FFmpeg
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mjpeg.c
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1 /*
2  * MJPEG encoder and decoder
3  * Copyright (c) 2000, 2001 Fabrice Bellard
4  * Copyright (c) 2003 Alex Beregszaszi
5  * Copyright (c) 2003-2004 Michael Niedermayer
6  *
7  * Support for external huffman table, various fixes (AVID workaround),
8  * aspecting, new decode_frame mechanism and apple mjpeg-b support
9  * by Alex Beregszaszi
10  *
11  * This file is part of FFmpeg.
12  *
13  * FFmpeg is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU Lesser General Public
15  * License as published by the Free Software Foundation; either
16  * version 2.1 of the License, or (at your option) any later version.
17  *
18  * FFmpeg is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21  * Lesser General Public License for more details.
22  *
23  * You should have received a copy of the GNU Lesser General Public
24  * License along with FFmpeg; if not, write to the Free Software
25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26  */
27 
28 /**
29  * @file
30  * MJPEG encoder and decoder.
31  */
32 
33 #include "mjpeg.h"
34 
35 
36 #if 0
37 /* These are the sample quantization tables given in JPEG spec section K.1.
38  * The spec says that the values given produce "good" quality, and
39  * when divided by 2, "very good" quality.
40  */
41 const unsigned char std_luminance_quant_tbl[64] = {
42  16, 11, 10, 16, 24, 40, 51, 61,
43  12, 12, 14, 19, 26, 58, 60, 55,
44  14, 13, 16, 24, 40, 57, 69, 56,
45  14, 17, 22, 29, 51, 87, 80, 62,
46  18, 22, 37, 56, 68, 109, 103, 77,
47  24, 35, 55, 64, 81, 104, 113, 92,
48  49, 64, 78, 87, 103, 121, 120, 101,
49  72, 92, 95, 98, 112, 100, 103, 99
50 };
51 const unsigned char std_chrominance_quant_tbl[64] = {
52  17, 18, 24, 47, 99, 99, 99, 99,
53  18, 21, 26, 66, 99, 99, 99, 99,
54  24, 26, 56, 99, 99, 99, 99, 99,
55  47, 66, 99, 99, 99, 99, 99, 99,
56  99, 99, 99, 99, 99, 99, 99, 99,
57  99, 99, 99, 99, 99, 99, 99, 99,
58  99, 99, 99, 99, 99, 99, 99, 99,
59  99, 99, 99, 99, 99, 99, 99, 99
60 };
61 #endif
62 
63 /* Set up the standard Huffman tables (cf. JPEG standard section K.3) */
64 /* IMPORTANT: these are only valid for 8-bit data precision! */
66 { /* 0-base */ 0, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0 };
68 { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };
69 
71 { /* 0-base */ 0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0 };
72 
74 { /* 0-base */ 0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d };
76 { 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,
77  0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07,
78  0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08,
79  0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0,
80  0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16,
81  0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28,
82  0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
83  0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,
84  0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
85  0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
86  0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,
87  0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
88  0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,
89  0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
90  0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,
91  0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,
92  0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,
93  0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,
94  0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea,
95  0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
96  0xf9, 0xfa
97 };
98 
100 { /* 0-base */ 0, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77 };
101 
103 { 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21,
104  0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71,
105  0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91,
106  0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0,
107  0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34,
108  0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26,
109  0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38,
110  0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,
111  0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
112  0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
113  0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
114  0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
115  0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96,
116  0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5,
117  0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4,
118  0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,
119  0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2,
120  0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,
121  0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,
122  0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
123  0xf9, 0xfa
124 };
125 
126 /* isn't this function nicer than the one in the libjpeg ? */
127 void ff_mjpeg_build_huffman_codes(uint8_t *huff_size, uint16_t *huff_code,
128  const uint8_t *bits_table,
129  const uint8_t *val_table)
130 {
131  int i, j, k,nb, code, sym;
132 
133  code = 0;
134  k = 0;
135  for(i=1;i<=16;i++) {
136  nb = bits_table[i];
137  for(j=0;j<nb;j++) {
138  sym = val_table[k++];
139  huff_size[sym] = i;
140  huff_code[sym] = code;
141  code++;
142  }
143  code <<= 1;
144  }
145 }