4 * Copyright (C) 1991-1998, Thomas G. Lane.
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5 * Modified 2002-2010 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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9 * This file defines the application interface for the JPEG library.
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10 * Most applications using the library need only include this file,
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11 * and perhaps jerror.h if they want to know the exact error codes.
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18 * First we include the configuration files that record how this
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19 * installation of the JPEG library is set up. jconfig.h can be
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20 * generated automatically for many systems. jmorecfg.h contains
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21 * manual configuration options that most people need not worry about.
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24 #ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */
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25 #include "jconfig.h" /* widely used configuration options */
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27 #include "jmorecfg.h" /* seldom changed options */
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31 #ifndef DONT_USE_EXTERN_C
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36 /* Version IDs for the JPEG library.
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37 * Might be useful for tests like "#if JPEG_LIB_VERSION >= 80".
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40 #define JPEG_LIB_VERSION 80 /* Compatibility version 8.0 */
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41 #define JPEG_LIB_VERSION_MAJOR 8
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42 #define JPEG_LIB_VERSION_MINOR 3
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45 /* Various constants determining the sizes of things.
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46 * All of these are specified by the JPEG standard, so don't change them
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47 * if you want to be compatible.
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50 #define DCTSIZE 8 /* The basic DCT block is 8x8 samples */
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51 #define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */
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52 #define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */
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53 #define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */
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54 #define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */
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55 #define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */
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56 #define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */
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57 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;
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58 * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.
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59 * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU
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60 * to handle it. We even let you do this from the jconfig.h file. However,
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61 * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe
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62 * sometimes emits noncompliant files doesn't mean you should too.
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64 #define C_MAX_BLOCKS_IN_MCU 10 /* compressor's limit on blocks per MCU */
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65 #ifndef D_MAX_BLOCKS_IN_MCU
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66 #define D_MAX_BLOCKS_IN_MCU 10 /* decompressor's limit on blocks per MCU */
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70 /* Data structures for images (arrays of samples and of DCT coefficients).
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71 * On 80x86 machines, the image arrays are too big for near pointers,
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72 * but the pointer arrays can fit in near memory.
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75 typedef JSAMPLE FAR *JSAMPROW; /* ptr to one image row of pixel samples. */
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76 typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */
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77 typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */
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79 typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */
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80 typedef JBLOCK FAR *JBLOCKROW; /* pointer to one row of coefficient blocks */
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81 typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */
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82 typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */
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84 typedef JCOEF FAR *JCOEFPTR; /* useful in a couple of places */
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87 /* Types for JPEG compression parameters and working tables. */
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90 /* DCT coefficient quantization tables. */
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93 /* This array gives the coefficient quantizers in natural array order
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94 * (not the zigzag order in which they are stored in a JPEG DQT marker).
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95 * CAUTION: IJG versions prior to v6a kept this array in zigzag order.
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97 UINT16 quantval[DCTSIZE2]; /* quantization step for each coefficient */
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98 /* This field is used only during compression. It's initialized FALSE when
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99 * the table is created, and set TRUE when it's been output to the file.
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100 * You could suppress output of a table by setting this to TRUE.
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101 * (See jpeg_suppress_tables for an example.)
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103 boolean sent_table; /* TRUE when table has been output */
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107 /* Huffman coding tables. */
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110 /* These two fields directly represent the contents of a JPEG DHT marker */
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111 UINT8 bits[17]; /* bits[k] = # of symbols with codes of */
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112 /* length k bits; bits[0] is unused */
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113 UINT8 huffval[256]; /* The symbols, in order of incr code length */
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114 /* This field is used only during compression. It's initialized FALSE when
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115 * the table is created, and set TRUE when it's been output to the file.
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116 * You could suppress output of a table by setting this to TRUE.
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117 * (See jpeg_suppress_tables for an example.)
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119 boolean sent_table; /* TRUE when table has been output */
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123 /* Basic info about one component (color channel). */
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126 /* These values are fixed over the whole image. */
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127 /* For compression, they must be supplied by parameter setup; */
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128 /* for decompression, they are read from the SOF marker. */
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129 int component_id; /* identifier for this component (0..255) */
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130 int component_index; /* its index in SOF or cinfo->comp_info[] */
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131 int h_samp_factor; /* horizontal sampling factor (1..4) */
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132 int v_samp_factor; /* vertical sampling factor (1..4) */
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133 int quant_tbl_no; /* quantization table selector (0..3) */
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134 /* These values may vary between scans. */
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135 /* For compression, they must be supplied by parameter setup; */
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136 /* for decompression, they are read from the SOS marker. */
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137 /* The decompressor output side may not use these variables. */
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138 int dc_tbl_no; /* DC entropy table selector (0..3) */
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139 int ac_tbl_no; /* AC entropy table selector (0..3) */
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141 /* Remaining fields should be treated as private by applications. */
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143 /* These values are computed during compression or decompression startup: */
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144 /* Component's size in DCT blocks.
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145 * Any dummy blocks added to complete an MCU are not counted; therefore
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146 * these values do not depend on whether a scan is interleaved or not.
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148 JDIMENSION width_in_blocks;
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149 JDIMENSION height_in_blocks;
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150 /* Size of a DCT block in samples,
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151 * reflecting any scaling we choose to apply during the DCT step.
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152 * Values from 1 to 16 are supported.
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153 * Note that different components may receive different DCT scalings.
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155 int DCT_h_scaled_size;
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156 int DCT_v_scaled_size;
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157 /* The downsampled dimensions are the component's actual, unpadded number
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158 * of samples at the main buffer (preprocessing/compression interface);
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159 * DCT scaling is included, so
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160 * downsampled_width = ceil(image_width * Hi/Hmax * DCT_h_scaled_size/DCTSIZE)
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161 * and similarly for height.
