repositories / deb_ffmpeg.git / blame
| Commit | Line | Data |
|---|---|---|
| 2ba45a60 DM |
1 | /* |
| 2 | * LOAS AudioSyncStream demuxer | |
| 3 | * Copyright (c) 2008 Michael Niedermayer <michaelni@gmx.at> | |
| 4 | * | |
| 5 | * This file is part of FFmpeg. | |
| 6 | * | |
| 7 | * FFmpeg is free software; you can redistribute it and/or | |
| 8 | * modify it under the terms of the GNU Lesser General Public | |
| 9 | * License as published by the Free Software Foundation; either | |
| 10 | * version 2.1 of the License, or (at your option) any later version. | |
| 11 | * | |
| 12 | * FFmpeg is distributed in the hope that it will be useful, | |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 15 | * Lesser General Public License for more details. | |
| 16 | * | |
| 17 | * You should have received a copy of the GNU Lesser General Public | |
| 18 | * License along with FFmpeg; if not, write to the Free Software | |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
| 20 | */ | |
| 21 | ||
| 22 | #include "libavutil/intreadwrite.h" | |
| 23 | #include "libavutil/internal.h" | |
| 24 | #include "avformat.h" | |
| 25 | #include "internal.h" | |
| 26 | #include "rawdec.h" | |
| 27 | ||
| 28 | #define LOAS_SYNC_WORD 0x2b7 | |
| 29 | ||
| 30 | static int loas_probe(AVProbeData *p) | |
| 31 | { | |
| 32 | int max_frames = 0, first_frames = 0; | |
| 33 | int fsize, frames; | |
| 34 | const uint8_t *buf0 = p->buf; | |
| 35 | const uint8_t *buf2; | |
| 36 | const uint8_t *buf; | |
| 37 | const uint8_t *end = buf0 + p->buf_size - 3; | |
| 38 | buf = buf0; | |
| 39 | ||
| 40 | for (; buf < end; buf = buf2 + 1) { | |
| 41 | buf2 = buf; | |
| 42 | ||
| 43 | for (frames = 0; buf2 < end; frames++) { | |
| 44 | uint32_t header = AV_RB24(buf2); | |
| 45 | if ((header >> 13) != LOAS_SYNC_WORD) | |
| 46 | break; | |
| 47 | fsize = (header & 0x1FFF) + 3; | |
| 48 | if (fsize < 7) | |
| 49 | break; | |
| 50 | fsize = FFMIN(fsize, end - buf2); | |
| 51 | buf2 += fsize; | |
| 52 | } | |
| 53 | max_frames = FFMAX(max_frames, frames); | |
| 54 | if (buf == buf0) | |
| 55 | first_frames = frames; | |
| 56 | } | |
| 57 | ||
| 58 | if (first_frames >= 3) | |
| 59 | return AVPROBE_SCORE_EXTENSION + 1; | |
| 60 | else if (max_frames > 100) | |
| 61 | return AVPROBE_SCORE_EXTENSION; | |
| 62 | else if (max_frames >= 3) | |
| 63 | return AVPROBE_SCORE_EXTENSION / 2; | |
| 64 | else | |
| 65 | return 0; | |
| 66 | } | |
| 67 | ||
| 68 | static int loas_read_header(AVFormatContext *s) | |
| 69 | { | |
| 70 | AVStream *st; | |
| 71 | ||
| 72 | st = avformat_new_stream(s, NULL); | |
| 73 | if (!st) | |
| 74 | return AVERROR(ENOMEM); | |
| 75 | ||
| 76 | st->codec->codec_type = AVMEDIA_TYPE_AUDIO; | |
| 77 | st->codec->codec_id = s->iformat->raw_codec_id; | |
| 78 | st->need_parsing = AVSTREAM_PARSE_FULL_RAW; | |
| 79 | ||
| 80 | //LCM of all possible AAC sample rates | |
| 81 | avpriv_set_pts_info(st, 64, 1, 28224000); | |
| 82 | ||
| 83 | return 0; | |
| 84 | } | |
| 85 | ||
| 86 | AVInputFormat ff_loas_demuxer = { | |
| 87 | .name = "loas", | |
| 88 | .long_name = NULL_IF_CONFIG_SMALL("LOAS AudioSyncStream"), | |
| 89 | .read_probe = loas_probe, | |
| 90 | .read_header = loas_read_header, | |
| 91 | .read_packet = ff_raw_read_partial_packet, | |
| 92 | .flags= AVFMT_GENERIC_INDEX, | |
| 93 | .raw_codec_id = AV_CODEC_ID_AAC_LATM, | |
| 94 | }; |