Libav
mlp.h
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1 /*
2  * MLP codec common header file
3  * Copyright (c) 2007-2008 Ian Caulfield
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; 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 
30 #define MAX_MATRIX_CHANNEL_MLP 5
31 #define MAX_MATRIX_CHANNEL_TRUEHD 7
32 
36 #define MAX_CHANNELS 8
37 
41 #define MAX_MATRICES_MLP 6
42 #define MAX_MATRICES_TRUEHD 8
43 #define MAX_MATRICES 8
44 
48 #define MAX_SUBSTREAMS 3
49 
51 #define MAX_RATEFACTOR 4
52 
53 #define MAX_SAMPLERATE (MAX_RATEFACTOR * 48000)
54 
56 #define MAX_BLOCKSIZE (40 * MAX_RATEFACTOR)
57 
58 #define MAX_BLOCKSIZE_POW2 (64 * MAX_RATEFACTOR)
59 
61 #define NUM_FILTERS 2
62 
64 #define MAX_FIR_ORDER 8
65 #define MAX_IIR_ORDER 4
66 
68 #define END_OF_STREAM 0xd234d234
69 
70 #define FIR 0
71 #define IIR 1
72 
74 typedef struct FilterParams {
77 
79 } FilterParams;
80 
82 typedef struct ChannelParams {
83  FilterParams filter_params[NUM_FILTERS];
85 
86  int16_t huff_offset;
91 
97 extern const uint8_t ff_mlp_huffman_tables[3][18][2];
98 
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 
110 uint8_t ff_mlp_restart_checksum(const uint8_t *buf, unsigned int bit_size);
111 
115 uint8_t ff_mlp_calculate_parity(const uint8_t *buf, unsigned int buf_size);
116 
117 void ff_mlp_init_crc(void);
118 
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 {
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
136 
137 #endif /* AVCODEC_MLP_H */
uint8_t shift
Right shift to apply to output of filter.
Definition: mlp.h:76
uint16_t ff_mlp_checksum16(const uint8_t *buf, unsigned int buf_size)
Definition: mlp.c:64
uint8_t
static uint8_t xor_32_to_8(uint32_t value)
XOR four bytes into one.
Definition: mlp.h:120
#define MAX_FIR_ORDER
The maximum number of taps in IIR and FIR filters.
Definition: mlp.h:64
const uint8_t ff_mlp_huffman_tables[3][18][2]
Tables defining the Huffman codes.
Definition: mlp.c:28
uint8_t ff_mlp_calculate_parity(const uint8_t *buf, unsigned int buf_size)
XOR together all the bytes of a buffer.
Definition: mlp.c:99
THDChannelModifier
Definition: mlp.h:127
int16_t huff_offset
Offset to apply to residual values.
Definition: mlp.h:86
#define NUM_FILTERS
number of allowed filters
Definition: mlp.h:61
uint8_t ff_mlp_checksum8(const uint8_t *buf, unsigned int buf_size)
MLP uses checksums that seem to be based on the standard CRC algorithm, but are not (in implementatio...
Definition: mlp.c:73
void ff_mlp_init_crc(void)
Definition: mlp.c:54
int32_t
uint8_t codebook
Which VLC codebook to use to read residuals.
Definition: mlp.h:88
Libavcodec external API header.
int32_t state[MAX_FIR_ORDER]
Definition: mlp.h:78
uint8_t order
number of taps in filter
Definition: mlp.h:75
filter data
Definition: mlp.h:74
uint8_t huff_lsbs
Size of residual suffix not encoded using VLC.
Definition: mlp.h:89
sample data coding information
Definition: mlp.h:82
uint8_t ff_mlp_restart_checksum(const uint8_t *buf, unsigned int bit_size)
Calculate an 8-bit checksum over a restart header – a non-multiple-of-8 number of bits...
Definition: mlp.c:80
int32_t sign_huff_offset
sign/rounding-corrected version of huff_offset
Definition: mlp.h:87