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163 JDIMENSION downsampled_width; /* actual width in samples */
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164 JDIMENSION downsampled_height; /* actual height in samples */
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165 /* This flag is used only for decompression. In cases where some of the
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166 * components will be ignored (eg grayscale output from YCbCr image),
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167 * we can skip most computations for the unused components.
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169 boolean component_needed; /* do we need the value of this component? */
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171 /* These values are computed before starting a scan of the component. */
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172 /* The decompressor output side may not use these variables. */
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173 int MCU_width; /* number of blocks per MCU, horizontally */
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174 int MCU_height; /* number of blocks per MCU, vertically */
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175 int MCU_blocks; /* MCU_width * MCU_height */
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176 int MCU_sample_width; /* MCU width in samples: MCU_width * DCT_h_scaled_size */
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177 int last_col_width; /* # of non-dummy blocks across in last MCU */
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178 int last_row_height; /* # of non-dummy blocks down in last MCU */
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180 /* Saved quantization table for component; NULL if none yet saved.
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181 * See jdinput.c comments about the need for this information.
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182 * This field is currently used only for decompression.
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184 JQUANT_TBL * quant_table;
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186 /* Private per-component storage for DCT or IDCT subsystem. */
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188 } jpeg_component_info;
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191 /* The script for encoding a multiple-scan file is an array of these: */
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194 int comps_in_scan; /* number of components encoded in this scan */
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195 int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */
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196 int Ss, Se; /* progressive JPEG spectral selection parms */
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197 int Ah, Al; /* progressive JPEG successive approx. parms */
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200 /* The decompressor can save APPn and COM markers in a list of these: */
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202 typedef struct jpeg_marker_struct FAR * jpeg_saved_marker_ptr;
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204 struct jpeg_marker_struct {
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205 jpeg_saved_marker_ptr next; /* next in list, or NULL */
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206 UINT8 marker; /* marker code: JPEG_COM, or JPEG_APP0+n */
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207 unsigned int original_length; /* # bytes of data in the file */
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208 unsigned int data_length; /* # bytes of data saved at data[] */
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209 JOCTET FAR * data; /* the data contained in the marker */
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210 /* the marker length word is not counted in data_length or original_length */
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213 /* Known color spaces. */
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216 JCS_UNKNOWN, /* error/unspecified */
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217 JCS_GRAYSCALE, /* monochrome */
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218 JCS_RGB, /* red/green/blue */
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219 JCS_YCbCr, /* Y/Cb/Cr (also known as YUV) */
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220 JCS_CMYK, /* C/M/Y/K */
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221 JCS_YCCK /* Y/Cb/Cr/K */
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224 /* DCT/IDCT algorithm options. */
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227 JDCT_ISLOW, /* slow but accurate integer algorithm */
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228 JDCT_IFAST, /* faster, less accurate integer method */
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229 JDCT_FLOAT /* floating-point: accurate, fast on fast HW */
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232 #ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */
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233 #define JDCT_DEFAULT JDCT_ISLOW
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235 #ifndef JDCT_FASTEST /* may be overridden in jconfig.h */
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236 #define JDCT_FASTEST JDCT_IFAST
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239 /* Dithering options for decompression. */
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242 JDITHER_NONE, /* no dithering */
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243 JDITHER_ORDERED, /* simple ordered dither */
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244 JDITHER_FS /* Floyd-Steinberg error diffusion dither */
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248 /* Common fields between JPEG compression and decompression master structs. */
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250 #define jpeg_common_fields \
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251 struct jpeg_error_mgr * err; /* Error handler module */\
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252 struct jpeg_memory_mgr * mem; /* Memory manager module */\
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253 struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\
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254 void * client_data; /* Available for use by application */\
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255 boolean is_decompressor; /* So common code can tell which is which */\
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256 int global_state /* For checking call sequence validity */
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258 /* Routines that are to be used by both halves of the library are declared
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259 * to receive a pointer to this structure. There are no actual instances of
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260 * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.
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262 struct jpeg_common_struct {
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263 jpeg_common_fields; /* Fields common to both master struct types */
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264 /* Additional fields follow in an actual jpeg_compress_struct or
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265 * jpeg_decompress_struct. All three structs must agree on these
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266 * initial fields! (This would be a lot cleaner in C++.)
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270 typedef struct jpeg_common_struct * j_common_ptr;
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271 typedef struct jpeg_compress_struct * j_compress_ptr;
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272 typedef struct jpeg_decompress_struct * j_decompress_ptr;
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275 /* Master record for a compression instance */
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277 struct jpeg_compress_struct {
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278 jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */
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280 /* Destination for compressed data */
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281 struct jpeg_destination_mgr * dest;
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283 /* Description of source image --- these fields must be filled in by
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284 * outer application before starting compression. in_color_space must
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285 * be correct before you can even call jpeg_set_defaults().
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288 JDIMENSION image_width; /* input image width */
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289 JDIMENSION image_height; /* input image height */
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290 int input_components; /* # of color components in input image */
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291 J_COLOR_SPACE in_color_space; /* colorspace of input image */
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293 double input_gamma; /* image gamma of input image */
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295 /* Compression parameters --- these fields must be set before calling
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296 * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to
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297 * initialize everything to reasonable defaults, then changing anything
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298 * the application specifically wants to change. That way you won't get
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299 * burnt when new parameters are added. Also note that there are several
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300 * helper routines to simplify changing parameters.
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303 unsigned int scale_num, scale_denom; /* fraction by which to scale image */
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305 JDIMENSION jpeg_width; /* scaled JPEG image width */
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306 JDIMENSION jpeg_height; /* scaled JPEG image height */
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307 /* Dimensions of actual JPEG image that will be written to file,
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308 * derived from input dimensions by scaling factors above.
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309 * These fields are computed by jpeg_start_compress().
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310 * You can also use jpeg_calc_jpeg_dimensions() to determine these values
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311 * in advance of calling jpeg_start_compress().
