1 | /* |
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2 | * jdmarker.c |
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3 | * |
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4 | * Copyright (C) 1991-1998, Thomas G. Lane. |
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5 | * Modified 2009 by Guido Vollbeding. |
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6 | * This file is part of the Independent JPEG Group's software. |
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7 | * For conditions of distribution and use, see the accompanying README file. |
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8 | * |
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9 | * This file contains routines to decode JPEG datastream markers. |
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10 | * Most of the complexity arises from our desire to support input |
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11 | * suspension: if not all of the data for a marker is available, |
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12 | * we must exit back to the application. On resumption, we reprocess |
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13 | * the marker. |
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14 | */ |
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15 | |
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16 | #define JPEG_INTERNALS |
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17 | #include "jinclude.h" |
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18 | #include "jpeglib.h" |
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19 | |
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20 | |
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21 | typedef enum { /* JPEG marker codes */ |
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22 | M_SOF0 = 0xc0, |
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23 | M_SOF1 = 0xc1, |
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24 | M_SOF2 = 0xc2, |
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25 | M_SOF3 = 0xc3, |
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26 | |
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27 | M_SOF5 = 0xc5, |
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28 | M_SOF6 = 0xc6, |
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29 | M_SOF7 = 0xc7, |
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30 | |
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31 | M_JPG = 0xc8, |
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32 | M_SOF9 = 0xc9, |
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33 | M_SOF10 = 0xca, |
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34 | M_SOF11 = 0xcb, |
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35 | |
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36 | M_SOF13 = 0xcd, |
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37 | M_SOF14 = 0xce, |
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38 | M_SOF15 = 0xcf, |
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39 | |
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40 | M_DHT = 0xc4, |
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41 | |
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42 | M_DAC = 0xcc, |
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43 | |
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44 | M_RST0 = 0xd0, |
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45 | M_RST1 = 0xd1, |
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46 | M_RST2 = 0xd2, |
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47 | M_RST3 = 0xd3, |
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48 | M_RST4 = 0xd4, |
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49 | M_RST5 = 0xd5, |
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50 | M_RST6 = 0xd6, |
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51 | M_RST7 = 0xd7, |
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52 | |
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53 | M_SOI = 0xd8, |
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54 | M_EOI = 0xd9, |
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55 | M_SOS = 0xda, |
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56 | M_DQT = 0xdb, |
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57 | M_DNL = 0xdc, |
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58 | M_DRI = 0xdd, |
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59 | M_DHP = 0xde, |
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60 | M_EXP = 0xdf, |
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61 | |
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62 | M_APP0 = 0xe0, |
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63 | M_APP1 = 0xe1, |
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64 | M_APP2 = 0xe2, |
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65 | M_APP3 = 0xe3, |
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66 | M_APP4 = 0xe4, |
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67 | M_APP5 = 0xe5, |
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68 | M_APP6 = 0xe6, |
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69 | M_APP7 = 0xe7, |
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70 | M_APP8 = 0xe8, |
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71 | M_APP9 = 0xe9, |
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72 | M_APP10 = 0xea, |
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73 | M_APP11 = 0xeb, |
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74 | M_APP12 = 0xec, |
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75 | M_APP13 = 0xed, |
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76 | M_APP14 = 0xee, |
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77 | M_APP15 = 0xef, |
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78 | |
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79 | M_JPG0 = 0xf0, |
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80 | M_JPG13 = 0xfd, |
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81 | M_COM = 0xfe, |
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82 | |
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83 | M_TEM = 0x01, |
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84 | |
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85 | M_ERROR = 0x100 |
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86 | } JPEG_MARKER; |
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87 | |
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88 | |
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89 | /* Private state */ |
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90 | |
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91 | typedef struct { |
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92 | struct jpeg_marker_reader pub; /* public fields */ |
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93 | |
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94 | /* Application-overridable marker processing methods */ |
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95 | jpeg_marker_parser_method process_COM; |
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96 | jpeg_marker_parser_method process_APPn[16]; |
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97 | |
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98 | /* Limit on marker data length to save for each marker type */ |
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99 | unsigned int length_limit_COM; |
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100 | unsigned int length_limit_APPn[16]; |
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101 | |
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102 | /* Status of COM/APPn marker saving */ |
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103 | jpeg_saved_marker_ptr cur_marker; /* NULL if not processing a marker */ |
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104 | unsigned int bytes_read; /* data bytes read so far in marker */ |
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105 | /* Note: cur_marker is not linked into marker_list until it's all read. */ |
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106 | } my_marker_reader; |
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107 | |
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108 | typedef my_marker_reader * my_marker_ptr; |
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109 | |
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110 | |
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111 | /* |
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112 | * Macros for fetching data from the data source module. |
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113 | * |
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114 | * At all times, cinfo->src->next_input_byte and ->bytes_in_buffer reflect |
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115 | * the current restart point; we update them only when we have reached a |
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116 | * suitable place to restart if a suspension occurs. |
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117 | */ |
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118 | |
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119 | /* Declare and initialize local copies of input pointer/count */ |
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120 | #define INPUT_VARS(cinfo) \ |
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121 | struct jpeg_source_mgr * datasrc = (cinfo)->src; \ |
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122 | const JOCTET * next_input_byte = datasrc->next_input_byte; \ |
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123 | size_t bytes_in_buffer = datasrc->bytes_in_buffer |
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124 | |
