1 /*
2 * MLP codec common code
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 #include <stdint.h>
23
24 #include "libavutil/channel_layout.h"
25 #include "libavutil/crc.h"
26 #include "libavutil/intreadwrite.h"
27 #include "libavutil/thread.h"
28 #include "mlp.h"
29
30 const uint8_t ff_mlp_huffman_tables[3][18][2] = {
31 { /* Huffman table 0, -7 - +10 */
32 {0x01, 9}, {0x01, 8}, {0x01, 7}, {0x01, 6}, {0x01, 5}, {0x01, 4}, {0x01, 3},
33 {0x04, 3}, {0x05, 3}, {0x06, 3}, {0x07, 3},
34 {0x03, 3}, {0x05, 4}, {0x09, 5}, {0x11, 6}, {0x21, 7}, {0x41, 8}, {0x81, 9},
35 }, { /* Huffman table 1, -7 - +8 */
36 {0x01, 9}, {0x01, 8}, {0x01, 7}, {0x01, 6}, {0x01, 5}, {0x01, 4}, {0x01, 3},
37 {0x02, 2}, {0x03, 2},
38 {0x03, 3}, {0x05, 4}, {0x09, 5}, {0x11, 6}, {0x21, 7}, {0x41, 8}, {0x81, 9},
39 }, { /* Huffman table 2, -7 - +7 */
40 {0x01, 9}, {0x01, 8}, {0x01, 7}, {0x01, 6}, {0x01, 5}, {0x01, 4}, {0x01, 3},
41 {0x01, 1},
42 {0x03, 3}, {0x05, 4}, {0x09, 5}, {0x11, 6}, {0x21, 7}, {0x41, 8}, {0x81, 9},
43 }
44 };
45
46 const ChannelInformation ff_mlp_ch_info[21] = {
47 { 0x01, 0x01, 0x00, 0x1f }, { 0x03, 0x02, 0x00, 0x1b },
48 { 0x07, 0x02, 0x01, 0x1f }, { 0x0F, 0x02, 0x02, 0x19 },
49 { 0x07, 0x02, 0x01, 0x03 }, { 0x0F, 0x02, 0x02, 0x1f },
50 { 0x1F, 0x02, 0x03, 0x01 }, { 0x07, 0x02, 0x01, 0x1a },
51 { 0x0F, 0x02, 0x02, 0x1f }, { 0x1F, 0x02, 0x03, 0x18 },
52 { 0x0F, 0x02, 0x02, 0x02 }, { 0x1F, 0x02, 0x03, 0x1f },
53 { 0x3F, 0x02, 0x04, 0x00 }, { 0x0F, 0x03, 0x01, 0x1f },
54 { 0x1F, 0x03, 0x02, 0x18 }, { 0x0F, 0x03, 0x01, 0x02 },
55 { 0x1F, 0x03, 0x02, 0x1f }, { 0x3F, 0x03, 0x03, 0x00 },
56 { 0x1F, 0x04, 0x01, 0x01 }, { 0x1F, 0x04, 0x01, 0x18 },
57 { 0x3F, 0x04, 0x02, 0x00 },
58 };
59
60 #if FF_API_OLD_CHANNEL_LAYOUT
61 const uint64_t ff_mlp_channel_layouts[12] = {
62 AV_CH_LAYOUT_MONO, AV_CH_LAYOUT_STEREO, AV_CH_LAYOUT_2_1,
63 AV_CH_LAYOUT_QUAD, AV_CH_LAYOUT_2POINT1, AV_CH_LAYOUT_SURROUND,
64 AV_CH_LAYOUT_4POINT0, AV_CH_LAYOUT_5POINT0_BACK, AV_CH_LAYOUT_3POINT1,
65 AV_CH_LAYOUT_4POINT1, AV_CH_LAYOUT_5POINT1_BACK, 0,
66 };
67 #endif
68
69 const AVChannelLayout ff_mlp_ch_layouts[12] = {
70 AV_CHANNEL_LAYOUT_MONO, AV_CHANNEL_LAYOUT_STEREO, AV_CHANNEL_LAYOUT_2_1,
71 AV_CHANNEL_LAYOUT_QUAD, AV_CHANNEL_LAYOUT_2POINT1, AV_CHANNEL_LAYOUT_SURROUND,
72 AV_CHANNEL_LAYOUT_4POINT0, AV_CHANNEL_LAYOUT_5POINT0_BACK, AV_CHANNEL_LAYOUT_3POINT1,
