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1 /* |
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2 * jcmarker.c |
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3 * |
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4 * Copyright (C) 1991-1998, Thomas G. Lane. |
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5 * This file is part of the Independent JPEG Group's software. |
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6 * For conditions of distribution and use, see the accompanying README file. |
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7 * |
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8 * This file contains routines to write JPEG datastream markers. |
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9 */ |
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10 |
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11 #define JPEG_INTERNALS |
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12 #include "jinclude.h" |
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13 #include "jpeglib.h" |
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14 |
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15 |
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16 typedef enum { /* JPEG marker codes */ |
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17 M_SOF0 = 0xc0, |
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18 M_SOF1 = 0xc1, |
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19 M_SOF2 = 0xc2, |
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20 M_SOF3 = 0xc3, |
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21 |
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22 M_SOF5 = 0xc5, |
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23 M_SOF6 = 0xc6, |
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24 M_SOF7 = 0xc7, |
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25 |
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26 M_JPG = 0xc8, |
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27 M_SOF9 = 0xc9, |
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28 M_SOF10 = 0xca, |
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29 M_SOF11 = 0xcb, |
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30 |
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31 M_SOF13 = 0xcd, |
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32 M_SOF14 = 0xce, |
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33 M_SOF15 = 0xcf, |
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34 |
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35 M_DHT = 0xc4, |
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36 |
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37 M_DAC = 0xcc, |
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38 |
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39 M_RST0 = 0xd0, |
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40 M_RST1 = 0xd1, |
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41 M_RST2 = 0xd2, |
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42 M_RST3 = 0xd3, |
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43 M_RST4 = 0xd4, |
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44 M_RST5 = 0xd5, |
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45 M_RST6 = 0xd6, |
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46 M_RST7 = 0xd7, |
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47 |
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48 M_SOI = 0xd8, |
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49 M_EOI = 0xd9, |
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50 M_SOS = 0xda, |
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51 M_DQT = 0xdb, |
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52 M_DNL = 0xdc, |
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53 M_DRI = 0xdd, |
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54 M_DHP = 0xde, |
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55 M_EXP = 0xdf, |
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56 |
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57 M_APP0 = 0xe0, |
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58 M_APP1 = 0xe1, |
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59 M_APP2 = 0xe2, |
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60 M_APP3 = 0xe3, |
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61 M_APP4 = 0xe4, |
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62 M_APP5 = 0xe5, |
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63 M_APP6 = 0xe6, |
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64 M_APP7 = 0xe7, |
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65 M_APP8 = 0xe8, |
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66 M_APP9 = 0xe9, |
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67 M_APP10 = 0xea, |
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68 M_APP11 = 0xeb, |
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69 M_APP12 = 0xec, |
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70 M_APP13 = 0xed, |
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71 M_APP14 = 0xee, |
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72 M_APP15 = 0xef, |
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73 |
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74 M_JPG0 = 0xf0, |
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75 M_JPG13 = 0xfd, |
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76 M_COM = 0xfe, |
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77 |
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78 M_TEM = 0x01, |
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79 |
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80 M_ERROR = 0x100 |
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81 } JPEG_MARKER; |
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82 |
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83 |
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84 /* Private state */ |
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85 |
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86 typedef struct { |
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87 struct jpeg_marker_writer pub; /* public fields */ |
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88 |
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89 unsigned int last_restart_interval; /* last DRI value emitted; 0 after SOI */ |
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90 } my_marker_writer; |
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91 |
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92 typedef my_marker_writer * my_marker_ptr; |
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93 |
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94 |
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95 /* |
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96 * Basic output routines. |
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97 * |
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98 * Note that we do not support suspension while writing a marker. |
