream.h"
      30             : #include "opus.h"
      31             : #include "parser.h"
      32             : 
      33             : typedef struct OpusParseContext {
      34             :     ParseContext pc;
      35             :     OpusContext ctx;
      36             :     OpusPacket pkt;
      37             :     int extradata_parsed;
      38             :     int ts_framing;
      39             : } OpusParseContext;
      40             : 
      41         765 : static const uint8_t *parse_opus_ts_header(const uint8_t *start, int *payload_len, int buf_len)
      42             : {
      43         765 :     const uint8_t *buf = start + 1;
      44             :     int start_trim_flag, end_trim_flag, control_extension_flag, control_extension_length;
      45             :     uint8_t flags;
      46             :     uint64_t payload_len_tmp;
      47             : 
      48             :     GetByteContext gb;
      49         765 :     bytestream2_init(&gb, buf, buf_len);
      50             : 
      51         765 :     flags = bytestream2_get_byte(&gb);
      52         765 :     start_trim_flag        = (flags >> 4) & 1;
      53         765 :     end_trim_flag          = (flags >> 3) & 1;
      54         765 :     control_extension_flag = (flags >> 2) & 1;
      55             : 
      56         765 :     payload_len_tmp = *payload_len = 0;
      57        3694 :     while (bytestream2_peek_byte(&gb) == 0xff)
      58        2164 :         payload_len_tmp += bytestream2_get_byte(&gb);
      59             : 
      60         765 :     payload_len_tmp += bytestream2_get_byte(&gb);
      61             : 
      62         765 :     if (start_trim_flag)
      63           0 :         bytestream2_skip(&gb, 2);
      64         765 :     if (end_trim_flag)
      65           0 :         bytestream2_skip(&gb, 2);
      66         765 :     if (control_extension_flag) {
      67           0 :         control_extension_length = bytestream2_get_byte(&gb);
      68           0 :         bytestream2_skip(&gb, control_extension_length);
      69             :     }
      70             : 
      71         765 :     if (bytestream2_tell(&gb) + payload_len_tmp > buf_len)
      72           0 :         return NULL;
      73             : 
      74         765 :     *payload_len = payload_len_tmp;
      75             : 
      76         765 :     return buf + bytestream2_tell(&gb);
      77             : }
      78             : 
      79             : /**
      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
      82             :  */
      83       22671 : static int opus_find_frame_end(AVCodecParserContext *ctx, AVCodecContext *avctx,
      84             :                                const uint8_t *buf, int buf_size, int *header_len)
      85             : {
      86       22671 :     OpusParseContext *s = ctx->priv_data;
      87       22671 :     ParseContext *pc    = &s->pc;
      88       22671 :     int ret, start_found, i = 0, payload_len = 0;
      89             :     const uint8_t *payload;
      90             :     uint32_t state;
      91             :     uint16_t hdr;
      92       22671 :     *header_len = 0;
      93             : 
      94       22671 :     if (!buf_size)
      95          19 :         return 0;
      96             : 
      97       22652 :     start_found = pc->frame_start_found;
      98       22652 :     state = pc->state;
      99       22652 :     payload = buf;
     100             : 
     101             :     /* Check if we're using Opus in MPEG-TS framing */
     102       22652 :     if (!s->ts_framing && buf_size > 2) {
     103       21889 :         hdr = AV_RB16(buf);
     104       21889 :         if ((hdr & OPUS_TS_MASK) == OPUS_TS_HEADER)
     105           2 :             s->ts_framing = 1;
     106             :     }
     107             : 
     108       22652 :     if (s->ts_framing && !start_found) {
     109        1530 :         for (i = 0; i < buf_size-2; i++) {
     110        1530 :             state = (state << 8) | payload[i];
     111        1530 :             if ((state & OPUS_TS_MASK) == OPUS_TS_HEADER) {
     112         765 :                 payload = parse_opus_ts_header(payload, &payload_len, buf_size - i);
     113         765 :                 if (!payload) {
     114           0 :                     av_log(avctx, AV_LOG_ERROR, "Error parsing Ogg TS header.\n");
     115           0 :                     return AVERROR_INVALIDDATA;
     116             :                 }
     117         765 :                 *header_len = payload - buf;
     118         765 :                 start_found = 1;
     119         765 :                 break;
     120             :             }
     121             :         }
     122             :     }
     123             : 
     124       22652 :     if (!s->ts_framing)
     125       21887 :         payload_len = buf_size;
     126             : 
     127       22652 :     if (avctx->extradata && !s->extradata_parsed) {
     128          42 :         ret = ff_opus_parse_extradata(avctx, &s->ctx);
     129          42 :         if (ret < 0) {
     130           0 :             av_log(avctx, AV_LOG_ERROR, "Error parsing Ogg extradata.\n");
     131           0 :             return AVERROR_INVALIDDATA;
     132             :         }
     133          42 :         av_freep(&s->ctx.channel_maps);
     134          42 :         s->extradata_parsed = 1;
     135             :     }
     136             : 
     137       22652 :     if (payload_len <= buf_size && (!s->ts_framing || start_found)) {
     138       22652 :         ret = ff_opus_parse_packet(&s->pkt, payload, payload_len, s->ctx.nb_streams > 1);
     139       22652 :         if (ret < 0) {
     140           0 :             av_log(avctx, AV_LOG_ERROR, "Error parsing Opus packet header.\n");
     141           0 :             pc->frame_start_found = 0;
     142           0 :             return AVERROR_INVALIDDATA;
     143             :         }
     144             : 
     145       22652 :         ctx->duration = s->pkt.frame_count * s->pkt.frame_duration;
     146             :     }
     147             : 
     148       22652 :     if (s->ts_framing) {
     149         765 :         if (start_found) {
     150         765 :             if (payload_len + *header_len <= buf_size) {
     151         765 :                 pc->frame_start_found = 0;
     152         765 :                 pc->state             = -1;
     153         765 :                 return payload_len + *header_len;
     154             :             }
     155             :         }
     156             : 
     157           0 :         pc->frame_start_found = start_found;
     158           0 :         pc->state = state;
     159           0 :         return END_NOT_FOUND;
     160             :     }
     161             : 
     162       21887 :     return buf_size;
     163             : }
     164             : 
     165       22671 : static int opus_parse(AVCodecParserContext *ctx, AVCodecContext *avctx,
     166             :                        const uint8_t **poutbuf, int *poutbuf_size,
     167             :                        const uint8_t *buf, int buf_size)
     168             : {
     169       22671 :     OpusParseContext *s = ctx->priv_data;
     170       22671 :     ParseContext *pc    = &s->pc;
     171             :     int next, header_len;
     172             : 
     173       22671 :     next = opus_find_frame_end(ctx, avctx, buf, buf_size, &header_len);
     174             : 
     175       23437 :     if (s->ts_framing && next != AVERROR_INVALIDDATA &&
     176         766 :         ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
     177           0 :         *poutbuf      = NULL;
     178           0 :         *poutbuf_size = 0;
     179           0 :         return buf_size;
     180             :     }
     181             : 
     182       22671 :     if (next == AVERROR_INVALIDDATA){
     183           0 :         *poutbuf      = NULL;
     184           0 :         *poutbuf_size = 0;
     185           0 :         return buf_size;
     186             :     }
     187             : 
     188       22671 :     *poutbuf      = buf + header_len;
     189       22671 :     *poutbuf_size = buf_size - header_len;
     190       22671 :     return next;
     191             : }
     192             : 
     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
     198             : };

Generated by: LCOV version 1.13