1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
2 | #ifndef JPEG_H |
3 | #define JPEG_H 1 |
4 | /* |
5 | * Insert a JPEG header at start of frame |
6 | * |
7 | * This module is used by the gspca subdrivers. |
8 | * A special case is done for Conexant webcams. |
9 | * |
10 | * Copyright (C) Jean-Francois Moine (http://moinejf.free.fr) |
11 | */ |
12 | |
13 | /* |
14 | * generation options |
15 | * CONEX_CAM Conexant if present |
16 | */ |
17 | |
18 | /* JPEG header */ |
19 | static const u8 jpeg_head[] = { |
20 | 0xff, 0xd8, /* jpeg */ |
21 | |
22 | /* quantization table quality 50% */ |
23 | 0xff, 0xdb, 0x00, 0x84, /* DQT */ |
24 | 0, |
25 | #define JPEG_QT0_OFFSET 7 |
26 | 0x10, 0x0b, 0x0c, 0x0e, 0x0c, 0x0a, 0x10, 0x0e, |
27 | 0x0d, 0x0e, 0x12, 0x11, 0x10, 0x13, 0x18, 0x28, |
28 | 0x1a, 0x18, 0x16, 0x16, 0x18, 0x31, 0x23, 0x25, |
29 | 0x1d, 0x28, 0x3a, 0x33, 0x3d, 0x3c, 0x39, 0x33, |
30 | 0x38, 0x37, 0x40, 0x48, 0x5c, 0x4e, 0x40, 0x44, |
31 | 0x57, 0x45, 0x37, 0x38, 0x50, 0x6d, 0x51, 0x57, |
32 | 0x5f, 0x62, 0x67, 0x68, 0x67, 0x3e, 0x4d, 0x71, |
33 | 0x79, 0x70, 0x64, 0x78, 0x5c, 0x65, 0x67, 0x63, |
34 | 1, |
35 | #define JPEG_QT1_OFFSET 72 |
36 | 0x11, 0x12, 0x12, 0x18, 0x15, 0x18, 0x2f, 0x1a, |
37 | 0x1a, 0x2f, 0x63, 0x42, 0x38, 0x42, 0x63, 0x63, |
38 | 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, |
39 | 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, |
40 | 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, |
41 | 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, |
42 | 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, |
43 | 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, |
44 | |
45 | /* huffman table */ |
46 | 0xff, 0xc4, 0x01, 0xa2, |
47 | 0x00, 0x00, 0x01, 0x05, 0x01, 0x01, 0x01, 0x01, |
48 | 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
49 | 0x00, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, |
50 | 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x01, 0x00, 0x03, |
51 | 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, |
52 | 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, |
53 | 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, |
54 | 0x0a, 0x0b, 0x10, 0x00, 0x02, 0x01, 0x03, 0x03, |
55 | 0x02, 0x04, 0x03, 0x05, 0x05, 0x04, 0x04, 0x00, |
56 | 0x00, 0x01, 0x7d, 0x01, 0x02, 0x03, 0x00, 0x04, |
57 | 0x11, 0x05, 0x12, 0x21, 0x31, 0x41, 0x06, 0x13, |
58 | 0x51, 0x61, 0x07, 0x22, 0x71, 0x14, 0x32, 0x81, |
59 | 0x91, 0xa1, 0x08, 0x23, 0x42, 0xb1, 0xc1, 0x15, |
60 | 0x52, 0xd1, 0xf0, 0x24, 0x33, 0x62, 0x72, 0x82, |
61 | 0x09, 0x0a, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x25, |
62 | 0x26, 0x27, 0x28, 0x29, 0x2a, 0x34, 0x35, 0x36, |
63 | 0x37, 0x38, 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, |
64 | 0x47, 0x48, 0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, |
65 | 0x57, 0x58, 0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, |
66 | 0x67, 0x68, 0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, |
67 | 0x77, 0x78, 0x79, 0x7a, 0x83, 0x84, 0x85, 0x86, |
68 | 0x87, 0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, |
69 | 0x96, 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, |
70 | 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, |
71 | 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, |
72 | 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, |
73 | 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, |
