Commit | Line | Data |
---|---|---|
2ba45a60 DM |
1 | /* |
2 | * MLP codec common header file | |
3 | * Copyright (c) 2007-2008 Ian Caulfield | |
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 | #ifndef AVCODEC_MLP_H | |
23 | #define AVCODEC_MLP_H | |
24 | ||
25 | #include <stdint.h> | |
26 | ||
27 | #include "avcodec.h" | |
28 | ||
29 | /** Last possible matrix channel for each codec */ | |
30 | #define MAX_MATRIX_CHANNEL_MLP 5 | |
31 | #define MAX_MATRIX_CHANNEL_TRUEHD 7 | |
32 | /** Maximum number of channels in a valid stream. | |
33 | * MLP : 5.1 + 2 noise channels -> 8 channels | |
34 | * TrueHD: 7.1 -> 8 channels | |
35 | */ | |
36 | #define MAX_CHANNELS 8 | |
37 | ||
38 | /** Maximum number of matrices used in decoding; most streams have one matrix | |
39 | * per output channel, but some rematrix a channel (usually 0) more than once. | |
40 | */ | |
41 | #define MAX_MATRICES_MLP 6 | |
42 | #define MAX_MATRICES_TRUEHD 8 | |
43 | #define MAX_MATRICES 8 | |
44 | ||
45 | /** Maximum number of substreams that can be decoded. | |
46 | * MLP's limit is 2. TrueHD supports at least up to 3. | |
47 | */ | |
f6fa7814 | 48 | #define MAX_SUBSTREAMS 4 |
2ba45a60 DM |
49 | |
50 | /** which multiple of 48000 the maximum sample rate is */ | |
51 | #define MAX_RATEFACTOR 4 | |
52 | /** maximum sample frequency seen in files */ | |
53 | #define MAX_SAMPLERATE (MAX_RATEFACTOR * 48000) | |
54 | ||
55 | /** maximum number of audio samples within one access unit */ | |
56 | #define MAX_BLOCKSIZE (40 * MAX_RATEFACTOR) | |
57 | /** next power of two greater than MAX_BLOCKSIZE */ | |
58 | #define MAX_BLOCKSIZE_POW2 (64 * MAX_RATEFACTOR) | |
59 | ||
60 | /** number of allowed filters */ | |
61 | #define NUM_FILTERS 2 | |
62 | ||
63 | /** The maximum number of taps in IIR and FIR filters. */ | |
64 | #define MAX_FIR_ORDER 8 | |
65 | #define MAX_IIR_ORDER 4 | |
66 | ||
67 | /** Code that signals end of a stream. */ | |
68 | #define END_OF_STREAM 0xd234d234 | |
69 | ||
70 | #define FIR 0 | |
71 | #define IIR 1 | |
72 | ||
73 | /** filter data */ | |
74 | typedef struct FilterParams { | |
75 | uint8_t order; ///< number of taps in filter | |
76 | uint8_t shift; ///< Right shift to apply to output of filter. | |
77 | ||
78 | int32_t state[MAX_FIR_ORDER]; | |
79 | } FilterParams; | |
80 | ||
81 | /** sample data coding information */ | |
82 | typedef struct ChannelParams { | |
83 | FilterParams filter_params[NUM_FILTERS]; | |
84 | int32_t coeff[NUM_FILTERS][MAX_FIR_ORDER]; | |
85 | ||
86 | int16_t huff_offset; ///< Offset to apply to residual values. | |
87 | int32_t sign_huff_offset; ///< sign/rounding-corrected version of huff_offset | |
88 | uint8_t codebook; ///< Which VLC codebook to use to read residuals. | |
89 | uint8_t huff_lsbs; ///< Size of residual suffix not encoded using VLC. | |
90 | } ChannelParams; | |
91 | ||
92 | /** Tables defining the Huffman codes. | |
93 | * There are three entropy coding methods used in MLP (four if you count | |
94 | * "none" as a method). These use the same sequences for codes starting with | |
95 | * 00 or 01, but have different codes starting with 1. | |
96 | */ | |
97 | extern const uint8_t ff_mlp_huffman_tables[3][18][2]; | |
98 | ||
99 | /** MLP uses checksums that seem to be based on the standard CRC algorithm, but | |
100 | * are not (in implementation terms, the table lookup and XOR are reversed). | |
101 | * We can implement this behavior using a standard av_crc on all but the | |
102 | * last element, then XOR that with the last element. | |
103 | */ | |
104 | uint8_t ff_mlp_checksum8 (const uint8_t *buf, unsigned int buf_size); | |
105 | uint16_t ff_mlp_checksum16(const uint8_t *buf, unsigned int buf_size); | |
106 | ||
107 | /** Calculate an 8-bit checksum over a restart header -- a non-multiple-of-8 | |
108 | * number of bits, starting two bits into the first byte of buf. | |
109 | */ | |
110 | uint8_t ff_mlp_restart_checksum(const uint8_t *buf, unsigned int bit_size); | |
111 | ||
112 | /** XOR together all the bytes of a buffer. | |
113 | * Does this belong in dspcontext? | |
114 | */ | |
115 | uint8_t ff_mlp_calculate_parity(const uint8_t *buf, unsigned int buf_size); | |
116 | ||
117 | void ff_mlp_init_crc(void); | |
118 | ||
119 | /** XOR four bytes into one. */ | |
120 | static inline uint8_t xor_32_to_8(uint32_t value) | |
121 | { | |
122 | value ^= value >> 16; | |
123 | value ^= value >> 8; | |
124 | return value; | |
125 | } | |
126 | ||
127 | typedef enum THDChannelModifier { | |
128 | THD_CH_MODIFIER_NOTINDICATED = 0x0, | |
129 | THD_CH_MODIFIER_STEREO = 0x0, // Stereo (not Dolby Surround) | |
130 | THD_CH_MODIFIER_LTRT = 0x1, // Dolby Surround | |
131 | THD_CH_MODIFIER_LBINRBIN = 0x2, // Dolby Headphone | |
132 | THD_CH_MODIFIER_MONO = 0x3, // Mono or Dual Mono | |
133 | THD_CH_MODIFIER_NOTSURROUNDEX = 0x1, // Not Dolby Digital EX | |
134 | THD_CH_MODIFIER_SURROUNDEX = 0x2, // Dolby Digital EX | |
135 | } THDChannelModifier; | |
136 | ||
137 | #endif /* AVCODEC_MLP_H */ |