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125 | /* Unload the local copies --- do this only at a restart boundary */ |
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126 | #define INPUT_SYNC(cinfo) \ |
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127 | ( datasrc->next_input_byte = next_input_byte, \ |
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128 | datasrc->bytes_in_buffer = bytes_in_buffer ) |
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129 | |
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130 | /* Reload the local copies --- used only in MAKE_BYTE_AVAIL */ |
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131 | #define INPUT_RELOAD(cinfo) \ |
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132 | ( next_input_byte = datasrc->next_input_byte, \ |
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133 | bytes_in_buffer = datasrc->bytes_in_buffer ) |
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134 | |
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135 | /* Internal macro for INPUT_BYTE and INPUT_2BYTES: make a byte available. |
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136 | * Note we do *not* do INPUT_SYNC before calling fill_input_buffer, |
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137 | * but we must reload the local copies after a successful fill. |
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138 | */ |
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139 | #define MAKE_BYTE_AVAIL(cinfo,action) \ |
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140 | if (bytes_in_buffer == 0) { \ |
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141 | if (! (*datasrc->fill_input_buffer) (cinfo)) \ |
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142 | { action; } \ |
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143 | INPUT_RELOAD(cinfo); \ |
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144 | } |
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145 | |
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146 | /* Read a byte into variable V. |
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147 | * If must suspend, take the specified action (typically "return FALSE"). |
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148 | */ |
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149 | #define INPUT_BYTE(cinfo,V,action) \ |
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150 | MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \ |
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151 | bytes_in_buffer--; \ |
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152 | V = GETJOCTET(*next_input_byte++); ) |
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153 | |
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154 | /* As above, but read two bytes interpreted as an unsigned 16-bit integer. |
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155 | * V should be declared unsigned int or perhaps INT32. |
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156 | */ |
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157 | #define INPUT_2BYTES(cinfo,V,action) \ |
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158 | MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \ |
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159 | bytes_in_buffer--; \ |
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160 | V = ((unsigned int) GETJOCTET(*next_input_byte++)) << 8; \ |
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161 | MAKE_BYTE_AVAIL(cinfo,action); \ |
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162 | bytes_in_buffer--; \ |
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163 | V += GETJOCTET(*next_input_byte++); ) |
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164 | |
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165 | |
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166 | /* |
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167 | * Routines to process JPEG markers. |
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168 | * |
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169 | * Entry condition: JPEG marker itself has been read and its code saved |
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170 | * in cinfo->unread_marker; input restart point is just after the marker. |
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171 | * |
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172 | * Exit: if return TRUE, have read and processed any parameters, and have |
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173 | * updated the restart point to point after the parameters. |
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174 | * If return FALSE, was forced to suspend before reaching end of |
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175 | * marker parameters; restart point has not been moved. Same routine |
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176 | * will be called again after application supplies more input data. |
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177 | * |
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178 | * This approach to suspension assumes that all of a marker's parameters |
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179 | * can fit into a single input bufferload. This should hold for "normal" |
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180 | * markers. Some COM/APPn markers might have large parameter segments |
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181 | * that might not fit. If we are simply dropping such a marker, we use |
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182 | * skip_input_data to get past it, and thereby put the problem on the |
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183 | * source manager's shoulders. If we are saving the marker's contents |
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184 | * into memory, we use a slightly different convention: when forced to |
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185 | * suspend, the marker processor updates the restart point to the end of |
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186 | * what it's consumed (ie, the end of the buffer) before returning FALSE. |
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187 | * On resumption, cinfo->unread_marker still contains the marker code, |
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188 | * but the data source will point to the next chunk of marker data. |
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189 | * The marker processor must retain internal state to deal with this. |
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190 | * |
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191 | * Note that we don't bother to avoid duplicate trace messages if a |
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192 | * suspension occurs within marker parameters. Other side effects |
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193 | * require more care. |
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194 | */ |
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195 | |
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196 | |
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197 | LOCAL(boolean) |
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198 | get_soi (j_decompress_ptr cinfo) |
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199 | /* Process an SOI marker */ |
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200 | { |
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201 | int i; |
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202 | |
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203 | TRACEMS(cinfo, 1, JTRC_SOI); |
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204 | |
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205 | if (cinfo->marker->saw_SOI) |
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206 | ERREXIT(cinfo, JERR_SOI_DUPLICATE); |
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207 | |
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208 | /* Reset all parameters that are defined to be reset by SOI */ |
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209 | |
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210 | for (i = 0; i < NUM_ARITH_TBLS; i++) { |
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211 | cinfo->arith_dc_L[i] = 0; |
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212 | cinfo->arith_dc_U[i] = 1; |
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213 | cinfo->arith_ac_K[i] = 5; |
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214 | } |
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215 | cinfo->restart_interval = 0; |
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216 | |
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217 | /* Set initial assumptions for colorspace etc */ |
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218 | |
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219 | cinfo->jpeg_color_space = JCS_UNKNOWN; |
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220 | cinfo->CCIR601_sampling = FALSE; /* Assume non-CCIR sampling??? */ |
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221 | |
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222 | cinfo->saw_JFIF_marker = FALSE; |
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223 | cinfo->JFIF_major_version = 1; /* set default JFIF APP0 values */ |
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224 | cinfo->JFIF_minor_version = 1; |
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225 | cinfo->density_unit = 0; |
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226 | cinfo->X_density = 1; |
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227 | cinfo->Y_density = 1; |
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228 | cinfo->saw_Adobe_marker = FALSE; |
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229 | cinfo->Adobe_transform = 0; |