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314 int data_precision; /* bits of precision in image data */
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316 int num_components; /* # of color components in JPEG image */
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317 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
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319 jpeg_component_info * comp_info;
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320 /* comp_info[i] describes component that appears i'th in SOF */
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322 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
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323 int q_scale_factor[NUM_QUANT_TBLS];
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324 /* ptrs to coefficient quantization tables, or NULL if not defined,
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325 * and corresponding scale factors (percentage, initialized 100).
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328 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
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329 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
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330 /* ptrs to Huffman coding tables, or NULL if not defined */
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332 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
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333 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
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334 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
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336 int num_scans; /* # of entries in scan_info array */
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337 const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */
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338 /* The default value of scan_info is NULL, which causes a single-scan
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339 * sequential JPEG file to be emitted. To create a multi-scan file,
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340 * set num_scans and scan_info to point to an array of scan definitions.
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343 boolean raw_data_in; /* TRUE=caller supplies downsampled data */
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344 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */
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345 boolean optimize_coding; /* TRUE=optimize entropy encoding parms */
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346 boolean CCIR601_sampling; /* TRUE=first samples are cosited */
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347 boolean do_fancy_downsampling; /* TRUE=apply fancy downsampling */
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348 int smoothing_factor; /* 1..100, or 0 for no input smoothing */
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349 J_DCT_METHOD dct_method; /* DCT algorithm selector */
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351 /* The restart interval can be specified in absolute MCUs by setting
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352 * restart_interval, or in MCU rows by setting restart_in_rows
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353 * (in which case the correct restart_interval will be figured
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356 unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */
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357 int restart_in_rows; /* if > 0, MCU rows per restart interval */
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359 /* Parameters controlling emission of special markers. */
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361 boolean write_JFIF_header; /* should a JFIF marker be written? */
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362 UINT8 JFIF_major_version; /* What to write for the JFIF version number */
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363 UINT8 JFIF_minor_version;
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364 /* These three values are not used by the JPEG code, merely copied */
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365 /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */
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366 /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */
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367 /* ratio is defined by X_density/Y_density even when density_unit=0. */
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368 UINT8 density_unit; /* JFIF code for pixel size units */
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369 UINT16 X_density; /* Horizontal pixel density */
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370 UINT16 Y_density; /* Vertical pixel density */
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371 boolean write_Adobe_marker; /* should an Adobe marker be written? */
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373 /* State variable: index of next scanline to be written to
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374 * jpeg_write_scanlines(). Application may use this to control its
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375 * processing loop, e.g., "while (next_scanline < image_height)".
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378 JDIMENSION next_scanline; /* 0 .. image_height-1 */
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380 /* Remaining fields are known throughout compressor, but generally
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381 * should not be touched by a surrounding application.
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385 * These fields are computed during compression startup
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387 boolean progressive_mode; /* TRUE if scan script uses progressive mode */
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388 int max_h_samp_factor; /* largest h_samp_factor */
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389 int max_v_samp_factor; /* largest v_samp_factor */
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391 int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */
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392 int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */
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394 JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to coef ctlr */
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395 /* The coefficient controller receives data in units of MCU rows as defined
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396 * for fully interleaved scans (whether the JPEG file is interleaved or not).
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397 * There are v_samp_factor * DCTSIZE sample rows of each component in an
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398 * "iMCU" (interleaved MCU) row.
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402 * These fields are valid during any one scan.
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403 * They describe the components and MCUs actually appearing in the scan.
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405 int comps_in_scan; /* # of JPEG components in this scan */
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406 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
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407 /* *cur_comp_info[i] describes component that appears i'th in SOS */
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409 JDIMENSION MCUs_per_row; /* # of MCUs across the image */
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410 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */
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412 int blocks_in_MCU; /* # of DCT blocks per MCU */
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413 int MCU_membership[C_MAX_BLOCKS_IN_MCU];
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414 /* MCU_membership[i] is index in cur_comp_info of component owning */
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415 /* i'th block in an MCU */
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417 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */
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419 int block_size; /* the basic DCT block size: 1..16 */
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420 const int * natural_order; /* natural-order position array */
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421 int lim_Se; /* min( Se, DCTSIZE2-1 ) */
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424 * Links to compression subobjects (methods and private variables of modules)
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426 struct jpeg_comp_master * master;
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427 struct jpeg_c_main_controller * main;
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428 struct jpeg_c_prep_controller * prep;
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429 struct jpeg_c_coef_controller * coef;
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430 struct jpeg_marker_writer * marker;
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431 struct jpeg_color_converter * cconvert;
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432 struct jpeg_downsampler * downsample;
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433 struct jpeg_forward_dct * fdct;
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434 struct jpeg_entropy_encoder * entropy;
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435 jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */
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436 int script_space_size;
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440 /* Master record for a decompression instance */
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442 struct jpeg_decompress_struct {
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443 jpeg_common_fields; /* Fields shared with jpeg_compress_struct */
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445 /* Source of compressed data */
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446 struct jpeg_source_mgr * src;
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448 /* Basic description of image --- filled in by jpeg_read_header(). */
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449 /* Application may inspect these values to decide how to process image. */
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451 JDIMENSION image_width; /* nominal image width (from SOF marker) */
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452 JDIMENSION image_height; /* nominal image height */
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453 int num_components; /* # of color components in JPEG image */
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454 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
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456 /* Decompression processing parameters --- these fields must be set before
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457 * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes
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458 * them to default values.
