LXR linux/drivers/media/usb/gspca/jpeg.h

   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