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230 | |
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231 | cinfo->marker->saw_SOI = TRUE; |
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232 | |
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233 | return TRUE; |
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234 | } |
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235 | |
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236 | |
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237 | LOCAL(boolean) |
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238 | get_sof (j_decompress_ptr cinfo, boolean is_baseline, boolean is_prog, |
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239 | boolean is_arith) |
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240 | /* Process a SOFn marker */ |
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241 | { |
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242 | INT32 length; |
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243 | int c, ci; |
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244 | jpeg_component_info * compptr; |
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245 | INPUT_VARS(cinfo); |
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246 | |
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247 | cinfo->is_baseline = is_baseline; |
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248 | cinfo->progressive_mode = is_prog; |
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249 | cinfo->arith_code = is_arith; |
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250 | |
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251 | INPUT_2BYTES(cinfo, length, return FALSE); |
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252 | |
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253 | INPUT_BYTE(cinfo, cinfo->data_precision, return FALSE); |
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254 | INPUT_2BYTES(cinfo, cinfo->image_height, return FALSE); |
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255 | INPUT_2BYTES(cinfo, cinfo->image_width, return FALSE); |
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256 | INPUT_BYTE(cinfo, cinfo->num_components, return FALSE); |
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257 | |
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258 | length -= 8; |
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259 | |
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260 | TRACEMS4(cinfo, 1, JTRC_SOF, cinfo->unread_marker, |
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261 | (int) cinfo->image_width, (int) cinfo->image_height, |
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262 | cinfo->num_components); |
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263 | |
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264 | if (cinfo->marker->saw_SOF) |
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265 | ERREXIT(cinfo, JERR_SOF_DUPLICATE); |
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266 | |
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267 | /* We don't support files in which the image height is initially specified */ |
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268 | /* as 0 and is later redefined by DNL. As long as we have to check that, */ |
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269 | /* might as well have a general sanity check. */ |
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270 | if (cinfo->image_height <= 0 || cinfo->image_width <= 0 |
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271 | || cinfo->num_components <= 0) |
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272 | ERREXIT(cinfo, JERR_EMPTY_IMAGE); |
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273 | |
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274 | if (length != (cinfo->num_components * 3)) |
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275 | ERREXIT(cinfo, JERR_BAD_LENGTH); |
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276 | |
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277 | if (cinfo->comp_info == NULL) /* do only once, even if suspend */ |
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278 | cinfo->comp_info = (jpeg_component_info *) (*cinfo->mem->alloc_small) |
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279 | ((j_common_ptr) cinfo, JPOOL_IMAGE, |
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280 | cinfo->num_components * SIZEOF(jpeg_component_info)); |
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281 | |
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282 | for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; |
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283 | ci++, compptr++) { |
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284 | compptr->component_index = ci; |
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285 | INPUT_BYTE(cinfo, compptr->component_id, return FALSE); |
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286 | INPUT_BYTE(cinfo, c, return FALSE); |
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287 | compptr->h_samp_factor = (c >> 4) & 15; |
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288 | compptr->v_samp_factor = (c ) & 15; |
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289 | INPUT_BYTE(cinfo, compptr->quant_tbl_no, return FALSE); |
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290 | |
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291 | TRACEMS4(cinfo, 1, JTRC_SOF_COMPONENT, |
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292 | compptr->component_id, compptr->h_samp_factor, |
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293 | compptr->v_samp_factor, compptr->quant_tbl_no); |
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294 | } |
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295 | |
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296 | cinfo->marker->saw_SOF = TRUE; |
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297 | |
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298 | INPUT_SYNC(cinfo); |
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299 | return TRUE; |
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300 | } |
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301 | |
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302 | |
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303 | LOCAL(boolean) |
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304 | get_sos (j_decompress_ptr cinfo) |
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305 | /* Process a SOS marker */ |
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306 | { |
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307 | INT32 length; |
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308 | int i, ci, n, c, cc; |
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309 | jpeg_component_info * compptr; |
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310 | INPUT_VARS(cinfo); |
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311 | |
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312 | if (! cinfo->marker->saw_SOF) |
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313 | ERREXIT(cinfo, JERR_SOS_NO_SOF); |
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314 | |
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315 | INPUT_2BYTES(cinfo, length, return FALSE); |
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316 | |
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317 | INPUT_BYTE(cinfo, n, return FALSE); /* Number of components */ |
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318 | |
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319 | TRACEMS1(cinfo, 1, JTRC_SOS, n); |
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320 | |
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321 | if (length != (n * 2 + 6) || n > MAX_COMPS_IN_SCAN || |
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322 | (n == 0 && !cinfo->progressive_mode)) |
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323 | /* pseudo SOS marker only allowed in progressive mode */ |
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324 | ERREXIT(cinfo, JERR_BAD_LENGTH); |
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325 | |
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326 | cinfo->comps_in_scan = n; |
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327 | |
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328 | /* Collect the component-spec parameters */ |
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329 | |
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330 | for (i = 0; i < n; i++) { |
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331 | INPUT_BYTE(cinfo, cc, return FALSE); |
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332 | INPUT_BYTE(cinfo, c, return FALSE); |
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333 | |
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334 | for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; |
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335 | ci++, compptr++) { |
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336 | if (cc == compptr->component_id) |
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337 | goto id_found; |
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338 | } |
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339 | |
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340 | ERREXIT1(cinfo, JERR_BAD_COMPONENT_ID, cc); |
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341 | |
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342 | id_found: |
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343 | |
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344 | cinfo->cur_comp_info[i] = compptr; |
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345 | compptr->dc_tbl_no = (c >> 4) & 15; |