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99 * Therefore, an application using suspension must ensure that there is |
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100 * enough buffer space for the initial markers (typ. 600-700 bytes) before |
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101 * calling jpeg_start_compress, and enough space to write the trailing EOI |
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102 * (a few bytes) before calling jpeg_finish_compress. Multipass compression |
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103 * modes are not supported at all with suspension, so those two are the only |
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104 * points where markers will be written. |
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105 */ |
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106 |
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107 LOCAL(void) |
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108 emit_byte (j_compress_ptr cinfo, int val) |
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109 /* Emit a byte */ |
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110 { |
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111 struct jpeg_destination_mgr * dest = cinfo->dest; |
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112 |
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113 *(dest->next_output_byte)++ = (JOCTET) val; |
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114 if (--dest->free_in_buffer == 0) { |
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115 if (! (*dest->empty_output_buffer) (cinfo)) |
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116 ERREXIT(cinfo, JERR_CANT_SUSPEND); |
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117 } |
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118 } |
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119 |
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120 |
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121 LOCAL(void) |
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122 emit_marker (j_compress_ptr cinfo, JPEG_MARKER mark) |
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123 /* Emit a marker code */ |
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124 { |
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125 emit_byte(cinfo, 0xFF); |
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126 emit_byte(cinfo, (int) mark); |
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127 } |
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128 |
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129 |
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130 LOCAL(void) |
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131 emit_2bytes (j_compress_ptr cinfo, int value) |
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132 /* Emit a 2-byte integer; these are always MSB first in JPEG files */ |
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133 { |
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134 emit_byte(cinfo, (value >> 8) & 0xFF); |
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135 emit_byte(cinfo, value & 0xFF); |
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136 } |
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137 |
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138 |
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139 /* |
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140 * Routines to write specific marker types. |
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141 */ |
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142 |
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143 LOCAL(int) |
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144 emit_dqt (j_compress_ptr cinfo, int index) |
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145 /* Emit a DQT marker */ |
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146 /* Returns the precision used (0 = 8bits, 1 = 16bits) for baseline checking */ |
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147 { |
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148 JQUANT_TBL * qtbl = cinfo->quant_tbl_ptrs[index]; |
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149 int prec; |
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150 int i; |
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151 |
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152 if (qtbl == NULL) |
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153 ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, index); |
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154 |
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155 prec = 0; |
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156 for (i = 0; i < DCTSIZE2; i++) { |
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157 if (qtbl->quantval[i] > 255) |
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158 prec = 1; |
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159 } |
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160 |
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161 if (! qtbl->sent_table) { |
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162 emit_marker(cinfo, M_DQT); |
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163 |
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164 emit_2bytes(cinfo, prec ? DCTSIZE2*2 + 1 + 2 : DCTSIZE2 + 1 + 2); |
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165 |
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166 emit_byte(cinfo, index + (prec<<4)); |
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167 |
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168 for (i = 0; i < DCTSIZE2; i++) { |
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169 /* The table entries must be emitted in zigzag order. */ |
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170 unsigned int qval = qtbl->quantval[jpeg_natural_order[i]]; |
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171 if (prec) |
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172 emit_byte(cinfo, (int) (qval >> 8)); |
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173 emit_byte(cinfo, (int) (qval & 0xFF)); |
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174 } |
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175 |
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176 qtbl->sent_table = TRUE; |
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177 } |
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178 |
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179 return prec; |
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180 } |
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181 |
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182 |
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183 LOCAL(void) |
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184 emit_dht (j_compress_ptr cinfo, int index, boolean is_ac) |
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185 /* Emit a DHT marker */ |
