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  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24  *
25  */
26 
27 /*
28  * generation options
29  *	CONEX_CAM	Conexant if present
30  */
31 
32 /* JPEG header */
33 static const u8 jpeg_head[] = {
34 	0xff, 0xd8,			/* jpeg */
35 
36 /* quantization table quality 50% */
37 	0xff, 0xdb, 0x00, 0x84,		/* DQT */
38 0,
39 #define JPEG_QT0_OFFSET 7
40 	0x10, 0x0b, 0x0c, 0x0e, 0x0c, 0x0a, 0x10, 0x0e,
41 	0x0d, 0x0e, 0x12, 0x11, 0x10, 0x13, 0x18, 0x28,
42 	0x1a, 0x18, 0x16, 0x16, 0x18, 0x31, 0x23, 0x25,
43 	0x1d, 0x28, 0x3a, 0x33, 0x3d, 0x3c, 0x39, 0x33,
44 	0x38, 0x37, 0x40, 0x48, 0x5c, 0x4e, 0x40, 0x44,
45 	0x57, 0x45, 0x37, 0x38, 0x50, 0x6d, 0x51, 0x57,
46 	0x5f, 0x62, 0x67, 0x68, 0x67, 0x3e, 0x4d, 0x71,
47 	0x79, 0x70, 0x64, 0x78, 0x5c, 0x65, 0x67, 0x63,
48 1,
49 #define JPEG_QT1_OFFSET 72
50 	0x11, 0x12, 0x12, 0x18, 0x15, 0x18, 0x2f, 0x1a,
51 	0x1a, 0x2f, 0x63, 0x42, 0x38, 0x42, 0x63, 0x63,
52 	0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
53 	0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
54 	0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
55 	0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
56 	0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
57 	0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
58 
59 /* huffman table */
60 	0xff, 0xc4, 0x01, 0xa2,
61 	0x00, 0x00, 0x01, 0x05, 0x01, 0x01, 0x01, 0x01,
62 	0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
63 	0x00, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
64 	0x07, 0x08, 0x09, 0x0a, 0x0b, 0x01, 0x00, 0x03,
65 	0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
66 	0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
67 	0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
68 	0x0a, 0x0b, 0x10, 0x00, 0x02, 0x01, 0x03, 0x03,
69 	0x02, 0x04, 0x03, 0x05, 0x05, 0x04, 0x04, 0x00,
70 	0x00, 0x01, 0x7d, 0x01, 0x02, 0x03, 0x00, 0x04,
71 	0x11, 0x05, 0x12, 0x21, 0x31, 0x41, 0x06, 0x13,
72 	0x51, 0x61, 0x07, 0x22, 0x71, 0x14, 0x32, 0x81,
73 	0x91, 0xa1, 0x08, 0x23, 0x42, 0xb1, 0xc1, 0x15,
74 	0x52, 0xd1, 0xf0, 0x24, 0x33, 0x62, 0x72, 0x82,
75 	0x09, 0x0a, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x25,
76 	0x26, 0x27, 0x28, 0x29, 0x2a, 0x34, 0x35, 0x36,
77 	0x37, 0x38, 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46,
78 	0x47, 0x48, 0x49, 0x4a, 0x53, 0x54, 0x55, 0x56,
79 	0x57, 0x58, 0x59, 0x5a, 0x63, 0x64, 0x65, 0x66,
80 	0x67, 0x68, 0x69, 0x6a, 0x73, 0x74, 0x75, 0x76,
81 	0x77, 0x78, 0x79, 0x7a, 0x83, 0x84, 0x85, 0x86,
82 	0x87, 0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95,
83 	0x96, 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4,
84 	0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3,
85 	0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2,
86 	0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca,
87 	0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9,
88 	0xda, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
89 	0xe8, 0xe9, 0xea, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5,
90 	0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0x11, 0x00, 0x02,
91 	0x01, 0x02, 0x04, 0x04, 0x03, 0x04, 0x07, 0x05,
92 	0x04, 0x04, 0x00, 0x01, 0x02, 0x77, 0x00, 0x01,
93 	0x02, 0x03, 0x11, 0x04, 0x05, 0x21, 0x31, 0x06,
94 	0x12, 0x41, 0x51, 0x07, 0x61, 0x71, 0x13, 0x22,
95 	0x32, 0x81, 0x08, 0x14, 0x42, 0x91, 0xa1, 0xb1,
96 	0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0, 0x15, 0x62,
97 	0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34, 0xe1, 0x25,
98 	0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26, 0x27, 0x28,
99 	0x29, 0x2a, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a,
100 	0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a,
101 	0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a,
102 	0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a,
103 	0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a,
104 	0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
105 	0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,
106 	0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
107 	0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,
108 	0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,
109 	0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,
110 	0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe2, 0xe3,
111 	0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xf2,
112 	0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa,
113 #ifdef CONEX_CAM
114 /* the Conexant frames start with SOF0 */
115 #define JPEG_HDR_SZ 556
116 #else
117 	0xff, 0xc0, 0x00, 0x11,		/* SOF0 (start of frame 0 */
118 	0x08,				/* data precision */
119 #define JPEG_HEIGHT_OFFSET 561
120 	0x01, 0xe0,			/* height */
121 	0x02, 0x80,			/* width */
122 	0x03,				/* component number */
123 		0x01,
124 			0x21,		/* samples Y */
125 			0x00,		/* quant Y */
126 		0x02, 0x11, 0x01,	/* samples CbCr - quant CbCr */
127 		0x03, 0x11, 0x01,
128 
129 	0xff, 0xda, 0x00, 0x0c,		/* SOS (start of scan) */
130 	0x03, 0x01, 0x00, 0x02, 0x11, 0x03, 0x11, 0x00, 0x3f, 0x00
131 #define JPEG_HDR_SZ 589
132 #endif
133 };
134 
135 /* define the JPEG header */
jpeg_define(u8 * jpeg_hdr,int height,int width,int samplesY)136 static void jpeg_define(u8 *jpeg_hdr,
137 			int height,
138 			int width,
139 			int samplesY)
140 {
141 	memcpy(jpeg_hdr, jpeg_head, sizeof jpeg_head);
142 #ifndef CONEX_CAM
143 	jpeg_hdr[JPEG_HEIGHT_OFFSET + 0] = height >> 8;
144 	jpeg_hdr[JPEG_HEIGHT_OFFSET + 1] = height;
145 	jpeg_hdr[JPEG_HEIGHT_OFFSET + 2] = width >> 8;
146 	jpeg_hdr[JPEG_HEIGHT_OFFSET + 3] = width;
147 	jpeg_hdr[JPEG_HEIGHT_OFFSET + 6] = samplesY;
148 #endif
149 }
150 
151 /* set the JPEG quality */
jpeg_set_qual(u8 * jpeg_hdr,int quality)152 static void jpeg_set_qual(u8 *jpeg_hdr,
153 			  int quality)
154 {
155 	int i, sc;
156 
157 	if (quality < 50)
158 		sc = 5000 / quality;
159 	else
160 		sc = 200 - quality * 2;
161 	for (i = 0; i < 64; i++) {
162 		jpeg_hdr[JPEG_QT0_OFFSET + i] =
163 			(jpeg_head[JPEG_QT0_OFFSET + i] * sc + 50) / 100;
164 		jpeg_hdr[JPEG_QT1_OFFSET + i] =
165 			(jpeg_head[JPEG_QT1_OFFSET + i] * sc + 50) / 100;
166 	}
167 }
168 #endif
169