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346 | compptr->ac_tbl_no = (c ) & 15; |
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347 | |
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348 | TRACEMS3(cinfo, 1, JTRC_SOS_COMPONENT, cc, |
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349 | compptr->dc_tbl_no, compptr->ac_tbl_no); |
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350 | } |
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351 | |
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352 | /* Collect the additional scan parameters Ss, Se, Ah/Al. */ |
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353 | INPUT_BYTE(cinfo, c, return FALSE); |
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354 | cinfo->Ss = c; |
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355 | INPUT_BYTE(cinfo, c, return FALSE); |
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356 | cinfo->Se = c; |
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357 | INPUT_BYTE(cinfo, c, return FALSE); |
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358 | cinfo->Ah = (c >> 4) & 15; |
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359 | cinfo->Al = (c ) & 15; |
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360 | |
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361 | TRACEMS4(cinfo, 1, JTRC_SOS_PARAMS, cinfo->Ss, cinfo->Se, |
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362 | cinfo->Ah, cinfo->Al); |
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363 | |
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364 | /* Prepare to scan data & restart markers */ |
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365 | cinfo->marker->next_restart_num = 0; |
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366 | |
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367 | /* Count another (non-pseudo) SOS marker */ |
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368 | if (n) cinfo->input_scan_number++; |
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369 | |
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370 | INPUT_SYNC(cinfo); |
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371 | return TRUE; |
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372 | } |
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373 | |
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374 | |
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375 | #ifdef D_ARITH_CODING_SUPPORTED |
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376 | |
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377 | LOCAL(boolean) |
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378 | get_dac (j_decompress_ptr cinfo) |
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379 | /* Process a DAC marker */ |
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380 | { |
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381 | INT32 length; |
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382 | int index, val; |
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383 | INPUT_VARS(cinfo); |
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384 | |
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385 | INPUT_2BYTES(cinfo, length, return FALSE); |
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386 | length -= 2; |
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387 | |
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388 | while (length > 0) { |
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389 | INPUT_BYTE(cinfo, index, return FALSE); |
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390 | INPUT_BYTE(cinfo, val, return FALSE); |
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391 | |
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392 | length -= 2; |
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393 | |
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394 | TRACEMS2(cinfo, 1, JTRC_DAC, index, val); |
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395 | |
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396 | if (index < 0 || index >= (2*NUM_ARITH_TBLS)) |
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397 | ERREXIT1(cinfo, JERR_DAC_INDEX, index); |
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398 | |
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399 | if (index >= NUM_ARITH_TBLS) { /* define AC table */ |
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400 | cinfo->arith_ac_K[index-NUM_ARITH_TBLS] = (UINT8) val; |
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401 | } else { /* define DC table */ |
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402 | cinfo->arith_dc_L[index] = (UINT8) (val & 0x0F); |
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403 | cinfo->arith_dc_U[index] = (UINT8) (val >> 4); |
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404 | if (cinfo->arith_dc_L[index] > cinfo->arith_dc_U[index]) |
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405 | ERREXIT1(cinfo, JERR_DAC_VALUE, val); |
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406 | } |
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407 | } |
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408 | |
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409 | if (length != 0) |
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410 | ERREXIT(cinfo, JERR_BAD_LENGTH); |
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411 | |
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412 | INPUT_SYNC(cinfo); |
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413 | return TRUE; |
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414 | } |
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415 | |
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416 | #else /* ! D_ARITH_CODING_SUPPORTED */ |
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417 | |
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418 | #define get_dac(cinfo) skip_variable(cinfo) |
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419 | |
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420 | #endif /* D_ARITH_CODING_SUPPORTED */ |
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421 | |
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422 | |
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423 | LOCAL(boolean) |
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424 | get_dht (j_decompress_ptr cinfo) |
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425 | /* Process a DHT marker */ |
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426 | { |
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427 | INT32 length; |
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428 | UINT8 bits[17]; |
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429 | UINT8 huffval[256]; |
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430 | int i, index, count; |
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431 | JHUFF_TBL **htblptr; |
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432 | INPUT_VARS(cinfo); |
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433 | |
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434 | INPUT_2BYTES(cinfo, length, return FALSE); |
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435 | length -= 2; |
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436 | |
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437 | while (length > 16) { |
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438 | INPUT_BYTE(cinfo, index, return FALSE); |
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439 | |
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440 | TRACEMS1(cinfo, 1, JTRC_DHT, index); |
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441 | |
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442 | bits[0] = 0; |
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443 | count = 0; |
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444 | for (i = 1; i <= 16; i++) { |
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445 | INPUT_BYTE(cinfo, bits[i], return FALSE); |
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446 | count += bits[i]; |
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447 | } |
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448 | |
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449 | length -= 1 + 16; |
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450 | |
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451 | TRACEMS8(cinfo, 2, JTRC_HUFFBITS, |
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452 | bits[1], bits[2], bits[3], bits[4], |
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453 | bits[5], bits[6], bits[7], bits[8]); |
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454 | TRACEMS8(cinfo, 2, JTRC_HUFFBITS, |
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455 | bits[9], bits[10], bits[11], bits[12], |
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456 | bits[13], bits[14], bits[15], bits[16]); |
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457 | |
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458 | /* Here we just do minimal validation of the counts to avoid walking |
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459 | * off the end of our table space. jdhuff.c will check more carefully. |
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460 | */ |
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461 | if (count > 256 || ((INT32) count) > length) |
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462 | ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); |
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463 | |
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464 | for (i = 0; i < count; i++) |
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465 | INPUT_BYTE(cinfo, huffval[i], return FALSE); |
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466 | |