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186 { |
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187 JHUFF_TBL * htbl; |
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188 int length, i; |
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189 |
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190 if (is_ac) { |
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191 htbl = cinfo->ac_huff_tbl_ptrs[index]; |
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192 index += 0x10; /* output index has AC bit set */ |
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193 } else { |
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194 htbl = cinfo->dc_huff_tbl_ptrs[index]; |
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195 } |
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196 |
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197 if (htbl == NULL) |
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198 ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, index); |
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199 |
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200 if (! htbl->sent_table) { |
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201 emit_marker(cinfo, M_DHT); |
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202 |
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203 length = 0; |
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204 for (i = 1; i <= 16; i++) |
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205 length += htbl->bits[i]; |
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206 |
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207 emit_2bytes(cinfo, length + 2 + 1 + 16); |
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208 emit_byte(cinfo, index); |
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209 |
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210 for (i = 1; i <= 16; i++) |
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211 emit_byte(cinfo, htbl->bits[i]); |
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212 |
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213 for (i = 0; i < length; i++) |
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214 emit_byte(cinfo, htbl->huffval[i]); |
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215 |
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216 htbl->sent_table = TRUE; |
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217 } |
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218 } |
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219 |
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220 |
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221 LOCAL(void) |
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222 emit_dac (j_compress_ptr cinfo) |
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223 /* Emit a DAC marker */ |
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224 /* Since the useful info is so small, we want to emit all the tables in */ |
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225 /* one DAC marker. Therefore this routine does its own scan of the table. */ |
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226 { |
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227 #ifdef C_ARITH_CODING_SUPPORTED |
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228 char dc_in_use[NUM_ARITH_TBLS]; |
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229 char ac_in_use[NUM_ARITH_TBLS]; |
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230 int length, i; |
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231 jpeg_component_info *compptr; |
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232 |
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233 for (i = 0; i < NUM_ARITH_TBLS; i++) |
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234 dc_in_use[i] = ac_in_use[i] = 0; |
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235 |
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236 for (i = 0; i < cinfo->comps_in_scan; i++) { |
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237 compptr = cinfo->cur_comp_info[i]; |
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238 dc_in_use[compptr->dc_tbl_no] = 1; |
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239 ac_in_use[compptr->ac_tbl_no] = 1; |
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240 } |
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241 |
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242 length = 0; |
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243 for (i = 0; i < NUM_ARITH_TBLS; i++) |
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244 length += dc_in_use[i] + ac_in_use[i]; |
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245 |
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246 emit_marker(cinfo, M_DAC); |
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247 |
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248 emit_2bytes(cinfo, length*2 + 2); |
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249 |
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250 for (i = 0; i < NUM_ARITH_TBLS; i++) { |
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251 if (dc_in_use[i]) { |
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252 emit_byte(cinfo, i); |
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253 emit_byte(cinfo, cinfo->arith_dc_L[i] + (cinfo->arith_dc_U[i]<<4)); |
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254 } |
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255 if (ac_in_use[i]) { |
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256 emit_byte(cinfo, i + 0x10); |
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257 emit_byte(cinfo, cinfo->arith_ac_K[i]); |
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258 } |
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259 } |
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260 #endif /* C_ARITH_CODING_SUPPORTED */ |
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261 } |
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262 |
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263 |
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264 LOCAL(void) |
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265 emit_dri (j_compress_ptr cinfo) |
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266 /* Emit a DRI marker */ |
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267 { |
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268 emit_marker(cinfo, M_DRI); |
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269 |
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270 emit_2bytes(cinfo, 4); /* fixed length */ |
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271 |
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272 emit_2bytes(cinfo, (int) cinfo->restart_interval); |
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273 } |
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274 |
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275 |
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276 LOCAL(void) |