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461 J_COLOR_SPACE out_color_space; /* colorspace for output */
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463 unsigned int scale_num, scale_denom; /* fraction by which to scale image */
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465 double output_gamma; /* image gamma wanted in output */
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467 boolean buffered_image; /* TRUE=multiple output passes */
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468 boolean raw_data_out; /* TRUE=downsampled data wanted */
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470 J_DCT_METHOD dct_method; /* IDCT algorithm selector */
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471 boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */
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472 boolean do_block_smoothing; /* TRUE=apply interblock smoothing */
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474 boolean quantize_colors; /* TRUE=colormapped output wanted */
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475 /* the following are ignored if not quantize_colors: */
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476 J_DITHER_MODE dither_mode; /* type of color dithering to use */
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477 boolean two_pass_quantize; /* TRUE=use two-pass color quantization */
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478 int desired_number_of_colors; /* max # colors to use in created colormap */
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479 /* these are significant only in buffered-image mode: */
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480 boolean enable_1pass_quant; /* enable future use of 1-pass quantizer */
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481 boolean enable_external_quant;/* enable future use of external colormap */
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482 boolean enable_2pass_quant; /* enable future use of 2-pass quantizer */
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484 /* Description of actual output image that will be returned to application.
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485 * These fields are computed by jpeg_start_decompress().
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486 * You can also use jpeg_calc_output_dimensions() to determine these values
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487 * in advance of calling jpeg_start_decompress().
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490 JDIMENSION output_width; /* scaled image width */
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491 JDIMENSION output_height; /* scaled image height */
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492 int out_color_components; /* # of color components in out_color_space */
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493 int output_components; /* # of color components returned */
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494 /* output_components is 1 (a colormap index) when quantizing colors;
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495 * otherwise it equals out_color_components.
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497 int rec_outbuf_height; /* min recommended height of scanline buffer */
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498 /* If the buffer passed to jpeg_read_scanlines() is less than this many rows
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499 * high, space and time will be wasted due to unnecessary data copying.
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500 * Usually rec_outbuf_height will be 1 or 2, at most 4.
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503 /* When quantizing colors, the output colormap is described by these fields.
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504 * The application can supply a colormap by setting colormap non-NULL before
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505 * calling jpeg_start_decompress; otherwise a colormap is created during
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506 * jpeg_start_decompress or jpeg_start_output.
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507 * The map has out_color_components rows and actual_number_of_colors columns.
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509 int actual_number_of_colors; /* number of entries in use */
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510 JSAMPARRAY colormap; /* The color map as a 2-D pixel array */
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512 /* State variables: these variables indicate the progress of decompression.
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513 * The application may examine these but must not modify them.
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516 /* Row index of next scanline to be read from jpeg_read_scanlines().
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517 * Application may use this to control its processing loop, e.g.,
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518 * "while (output_scanline < output_height)".
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520 JDIMENSION output_scanline; /* 0 .. output_height-1 */
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522 /* Current input scan number and number of iMCU rows completed in scan.
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523 * These indicate the progress of the decompressor input side.
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525 int input_scan_number; /* Number of SOS markers seen so far */
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526 JDIMENSION input_iMCU_row; /* Number of iMCU rows completed */
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528 /* The "output scan number" is the notional scan being displayed by the
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529 * output side. The decompressor will not allow output scan/row number
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530 * to get ahead of input scan/row, but it can fall arbitrarily far behind.
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532 int output_scan_number; /* Nominal scan number being displayed */
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533 JDIMENSION output_iMCU_row; /* Number of iMCU rows read */
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535 /* Current progression status. coef_bits[c][i] indicates the precision
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536 * with which component c's DCT coefficient i (in zigzag order) is known.
\r
537 * It is -1 when no data has yet been received, otherwise it is the point
\r
538 * transform (shift) value for the most recent scan of the coefficient
\r
539 * (thus, 0 at completion of the progression).
\r
540 * This pointer is NULL when reading a non-progressive file.
\r
542 int (*coef_bits)[DCTSIZE2]; /* -1 or current Al value for each coef */
\r
544 /* Internal JPEG parameters --- the application usually need not look at
\r
545 * these fields. Note that the decompressor output side may not use
\r
546 * any parameters that can change between scans.
\r
549 /* Quantization and Huffman tables are carried forward across input
\r
550 * datastreams when processing abbreviated JPEG datastreams.
\r
553 JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
\r
554 /* ptrs to coefficient quantization tables, or NULL if not defined */
\r
556 JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
\r
557 JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
\r
558 /* ptrs to Huffman coding tables, or NULL if not defined */
\r
560 /* These parameters are never carried across datastreams, since they
\r
561 * are given in SOF/SOS markers or defined to be reset by SOI.
\r
564 int data_precision; /* bits of precision in image data */
\r
566 jpeg_component_info * comp_info;
\r
567 /* comp_info[i] describes component that appears i'th in SOF */
\r
569 boolean is_baseline; /* TRUE if Baseline SOF0 encountered */
\r
570 boolean progressive_mode; /* TRUE if SOFn specifies progressive mode */
\r
571 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */
\r
573 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
\r
574 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
\r
575 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
\r
577 unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */
\r
579 /* These fields record data obtained from optional markers recognized by
\r
580 * the JPEG library.
\r
582 boolean saw_JFIF_marker; /* TRUE iff a JFIF APP0 marker was found */
\r
583 /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */
\r
584 UINT8 JFIF_major_version; /* JFIF version number */
\r
585 UINT8 JFIF_minor_version;
\r
586 UINT8 density_unit; /* JFIF code for pixel size units */
\r
587 UINT16 X_density; /* Horizontal pixel density */
\r
588 UINT16 Y_density; /* Vertical pixel density */
\r
589 boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */
\r
590 UINT8 Adobe_transform; /* Color transform code from Adobe marker */
\r
592 boolean CCIR601_sampling; /* TRUE=first samples are cosited */
\r
594 /* Aside from the specific data retained from APPn markers known to the
\r
595 * library, the uninterpreted contents of any or all APPn and COM markers
\r
596 * can be saved in a list for examination by the application.
\r
598 jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */
\r
600 /* Remaining fields are known throughout decompressor, but generally
\r
601 * should not be touched by a surrounding application.