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467 | length -= count; |
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468 | |
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469 | if (index & 0x10) { /* AC table definition */ |
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470 | index -= 0x10; |
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471 | htblptr = &cinfo->ac_huff_tbl_ptrs[index]; |
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472 | } else { /* DC table definition */ |
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473 | htblptr = &cinfo->dc_huff_tbl_ptrs[index]; |
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474 | } |
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475 | |
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476 | if (index < 0 || index >= NUM_HUFF_TBLS) |
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477 | ERREXIT1(cinfo, JERR_DHT_INDEX, index); |
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478 | |
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479 | if (*htblptr == NULL) |
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480 | *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo); |
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481 | |
---|
482 | MEMCOPY((*htblptr)->bits, bits, SIZEOF((*htblptr)->bits)); |
---|
483 | MEMCOPY((*htblptr)->huffval, huffval, SIZEOF((*htblptr)->huffval)); |
---|
484 | } |
---|
485 | |
---|
486 | if (length != 0) |
---|
487 | ERREXIT(cinfo, JERR_BAD_LENGTH); |
---|
488 | |
---|
489 | INPUT_SYNC(cinfo); |
---|
490 | return TRUE; |
---|
491 | } |
---|
492 | |
---|
493 | |
---|
494 | LOCAL(boolean) |
---|
495 | get_dqt (j_decompress_ptr cinfo) |
---|
496 | /* Process a DQT marker */ |
---|
497 | { |
---|
498 | INT32 length, count, i; |
---|
499 | int n, prec; |
---|
500 | unsigned int tmp; |
---|
501 | JQUANT_TBL *quant_ptr; |
---|
502 | const int *natural_order; |
---|
503 | INPUT_VARS(cinfo); |
---|
504 | |
---|
505 | INPUT_2BYTES(cinfo, length, return FALSE); |
---|
506 | length -= 2; |
---|
507 | |
---|
508 | while (length > 0) { |
---|
509 | length--; |
---|
510 | INPUT_BYTE(cinfo, n, return FALSE); |
---|
511 | prec = n >> 4; |
---|
512 | n &= 0x0F; |
---|
513 | |
---|
514 | TRACEMS2(cinfo, 1, JTRC_DQT, n, prec); |
---|
515 | |
---|
516 | if (n >= NUM_QUANT_TBLS) |
---|
517 | ERREXIT1(cinfo, JERR_DQT_INDEX, n); |
---|
518 | |
---|
519 | if (cinfo->quant_tbl_ptrs[n] == NULL) |
---|
520 | cinfo->quant_tbl_ptrs[n] = jpeg_alloc_quant_table((j_common_ptr) cinfo); |
---|
521 | quant_ptr = cinfo->quant_tbl_ptrs[n]; |
---|
522 | |
---|
523 | if (prec) { |
---|
524 | if (length < DCTSIZE2 * 2) { |
---|
525 | /* Initialize full table for safety. */ |
---|
526 | for (i = 0; i < DCTSIZE2; i++) { |
---|
527 | quant_ptr->quantval[i] = 1; |
---|
528 | } |
---|
529 | count = length >> 1; |
---|
530 | } else |
---|
531 | count = DCTSIZE2; |
---|
532 | } else { |
---|
533 | if (length < DCTSIZE2) { |
---|
534 | /* Initialize full table for safety. */ |
---|
535 | for (i = 0; i < DCTSIZE2; i++) { |
---|
536 | quant_ptr->quantval[i] = 1; |
---|
537 | } |
---|
538 | count = length; |
---|
539 | } else |
---|
540 | count = DCTSIZE2; |
---|
541 | } |
---|
542 | |
---|
543 | switch (count) { |
---|
544 | case (2*2): natural_order = jpeg_natural_order2; break; |
---|
545 | case (3*3): natural_order = jpeg_natural_order3; break; |
---|
546 | case (4*4): natural_order = jpeg_natural_order4; break; |
---|
547 | case (5*5): natural_order = jpeg_natural_order5; break; |
---|
548 | case (6*6): natural_order = jpeg_natural_order6; break; |
---|
549 | case (7*7): natural_order = jpeg_natural_order7; break; |
---|
550 | default: natural_order = jpeg_natural_order; break; |
---|
551 | } |
---|
552 | |
---|
553 | for (i = 0; i < count; i++) { |
---|
554 | if (prec) |
---|
555 | INPUT_2BYTES(cinfo, tmp, return FALSE); |
---|
556 | else |
---|
557 | INPUT_BYTE(cinfo, tmp, return FALSE); |
---|
558 | /* We convert the zigzag-order table to natural array order. */ |
---|
559 | quant_ptr->quantval[natural_order[i]] = (UINT16) tmp; |
---|
560 | } |
---|
561 | |
---|
562 | if (cinfo->err->trace_level >= 2) { |
---|
563 | for (i = 0; i < DCTSIZE2; i += 8) { |
---|
564 | TRACEMS8(cinfo, 2, JTRC_QUANTVALS, |
---|
565 | quant_ptr->quantval[i], quant_ptr->quantval[i+1], |
---|
566 | quant_ptr->quantval[i+2], quant_ptr->quantval[i+3], |
---|
567 | quant_ptr->quantval[i+4], quant_ptr->quantval[i+5], |
---|
568 | quant_ptr->quantval[i+6], quant_ptr->quantval[i+7]); |
---|
569 | } |
---|
570 | } |
---|
571 | |
---|
572 | length -= count; |
---|
573 | if (prec) length -= count; |
---|
574 | } |
---|
575 | |
---|
576 | if (length != 0) |
---|
577 | ERREXIT(cinfo, JERR_BAD_LENGTH); |
---|
578 | |
---|
579 | INPUT_SYNC(cinfo); |
---|
580 | return TRUE; |
---|
581 | } |
---|
582 | |
---|
583 | |
---|
584 | LOCAL(boolean) |
---|
585 | get_dri (j_decompress_ptr cinfo) |
---|
586 | /* Process a DRI marker */ |
---|
587 | { |
---|
588 | INT32 length; |
---|
589 | unsigned int tmp; |
---|
590 | INPUT_VARS(cinfo); |
---|
591 | |
---|
592 | INPUT_2BYTES(cinfo, length, return FALSE); |
---|
593 | |
---|
594 | if (length != 4) |
---|
595 | ERREXIT(cinfo, JERR_BAD_LENGTH); |
---|
596 | |
---|
597 | INPUT_2BYTES(cinfo, tmp, return FALSE); |
---|
598 | |
---|
599 | TRACEMS1(cinfo, 1, JTRC_DRI, tmp); |
---|
600 | |
---|
601 | cinfo->restart_interval = tmp; |
---|
602 | |
---|
603 | INPUT_SYNC(cinfo); |
---|
604 | return TRUE; |
---|
605 | } |
---|
606 | |
---|
607 | |
---|
608 | /* |
---|
609 | * Routines for processing APPn and COM markers. |
---|
610 | * These are either saved in memory or discarded, per application request. |
---|
611 | * APP0 and APP14 are specially checked to see if they are |
---|
612 | * JFIF and Adobe markers, respectively. |
---|
613 | */ |
---|
614 | |
---|
615 | #define APP0_DATA_LEN 14 /* Length of interesting data in APP0 */ |
---|
616 | #define APP14_DATA_LEN 12 /* Length of interesting data in APP14 */ |
---|
617 | #define APPN_DATA_LEN 14 /* Must be the largest of the above!! */ |
---|
618 | |
---|
619 | |
---|
620 | LOCAL(void) |
---|
621 | examine_app0 (j_decompress_ptr cinfo, JOCTET FAR * data, |
---|
622 | unsigned int datalen, INT32 remaining) |
---|
623 | /* Examine first few bytes from an APP0. |
---|
624 | * Take appropriate action if it is a JFIF marker. |
---|
625 | * datalen is # of bytes at data[], remaining is length of rest of marker data. |
---|
626 | */ |
---|
627 | { |
---|
628 | INT32 totallen = (INT32) datalen + remaining; |
---|
629 | |
---|
630 | if (datalen >= APP0_DATA_LEN && |
---|
631 | GETJOCTET(data[0]) == 0x4A && |
---|
632 | GETJOCTET(data[1]) == 0x46 && |
---|
633 | GETJOCTET(data[2]) == 0x49 && |
---|
634 | GETJOCTET(data[3]) == 0x46 && |
---|
635 | GETJOCTET(data[4]) == 0) { |
---|
636 | /* Found JFIF APP0 marker: save info */ |
---|
637 | cinfo->saw_JFIF_marker = TRUE; |
---|
638 | cinfo->JFIF_major_version = GETJOCTET(data[5]); |
---|
639 | cinfo->JFIF_minor_version = GETJOCTET(data[6]); |
---|
640 | cinfo->density_unit = GETJOCTET(data[7]); |
---|
641 | cinfo->X_density = (GETJOCTET(data[8]) << 8) + GETJOCTET(data[9]); |
---|
642 | cinfo->Y_density = (GETJOCTET(data[10]) << 8) + GETJOCTET(data[11]); |
---|
643 | /* Check version. |
---|
644 | * Major version must be 1, anything else signals an incompatible change. |
---|
645 | * (We used to treat this as an error, but now it's a nonfatal warning, |
---|
646 | * because some bozo at Hijaak couldn't read the spec.) |
---|
647 | * Minor version should be 0..2, but process anyway if newer. |
---|
648 | */ |
---|
649 | if (cinfo->JFIF_major_version != 1) |
---|
650 | WARNMS2(cinfo, JWRN_JFIF_MAJOR, |
---|
651 | cinfo->JFIF_major_version, cinfo->JFIF_minor_version); |
---|
652 | /* Generate trace messages */ |
---|
653 | TRACEMS5(cinfo, 1, JTRC_JFIF, |
---|
654 | cinfo->JFIF_major_version, cinfo->JFIF_minor_version, |
---|
655 | cinfo->X_density, cinfo->Y_density, cinfo->density_unit); |
---|
656 | /* Validate thumbnail dimensions and issue appropriate messages */ |
---|
657 | if (GETJOCTET(data[12]) | GETJOCTET(data[13])) |
---|
658 | TRACEMS2(cinfo, 1, JTRC_JFIF_THUMBNAIL, |
---|
659 | GETJOCTET(data[12]), GETJOCTET(data[13])); |
---|
660 | totallen -= APP0_DATA_LEN; |
---|
661 | if (totallen != |
---|
662 | ((INT32)GETJOCTET(data[12]) * (INT32)GETJOCTET(data[13]) * (INT32) 3)) |
---|
663 | TRACEMS1(cinfo, 1, JTRC_JFIF_BADTHUMBNAILSIZE, (int) totallen); |
---|
664 | } else if (datalen >= 6 && |
---|
665 | GETJOCTET(data[0]) == 0x4A && |
---|
666 | GETJOCTET(data[1]) == 0x46 && |
---|
667 | GETJOCTET(data[2]) == 0x58 && |
---|
668 | GETJOCTET(data[3]) == 0x58 && |
---|
669 | GETJOCTET(data[4]) == 0) { |
---|
670 | /* Found JFIF "JFXX" extension APP0 marker */ |
---|
671 | /* The library doesn't actually do anything with these, |
---|
672 | * but we try to produce a helpful trace message. |
---|
673 | */ |
---|
674 | switch (GETJOCTET(data[5])) { |
---|
675 | case 0x10: |
---|
676 | TRACEMS1(cinfo, 1, JTRC_THUMB_JPEG, (int) totallen); |
---|
677 | break; |
---|
678 | case 0x11: |
---|
679 | TRACEMS1(cinfo, 1, JTRC_THUMB_PALETTE, (int) totallen); |
---|
680 | break; |
---|
681 | case 0x13: |
---|
682 | TRACEMS1(cinfo, 1, JTRC_THUMB_RGB, (int) totallen); |
---|
683 | break; |
---|
684 | default: |
---|
685 | TRACEMS2(cinfo, 1, JTRC_JFIF_EXTENSION, |
---|
686 | GETJOCTET(data[5]), (int) totallen); |
---|
687 | break; |
---|
688 | } |
---|
689 | } else { |
---|
690 | /* Start of APP0 does not match "JFIF" or "JFXX", or too short */ |
---|
691 | TRACEMS1(cinfo, 1, JTRC_APP0, (int) totallen); |
---|
692 | } |
---|
693 | } |
---|
694 | |
---|
695 | |
---|
696 | LOCAL(void) |
---|
697 | examine_app14 (j_decompress_ptr cinfo, JOCTET FAR * data, |
---|
698 | unsigned int datalen, INT32 remaining) |
---|
699 | /* Examine first few bytes from an APP14. |
---|
700 | * Take appropriate action if it is an Adobe marker. |
---|
701 | * datalen is # of bytes at data[], remaining is length of rest of marker data. |
---|