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277 emit_sof (j_compress_ptr cinfo, JPEG_MARKER code) |
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278 /* Emit a SOF marker */ |
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279 { |
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280 int ci; |
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281 jpeg_component_info *compptr; |
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282 |
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283 emit_marker(cinfo, code); |
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284 |
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285 emit_2bytes(cinfo, 3 * cinfo->num_components + 2 + 5 + 1); /* length */ |
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286 |
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287 /* Make sure image isn't bigger than SOF field can handle */ |
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288 if ((long) cinfo->image_height > 65535L || |
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289 (long) cinfo->image_width > 65535L) |
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290 ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) 65535); |
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291 |
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292 emit_byte(cinfo, cinfo->data_precision); |
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293 emit_2bytes(cinfo, (int) cinfo->image_height); |
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294 emit_2bytes(cinfo, (int) cinfo->image_width); |
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295 |
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296 emit_byte(cinfo, cinfo->num_components); |
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297 |
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298 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; |
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299 ci++, compptr++) { |
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300 emit_byte(cinfo, compptr->component_id); |
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301 emit_byte(cinfo, (compptr->h_samp_factor << 4) + compptr->v_samp_factor); |
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302 emit_byte(cinfo, compptr->quant_tbl_no); |
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303 } |
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304 } |
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305 |
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306 |
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307 LOCAL(void) |
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308 emit_sos (j_compress_ptr cinfo) |
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309 /* Emit a SOS marker */ |
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310 { |
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311 int i, td, ta; |
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312 jpeg_component_info *compptr; |
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313 |
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314 emit_marker(cinfo, M_SOS); |
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315 |
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316 emit_2bytes(cinfo, 2 * cinfo->comps_in_scan + 2 + 1 + 3); /* length */ |
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317 |
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318 emit_byte(cinfo, cinfo->comps_in_scan); |
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319 |
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320 for (i = 0; i < cinfo->comps_in_scan; i++) { |
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321 compptr = cinfo->cur_comp_info[i]; |
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322 emit_byte(cinfo, compptr->component_id); |
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323 td = compptr->dc_tbl_no; |
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324 ta = compptr->ac_tbl_no; |
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325 if (cinfo->progressive_mode) { |
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326 /* Progressive mode: only DC or only AC tables are used in one scan; |
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327 * furthermore, Huffman coding of DC refinement uses no table at all. |
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328 * We emit 0 for unused field(s); this is recommended by the P&M text |
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329 * but does not seem to be specified in the standard. |
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330 */ |
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331 if (cinfo->Ss == 0) { |
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332 ta = 0; /* DC scan */ |
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333 if (cinfo->Ah != 0 && !cinfo->arith_code) |
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334 td = 0; /* no DC table either */ |
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335 } else { |
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336 td = 0; /* AC scan */ |
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337 } |
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338 } |
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339 emit_byte(cinfo, (td << 4) + ta); |
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340 } |
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341 |
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342 emit_byte(cinfo, cinfo->Ss); |
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343 emit_byte(cinfo, cinfo->Se); |
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344 emit_byte(cinfo, (cinfo->Ah << 4) + cinfo->Al); |
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345 } |
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346 |
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347 |
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348 LOCAL(void) |
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349 emit_jfif_app0 (j_compress_ptr cinfo) |
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350 /* Emit a JFIF-compliant APP0 marker */ |
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351 { |
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352 /* |
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353 * Length of APP0 block (2 bytes) |
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354 * Block ID (4 bytes - ASCII "JFIF") |
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355 * Zero byte (1 byte to terminate the ID string) |
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356 * Version Major, Minor (2 bytes - major first) |
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357 * Units (1 byte - 0x00 = none, 0x01 = inch, 0x02 = cm) |
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358 * Xdpu (2 bytes - dots per unit horizontal) |
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359 * Ydpu (2 bytes - dots per unit vertical) |
