diff options
Diffstat (limited to 'libavformat/ac3dec.c')
| -rw-r--r-- | libavformat/ac3dec.c | 68 |
1 files changed, 35 insertions, 33 deletions
diff --git a/libavformat/ac3dec.c b/libavformat/ac3dec.c index 4ceffa5..3db2339 100644 --- a/libavformat/ac3dec.c +++ b/libavformat/ac3dec.c @@ -2,20 +2,20 @@ * RAW AC-3 and E-AC-3 demuxer * Copyright (c) 2007 Justin Ruggles <justin.ruggles@gmail.com> * - * This file is part of Libav. + * This file is part of FFmpeg. * - * Libav is free software; you can redistribute it and/or + * 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. * - * Libav is distributed in the hope that it will be useful, + * 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 Libav; if not, write to the Free Software + * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -27,7 +27,7 @@ static int ac3_eac3_probe(AVProbeData *p, enum AVCodecID expected_codec_id) { int max_frames, first_frames = 0, frames; - uint8_t *buf, *buf2, *end; + const uint8_t *buf, *buf2, *end; AC3HeaderInfo hdr; GetBitContext gbc; enum AVCodecID codec_id = AV_CODEC_ID_AC3; @@ -37,14 +37,36 @@ static int ac3_eac3_probe(AVProbeData *p, enum AVCodecID expected_codec_id) end = buf + p->buf_size; for(; buf < end; buf++) { + if(buf > p->buf && !(buf[0] == 0x0B && buf[1] == 0x77) + && !(buf[0] == 0x77 && buf[1] == 0x0B) ) + continue; buf2 = buf; for(frames = 0; buf2 < end; frames++) { - init_get_bits(&gbc, buf2, 54); + uint8_t buf3[4096]; + int i; + if(!memcmp(buf2, "\x1\x10\0\0\0\0\0\0", 8)) + buf2+=16; + if (buf[0] == 0x77 && buf[1] == 0x0B) { + for(i=0; i<8; i+=2) { + buf3[i ] = buf[i+1]; + buf3[i+1] = buf[i ]; + } + init_get_bits(&gbc, buf3, 54); + }else + init_get_bits(&gbc, buf2, 54); if(avpriv_ac3_parse_header(&gbc, &hdr) < 0) break; - if(buf2 + hdr.frame_size > end || - av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0, buf2 + 2, hdr.frame_size - 2)) + if(buf2 + hdr.frame_size > end) + break; + if (buf[0] == 0x77 && buf[1] == 0x0B) { + av_assert0(hdr.frame_size <= sizeof(buf3)); + for(i=8; i<hdr.frame_size; i+=2) { + buf3[i ] = buf[i+1]; + buf3[i+1] = buf[i ]; + } + } + if(av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0, gbc.buffer + 2, hdr.frame_size - 2)) break; if (hdr.bitstream_id > 10) codec_id = AV_CODEC_ID_EAC3; @@ -57,31 +79,11 @@ static int ac3_eac3_probe(AVProbeData *p, enum AVCodecID expected_codec_id) if(codec_id != expected_codec_id) return 0; // keep this in sync with mp3 probe, both need to avoid // issues with MPEG-files! - if (first_frames >= 4) return AVPROBE_SCORE_EXTENSION + 1; - - if (max_frames) { - int pes = 0, i; - unsigned int code = -1; - -#define VIDEO_ID 0x000001e0 -#define AUDIO_ID 0x000001c0 - /* do a search for mpegps headers to be able to properly bias - * towards mpegps if we detect this stream as both. */ - for (i = 0; i<p->buf_size; i++) { - code = (code << 8) + p->buf[i]; - if ((code & 0xffffff00) == 0x100) { - if ((code & 0x1f0) == VIDEO_ID) pes++; - else if((code & 0x1e0) == AUDIO_ID) pes++; - } - } - - if (pes) - max_frames = (max_frames + pes - 1) / pes; - } - if (max_frames > 500) return AVPROBE_SCORE_EXTENSION; - else if (max_frames >= 4) return AVPROBE_SCORE_EXTENSION / 2; - else if (max_frames >= 1) return 1; - else return 0; + if (first_frames>=4) return AVPROBE_SCORE_EXTENSION + 1; + else if(max_frames>200)return AVPROBE_SCORE_EXTENSION; + else if(max_frames>=4) return AVPROBE_SCORE_EXTENSION/2; + else if(max_frames>=1) return 1; + else return 0; } #if CONFIG_AC3_DEMUXER |