702 | */ |
---|
703 | { |
---|
704 | unsigned int version, flags0, flags1, transform; |
---|
705 | |
---|
706 | if (datalen >= APP14_DATA_LEN && |
---|
707 | GETJOCTET(data[0]) == 0x41 && |
---|
708 | GETJOCTET(data[1]) == 0x64 && |
---|
709 | GETJOCTET(data[2]) == 0x6F && |
---|
710 | GETJOCTET(data[3]) == 0x62 && |
---|
711 | GETJOCTET(data[4]) == 0x65) { |
---|
712 | /* Found Adobe APP14 marker */ |
---|
713 | version = (GETJOCTET(data[5]) << 8) + GETJOCTET(data[6]); |
---|
714 | flags0 = (GETJOCTET(data[7]) << 8) + GETJOCTET(data[8]); |
---|
715 | flags1 = (GETJOCTET(data[9]) << 8) + GETJOCTET(data[10]); |
---|
716 | transform = GETJOCTET(data[11]); |
---|
717 | TRACEMS4(cinfo, 1, JTRC_ADOBE, version, flags0, flags1, transform); |
---|
718 | cinfo->saw_Adobe_marker = TRUE; |
---|
719 | cinfo->Adobe_transform = (UINT8) transform; |
---|
720 | } else { |
---|
721 | /* Start of APP14 does not match "Adobe", or too short */ |
---|
722 | TRACEMS1(cinfo, 1, JTRC_APP14, (int) (datalen + remaining)); |
---|
723 | } |
---|
724 | } |
---|
725 | |
---|
726 | |
---|
727 | METHODDEF(boolean) |
---|
728 | get_interesting_appn (j_decompress_ptr cinfo) |
---|
729 | /* Process an APP0 or APP14 marker without saving it */ |
---|
730 | { |
---|
731 | INT32 length; |
---|
732 | JOCTET b[APPN_DATA_LEN]; |
---|
733 | unsigned int i, numtoread; |
---|
734 | INPUT_VARS(cinfo); |
---|
735 | |
---|
736 | INPUT_2BYTES(cinfo, length, return FALSE); |
---|
737 | length -= 2; |
---|
738 | |
---|
739 | /* get the interesting part of the marker data */ |
---|
740 | if (length >= APPN_DATA_LEN) |
---|
741 | numtoread = APPN_DATA_LEN; |
---|
742 | else if (length > 0) |
---|
743 | numtoread = (unsigned int) length; |
---|
744 | else |
---|
745 | numtoread = 0; |
---|
746 | for (i = 0; i < numtoread; i++) |
---|
747 | INPUT_BYTE(cinfo, b[i], return FALSE); |
---|
748 | length -= numtoread; |
---|
749 | |
---|
750 | /* process it */ |
---|
751 | switch (cinfo->unread_marker) { |
---|
752 | case M_APP0: |
---|
753 | examine_app0(cinfo, (JOCTET FAR *) b, numtoread, length); |
---|
754 | break; |
---|
755 | case M_APP14: |
---|
756 | examine_app14(cinfo, (JOCTET FAR *) b, numtoread, length); |
---|
757 | break; |
---|
758 | default: |
---|
759 | /* can't get here unless jpeg_save_markers chooses wrong processor */ |
---|
760 | ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker); |
---|
761 | break; |
---|
762 | } |
---|
763 | |
---|
764 | /* skip any remaining data -- could be lots */ |
---|
765 | INPUT_SYNC(cinfo); |
---|
766 | if (length > 0) |
---|
767 | (*cinfo->src->skip_input_data) (cinfo, (long) length); |
---|
768 | |
---|
769 | return TRUE; |
---|
770 | } |
---|
771 | |
---|
772 | |
---|
773 | #ifdef SAVE_MARKERS_SUPPORTED |
---|
774 | |
---|
775 | METHODDEF(boolean) |
---|
776 | save_marker (j_decompress_ptr cinfo) |
---|
777 | /* Save an APPn or COM marker into the marker list */ |
---|
778 | { |
---|
779 | my_marker_ptr marker = (my_marker_ptr) cinfo->marker; |
---|
780 | jpeg_saved_marker_ptr cur_marker = marker->cur_marker; |
---|
781 | unsigned int bytes_read, data_length; |
---|
782 | JOCTET FAR * data; |
---|
783 | INT32 length = 0; |
---|
784 | INPUT_VARS(cinfo); |
---|
785 | |
---|
786 | if (cur_marker == NULL) { |
---|
787 | /* begin reading a marker */ |
---|
788 | INPUT_2BYTES(cinfo, length, return FALSE); |
---|
789 | length -= 2; |
---|
790 | if (length >= 0) { /* watch out for bogus length word */ |
---|
791 | /* figure out how much we want to save */ |
---|
792 | unsigned int limit; |
---|
793 | if (cinfo->unread_marker == (int) M_COM) |
---|
794 | limit = marker->length_limit_COM; |
---|
795 | else |
---|
796 | limit = marker->length_limit_APPn[cinfo->unread_marker - (int) M_APP0]; |
---|
797 | if ((unsigned int) length < limit) |
---|
798 | limit = (unsigned int) length; |
---|
799 | /* allocate and initialize the marker item */ |
---|
800 | cur_marker = (jpeg_saved_marker_ptr) |
---|
801 | (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE, |
---|
802 | SIZEOF(struct jpeg_marker_struct) + limit); |
---|
803 | cur_marker->next = NULL; |
---|
804 | cur_marker->marker = (UINT8) cinfo->unread_marker; |
---|
805 | cur_marker->original_length = (unsigned int) length; |
---|
806 | cur_marker->data_length = limit; |
---|
807 | /* data area is just beyond the jpeg_marker_struct */ |
---|
808 | data = cur_marker->data = (JOCTET FAR *) (cur_marker + 1); |
---|
809 | marker->cur_marker = cur_marker; |
---|
810 | marker->bytes_read = 0; |
---|
811 | bytes_read = 0; |
---|
812 | data_length = limit; |
---|
813 | } else { |
---|
814 | /* deal with bogus length word */ |
---|
815 | bytes_read = data_length = 0; |
---|
816 | data = NULL; |
---|
817 | } |
---|
818 | } else { |
---|
819 | /* resume reading a marker */ |
---|
820 | bytes_read = marker->bytes_read; |
---|
821 | data_length = cur_marker->data_length; |
---|
822 | data = cur_marker->data + bytes_read; |
---|
823 | } |
---|
824 | |
---|
825 | while (bytes_read < data_length) { |
---|
826 | INPUT_SYNC(cinfo); /* move the restart point to here */ |
---|
827 | marker->bytes_read = bytes_read; |
---|
828 | /* If there's not at least one byte in buffer, suspend */ |
---|
829 | MAKE_BYTE_AVAIL(cinfo, return FALSE); |
---|
830 | /* Copy bytes with reasonable rapidity */ |
---|
831 | while (bytes_read < data_length && bytes_in_buffer > 0) { |
---|
832 | *data++ = *next_input_byte++; |
---|
833 | bytes_in_buffer--; |
---|
834 | bytes_read++; |
---|
835 | } |
---|
836 | } |
---|
837 | |
---|
838 | /* Done reading what we want to read */ |
---|
839 | if (cur_marker != NULL) { /* will be NULL if bogus length word */ |
---|
840 | /* Add new marker to end of list */ |
---|
841 | if (cinfo->marker_list == NULL) { |
---|
842 | cinfo->marker_list = cur_marker; |
---|
843 | } else { |
---|
844 | jpeg_saved_marker_ptr prev = cinfo->marker_list; |
---|
845 | while (prev->next != NULL) |
---|
846 | prev = prev->next; |
---|
847 | prev->next = cur_marker; |
---|
848 | } |
---|
849 | /* Reset pointer & calc remaining data length */ |
---|
850 | data = cur_marker->data; |
---|
851 | length = cur_marker->original_length - data_length; |
---|
852 | } |
---|
853 | /* Reset to initial state for next marker */ |
---|
854 | marker->cur_marker = NULL; |
---|
855 | |
---|
856 | /* Process the marker if interesting; else just make a generic trace msg */ |
---|
857 | switch (cinfo->unread_marker) { |
---|
858 | case M_APP0: |
---|
859 | examine_app0(cinfo, data, data_length, length); |
---|
860 | break; |
---|
861 | case M_APP14: |
---|
862 | examine_app14(cinfo, data, data_length, length); |
---|
863 | break; |
---|
864 | default: |
---|
865 | TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker, |
---|
866 | (int) (data_length + length)); |
---|
867 | break; |
---|
868 | } |
---|
869 | |
---|
870 | /* skip any remaining data -- could be lots */ |
---|
871 | INPUT_SYNC(cinfo); /* do before skip_input_data */ |
---|
872 | if (length > 0) |
---|
873 | (*cinfo->src->skip_input_data) (cinfo, (long) length); |
---|
874 | |
---|
875 | return TRUE; |
---|
876 | } |
---|
877 | |
---|
878 | #endif /* SAVE_MARKERS_SUPPORTED */ |
---|
879 | |
---|
880 | |
---|
881 | METHODDEF(boolean) |
---|
882 | skip_variable (j_decompress_ptr cinfo) |
---|
883 | /* Skip over an unknown or uninteresting variable-length marker */ |
---|
884 | { |
---|
885 | INT32 length; |
---|
886 | INPUT_VARS(cinfo); |
---|
887 | |
---|
888 | INPUT_2BYTES(cinfo, length, return FALSE); |
---|
889 | length -= 2; |
---|
890 | |
---|
891 | TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker, (int) length); |
---|
892 | |
---|
893 | INPUT_SYNC(cinfo); /* do before skip_input_data */ |
---|
894 | if (length > 0) |
---|
895 | (*cinfo->src->skip_input_data) (cinfo, (long) length); |
---|
896 | |
---|
897 | return TRUE; |
---|
898 | } |
---|
899 | |
---|
900 | |
---|
901 | /* |
---|
902 | * Find the next JPEG marker, save it in cinfo->unread_marker. |
---|
903 | * Returns FALSE if had to suspend before reaching a marker; |
---|
904 | * in that case cinfo->unread_marker is unchanged. |
---|
905 | * |
---|
906 | * Note that the result might not be a valid marker code, |
---|
907 | * but it will never be 0 or FF. |
---|
908 | */ |
---|
909 | |
---|
910 | LOCAL(boolean) |
---|
911 | next_marker (j_decompress_ptr cinfo) |
---|
912 | { |
---|
913 | int c; |
---|
914 | INPUT_VARS(cinfo); |
---|
915 | |
---|
916 | for (;;) { |
---|
917 | INPUT_BYTE(cinfo, c, return FALSE); |
---|
918 | /* Skip any non-FF bytes. |
---|
919 | * This may look a bit inefficient, but it will not occur in a valid file. |
---|
920 | * We sync after each discarded byte so that a suspending data source |
---|
921 | * can discard the byte from its buffer. |
---|
922 | */ |
---|
923 | while (c != 0xFF) { |
---|
924 | cinfo->marker->discarded_bytes++; |
---|
925 | INPUT_SYNC(cinfo); |
---|
926 | INPUT_BYTE(cinfo, c, return FALSE); |
---|
927 | } |
---|
928 | /* This loop swallows any duplicate FF bytes. Extra FFs are legal as |
---|
929 | * pad bytes, so don't count them in discarded_bytes. We assume there |
---|
930 | * will not be so many consecutive FF bytes as to overflow a suspending |
---|
931 | * data source's input buffer. |
---|
932 | */ |
---|
933 | do { |
---|
934 | INPUT_BYTE(cinfo, c, return FALSE); |
---|
935 | } while (c == 0xFF); |
---|
936 | if (c != 0) |
---|
937 | break; /* found a valid marker, exit loop */ |
---|
938 | /* Reach here if we found a stuffed-zero data sequence (FF/00). |
---|
939 | * Discard it and loop back to try again. |
---|
940 | */ |
---|
941 | cinfo->marker->discarded_bytes += 2; |
---|
942 | INPUT_SYNC(cinfo); |
---|
943 | } |
---|
944 | |
---|
945 | if (cinfo->marker->discarded_bytes != 0) { |
---|
946 | WARNMS2(cinfo, JWRN_EXTRANEOUS_DATA, cinfo->marker->discarded_bytes, c); |
---|
947 | cinfo->marker->discarded_bytes = 0; |
---|
948 | } |
---|
949 | |
---|
950 | cinfo->unread_marker = c; |
---|
951 | |
---|
952 | INPUT_SYNC(cinfo); |
---|
953 | return TRUE; |
---|
954 | } |
---|
955 | |
