1 #ifndef JPEG_H
2 #define JPEG_H 1
3 /*
4 * Insert a JPEG header at start of frame
5 *
6 * This module is used by the gspca subdrivers.
7 * A special case is done for Conexant webcams.
8 *
9 * Copyright (C) Jean-Francois Moine (http://moinejf.free.fr)
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 */
22
23 /*
24 * generation options
25 * CONEX_CAM Conexant if present
26 */
27
28 /* JPEG header */
29 static const u8 jpeg_head[] = {
30 0xff, 0xd8, /* jpeg */
31
32 /* quantization table quality 50% */
33 0xff, 0xdb, 0x00, 0x84, /* DQT */
34 0,
35 #define JPEG_QT0_OFFSET 7
36 0x10, 0x0b, 0x0c, 0x0e, 0x0c, 0x0a, 0x10, 0x0e,
37 0x0d, 0x0e, 0x12, 0x11, 0x10, 0x13, 0x18, 0x28,
38 0x1a, 0x18, 0x16, 0x16, 0x18, 0x31, 0x23, 0x25,
39 0x1d, 0x28, 0x3a, 0x33, 0x3d, 0x3c, 0x39, 0x33,
40 0x38, 0x37, 0x40, 0x48, 0x5c, 0x4e, 0x40, 0x44,
41 0x57, 0x45, 0x37, 0x38, 0x50, 0x6d, 0x51, 0x57,
42 0x5f, 0x62, 0x67, 0x68, 0x67, 0x3e, 0x4d, 0x71,
43 0x79, 0x70, 0x64, 0x78, 0x5c, 0x65, 0x67, 0x63,
44 1,
45 #define JPEG_QT1_OFFSET 72
46 0x11, 0x12, 0x12, 0x18, 0x15, 0x18, 0x2f, 0x1a,
47 0x1a, 0x2f, 0x63, 0x42, 0x38, 0x42, 0x63, 0x63,
48 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
49 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
50 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
51 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
52 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
53 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
54
55 /* huffman table */
56 0xff, 0xc4, 0x01, 0xa2,
57 0x00, 0x00, 0x01, 0x05, 0x01, 0x01, 0x01, 0x01,
58 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
59 0x00, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
60 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x01, 0x00, 0x03,
61 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
62 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
63 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
64 0x0a, 0x0b, 0x10, 0x00, 0x02, 0x01, 0x03, 0x03,
65 0x02, 0x04, 0x03, 0x05, 0x05, 0x04, 0x04, 0x00,
66 0x00, 0x01, 0x7d, 0x01, 0x02, 0x03, 0x00, 0x04,
67 0x11, 0x05, 0x12, 0x21, 0x31, 0x41, 0x06, 0x13,
68 0x51, 0x61, 0x07, 0x22, 0x71, 0x14, 0x32, 0x81,
69 0x91, 0xa1, 0x08, 0x23, 0x42, 0xb1, 0xc1, 0x15,
70 0x52, 0xd1, 0xf0, 0x24, 0x33, 0x62, 0x72, 0x82,
71 0x09, 0x0a, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x25,
72 0x26, 0x27, 0x28, 0x29, 0x2a, 0x34, 0x35, 0x36,
73 0x37, 0x38, 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46,
74 0x47, 0x48, 0x49, 0x4a, 0x53, 0x54, 0x55, 0x56,
75 0x57, 0x58, 0x59, 0x5a, 0x63, 0x64, 0x65, 0x66,
76 0x67, 0x68, 0x69, 0x6a, 0x73, 0x74, 0x75, 0x76,
77 0x77, 0x78, 0x79, 0x7a, 0x83, 0x84, 0x85, 0x86,
78 0x87, 0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95,
79 0x96, 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4,
80 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3,
81 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2,
82 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca,
83 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9,
84 0xda, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
85 0xe8, 0xe9, 0xea, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5,
86 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0x11, 0x00, 0x02,
87 0x01, 0x02, 0x04, 0x04, 0x03, 0x04, 0x07, 0x05,
88 0x04, 0x04, 0x00, 0x01, 0x02, 0x77, 0x00, 0x01,
89 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, 0x31, 0x06,
90 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, 0x13, 0x22,
91 0x32, 0x81, 0x08, 0x14, 0x42, 0x91, 0xa1, 0xb1,
92 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0, 0x15, 0x62,
93 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34, 0xe1, 0x25,
94 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26, 0x27, 0x28,
95 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a,
96 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a,
97 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a,
98 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a,
99 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a,
100 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
101 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,
102 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
103 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,
104 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,
105 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,
106 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe2, 0xe3,
107 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xf2,
108 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa,
109 #ifdef CONEX_CAM
110 /* the Conexant frames start with SOF0 */
111 #define JPEG_HDR_SZ 556
112 #else
113 0xff, 0xc0, 0x00, 0x11, /* SOF0 (start of frame 0 */
114 0x08, /* data precision */
115 #define JPEG_HEIGHT_OFFSET 561
116 0x01, 0xe0, /* height */
117 0x02, 0x80, /* width */
118 0x03, /* component number */
119 0x01,
120 0x21, /* samples Y */
121 0x00, /* quant Y */
122 0x02, 0x11, 0x01, /* samples CbCr - quant CbCr */
123 0x03, 0x11, 0x01,
124
125 0xff, 0xda, 0x00, 0x0c, /* SOS (start of scan) */
126 0x03, 0x01, 0x00, 0x02, 0x11, 0x03, 0x11, 0x00, 0x3f, 0x00
127 #define JPEG_HDR_SZ 589
128 #endif
129 };
130
131 /* define the JPEG header */
jpeg_define(u8 * jpeg_hdr,int height,int width,int samplesY)132 static void jpeg_define(u8 *jpeg_hdr,
133 int height,
134 int width,
135 int samplesY)
136 {
137 memcpy(jpeg_hdr, jpeg_head, sizeof jpeg_head);
138 #ifndef CONEX_CAM
139 jpeg_hdr[JPEG_HEIGHT_OFFSET + 0] = height >> 8;
140 jpeg_hdr[JPEG_HEIGHT_OFFSET + 1] = height;
141 jpeg_hdr[JPEG_HEIGHT_OFFSET + 2] = width >> 8;
142 jpeg_hdr[JPEG_HEIGHT_OFFSET + 3] = width;
143 jpeg_hdr[JPEG_HEIGHT_OFFSET + 6] = samplesY;
144 #endif
145 }
146
147 /* set the JPEG quality */
jpeg_set_qual(u8 * jpeg_hdr,int quality)148 static void jpeg_set_qual(u8 *jpeg_hdr,
149 int quality)
150 {
151 int i, sc;
152
153 if (quality <= 0)
154 sc = 5000;
155 else if (quality < 50)
156 sc = 5000 / quality;
157 else
158 sc = 200 - quality * 2;
159 for (i = 0; i < 64; i++) {
160 jpeg_hdr[JPEG_QT0_OFFSET + i] =
161 (jpeg_head[JPEG_QT0_OFFSET + i] * sc + 50) / 100;
162 jpeg_hdr[JPEG_QT1_OFFSET + i] =
163 (jpeg_head[JPEG_QT1_OFFSET + i] * sc + 50) / 100;
164 }
165 }
166 #endif
167