\r
605 * These fields are computed during decompression startup
\r
607 int max_h_samp_factor; /* largest h_samp_factor */
\r
608 int max_v_samp_factor; /* largest v_samp_factor */
\r
610 int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */
\r
611 int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */
\r
613 JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */
\r
614 /* The coefficient controller's input and output progress is measured in
\r
615 * units of "iMCU" (interleaved MCU) rows. These are the same as MCU rows
\r
616 * in fully interleaved JPEG scans, but are used whether the scan is
\r
617 * interleaved or not. We define an iMCU row as v_samp_factor DCT block
\r
618 * rows of each component. Therefore, the IDCT output contains
\r
619 * v_samp_factor*DCT_v_scaled_size sample rows of a component per iMCU row.
\r
622 JSAMPLE * sample_range_limit; /* table for fast range-limiting */
\r
625 * These fields are valid during any one scan.
\r
626 * They describe the components and MCUs actually appearing in the scan.
\r
627 * Note that the decompressor output side must not use these fields.
\r
629 int comps_in_scan; /* # of JPEG components in this scan */
\r
630 jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
\r
631 /* *cur_comp_info[i] describes component that appears i'th in SOS */
\r
633 JDIMENSION MCUs_per_row; /* # of MCUs across the image */
\r
634 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */
\r
636 int blocks_in_MCU; /* # of DCT blocks per MCU */
\r
637 int MCU_membership[D_MAX_BLOCKS_IN_MCU];
\r
638 /* MCU_membership[i] is index in cur_comp_info of component owning */
\r
639 /* i'th block in an MCU */
\r
641 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */
\r
643 /* These fields are derived from Se of first SOS marker.
\r
645 int block_size; /* the basic DCT block size: 1..16 */
\r
646 const int * natural_order; /* natural-order position array for entropy decode */
\r
647 int lim_Se; /* min( Se, DCTSIZE2-1 ) for entropy decode */
\r
649 /* This field is shared between entropy decoder and marker parser.
\r
650 * It is either zero or the code of a JPEG marker that has been
\r
651 * read from the data source, but has not yet been processed.
\r
656 * Links to decompression subobjects (methods, private variables of modules)
\r
658 struct jpeg_decomp_master * master;
\r
659 struct jpeg_d_main_controller * main;
\r
660 struct jpeg_d_coef_controller * coef;
\r
661 struct jpeg_d_post_controller * post;
\r
662 struct jpeg_input_controller * inputctl;
\r
663 struct jpeg_marker_reader * marker;
\r
664 struct jpeg_entropy_decoder * entropy;
\r
665 struct jpeg_inverse_dct * idct;
\r
666 struct jpeg_upsampler * upsample;
\r
667 struct jpeg_color_deconverter * cconvert;
\r
668 struct jpeg_color_quantizer * cquantize;
\r
672 /* "Object" declarations for JPEG modules that may be supplied or called
\r
673 * directly by the surrounding application.
\r
674 * As with all objects in the JPEG library, these structs only define the
\r
675 * publicly visible methods and state variables of a module. Additional
\r
676 * private fields may exist after the public ones.
\r
680 /* Error handler object */
\r
682 struct jpeg_error_mgr {
\r
683 /* Error exit handler: does not return to caller */
\r
684 JMETHOD(void, error_exit, (j_common_ptr cinfo));
\r
685 /* Conditionally emit a trace or warning message */
\r
686 JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level));
\r
687 /* Routine that actually outputs a trace or error message */
\r
688 JMETHOD(void, output_message, (j_common_ptr cinfo));
\r
689 /* Format a message string for the most recent JPEG error or message */
\r
690 JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer));
\r
691 #define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */
\r
692 /* Reset error state variables at start of a new image */
\r
693 JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo));
\r
695 /* The message ID code and any parameters are saved here.
\r
696 * A message can have one string parameter or up to 8 int parameters.
\r
699 #define JMSG_STR_PARM_MAX 80
\r
702 char s[JMSG_STR_PARM_MAX];
\r
705 /* Standard state variables for error facility */
\r
707 int trace_level; /* max msg_level that will be displayed */
\r
709 /* For recoverable corrupt-data errors, we emit a warning message,
\r
710 * but keep going unless emit_message chooses to abort. emit_message
\r
711 * should count warnings in num_warnings. The surrounding application
\r
712 * can check for bad data by seeing if num_warnings is nonzero at the
\r
713 * end of processing.
\r
715 long num_warnings; /* number of corrupt-data warnings */
\r
717 /* These fields point to the table(s) of error message strings.
\r
718 * An application can change the table pointer to switch to a different
\r
719 * message list (typically, to change the language in which errors are
\r
720 * reported). Some applications may wish to add additional error codes
\r
721 * that will be handled by the JPEG library error mechanism; the second
\r
722 * table pointer is used for this purpose.
\r
724 * First table includes all errors generated by JPEG library itself.
\r
725 * Error code 0 is reserved for a "no such error string" message.
\r
727 const char * const * jpeg_message_table; /* Library errors */
\r
728 int last_jpeg_message; /* Table contains strings 0..last_jpeg_message */
\r
729 /* Second table can be added by application (see cjpeg/djpeg for example).
\r
730 * It contains strings numbered first_addon_message..last_addon_message.