---|
956 | |
---|
957 | LOCAL(boolean) |
---|
958 | first_marker (j_decompress_ptr cinfo) |
---|
959 | /* Like next_marker, but used to obtain the initial SOI marker. */ |
---|
960 | /* For this marker, we do not allow preceding garbage or fill; otherwise, |
---|
961 | * we might well scan an entire input file before realizing it ain't JPEG. |
---|
962 | * If an application wants to process non-JFIF files, it must seek to the |
---|
963 | * SOI before calling the JPEG library. |
---|
964 | */ |
---|
965 | { |
---|
966 | int c, c2; |
---|
967 | INPUT_VARS(cinfo); |
---|
968 | |
---|
969 | INPUT_BYTE(cinfo, c, return FALSE); |
---|
970 | INPUT_BYTE(cinfo, c2, return FALSE); |
---|
971 | if (c != 0xFF || c2 != (int) M_SOI) |
---|
972 | ERREXIT2(cinfo, JERR_NO_SOI, c, c2); |
---|
973 | |
---|
974 | cinfo->unread_marker = c2; |
---|
975 | |
---|
976 | INPUT_SYNC(cinfo); |
---|
977 | return TRUE; |
---|
978 | } |
---|
979 | |
---|
980 | |
---|
981 | /* |
---|
982 | * Read markers until SOS or EOI. |
---|
983 | * |
---|
984 | * Returns same codes as are defined for jpeg_consume_input: |
---|
985 | * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI. |
---|
986 | * |
---|
987 | * Note: This function may return a pseudo SOS marker (with zero |
---|
988 | * component number) for treat by input controller's consume_input. |
---|
989 | * consume_input itself should filter out (skip) the pseudo marker |
---|
990 | * after processing for the caller. |
---|
991 | */ |
---|
992 | |
---|
993 | METHODDEF(int) |
---|
994 | read_markers (j_decompress_ptr cinfo) |
---|
995 | { |
---|
996 | /* Outer loop repeats once for each marker. */ |
---|
997 | for (;;) { |
---|
998 | /* Collect the marker proper, unless we already did. */ |
---|
999 | /* NB: first_marker() enforces the requirement that SOI appear first. */ |
---|
1000 | if (cinfo->unread_marker == 0) { |
---|
1001 | if (! cinfo->marker->saw_SOI) { |
---|
1002 | if (! first_marker(cinfo)) |
---|
1003 | return JPEG_SUSPENDED; |
---|
1004 | } else { |
---|
1005 | if (! next_marker(cinfo)) |
---|
1006 | return JPEG_SUSPENDED; |
---|
1007 | } |
---|
1008 | } |
---|
1009 | /* At this point cinfo->unread_marker contains the marker code and the |
---|
1010 | * input point is just past the marker proper, but before any parameters. |
---|
1011 | * A suspension will cause us to return with this state still true. |
---|
1012 | */ |
---|
1013 | switch (cinfo->unread_marker) { |
---|
1014 | case M_SOI: |
---|
1015 | if (! get_soi(cinfo)) |
---|
1016 | return JPEG_SUSPENDED; |
---|
1017 | break; |
---|
1018 | |
---|
1019 | case M_SOF0: /* Baseline */ |
---|
1020 | if (! get_sof(cinfo, TRUE, FALSE, FALSE)) |
---|
1021 | return JPEG_SUSPENDED; |
---|
1022 | break; |
---|
1023 | |
---|
1024 | case M_SOF1: /* Extended sequential, Huffman */ |
---|
1025 | if (! get_sof(cinfo, FALSE, FALSE, FALSE)) |
---|
1026 | return JPEG_SUSPENDED; |
---|
1027 | break; |
---|
1028 | |
---|
1029 | case M_SOF2: /* Progressive, Huffman */ |
---|
1030 | if (! get_sof(cinfo, FALSE, TRUE, FALSE)) |
---|
1031 | return JPEG_SUSPENDED; |
---|
1032 | break; |
---|
1033 | |
---|
1034 | case M_SOF9: /* Extended sequential, arithmetic */ |
---|
1035 | if (! get_sof(cinfo, FALSE, FALSE, TRUE)) |
---|
1036 | return JPEG_SUSPENDED; |
---|
1037 | break; |
---|
1038 | |
---|
1039 | case M_SOF10: /* Progressive, arithmetic */ |
---|
1040 | if (! get_sof(cinfo, FALSE, TRUE, TRUE)) |
---|
1041 | return JPEG_SUSPENDED; |
---|
1042 | break; |
---|
1043 | |
---|
1044 | /* Currently unsupported SOFn types */ |
---|
1045 | case M_SOF3: /* Lossless, Huffman */ |
---|
1046 | case M_SOF5: /* Differential sequential, Huffman */ |
---|
1047 | case M_SOF6: /* Differential progressive, Huffman */ |
---|
1048 | case M_SOF7: /* Differential lossless, Huffman */ |
---|
1049 | case M_JPG: /* Reserved for JPEG extensions */ |
---|
1050 | case M_SOF11: /* Lossless, arithmetic */ |
---|
1051 | case M_SOF13: /* Differential sequential, arithmetic */ |
---|
1052 | case M_SOF14: /* Differential progressive, arithmetic */ |
---|
1053 | case M_SOF15: /* Differential lossless, arithmetic */ |
---|
1054 | ERREXIT1(cinfo, JERR_SOF_UNSUPPORTED, cinfo->unread_marker); |
---|
1055 | break; |
---|
1056 | |
---|
1057 | case M_SOS: |
---|
1058 | if (! get_sos(cinfo)) |
---|
1059 | return JPEG_SUSPENDED; |
---|
1060 | cinfo->unread_marker = 0; /* processed the marker */ |
---|
1061 | return JPEG_REACHED_SOS; |
---|
1062 | |
---|
1063 | case M_EOI: |
---|
1064 | TRACEMS(cinfo, 1, JTRC_EOI); |
---|
1065 | cinfo->unread_marker = 0; /* processed the marker */ |
---|
1066 | return JPEG_REACHED_EOI; |
---|
1067 | |
---|
1068 | case M_DAC: |
---|
1069 | if (! get_dac(cinfo)) |
---|
1070 | return JPEG_SUSPENDED; |
---|
1071 | break; |
---|
1072 | |
---|
1073 | case M_DHT: |
---|
1074 | if (! get_dht(cinfo)) |
---|
1075 | return JPEG_SUSPENDED; |
---|
1076 | break; |
---|
1077 | |
---|
1078 | case M_DQT: |
---|
1079 | if (! get_dqt(cinfo)) |
---|
1080 | return JPEG_SUSPENDED; |
---|
1081 | break; |
---|
1082 | |
---|
1083 | case M_DRI: |
---|
1084 | if (! get_dri(cinfo)) |
---|
1085 | return JPEG_SUSPENDED; |
---|
1086 | break; |
---|
1087 | |
---|
1088 | case M_APP0: |
---|
1089 | case M_APP1: |
---|
1090 | case M_APP2: |
---|
1091 | case M_APP3: |
---|
1092 | case M_APP4: |
---|
1093 | case M_APP5: |
---|
1094 | case M_APP6: |
---|
1095 | case M_APP7: |
---|
1096 | case M_APP8: |
---|
1097 | case M_APP9: |
---|
1098 | case M_APP10: |
---|
1099 | case M_APP11: |
---|
1100 | case M_APP12: |
---|
1101 | case M_APP13: |
---|
1102 | case M_APP14: |
---|
1103 | case M_APP15: |
---|
1104 | if (! (*((my_marker_ptr) cinfo->marker)->process_APPn[ |
---|
1105 | cinfo->unread_marker - (int) M_APP0]) (cinfo)) |
---|
1106 | return JPEG_SUSPENDED; |
---|
1107 | break; |
---|
1108 | |
---|
1109 | case M_COM: |
---|
1110 | if (! (*((my_marker_ptr) cinfo->marker)->process_COM) (cinfo)) |
---|
1111 | return JPEG_SUSPENDED; |
---|
1112 | break; |
---|
1113 | |
---|
1114 | case M_RST0: /* these are all parameterless */ |
---|
1115 | case M_RST1: |
---|
1116 | case M_RST2: |
---|
1117 | case M_RST3: |
---|
1118 | case M_RST4: |
---|
1119 | case M_RST5: |
---|
1120 | case M_RST6: |
---|
1121 | case M_RST7: |
---|
1122 | case M_TEM: |
---|
1123 | TRACEMS1(cinfo, 1, JTRC_PARMLESS_MARKER, cinfo->unread_marker); |
---|
1124 | break; |
---|
1125 | |
---|
1126 | case M_DNL: /* Ignore DNL ... perhaps the wrong thing */ |
---|
1127 | if (! skip_variable(cinfo)) |
---|
1128 | return JPEG_SUSPENDED; |
---|
1129 | break; |
---|
1130 | |
---|
1131 | default: /* must be DHP, EXP, JPGn, or RESn */ |
---|
1132 | /* For now, we treat the reserved markers as fatal errors since they are |
---|
1133 | * likely to be used to signal incompatible JPEG Part 3 extensions. |
---|
1134 | * Once the JPEG 3 version-number marker is well defined, this code |
---|
1135 | * ought to change! |
---|
1136 | */ |
---|
1137 | ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker); |
---|
1138 | break; |
---|
1139 | } |
---|
1140 | /* Successfully processed marker, so reset state variable */ |
---|
1141 | cinfo->unread_marker = 0; |
---|
1142 | } /* end loop */ |
---|
1143 | } |
---|
1144 | |
---|
1145 | |
---|
1146 | /* |
---|
1147 | * Read a restart marker, which is expected to appear next in the datastream; |
---|
1148 | * if the marker is not there, take appropriate recovery action. |
---|
1149 | * Returns FALSE if suspension is required. |
---|
1150 | * |
---|
1151 | * This is called by the entropy decoder after it has read an appropriate |
---|
1152 | * number of MCUs. cinfo->unread_marker may be nonzero if the entropy decoder |
---|
1153 | * has already read a marker from the data source. Under normal conditions |
---|
1154 | * cinfo->unread_marker will be reset to 0 before returning; if not reset, |
---|
1155 | * it holds a marker which the decoder will be unable to read past. |
---|
1156 | */ |
---|
1157 | |
---|
1158 | METHODDEF(boolean) |
---|
1159 | read_restart_marker (j_decompress_ptr cinfo) |
---|
1160 | { |
---|
1161 | /* Obtain a marker unless we already did. */ |
---|
1162 | /* Note that next_marker will complain if it skips any data. */ |
---|
1163 | if (cinfo->unread_marker == 0) { |
---|
1164 | if (! next_marker(cinfo)) |
---|
1165 | return FALSE; |
---|
1166 | } |
---|
1167 | |
---|
1168 | if (cinfo->unread_marker == |
---|
1169 | ((int) M_RST0 + cinfo->marker->next_restart_num)) { |
---|
1170 | /* Normal case --- swallow the marker and let entropy decoder continue */ |
---|
1171 | TRACEMS1(cinfo, 3, JTRC_RST, cinfo->marker->next_restart_num); |
---|
1172 | cinfo->unread_marker = 0; |
---|
1173 | } else { |
---|
1174 | /* Uh-oh, the restart markers have been messed up. */ |
---|
1175 | /* Let the data source manager determine how to resync. */ |
---|
1176 | if (! (*cinfo->src->resync_to_restart) (cinfo, |
---|
1177 | cinfo->marker->next_restart_num)) |
---|
1178 | return FALSE; |
---|
1179 | } |
---|
1180 | |
---|
1181 | /* Update next-restart state */ |
---|
1182 | cinfo->marker->next_restart_num = (cinfo->marker->next_restart_num + 1) & 7; |
---|
1183 | |
---|
1184 | return TRUE; |
---|
1185 | } |
---|
1186 | |
---|
1187 | |
---|
1188 | /* |
---|
1189 | * This is the default resync_to_restart method for data source managers |
---|
1190 | * to use if they don't have any better approach. Some data source managers |
---|
1191 | * may be able to back up, or may have additional knowledge about the data |
---|
1192 | * which permits a more intelligent recovery strategy; such managers would |
---|
1193 | * presumably supply their own resync method. |
---|
1194 | * |
---|
1195 | * read_restart_marker calls resync_to_restart if it finds a marker other than |
---|
1196 | * the restart marker it was expecting. (This code is *not* used unless |
---|
1197 | * a nonzero restart interval has been declared.) cinfo->unread_marker is |
---|
1198 | * the marker code actually found (might be anything, except 0 or FF). |
---|
1199 | * The desired restart marker number (0..7) is passed as a parameter. |