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360 * Thumbnail X size (1 byte) |
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361 * Thumbnail Y size (1 byte) |
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362 */ |
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363 |
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364 emit_marker(cinfo, M_APP0); |
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365 |
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366 emit_2bytes(cinfo, 2 + 4 + 1 + 2 + 1 + 2 + 2 + 1 + 1); /* length */ |
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367 |
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368 emit_byte(cinfo, 0x4A); /* Identifier: ASCII "JFIF" */ |
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369 emit_byte(cinfo, 0x46); |
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370 emit_byte(cinfo, 0x49); |
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371 emit_byte(cinfo, 0x46); |
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372 emit_byte(cinfo, 0); |
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373 emit_byte(cinfo, cinfo->JFIF_major_version); /* Version fields */ |
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374 emit_byte(cinfo, cinfo->JFIF_minor_version); |
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375 emit_byte(cinfo, cinfo->density_unit); /* Pixel size information */ |
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376 emit_2bytes(cinfo, (int) cinfo->X_density); |
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377 emit_2bytes(cinfo, (int) cinfo->Y_density); |
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378 emit_byte(cinfo, 0); /* No thumbnail image */ |
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379 emit_byte(cinfo, 0); |
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380 } |
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381 |
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382 |
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383 LOCAL(void) |
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384 emit_adobe_app14 (j_compress_ptr cinfo) |
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385 /* Emit an Adobe APP14 marker */ |
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386 { |
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387 /* |
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388 * Length of APP14 block (2 bytes) |
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389 * Block ID (5 bytes - ASCII "Adobe") |
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390 * Version Number (2 bytes - currently 100) |
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391 * Flags0 (2 bytes - currently 0) |
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392 * Flags1 (2 bytes - currently 0) |
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393 * Color transform (1 byte) |
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394 * |
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395 * Although Adobe TN 5116 mentions Version = 101, all the Adobe files |
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396 * now in circulation seem to use Version = 100, so that's what we write. |
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397 * |
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398 * We write the color transform byte as 1 if the JPEG color space is |
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399 * YCbCr, 2 if it's YCCK, 0 otherwise. Adobe's definition has to do with |
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400 * whether the encoder performed a transformation, which is pretty useless. |
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401 */ |
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402 |
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403 emit_marker(cinfo, M_APP14); |
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404 |
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405 emit_2bytes(cinfo, 2 + 5 + 2 + 2 + 2 + 1); /* length */ |
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406 |
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407 emit_byte(cinfo, 0x41); /* Identifier: ASCII "Adobe" */ |
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408 emit_byte(cinfo, 0x64); |
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409 emit_byte(cinfo, 0x6F); |
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410 emit_byte(cinfo, 0x62); |
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411 emit_byte(cinfo, 0x65); |
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412 emit_2bytes(cinfo, 100); /* Version */ |
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413 emit_2bytes(cinfo, 0); /* Flags0 */ |
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414 emit_2bytes(cinfo, 0); /* Flags1 */ |
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415 switch (cinfo->jpeg_color_space) { |
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416 case JCS_YCbCr: |
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417 emit_byte(cinfo, 1); /* Color transform = 1 */ |
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418 break; |
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419 case JCS_YCCK: |
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420 emit_byte(cinfo, 2); /* Color transform = 2 */ |
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421 break; |
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422 default: |
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423 emit_byte(cinfo, 0); /* Color transform = 0 */ |
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424 break; |
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425 } |
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426 } |
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427 |
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428 |
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429 /* |
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430 * These routines allow writing an arbitrary marker with parameters. |
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431 * The only intended use is to emit COM or APPn markers after calling |
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432 * write_file_header and before calling write_frame_header. |
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433 * Other uses are not guaranteed to produce desirable results. |
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434 * Counting the parameter bytes properly is the caller's responsibility. |
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435 */ |
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436 |
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437 METHODDEF(void) |
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438 write_marker_header (j_compress_ptr cinfo, int marker, unsigned int datalen) |
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439 /* Emit an arbitrary marker header */ |
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440 { |
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441 if (datalen > (unsigned int) 65533) /* safety check */ |