\r
732 const char * const * addon_message_table; /* Non-library errors */
\r
733 int first_addon_message; /* code for first string in addon table */
\r
734 int last_addon_message; /* code for last string in addon table */
\r
738 /* Progress monitor object */
\r
740 struct jpeg_progress_mgr {
\r
741 JMETHOD(void, progress_monitor, (j_common_ptr cinfo));
\r
743 long pass_counter; /* work units completed in this pass */
\r
744 long pass_limit; /* total number of work units in this pass */
\r
745 int completed_passes; /* passes completed so far */
\r
746 int total_passes; /* total number of passes expected */
\r
750 /* Data destination object for compression */
\r
752 struct jpeg_destination_mgr {
\r
753 JOCTET * next_output_byte; /* => next byte to write in buffer */
\r
754 size_t free_in_buffer; /* # of byte spaces remaining in buffer */
\r
756 JMETHOD(void, init_destination, (j_compress_ptr cinfo));
\r
757 JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo));
\r
758 JMETHOD(void, term_destination, (j_compress_ptr cinfo));
\r
762 /* Data source object for decompression */
\r
764 struct jpeg_source_mgr {
\r
765 const JOCTET * next_input_byte; /* => next byte to read from buffer */
\r
766 size_t bytes_in_buffer; /* # of bytes remaining in buffer */
\r
768 JMETHOD(void, init_source, (j_decompress_ptr cinfo));
\r
769 JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo));
\r
770 JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes));
\r
771 JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired));
\r
772 JMETHOD(void, term_source, (j_decompress_ptr cinfo));
\r
776 /* Memory manager object.
\r
777 * Allocates "small" objects (a few K total), "large" objects (tens of K),
\r
778 * and "really big" objects (virtual arrays with backing store if needed).
\r
779 * The memory manager does not allow individual objects to be freed; rather,
\r
780 * each created object is assigned to a pool, and whole pools can be freed
\r
781 * at once. This is faster and more convenient than remembering exactly what
\r
782 * to free, especially where malloc()/free() are not too speedy.
\r
783 * NB: alloc routines never return NULL. They exit to error_exit if not
\r
787 #define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */
\r
788 #define JPOOL_IMAGE 1 /* lasts until done with image/datastream */
\r
789 #define JPOOL_NUMPOOLS 2
\r
791 typedef struct jvirt_sarray_control * jvirt_sarray_ptr;
\r
792 typedef struct jvirt_barray_control * jvirt_barray_ptr;
\r
795 struct jpeg_memory_mgr {
\r
796 /* Method pointers */
\r
797 JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id,
\r
798 size_t sizeofobject));
\r
799 JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id,
\r
800 size_t sizeofobject));
\r
801 JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id,
\r
802 JDIMENSION samplesperrow,
\r
803 JDIMENSION numrows));
\r
804 JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id,
\r
805 JDIMENSION blocksperrow,
\r
806 JDIMENSION numrows));
\r
807 JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo,
\r
810 JDIMENSION samplesperrow,
\r
811 JDIMENSION numrows,
\r
812 JDIMENSION maxaccess));
\r
813 JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo,
\r
816 JDIMENSION blocksperrow,
\r
817 JDIMENSION numrows,
\r
818 JDIMENSION maxaccess));
\r
819 JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo));
\r
820 JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo,
\r
821 jvirt_sarray_ptr ptr,
\r
822 JDIMENSION start_row,
\r
823 JDIMENSION num_rows,
\r
824 boolean writable));
\r
825 JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo,
\r
826 jvirt_barray_ptr ptr,
\r
827 JDIMENSION start_row,
\r
828 JDIMENSION num_rows,
\r
829 boolean writable));
\r
830 JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id));
\r
831 JMETHOD(void, self_destruct, (j_common_ptr cinfo));
\r
833 /* Limit on memory allocation for this JPEG object. (Note that this is
\r
834 * merely advisory, not a guaranteed maximum; it only affects the space
\r
835 * used for virtual-array buffers.) May be changed by outer application
\r
836 * after creating the JPEG object.
\r
838 long max_memory_to_use;
\r
840 /* Maximum allocation request accepted by alloc_large. */
\r
841 long max_alloc_chunk;
\r
845 /* Routine signature for application-supplied marker processing methods.
\r
846 * Need not pass marker code since it is stored in cinfo->unread_marker.
\r
848 typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo));
\r
851 /* Declarations for routines called by application.
\r
852 * The JPP macro hides prototype parameters from compilers that can't cope.
\r
853 * Note JPP requires double parentheses.
\r
856 #ifdef HAVE_PROTOTYPES
\r
857 #define JPP(arglist) arglist
\r
859 #define JPP(arglist) ()
\r
863 /* Short forms of external names for systems with brain-damaged linkers.
\r
864 * We shorten external names to be unique in the first six letters, which
\r
865 * is good enough for all known systems.
\r
866 * (If your compiler itself needs names to be unique in less than 15
\r
867 * characters, you are out of luck. Get a better compiler.)
