blob: 42fcdf75c39bce51b6604c2f833d059e6fe49b91
| 1 | /* |
| 2 | * Shorten demuxer |
| 3 | * Copyright (c) 2001 Fabrice Bellard |
| 4 | * Copyright (c) 2005 Alex Beregszaszi |
| 5 | * Copyright (c) 2015 Carl Eugen Hoyos |
| 6 | * |
| 7 | * This file is part of FFmpeg. |
| 8 | * |
| 9 | * FFmpeg is free software; you can redistribute it and/or |
| 10 | * modify it under the terms of the GNU Lesser General Public |
| 11 | * License as published by the Free Software Foundation; either |
| 12 | * version 2.1 of the License, or (at your option) any later version. |
| 13 | * |
| 14 | * FFmpeg is distributed in the hope that it will be useful, |
| 15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 17 | * Lesser General Public License for more details. |
| 18 | * |
| 19 | * You should have received a copy of the GNU Lesser General Public |
| 20 | * License along with FFmpeg; if not, write to the Free Software |
| 21 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 22 | */ |
| 23 | |
| 24 | #include "avformat.h" |
| 25 | #include "rawdec.h" |
| 26 | #include "libavcodec/golomb.h" |
| 27 | |
| 28 | static int shn_probe(AVProbeData *p) |
| 29 | { |
| 30 | GetBitContext gb; |
| 31 | int version, internal_ftype, channels, blocksize; |
| 32 | |
| 33 | if (AV_RB32(p->buf) != 0x616a6b67) |
| 34 | return 0; |
| 35 | version = p->buf[4]; |
| 36 | if (init_get_bits8(&gb, p->buf + 5, p->buf_size - 5 - AV_INPUT_BUFFER_PADDING_SIZE) < 0) |
| 37 | return 0; |
| 38 | if (!version) { |
| 39 | internal_ftype = get_ur_golomb_shorten(&gb, 4); |
| 40 | channels = get_ur_golomb_shorten(&gb, 0); |
| 41 | blocksize = 256; |
| 42 | } else { |
| 43 | int k; |
| 44 | k = get_ur_golomb_shorten(&gb, 2); |
| 45 | internal_ftype = get_ur_golomb_shorten(&gb, k); |
| 46 | k = get_ur_golomb_shorten(&gb, 2); |
| 47 | channels = get_ur_golomb_shorten(&gb, k); |
| 48 | k = get_ur_golomb_shorten(&gb, 2); |
| 49 | blocksize = get_ur_golomb_shorten(&gb, k); |
| 50 | } |
| 51 | |
| 52 | if (internal_ftype != 2 && internal_ftype != 3 && internal_ftype != 5) |
| 53 | return 0; |
| 54 | if (channels < 1 || channels > 8) |
| 55 | return 0; |
| 56 | if (blocksize < 1 || blocksize > 65535) |
| 57 | return 0; |
| 58 | |
| 59 | return AVPROBE_SCORE_EXTENSION + 1; |
| 60 | } |
| 61 | |
| 62 | AVInputFormat ff_shorten_demuxer = { |
| 63 | .name = "shn", |
| 64 | .long_name = NULL_IF_CONFIG_SMALL("raw Shorten"), |
| 65 | .read_probe = shn_probe, |
| 66 | .read_header = ff_raw_audio_read_header, |
| 67 | .read_packet = ff_raw_read_partial_packet, |
| 68 | .flags = AVFMT_NOBINSEARCH | AVFMT_NOGENSEARCH | AVFMT_NO_BYTE_SEEK | AVFMT_NOTIMESTAMPS, |
| 69 | .extensions = "shn", |
| 70 | .raw_codec_id = AV_CODEC_ID_SHORTEN, |
| 71 | }; |
| 72 |