1 /* 2 * Small jpeg decoder library (Internal header) 3 * 4 * Copyright (c) 2006, Luc Saillard <luc (at) saillard.org> 5 * All rights reserved. 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are met: 8 * 9 * - Redistributions of source code must retain the above copyright notice, 10 * this list of conditions and the following disclaimer. 11 * 12 * - Redistributions in binary form must reproduce the above copyright notice, 13 * this list of conditions and the following disclaimer in the documentation 14 * and/or other materials provided with the distribution. 15 * 16 * - Neither the name of the author nor the names of its contributors may be 17 * used to endorse or promote products derived from this software without 18 * specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 21 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 24 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 * 32 */ 33 34 35 #ifndef __TINYJPEG_INTERNAL_H_ 36 #define __TINYJPEG_INTERNAL_H_ 37 38 #include <setjmp.h> 39 40 #define SANITY_CHECK 1 41 42 struct jdec_private; 43 44 #define HUFFMAN_BITS_SIZE 256 45 #define HUFFMAN_HASH_NBITS 9 46 #define HUFFMAN_HASH_SIZE (1UL<<HUFFMAN_HASH_NBITS) 47 #define HUFFMAN_HASH_MASK (HUFFMAN_HASH_SIZE-1) 48 49 #define HUFFMAN_TABLES 4 50 #define COMPONENTS 3 51 #define JPEG_MAX_WIDTH 4096 52 #define JPEG_MAX_HEIGHT 4096 53 54 struct huffman_table 55 { 56 /* Fast look up table, using HUFFMAN_HASH_NBITS bits we can have directly the symbol, 57 * if the symbol is <0, then we need to look into the tree table */ 58 short int lookup[HUFFMAN_HASH_SIZE]; 59 /* code size: give the number of bits of a symbol is encoded */ 60 unsigned char code_size[HUFFMAN_HASH_SIZE]; 61 /* some place to store value that is not encoded in the lookup table 62 * FIXME: Calculate if 256 value is enough to store all values 63 */ 64 uint16_t slowtable[16-HUFFMAN_HASH_NBITS][256]; 65 }; 66 67 struct component 68 { 69 unsigned int Hfactor; 70 unsigned int Vfactor; 71 float *Q_table; /* Pointer to the quantisation table to use */ 72 struct huffman_table *AC_table; 73 struct huffman_table *DC_table; 74 short int previous_DC; /* Previous DC coefficient */ 75 short int DCT[64]; /* DCT coef */ 76 #if SANITY_CHECK 77 unsigned int cid; 78 #endif 79 }; 80 81 82 typedef void (*decode_MCU_fct) (struct jdec_private *priv); 83 typedef void (*convert_colorspace_fct) (struct jdec_private *priv, int, int); 84 85 struct jdec_private 86 { 87 /* Public variables */ 88 uint8_t *components[COMPONENTS]; 89 unsigned int bytes_per_row[COMPONENTS]; 90 unsigned int width, height; /* Size of the image */ 91 unsigned int flags; 92 93 /* Private variables */ 94 const unsigned char *stream_begin, *stream_end; 95 unsigned int stream_length; 96 97 const unsigned char *stream; /* Pointer to the current stream */ 98 unsigned int reservoir, nbits_in_reservoir; 99 100 struct component component_infos[COMPONENTS]; 101 float Q_tables[COMPONENTS][64]; /* quantization tables */ 102 struct huffman_table HTDC[HUFFMAN_TABLES]; /* DC huffman tables */ 103 struct huffman_table HTAC[HUFFMAN_TABLES]; /* AC huffman tables */ 104 int default_huffman_table_initialized; 105 int restart_interval; 106 int restarts_to_go; /* MCUs left in this restart interval */ 107 int last_rst_marker_seen; /* Rst marker is incremented each time */ 108 109 /* Temp space used after the IDCT to store each components */ 110 uint8_t Y[64*4], Cr[64], Cb[64]; 111 112 jmp_buf jump_state; 113 /* Internal Pointer use for colorspace conversion, do not modify it !!! */ 114 uint8_t *plane[COMPONENTS]; 115 116 }; 117 118 #define IDCT tinyjpeg_idct_float 119 void tinyjpeg_idct_float (struct component *compptr, uint8_t *output_buf, int stride); 120 121 struct tinyjpeg_colorspace { 122 convert_colorspace_fct convert_colorspace[4]; 123 const decode_MCU_fct *decode_mcu_table; 124 int (*initialize)(struct jdec_private *, unsigned int *, unsigned int *); 125 }; 126 127 void tinyjpeg_process_Huffman_data_unit(struct jdec_private *priv, int component); 128 129 extern const decode_MCU_fct tinyjpeg_decode_mcu_3comp_table[4]; 130 extern const decode_MCU_fct tinyjpeg_decode_mcu_1comp_table[4]; 131 132 enum std_markers { 133 DQT = 0xDB, /* Define Quantization Table */ 134 SOF = 0xC0, /* Start of Frame (size information) */ 135 DHT = 0xC4, /* Huffman Table */ 136 SOI = 0xD8, /* Start of Image */ 137 SOS = 0xDA, /* Start of Scan */ 138 RST = 0xD0, /* Reset Marker d0 -> .. */ 139 RST7 = 0xD7, /* Reset Marker .. -> d7 */ 140 EOI = 0xD9, /* End of Image */ 141 DRI = 0xDD, /* Define Restart Interval */ 142 APP0 = 0xE0, 143 }; 144 145 #define cY 0 146 #define cCb 1 147 #define cCr 2 148 149 #define BLACK_Y 0 150 #define BLACK_U 127 151 #define BLACK_V 127 152 153 #define SANITY_CHECK 1 154 155 #if JPEG_DEBUG 156 #define error(fmt, args...) do { \ 157 snprintf(error_string, sizeof(error_string), fmt, ## args); \ 158 return -1; \ 159 } while(0) 160 161 #define trace(fmt, args...) do { \ 162 fprintf(stderr, fmt, ## args); \ 163 fflush(stderr); \ 164 } while(0) 165 #else 166 #define error(fmt, args...) do { return -1; } while(0) 167 #define trace(fmt, args...) do { } while (0) 168 #endif 169 170 #ifndef __likely 171 # define __likely(x) (!!(x)) 172 #endif 173 #ifndef __unlikely 174 # define __unlikely(x) (!!(x)) 175 #endif 176 177 #define min(x, y) ((x) < (y) ? (x) : (y)) 178 #define max(x, y) ((x) > (y) ? (x) : (y)) 179 180 #if 0 181 static char *print_bits(unsigned int value, char *bitstr) 182 { 183 int i, j; 184 i=31; 185 while (i>0) 186 { 187 if (value & (1UL<<i)) 188 break; 189 i--; 190 } 191 j=0; 192 while (i>=0) 193 { 194 bitstr[j++] = (value & (1UL<<i))?'1':'0'; 195 i--; 196 } 197 bitstr[j] = 0; 198 return bitstr; 199 } 200 201 static void print_next_16bytes(int offset, const unsigned char *stream) 202 { 203 trace("%4.4x: %2.2x %2.2x %2.2x %2.2x %2.2x %2.2x %2.2x %2.2x %2.2x %2.2x %2.2x %2.2x %2.2x %2.2x %2.2x %2.2x\n", 204 offset, 205 stream[0], stream[1], stream[2], stream[3], 206 stream[4], stream[5], stream[6], stream[7], 207 stream[8], stream[9], stream[10], stream[11], 208 stream[12], stream[13], stream[14], stream[15]); 209 } 210 211 #endif 212 213 #endif 214
