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 */
19static const u8 jpeg_head[] = {
20	0xff, 0xd8,			/* jpeg */
21
22/* quantization table quality 50% */
23	0xff, 0xdb, 0x00, 0x84,		/* DQT */
240,
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,
341,
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 */
122static 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 */
138static 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