---|
1200 | * This routine is supposed to apply whatever error recovery strategy seems |
---|
1201 | * appropriate in order to position the input stream to the next data segment. |
---|
1202 | * Note that cinfo->unread_marker is treated as a marker appearing before |
---|
1203 | * the current data-source input point; usually it should be reset to zero |
---|
1204 | * before returning. |
---|
1205 | * Returns FALSE if suspension is required. |
---|
1206 | * |
---|
1207 | * This implementation is substantially constrained by wanting to treat the |
---|
1208 | * input as a data stream; this means we can't back up. Therefore, we have |
---|
1209 | * only the following actions to work with: |
---|
1210 | * 1. Simply discard the marker and let the entropy decoder resume at next |
---|
1211 | * byte of file. |
---|
1212 | * 2. Read forward until we find another marker, discarding intervening |
---|
1213 | * data. (In theory we could look ahead within the current bufferload, |
---|
1214 | * without having to discard data if we don't find the desired marker. |
---|
1215 | * This idea is not implemented here, in part because it makes behavior |
---|
1216 | * dependent on buffer size and chance buffer-boundary positions.) |
---|
1217 | * 3. Leave the marker unread (by failing to zero cinfo->unread_marker). |
---|
1218 | * This will cause the entropy decoder to process an empty data segment, |
---|
1219 | * inserting dummy zeroes, and then we will reprocess the marker. |
---|
1220 | * |
---|
1221 | * #2 is appropriate if we think the desired marker lies ahead, while #3 is |
---|
1222 | * appropriate if the found marker is a future restart marker (indicating |
---|
1223 | * that we have missed the desired restart marker, probably because it got |
---|
1224 | * corrupted). |
---|
1225 | * We apply #2 or #3 if the found marker is a restart marker no more than |
---|
1226 | * two counts behind or ahead of the expected one. We also apply #2 if the |
---|
1227 | * found marker is not a legal JPEG marker code (it's certainly bogus data). |
---|
1228 | * If the found marker is a restart marker more than 2 counts away, we do #1 |
---|
1229 | * (too much risk that the marker is erroneous; with luck we will be able to |
---|
1230 | * resync at some future point). |
---|
1231 | * For any valid non-restart JPEG marker, we apply #3. This keeps us from |
---|
1232 | * overrunning the end of a scan. An implementation limited to single-scan |
---|
1233 | * files might find it better to apply #2 for markers other than EOI, since |
---|
1234 | * any other marker would have to be bogus data in that case. |
---|
1235 | */ |
---|
1236 | |
---|
1237 | GLOBAL(boolean) |
---|
1238 | jpeg_resync_to_restart (j_decompress_ptr cinfo, int desired) |
---|
1239 | { |
---|
1240 | int marker = cinfo->unread_marker; |
---|
1241 | int action = 1; |
---|
1242 | |
---|
1243 | /* Always put up a warning. */ |
---|
1244 | WARNMS2(cinfo, JWRN_MUST_RESYNC, marker, desired); |
---|
1245 | |
---|
1246 | /* Outer loop handles repeated decision after scanning forward. */ |
---|
1247 | for (;;) { |
---|
1248 | if (marker < (int) M_SOF0) |
---|
1249 | action = 2; /* invalid marker */ |
---|
1250 | else if (marker < (int) M_RST0 || marker > (int) M_RST7) |
---|
1251 | action = 3; /* valid non-restart marker */ |
---|
1252 | else { |
---|
1253 | if (marker == ((int) M_RST0 + ((desired+1) & 7)) || |
---|
1254 | marker == ((int) M_RST0 + ((desired+2) & 7))) |
---|
1255 | action = 3; /* one of the next two expected restarts */ |
---|
1256 | else if (marker == ((int) M_RST0 + ((desired-1) & 7)) || |
---|
1257 | marker == ((int) M_RST0 + ((desired-2) & 7))) |
---|
1258 | action = 2; /* a prior restart, so advance */ |
---|
1259 | else |
---|
1260 | action = 1; /* desired restart or too far away */ |
---|
1261 | } |
---|
1262 | TRACEMS2(cinfo, 4, JTRC_RECOVERY_ACTION, marker, action); |
---|
1263 | switch (action) { |
---|
1264 | case 1: |
---|
1265 | /* Discard marker and let entropy decoder resume processing. */ |
---|
1266 | cinfo->unread_marker = 0; |
---|
1267 | return TRUE; |
---|
1268 | case 2: |
---|
1269 | /* Scan to the next marker, and repeat the decision loop. */ |
---|
1270 | if (! next_marker(cinfo)) |
---|
1271 | return FALSE; |
---|
1272 | marker = cinfo->unread_marker; |
---|
1273 | break; |
---|
1274 | case 3: |
---|
1275 | /* Return without advancing past this marker. */ |
---|
1276 | /* Entropy decoder will be forced to process an empty segment. */ |
---|
1277 | return TRUE; |
---|
1278 | } |
---|
1279 | } /* end loop */ |
---|
1280 | } |
---|
1281 | |
---|
1282 | |
---|
1283 | /* |
---|
1284 | * Reset marker processing state to begin a fresh datastream. |
---|
1285 | */ |
---|
1286 | |
---|
1287 | METHODDEF(void) |
---|
1288 | reset_marker_reader (j_decompress_ptr cinfo) |
---|
1289 | { |
---|
1290 | my_marker_ptr marker = (my_marker_ptr) cinfo->marker; |
---|
1291 | |
---|
1292 | cinfo->comp_info = NULL; /* until allocated by get_sof */ |
---|
1293 | cinfo->input_scan_number = 0; /* no SOS seen yet */ |
---|
1294 | cinfo->unread_marker = 0; /* no pending marker */ |
---|
1295 | marker->pub.saw_SOI = FALSE; /* set internal state too */ |
---|
1296 | marker->pub.saw_SOF = FALSE; |
---|
1297 | marker->pub.discarded_bytes = 0; |
---|
1298 | marker->cur_marker = NULL; |
---|
1299 | } |
---|
1300 | |
---|
1301 | |
---|
1302 | /* |
---|
1303 | * Initialize the marker reader module. |
---|
1304 | * This is called only once, when the decompression object is created. |
---|
1305 | */ |
---|
1306 | |
---|
1307 | GLOBAL(void) |
---|
1308 | jinit_marker_reader (j_decompress_ptr cinfo) |
---|
1309 | { |
---|
1310 | my_marker_ptr marker; |
---|
1311 | int i; |
---|
1312 | |
---|
1313 | /* Create subobject in permanent pool */ |
---|
1314 | marker = (my_marker_ptr) |
---|
1315 | (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, |
---|
1316 | SIZEOF(my_marker_reader)); |
---|
1317 | cinfo->marker = (struct jpeg_marker_reader *) marker; |
---|
1318 | /* Initialize public method pointers */ |
---|
1319 | marker->pub.reset_marker_reader = reset_marker_reader; |
---|
1320 | marker->pub.read_markers = read_markers; |
---|
1321 | marker->pub.read_restart_marker = read_restart_marker; |
---|
1322 | /* Initialize COM/APPn processing. |
---|
1323 | * By default, we examine and then discard APP0 and APP14, |
---|
1324 | * but simply discard COM and all other APPn. |
---|
1325 | */ |
---|
1326 | marker->process_COM = skip_variable; |
---|
1327 | marker->length_limit_COM = 0; |
---|
1328 | for (i = 0; i < 16; i++) { |
---|
1329 | marker->process_APPn[i] = skip_variable; |
---|
1330 | marker->length_limit_APPn[i] = 0; |
---|
1331 | } |
---|
1332 | marker->process_APPn[0] = get_interesting_appn; |
---|
1333 | marker->process_APPn[14] = get_interesting_appn; |
---|
1334 | /* Reset marker processing state */ |
---|
1335 | reset_marker_reader(cinfo); |
---|
1336 | } |
---|
1337 | |
---|
1338 | |
---|
1339 | /* |
---|
1340 | * Control saving of COM and APPn markers into marker_list. |
---|
1341 | */ |
---|
1342 | |
---|
1343 | #ifdef SAVE_MARKERS_SUPPORTED |
---|
1344 | |
---|
1345 | GLOBAL(void) |
---|
1346 | jpeg_save_markers (j_decompress_ptr cinfo, int marker_code, |
---|
1347 | unsigned int length_limit) |
---|
1348 | { |
---|
1349 | my_marker_ptr marker = (my_marker_ptr) cinfo->marker; |
---|
1350 | long maxlength; |
---|
1351 | jpeg_marker_parser_method processor; |
---|
1352 | |
---|
1353 | /* Length limit mustn't be larger than what we can allocate |
---|
1354 | * (should only be a concern in a 16-bit environment). |
---|
1355 | */ |
---|
1356 | maxlength = cinfo->mem->max_alloc_chunk - SIZEOF(struct jpeg_marker_struct); |
---|
1357 | if (((long) length_limit) > maxlength) |
---|
1358 | length_limit = (unsigned int) maxlength; |
---|
1359 | |
---|
1360 | /* Choose processor routine to use. |
---|
1361 | * APP0/APP14 have special requirements. |
---|
1362 | */ |
---|
1363 | if (length_limit) { |
---|
1364 | processor = save_marker; |
---|
1365 | /* If saving APP0/APP14, save at least enough for our internal use. */ |
---|
1366 | if (marker_code == (int) M_APP0 && length_limit < APP0_DATA_LEN) |
---|
1367 | length_limit = APP0_DATA_LEN; |
---|
1368 | else if (marker_code == (int) M_APP14 && length_limit < APP14_DATA_LEN) |
---|
1369 | length_limit = APP14_DATA_LEN; |
---|
1370 | } else { |
---|
1371 | processor = skip_variable; |
---|
1372 | /* If discarding APP0/APP14, use our regular on-the-fly processor. */ |
---|
1373 | if (marker_code == (int) M_APP0 || marker_code == (int) M_APP14) |
---|
1374 | processor = get_interesting_appn; |
---|
1375 | } |
---|
1376 | |
---|
1377 | if (marker_code == (int) M_COM) { |
---|
1378 | marker->process_COM = processor; |
---|
1379 | marker->length_limit_COM = length_limit; |
---|
1380 | } else if (marker_code >= (int) M_APP0 && marker_code <= (int) M_APP15) { |
---|
1381 | marker->process_APPn[marker_code - (int) M_APP0] = processor; |
---|
1382 | marker->length_limit_APPn[marker_code - (int) M_APP0] = length_limit; |
---|
1383 | } else |
---|
1384 | ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, marker_code); |
---|
1385 | } |
---|
1386 | |
---|
1387 | #endif /* SAVE_MARKERS_SUPPORTED */ |
---|
1388 | |
---|
1389 | |
---|
1390 | /* |
---|
1391 | * Install a special processing method for COM or APPn markers. |
---|
1392 | */ |
---|
1393 | |
---|
1394 | GLOBAL(void) |
---|
1395 | jpeg_set_marker_processor (j_decompress_ptr cinfo, int marker_code, |
---|
1396 | jpeg_marker_parser_method routine) |
---|
1397 | { |
---|
1398 | my_marker_ptr marker = (my_marker_ptr) cinfo->marker; |
---|
1399 | |
---|
1400 | if (marker_code == (int) M_COM) |
---|
1401 | marker->process_COM = routine; |
---|
1402 | else if (marker_code >= (int) M_APP0 && marker_code <= (int) M_APP15) |
---|
1403 | marker->process_APPn[marker_code - (int) M_APP0] = routine; |
---|
1404 | else |
---|
1405 | ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, marker_code); |
---|
1406 | } |
---|