\r
870 #ifdef NEED_SHORT_EXTERNAL_NAMES
\r
871 #define jpeg_std_error jStdError
\r
872 #define jpeg_CreateCompress jCreaCompress
\r
873 #define jpeg_CreateDecompress jCreaDecompress
\r
874 #define jpeg_destroy_compress jDestCompress
\r
875 #define jpeg_destroy_decompress jDestDecompress
\r
876 #define jpeg_stdio_dest jStdDest
\r
877 #define jpeg_stdio_src jStdSrc
\r
878 #define jpeg_mem_dest jMemDest
\r
879 #define jpeg_mem_src jMemSrc
\r
880 #define jpeg_set_defaults jSetDefaults
\r
881 #define jpeg_set_colorspace jSetColorspace
\r
882 #define jpeg_default_colorspace jDefColorspace
\r
883 #define jpeg_set_quality jSetQuality
\r
884 #define jpeg_set_linear_quality jSetLQuality
\r
885 #define jpeg_default_qtables jDefQTables
\r
886 #define jpeg_add_quant_table jAddQuantTable
\r
887 #define jpeg_quality_scaling jQualityScaling
\r
888 #define jpeg_simple_progression jSimProgress
\r
889 #define jpeg_suppress_tables jSuppressTables
\r
890 #define jpeg_alloc_quant_table jAlcQTable
\r
891 #define jpeg_alloc_huff_table jAlcHTable
\r
892 #define jpeg_start_compress jStrtCompress
\r
893 #define jpeg_write_scanlines jWrtScanlines
\r
894 #define jpeg_finish_compress jFinCompress
\r
895 #define jpeg_calc_jpeg_dimensions jCjpegDimensions
\r
896 #define jpeg_write_raw_data jWrtRawData
\r
897 #define jpeg_write_marker jWrtMarker
\r
898 #define jpeg_write_m_header jWrtMHeader
\r
899 #define jpeg_write_m_byte jWrtMByte
\r
900 #define jpeg_write_tables jWrtTables
\r
901 #define jpeg_read_header jReadHeader
\r
902 #define jpeg_start_decompress jStrtDecompress
\r
903 #define jpeg_read_scanlines jReadScanlines
\r
904 #define jpeg_finish_decompress jFinDecompress
\r
905 #define jpeg_read_raw_data jReadRawData
\r
906 #define jpeg_has_multiple_scans jHasMultScn
\r
907 #define jpeg_start_output jStrtOutput
\r
908 #define jpeg_finish_output jFinOutput
\r
909 #define jpeg_input_complete jInComplete
\r
910 #define jpeg_new_colormap jNewCMap
\r
911 #define jpeg_consume_input jConsumeInput
\r
912 #define jpeg_core_output_dimensions jCoreDimensions
\r
913 #define jpeg_calc_output_dimensions jCalcDimensions
\r
914 #define jpeg_save_markers jSaveMarkers
\r
915 #define jpeg_set_marker_processor jSetMarker
\r
916 #define jpeg_read_coefficients jReadCoefs
\r
917 #define jpeg_write_coefficients jWrtCoefs
\r
918 #define jpeg_copy_critical_parameters jCopyCrit
\r
919 #define jpeg_abort_compress jAbrtCompress
\r
920 #define jpeg_abort_decompress jAbrtDecompress
\r
921 #define jpeg_abort jAbort
\r
922 #define jpeg_destroy jDestroy
\r
923 #define jpeg_resync_to_restart jResyncRestart
\r
924 #endif /* NEED_SHORT_EXTERNAL_NAMES */
\r
927 /* Default error-management setup */
\r
928 EXTERN(struct jpeg_error_mgr *) jpeg_std_error
\r
929 JPP((struct jpeg_error_mgr * err));
\r
931 /* Initialization of JPEG compression objects.
\r
932 * jpeg_create_compress() and jpeg_create_decompress() are the exported
\r
933 * names that applications should call. These expand to calls on
\r
934 * jpeg_CreateCompress and jpeg_CreateDecompress with additional information
\r
935 * passed for version mismatch checking.
\r
936 * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx.
\r
938 #define jpeg_create_compress(cinfo) \
\r
939 jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \
\r
940 (size_t) sizeof(struct jpeg_compress_struct))
\r
941 #define jpeg_create_decompress(cinfo) \
\r
942 jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \
\r
943 (size_t) sizeof(struct jpeg_decompress_struct))
\r
944 EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo,
\r
945 int version, size_t structsize));
\r
946 EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo,
\r
947 int version, size_t structsize));
\r
948 /* Destruction of JPEG compression objects */
\r
949 EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo));
\r
950 EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo));
\r
952 /* Standard data source and destination managers: stdio streams. */
\r
953 /* Caller is responsible for opening the file before and closing after. */
\r
954 EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile));
\r
955 EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile));
\r
957 /* Data source and destination managers: memory buffers. */
\r
958 EXTERN(void) jpeg_mem_dest JPP((j_compress_ptr cinfo,
\r
959 unsigned char ** outbuffer,
\r
960 unsigned long * outsize));
\r
961 EXTERN(void) jpeg_mem_src JPP((j_decompress_ptr cinfo,
\r
962 unsigned char * inbuffer,
\r
963 unsigned long insize));
\r
965 /* Default parameter setup for compression */
\r
966 EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo));
\r
967 /* Compression parameter setup aids */
\r
968 EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo,
\r
969 J_COLOR_SPACE colorspace));
\r
970 EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo));
\r
971 EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality,
\r
972 boolean force_baseline));
\r
973 EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo,
\r
975 boolean force_baseline));
\r
976 EXTERN(void) jpeg_default_qtables JPP((j_compress_ptr cinfo,
\r
977 boolean force_baseline));
\r
978 EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl,
\r
979 const unsigned int *basic_table,
\r
981 boolean force_baseline));
\r
982 EXTERN(int) jpeg_quality_scaling JPP((int quality));
\r
983 EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo));
\r
984 EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo,
\r
985 boolean suppress));
\r
986 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo));
\r
987 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo));
\r
989 /* Main entry points for compression */
\r
990 EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo,
\r
991 boolean write_all_tables));
\r
992 EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo,
\r
993 JSAMPARRAY scanlines,
\r
994 JDIMENSION num_lines));
\r
995 EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo));
\r
997 /* Precalculate JPEG dimensions for current compression parameters. */
\r
998 EXTERN(void) jpeg_calc_jpeg_dimensions JPP((j_compress_ptr cinfo));
\r
1000 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */
\r
1001 EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo,
\r
1003 JDIMENSION num_lines));
\r
1005 /* Write a special marker. See libjpeg.txt concerning safe usage. */
\r
1006 EXTERN(void) jpeg_write_marker
\r
1007 JPP((j_compress_ptr cinfo, int marker,
\r
1008 const JOCTET * dataptr, unsigned int datalen));
\r
1009 /* Same, but piecemeal. */
\r
1010 EXTERN(void) jpeg_write_m_header
\r
1011 JPP((j_compress_ptr cinfo, int marker, unsigned int datalen));
\r
1012 EXTERN(void) jpeg_write_m_byte
\r
1013 JPP((j_compress_ptr cinfo, int val));
\r
1015 /* Alternate compression function: just write an abbreviated table file */
\r
1016 EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo));
\r
1018 /* Decompression startup: read start of JPEG datastream to see what's there */
\r
1019 EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo,
\r
1020 boolean require_image));
\r
1021 /* Return value is one of: */
\r
1022 #define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */
\r
1023 #define JPEG_HEADER_OK 1 /* Found valid image datastream */
\r
1024 #define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */
\r
1025 /* If you pass require_image = TRUE (normal case), you need not check for
\r
1026 * a TABLES_ONLY return code; an abbreviated file will cause an error exit.