73 AV_CHANNEL_LAYOUT_4POINT1, AV_CHANNEL_LAYOUT_5POINT1_BACK, { 0 },
74 };
75
76 #if CONFIG_SMALL
77 #define CRC_TABLE_SIZE 257
78 #else
79 #define CRC_TABLE_SIZE 1024
80 #endif
81 static AVCRC crc_63[CRC_TABLE_SIZE];
82 static AVCRC crc_1D[CRC_TABLE_SIZE];
83 static AVCRC crc_2D[CRC_TABLE_SIZE];
84
mlp_init_crc(void)85 static av_cold void mlp_init_crc(void)
86 {
87 av_crc_init(crc_63, 0, 8, 0x63, sizeof(crc_63));
88 av_crc_init(crc_1D, 0, 8, 0x1D, sizeof(crc_1D));
89 av_crc_init(crc_2D, 0, 16, 0x002D, sizeof(crc_2D));
90 }
91
ff_mlp_init_crc(void)92 av_cold void ff_mlp_init_crc(void)
93 {
94 static AVOnce init_static_once = AV_ONCE_INIT;
95 ff_thread_once(&init_static_once, mlp_init_crc);
96 }
97
ff_mlp_checksum16(const uint8_t *buf, unsigned int buf_size)98 uint16_t ff_mlp_checksum16(const uint8_t *buf, unsigned int buf_size)
99 {
100 uint16_t crc;
101
102 crc = av_crc(crc_2D, 0, buf, buf_size - 2);
103 crc ^= AV_RL16(buf + buf_size - 2);
104 return crc;
105 }
106
ff_mlp_checksum8(const uint8_t *buf, unsigned int buf_size)107 uint8_t ff_mlp_checksum8(const uint8_t *buf, unsigned int buf_size)
108 {
109 uint8_t checksum = av_crc(crc_63, 0x3c, buf, buf_size - 1); // crc_63[0xa2] == 0x3c
110 checksum ^= buf[buf_size-1];
111 return checksum;
112 }
113
ff_mlp_restart_checksum(const uint8_t *buf, unsigned int bit_size)114 uint8_t ff_mlp_restart_checksum(const uint8_t *buf, unsigned int bit_size)
115 {
116 int i;
117 int num_bytes = (bit_size + 2) / 8;
118
119 int crc = crc_1D[buf[0] & 0x3f];
120 crc = av_crc(crc_1D, crc, buf + 1, num_bytes - 2);
121 crc ^= buf[num_bytes - 1];
122
123 for (i = 0; i < ((bit_size + 2) & 7); i++) {
124 crc <<= 1;
125 if (crc & 0x100)
126 crc ^= 0x11D;
127 crc ^= (buf[num_bytes] >> (7 - i)) & 1;
128 }
129
130 return crc;
131 }
132
ff_mlp_calculate_parity(const uint8_t *buf, unsigned int buf_size)133 uint8_t ff_mlp_calculate_parity(const uint8_t *buf, unsigned int buf_size)
134 {
135 uint32_t scratch = 0;
136 const uint8_t *buf_end = buf + buf_size;
137
138 for (; ((intptr_t) buf & 3) && buf < buf_end; buf++)
139 scratch ^= *buf;
140 for (; buf < buf_end - 3; buf += 4)
141 scratch ^= *((const uint32_t*)buf);
142
143 scratch = xor_32_to_8(scratch);
144
145 for (; buf < buf_end; buf++)
146 scratch ^= *buf;
147
148 return scratch;
149 }
150