74 | 0xda, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, |
75 | 0xe8, 0xe9, 0xea, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, |
76 | 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0x11, 0x00, 0x02, |
77 | 0x01, 0x02, 0x04, 0x04, 0x03, 0x04, 0x07, 0x05, |
78 | 0x04, 0x04, 0x00, 0x01, 0x02, 0x77, 0x00, 0x01, |
79 | 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, 0x31, 0x06, |
80 | 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, 0x13, 0x22, |
81 | 0x32, 0x81, 0x08, 0x14, 0x42, 0x91, 0xa1, 0xb1, |
82 | 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0, 0x15, 0x62, |
83 | 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34, 0xe1, 0x25, |
84 | 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26, 0x27, 0x28, |
85 | 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, |
86 | 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, |
87 | 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, |
88 | 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, |
89 | 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, |
90 | 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, |
91 | 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, |
92 | 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, |
93 | 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, |
94 | 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5, |
95 | 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4, |
96 | 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe2, 0xe3, |
97 | 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xf2, |
98 | 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, |
99 | #ifdef CONEX_CAM |
100 | /* the Conexant frames start with SOF0 */ |
101 | #define JPEG_HDR_SZ 556 |
102 | #else |
103 | 0xff, 0xc0, 0x00, 0x11, /* SOF0 (start of frame 0 */ |
104 | 0x08, /* data precision */ |
105 | #define JPEG_HEIGHT_OFFSET 561 |
106 | 0x01, 0xe0, /* height */ |
107 | 0x02, 0x80, /* width */ |
108 | 0x03, /* component number */ |
109 | 0x01, |
110 | 0x21, /* samples Y */ |
111 | 0x00, /* quant Y */ |
112 | 0x02, 0x11, 0x01, /* samples CbCr - quant CbCr */ |
113 | 0x03, 0x11, 0x01, |
114 | |
115 | 0xff, 0xda, 0x00, 0x0c, /* SOS (start of scan) */ |
116 | 0x03, 0x01, 0x00, 0x02, 0x11, 0x03, 0x11, 0x00, 0x3f, 0x00 |
117 | #define JPEG_HDR_SZ 589 |
118 | #endif |
119 | }; |
120 | |
121 | /* define the JPEG header */ |
122 | static void jpeg_define(u8 *jpeg_hdr, |
123 | int height, |
124 | int width, |
125 | int samplesY) |
126 | { |
127 | memcpy(jpeg_hdr, jpeg_head, sizeof jpeg_head); |
128 | #ifndef CONEX_CAM |
129 | jpeg_hdr[JPEG_HEIGHT_OFFSET + 0] = height >> 8; |
130 | jpeg_hdr[JPEG_HEIGHT_OFFSET + 1] = height; |
131 | jpeg_hdr[JPEG_HEIGHT_OFFSET + 2] = width >> 8; |
132 | jpeg_hdr[JPEG_HEIGHT_OFFSET + 3] = width; |
133 | jpeg_hdr[JPEG_HEIGHT_OFFSET + 6] = samplesY; |
134 | #endif |
135 | } |
136 | |
137 | /* set the JPEG quality */ |
138 | static void jpeg_set_qual(u8 *jpeg_hdr, |
139 | int quality) |
140 | { |
141 | int i, sc; |
142 | |
143 | if (quality <= 0) |
144 | sc = 5000; |
145 | else if (quality < 50) |
146 | sc = 5000 / quality; |
147 | else |
148 | sc = 200 - quality * 2; |
149 | for (i = 0; i < 64; i++) { |
150 | jpeg_hdr[JPEG_QT0_OFFSET + i] = |
151 | (jpeg_head[JPEG_QT0_OFFSET + i] * sc + 50) / 100; |
152 | jpeg_hdr[JPEG_QT1_OFFSET + i] = |
153 | (jpeg_head[JPEG_QT1_OFFSET + i] * sc + 50) / 100; |
154 | } |
155 | } |
156 | #endif |
157 | |