jpeg.h 5.9 KB

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  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. * generation options
  28. * CONEX_CAM Conexant if present
  29. */
  30. /* JPEG header */
  31. static const u8 jpeg_head[] = {
  32. 0xff, 0xd8, /* jpeg */
  33. /* quantization table quality 50% */
  34. 0xff, 0xdb, 0x00, 0x84, /* DQT */
  35. 0,
  36. #define JPEG_QT0_OFFSET 7
  37. 0x10, 0x0b, 0x0c, 0x0e, 0x0c, 0x0a, 0x10, 0x0e,
  38. 0x0d, 0x0e, 0x12, 0x11, 0x10, 0x13, 0x18, 0x28,
  39. 0x1a, 0x18, 0x16, 0x16, 0x18, 0x31, 0x23, 0x25,
  40. 0x1d, 0x28, 0x3a, 0x33, 0x3d, 0x3c, 0x39, 0x33,
  41. 0x38, 0x37, 0x40, 0x48, 0x5c, 0x4e, 0x40, 0x44,
  42. 0x57, 0x45, 0x37, 0x38, 0x50, 0x6d, 0x51, 0x57,
  43. 0x5f, 0x62, 0x67, 0x68, 0x67, 0x3e, 0x4d, 0x71,
  44. 0x79, 0x70, 0x64, 0x78, 0x5c, 0x65, 0x67, 0x63,
  45. 1,
  46. #define JPEG_QT1_OFFSET 72
  47. 0x11, 0x12, 0x12, 0x18, 0x15, 0x18, 0x2f, 0x1a,
  48. 0x1a, 0x2f, 0x63, 0x42, 0x38, 0x42, 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. 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
  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. 0xff, 0xda, 0x00, 0x0c, /* SOS (start of scan) */
  125. 0x03, 0x01, 0x00, 0x02, 0x11, 0x03, 0x11, 0x00, 0x3f, 0x00
  126. #define JPEG_HDR_SZ 589
  127. #endif
  128. };
  129. /* define the JPEG header */
  130. static void jpeg_define(u8 *jpeg_hdr,
  131. int height,
  132. int width,
  133. int samplesY)
  134. {
  135. memcpy(jpeg_hdr, jpeg_head, sizeof jpeg_head);
  136. #ifndef CONEX_CAM
  137. jpeg_hdr[JPEG_HEIGHT_OFFSET + 0] = height >> 8;
  138. jpeg_hdr[JPEG_HEIGHT_OFFSET + 1] = height;
  139. jpeg_hdr[JPEG_HEIGHT_OFFSET + 2] = width >> 8;
  140. jpeg_hdr[JPEG_HEIGHT_OFFSET + 3] = width;
  141. jpeg_hdr[JPEG_HEIGHT_OFFSET + 6] = samplesY;
  142. #endif
  143. }
  144. /* set the JPEG quality */
  145. static void jpeg_set_qual(u8 *jpeg_hdr,
  146. int quality)
  147. {
  148. int i, sc;
  149. if (quality <= 0)
  150. sc = 5000;
  151. else if (quality < 50)
  152. sc = 5000 / quality;
  153. else
  154. sc = 200 - quality * 2;
  155. for (i = 0; i < 64; i++) {
  156. jpeg_hdr[JPEG_QT0_OFFSET + i] =
  157. (jpeg_head[JPEG_QT0_OFFSET + i] * sc + 50) / 100;
  158. jpeg_hdr[JPEG_QT1_OFFSET + i] =
  159. (jpeg_head[JPEG_QT1_OFFSET + i] * sc + 50) / 100;
  160. }
  161. }
  162. #endif