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442 ERREXIT(cinfo, JERR_BAD_LENGTH); |
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443 |
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444 emit_marker(cinfo, (JPEG_MARKER) marker); |
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445 |
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446 emit_2bytes(cinfo, (int) (datalen + 2)); /* total length */ |
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447 } |
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448 |
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449 METHODDEF(void) |
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450 write_marker_byte (j_compress_ptr cinfo, int val) |
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451 /* Emit one byte of marker parameters following write_marker_header */ |
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452 { |
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453 emit_byte(cinfo, val); |
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454 } |
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455 |
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456 |
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457 /* |
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458 * Write datastream header. |
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459 * This consists of an SOI and optional APPn markers. |
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460 * We recommend use of the JFIF marker, but not the Adobe marker, |
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461 * when using YCbCr or grayscale data. The JFIF marker should NOT |
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462 * be used for any other JPEG colorspace. The Adobe marker is helpful |
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463 * to distinguish RGB, CMYK, and YCCK colorspaces. |
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464 * Note that an application can write additional header markers after |
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465 * jpeg_start_compress returns. |
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466 */ |
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467 |
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468 METHODDEF(void) |
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469 write_file_header (j_compress_ptr cinfo) |
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470 { |
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471 my_marker_ptr marker = (my_marker_ptr) cinfo->marker; |
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472 |
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473 emit_marker(cinfo, M_SOI); /* first the SOI */ |
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474 |
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475 /* SOI is defined to reset restart interval to 0 */ |
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476 marker->last_restart_interval = 0; |
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477 |
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478 if (cinfo->write_JFIF_header) /* next an optional JFIF APP0 */ |
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479 emit_jfif_app0(cinfo); |
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480 if (cinfo->write_Adobe_marker) /* next an optional Adobe APP14 */ |
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481 emit_adobe_app14(cinfo); |
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482 } |
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483 |
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484 |
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485 /* |
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486 * Write frame header. |
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487 * This consists of DQT and SOFn markers. |
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488 * Note that we do not emit the SOF until we have emitted the DQT(s). |
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489 * This avoids compatibility problems with incorrect implementations that |
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490 * try to error-check the quant table numbers as soon as they see the SOF. |
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491 */ |
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492 |
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493 METHODDEF(void) |
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494 write_frame_header (j_compress_ptr cinfo) |
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495 { |
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496 int ci, prec; |
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497 boolean is_baseline; |
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498 jpeg_component_info *compptr; |
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499 |
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500 /* Emit DQT for each quantization table. |
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501 * Note that emit_dqt() suppresses any duplicate tables. |
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502 */ |
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503 prec = 0; |
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504 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; |
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505 ci++, compptr++) { |
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506 prec += emit_dqt(cinfo, compptr->quant_tbl_no); |
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507 } |
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508 /* now prec is nonzero iff there are any 16-bit quant tables. */ |
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509 |
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510 /* Check for a non-baseline specification. |
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511 * Note we assume that Huffman table numbers won't be changed later. |
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512 */ |
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513 if (cinfo->arith_code || cinfo->progressive_mode || |
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514 cinfo->data_precision != 8) { |
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515 is_baseline = FALSE; |
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516 } else { |
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517 is_baseline = TRUE; |
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518 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; |
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519 ci++, compptr++) { |
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520 if (compptr->dc_tbl_no > 1 || compptr->ac_tbl_no > 1) |
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521 is_baseline = FALSE; |
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522 } |
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523 if (prec && is_baseline) { |