\r
1027 * JPEG_SUSPENDED is only possible if you use a data source module that can
\r
1028 * give a suspension return (the stdio source module doesn't).
\r
1031 /* Main entry points for decompression */
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1032 EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo));
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1033 EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo,
\r
1034 JSAMPARRAY scanlines,
\r
1035 JDIMENSION max_lines));
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1036 EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo));
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1038 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */
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1039 EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo,
\r
1041 JDIMENSION max_lines));
\r
1043 /* Additional entry points for buffered-image mode. */
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1044 EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo));
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1045 EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo,
\r
1046 int scan_number));
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1047 EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo));
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1048 EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo));
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1049 EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo));
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1050 EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo));
\r
1051 /* Return value is one of: */
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1052 /* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */
\r
1053 #define JPEG_REACHED_SOS 1 /* Reached start of new scan */
\r
1054 #define JPEG_REACHED_EOI 2 /* Reached end of image */
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1055 #define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */
\r
1056 #define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */
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1058 /* Precalculate output dimensions for current decompression parameters. */
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1059 EXTERN(void) jpeg_core_output_dimensions JPP((j_decompress_ptr cinfo));
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1060 EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo));
\r
1062 /* Control saving of COM and APPn markers into marker_list. */
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1063 EXTERN(void) jpeg_save_markers
\r
1064 JPP((j_decompress_ptr cinfo, int marker_code,
\r
1065 unsigned int length_limit));
\r
1067 /* Install a special processing method for COM or APPn markers. */
\r
1068 EXTERN(void) jpeg_set_marker_processor
\r
1069 JPP((j_decompress_ptr cinfo, int marker_code,
\r
1070 jpeg_marker_parser_method routine));
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1072 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */
\r
1073 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo));
\r
1074 EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo,
\r
1075 jvirt_barray_ptr * coef_arrays));
\r
1076 EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo,
\r
1077 j_compress_ptr dstinfo));
\r
1079 /* If you choose to abort compression or decompression before completing
\r
1080 * jpeg_finish_(de)compress, then you need to clean up to release memory,
\r
1081 * temporary files, etc. You can just call jpeg_destroy_(de)compress
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1082 * if you're done with the JPEG object, but if you want to clean it up and
\r
1083 * reuse it, call this:
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1085 EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo));
\r
1086 EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo));
\r
1088 /* Generic versions of jpeg_abort and jpeg_destroy that work on either
\r
1089 * flavor of JPEG object. These may be more convenient in some places.
\r
1091 EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo));
\r
1092 EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo));
\r
1094 /* Default restart-marker-resync procedure for use by data source modules */
\r
1095 EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo,
\r
1099 /* These marker codes are exported since applications and data source modules
\r
1100 * are likely to want to use them.
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1103 #define JPEG_RST0 0xD0 /* RST0 marker code */
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1104 #define JPEG_EOI 0xD9 /* EOI marker code */
\r
1105 #define JPEG_APP0 0xE0 /* APP0 marker code */
\r
1106 #define JPEG_COM 0xFE /* COM marker code */
\r
1109 /* If we have a brain-damaged compiler that emits warnings (or worse, errors)
\r
1110 * for structure definitions that are never filled in, keep it quiet by
\r
1111 * supplying dummy definitions for the various substructures.
\r
1114 #ifdef INCOMPLETE_TYPES_BROKEN
\r
1115 #ifndef JPEG_INTERNALS /* will be defined in jpegint.h */
\r
1116 struct jvirt_sarray_control { long dummy; };
\r
1117 struct jvirt_barray_control { long dummy; };
\r
1118 struct jpeg_comp_master { long dummy; };
\r
1119 struct jpeg_c_main_controller { long dummy; };
\r
1120 struct jpeg_c_prep_controller { long dummy; };
\r
1121 struct jpeg_c_coef_controller { long dummy; };
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1122 struct jpeg_marker_writer { long dummy; };
\r
1123 struct jpeg_color_converter { long dummy; };
\r
1124 struct jpeg_downsampler { long dummy; };
\r
1125 struct jpeg_forward_dct { long dummy; };
\r
1126 struct jpeg_entropy_encoder { long dummy; };
\r
1127 struct jpeg_decomp_master { long dummy; };
\r
1128 struct jpeg_d_main_controller { long dummy; };
\r
1129 struct jpeg_d_coef_controller { long dummy; };
\r
1130 struct jpeg_d_post_controller { long dummy; };
\r
1131 struct jpeg_input_controller { long dummy; };
\r
1132 struct jpeg_marker_reader { long dummy; };
\r
1133 struct jpeg_entropy_decoder { long dummy; };
\r
1134 struct jpeg_inverse_dct { long dummy; };
\r
1135 struct jpeg_upsampler { long dummy; };
\r
1136 struct jpeg_color_deconverter { long dummy; };
\r
1137 struct jpeg_color_quantizer { long dummy; };
\r
1138 #endif /* JPEG_INTERNALS */
\r
1139 #endif /* INCOMPLETE_TYPES_BROKEN */
\r
1143 * The JPEG library modules define JPEG_INTERNALS before including this file.
\r
1144 * The internal structure declarations are read only when that is true.
\r
1145 * Applications using the library should not include jpegint.h, but may wish
\r
1146 * to include jerror.h.
\r
1149 #ifdef JPEG_INTERNALS
\r
1150 #include "jpegint.h" /* fetch private declarations */
\r
1151 #include "jerror.h" /* fetch error codes too */
\r
1154 #ifdef __cplusplus
\r
1155 #ifndef DONT_USE_EXTERN_C
\r
1160 #endif /* JPEGLIB_H */
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