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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 6147 | serge | 1 | /* |
| 2 | * RAW DTS demuxer |
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| 3 | * Copyright (c) 2008 Benjamin Larsson |
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| 4 | * |
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| 5 | * This file is part of FFmpeg. |
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| 6 | * |
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| 7 | * FFmpeg is free software; you can redistribute it and/or |
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| 8 | * modify it under the terms of the GNU Lesser General Public |
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| 9 | * License as published by the Free Software Foundation; either |
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| 10 | * version 2.1 of the License, or (at your option) any later version. |
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| 11 | * |
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| 12 | * FFmpeg is distributed in the hope that it will be useful, |
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| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 15 | * Lesser General Public License for more details. |
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| 16 | * |
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| 17 | * You should have received a copy of the GNU Lesser General Public |
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| 18 | * License along with FFmpeg; if not, write to the Free Software |
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| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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| 20 | */ |
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| 21 | |||
| 22 | #include "libavcodec/bytestream.h" |
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| 23 | #include "libavcodec/dca.h" |
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| 24 | #include "libavcodec/dca_syncwords.h" |
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| 25 | #include "libavcodec/get_bits.h" |
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| 26 | |||
| 27 | #include "avformat.h" |
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| 28 | #include "rawdec.h" |
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| 29 | |||
| 30 | static int dts_probe(AVProbeData *p) |
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| 31 | { |
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| 32 | const uint8_t *buf, *bufp; |
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| 33 | uint32_t state = -1; |
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| 34 | int markers[4*16] = {0}; |
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| 35 | int sum, max, i; |
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| 36 | int64_t diff = 0; |
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| 37 | uint8_t hdr[12 + AV_INPUT_BUFFER_PADDING_SIZE] = { 0 }; |
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| 38 | |||
| 39 | buf = p->buf + FFMIN(4096, p->buf_size); |
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| 40 | |||
| 41 | for(; buf < (p->buf+p->buf_size)-2; buf+=2) { |
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| 42 | int marker, sample_blocks, sample_rate, sr_code, framesize; |
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| 43 | int lfe; |
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| 44 | GetBitContext gb; |
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| 45 | |||
| 46 | bufp = buf; |
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| 47 | state = (state << 16) | bytestream_get_be16(&bufp); |
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| 48 | |||
| 49 | if (buf - p->buf >= 4) |
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| 50 | diff += FFABS(((int16_t)AV_RL16(buf)) - (int16_t)AV_RL16(buf-4)); |
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| 51 | |||
| 52 | /* regular bitstream */ |
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| 53 | if (state == DCA_SYNCWORD_CORE_BE && |
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| 54 | (bytestream_get_be16(&bufp) & 0xFC00) == 0xFC00) |
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| 55 | marker = 0; |
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| 56 | else if (state == DCA_SYNCWORD_CORE_LE && |
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| 57 | (bytestream_get_be16(&bufp) & 0x00FC) == 0x00FC) |
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| 58 | marker = 1; |
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| 59 | |||
| 60 | /* 14 bits big-endian bitstream */ |
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| 61 | else if (state == DCA_SYNCWORD_CORE_14B_BE && |
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| 62 | (bytestream_get_be16(&bufp) & 0xFFF0) == 0x07F0) |
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| 63 | marker = 2; |
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| 64 | |||
| 65 | /* 14 bits little-endian bitstream */ |
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| 66 | else if (state == DCA_SYNCWORD_CORE_14B_LE && |
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| 67 | (bytestream_get_be16(&bufp) & 0xF0FF) == 0xF007) |
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| 68 | marker = 3; |
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| 69 | else |
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| 70 | continue; |
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| 71 | |||
| 72 | if (avpriv_dca_convert_bitstream(buf-2, 12, hdr, 12) < 0) |
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| 73 | continue; |
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| 74 | |||
| 75 | init_get_bits(&gb, hdr, 96); |
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| 76 | skip_bits_long(&gb, 39); |
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| 77 | |||
| 78 | sample_blocks = get_bits(&gb, 7) + 1; |
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| 79 | if (sample_blocks < 8) |
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| 80 | continue; |
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| 81 | |||
| 82 | framesize = get_bits(&gb, 14) + 1; |
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| 83 | if (framesize < 95) |
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| 84 | continue; |
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| 85 | |||
| 86 | skip_bits(&gb, 6); |
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| 87 | sr_code = get_bits(&gb, 4); |
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| 88 | sample_rate = avpriv_dca_sample_rates[sr_code]; |
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| 89 | if (sample_rate == 0) |
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| 90 | continue; |
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| 91 | |||
| 92 | get_bits(&gb, 5); |
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| 93 | if (get_bits(&gb, 1)) |
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| 94 | continue; |
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| 95 | |||
| 96 | skip_bits_long(&gb, 9); |
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| 97 | lfe = get_bits(&gb, 2); |
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| 98 | if (lfe > 2) |
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| 99 | continue; |
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| 100 | |||
| 101 | marker += 4* sr_code; |
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| 102 | |||
| 103 | markers[marker] ++; |
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| 104 | } |
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| 105 | |||
| 106 | sum = max = 0; |
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| 107 | for (i=0; i |
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| 108 | sum += markers[i]; |
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| 109 | if (markers[max] < markers[i]) |
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| 110 | max = i; |
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| 111 | } |
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| 112 | |||
| 113 | if (markers[max] > 3 && p->buf_size / markers[max] < 32*1024 && |
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| 114 | markers[max] * 4 > sum * 3 && |
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| 115 | diff / p->buf_size > 200) |
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| 116 | return AVPROBE_SCORE_EXTENSION + 1; |
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| 117 | |||
| 118 | return 0; |
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| 119 | } |
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| 120 | |||
| 121 | AVInputFormat ff_dts_demuxer = { |
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| 122 | .name = "dts", |
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| 123 | .long_name = NULL_IF_CONFIG_SMALL("raw DTS"), |
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| 124 | .read_probe = dts_probe, |
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| 125 | .read_header = ff_raw_audio_read_header, |
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| 126 | .read_packet = ff_raw_read_partial_packet, |
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| 127 | .flags = AVFMT_GENERIC_INDEX, |
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| 128 | .extensions = "dts", |
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| 129 | .raw_codec_id = AV_CODEC_ID_DTS, |
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| 130 | }; |