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524 is_baseline = FALSE; |
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525 /* If it's baseline except for quantizer size, warn the user */ |
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526 TRACEMS(cinfo, 0, JTRC_16BIT_TABLES); |
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527 } |
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528 } |
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529 |
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530 /* Emit the proper SOF marker */ |
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531 if (cinfo->arith_code) { |
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532 emit_sof(cinfo, M_SOF9); /* SOF code for arithmetic coding */ |
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533 } else { |
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534 if (cinfo->progressive_mode) |
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535 emit_sof(cinfo, M_SOF2); /* SOF code for progressive Huffman */ |
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536 else if (is_baseline) |
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537 emit_sof(cinfo, M_SOF0); /* SOF code for baseline implementation */ |
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538 else |
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539 emit_sof(cinfo, M_SOF1); /* SOF code for non-baseline Huffman file */ |
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540 } |
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541 } |
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542 |
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543 |
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544 /* |
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545 * Write scan header. |
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546 * This consists of DHT or DAC markers, optional DRI, and SOS. |
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547 * Compressed data will be written following the SOS. |
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548 */ |
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549 |
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550 METHODDEF(void) |
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551 write_scan_header (j_compress_ptr cinfo) |
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552 { |
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553 my_marker_ptr marker = (my_marker_ptr) cinfo->marker; |
|
554 int i; |
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555 jpeg_component_info *compptr; |
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556 |
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557 if (cinfo->arith_code) { |
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558 /* Emit arith conditioning info. We may have some duplication |
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559 * if the file has multiple scans, but it's so small it's hardly |
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560 * worth worrying about. |
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561 */ |
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562 emit_dac(cinfo); |
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563 } else { |
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564 /* Emit Huffman tables. |
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565 * Note that emit_dht() suppresses any duplicate tables. |
|
566 */ |
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567 for (i = 0; i < cinfo->comps_in_scan; i++) { |
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568 compptr = cinfo->cur_comp_info[i]; |
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569 if (cinfo->progressive_mode) { |
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570 /* Progressive mode: only DC or only AC tables are used in one scan */ |
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571 if (cinfo->Ss == 0) { |
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572 if (cinfo->Ah == 0) /* DC needs no table for refinement scan */ |
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573 emit_dht(cinfo, compptr->dc_tbl_no, FALSE); |
|
574 } else { |
|
575 emit_dht(cinfo, compptr->ac_tbl_no, TRUE); |
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576 } |
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577 } else { |
|
578 /* Sequential mode: need both DC and AC tables */ |
|
579 emit_dht(cinfo, compptr->dc_tbl_no, FALSE); |
|
580 emit_dht(cinfo, compptr->ac_tbl_no, TRUE); |
|
581 } |
|
582 } |
|
583 } |
|
584 |
|
585 /* Emit DRI if required --- note that DRI value could change for each scan. |
|
586 * We avoid wasting space with unnecessary DRIs, however. |
|
587 */ |
|
588 if (cinfo->restart_interval != marker->last_restart_interval) { |
|
589 emit_dri(cinfo); |
|
590 marker->last_restart_interval = cinfo->restart_interval; |
|
591 } |
|
592 |
|
593 emit_sos(cinfo); |
|
594 } |
|
595 |
|
596 |
|
597 /* |
|
598 * Write datastream trailer. |
|
599 */ |
|
600 |
|
601 METHODDEF(void) |
|
602 write_file_trailer (j_compress_ptr cinfo) |
|
603 { |
|
604 emit_marker(cinfo, M_EOI); |
|
605 } |
|
606 |
|
607 |
|
608 /* |
|
609 * Write an abbreviated table-specification datastream. |
|
610 * This consists of SOI, DQT and DHT tables, and EOI. |
|
611 * Any table that is defined and not marked sent_table = TRUE will be |
|
612 * emitted. Note that all tables will be marked sent_table = TRUE at exit. |
|
613 */ |
|
614 |
|
615 METHODDEF(void) |
|
616 write_tables_only (j_compress_ptr cinfo) |
|
617 { |
|
618 int i; |
|
619 |
|
620 emit_marker(cinfo, M_SOI); |
|
621 |
|
622 for (i = 0; i < NUM_QUANT_TBLS; i++) { |
|
623 if (cinfo->quant_tbl_ptrs[i] != NULL) |
|
624 (void) emit_dqt(cinfo, i); |
|
625 } |
|
626 |
|
627 if (! cinfo->arith_code) { |
|
628 for (i = 0; i < NUM_HUFF_TBLS; i++) { |
|
629 if (cinfo->dc_huff_tbl_ptrs[i] != NULL) |
|
630 emit_dht(cinfo, i, FALSE); |
|
631 if (cinfo->ac_huff_tbl_ptrs[i] != NULL) |
|
632 emit_dht(cinfo, i, TRUE); |
|
633 } |
|
634 } |
|
635 |
|
636 emit_marker(cinfo, M_EOI); |
|
637 } |
|
638 |
|
639 |
|
640 /* |
|
641 * Initialize the marker writer module. |
|
642 */ |
|
643 |
|
644 GLOBAL(void) |
|
645 jinit_marker_writer (j_compress_ptr cinfo) |
|
646 { |
|
647 my_marker_ptr marker; |
|
648 |
|
649 /* Create the subobject */ |
|
650 marker = (my_marker_ptr) |
|
651 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, |
|
652 SIZEOF(my_marker_writer)); |
|
653 cinfo->marker = (struct jpeg_marker_writer *) marker; |
|
654 /* Initialize method pointers */ |
|
655 marker->pub.write_file_header = write_file_header; |
|
656 marker->pub.write_frame_header = write_frame_header; |
|
657 marker->pub.write_scan_header = write_scan_header; |
|
658 marker->pub.write_file_trailer = write_file_trailer; |
|
659 marker->pub.write_tables_only = write_tables_only; |
|
660 marker->pub.write_marker_header = write_marker_header; |
|
661 marker->pub.write_marker_byte = write_marker_byte; |
|
662 /* Initialize private state */ |
|
663 marker->last_restart_interval = 0; |
|
664 } |