1 | ␍␊ |
2 | /* pngstruct.h - header file for PNG reference library␍␊ |
3 | *␍␊ |
4 | * Copyright (c) 1998-2012 Glenn Randers-Pehrson␍␊ |
5 | * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)␍␊ |
6 | * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)␍␊ |
7 | *␍␊ |
8 | * Last changed in libpng 1.5.9 [February 18, 2012]␍␊ |
9 | *␍␊ |
10 | * This code is released under the libpng license.␍␊ |
11 | * For conditions of distribution and use, see the disclaimer␍␊ |
12 | * and license in png.h␍␊ |
13 | */␍␊ |
14 | ␍␊ |
15 | /* The structure that holds the information to read and write PNG files.␍␊ |
16 | * The only people who need to care about what is inside of this are the␍␊ |
17 | * people who will be modifying the library for their own special needs.␍␊ |
18 | * It should NOT be accessed directly by an application.␍␊ |
19 | */␍␊ |
20 | ␍␊ |
21 | #ifndef PNGSTRUCT_H␍␊ |
22 | #define PNGSTRUCT_H␍␊ |
23 | /* zlib.h defines the structure z_stream, an instance of which is included␍␊ |
24 | * in this structure and is required for decompressing the LZ compressed␍␊ |
25 | * data in PNG files.␍␊ |
26 | */␍␊ |
27 | #include "zlib.h"␍␊ |
28 | ␍␊ |
29 | struct png_struct_def␍␊ |
30 | {␍␊ |
31 | #ifdef PNG_SETJMP_SUPPORTED␍␊ |
32 | jmp_buf longjmp_buffer; /* used in png_error */␍␊ |
33 | png_longjmp_ptr longjmp_fn;/* setjmp non-local goto function. */␍␊ |
34 | #endif␍␊ |
35 | png_error_ptr error_fn; /* function for printing errors and aborting */␍␊ |
36 | #ifdef PNG_WARNINGS_SUPPORTED␍␊ |
37 | png_error_ptr warning_fn; /* function for printing warnings */␍␊ |
38 | #endif␍␊ |
39 | png_voidp error_ptr; /* user supplied struct for error functions */␍␊ |
40 | png_rw_ptr write_data_fn; /* function for writing output data */␍␊ |
41 | png_rw_ptr read_data_fn; /* function for reading input data */␍␊ |
42 | png_voidp io_ptr; /* ptr to application struct for I/O functions */␍␊ |
43 | ␍␊ |
44 | #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED␍␊ |
45 | png_user_transform_ptr read_user_transform_fn; /* user read transform */␍␊ |
46 | #endif␍␊ |
47 | ␍␊ |
48 | #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED␍␊ |
49 | png_user_transform_ptr write_user_transform_fn; /* user write transform */␍␊ |
50 | #endif␍␊ |
51 | ␍␊ |
52 | /* These were added in libpng-1.0.2 */␍␊ |
53 | #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED␍␊ |
54 | #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \␍␊ |
55 | defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)␍␊ |
56 | png_voidp user_transform_ptr; /* user supplied struct for user transform */␍␊ |
57 | png_byte user_transform_depth; /* bit depth of user transformed pixels */␍␊ |
58 | png_byte user_transform_channels; /* channels in user transformed pixels */␍␊ |
59 | #endif␍␊ |
60 | #endif␍␊ |
61 | ␍␊ |
62 | png_uint_32 mode; /* tells us where we are in the PNG file */␍␊ |
63 | png_uint_32 flags; /* flags indicating various things to libpng */␍␊ |
64 | png_uint_32 transformations; /* which transformations to perform */␍␊ |
65 | ␍␊ |
66 | z_stream zstream; /* pointer to decompression structure (below) */␍␊ |
67 | png_bytep zbuf; /* buffer for zlib */␍␊ |
68 | uInt zbuf_size; /* size of zbuf (typically 65536) */␍␊ |
69 | #ifdef PNG_WRITE_SUPPORTED␍␊ |
70 | ␍␊ |
71 | /* Added in 1.5.4: state to keep track of whether the zstream has been␍␊ |
72 | * initialized and if so whether it is for IDAT or some other chunk.␍␊ |
73 | */␍␊ |
74 | #define PNG_ZLIB_UNINITIALIZED 0␍␊ |
75 | #define PNG_ZLIB_FOR_IDAT 1␍␊ |
76 | #define PNG_ZLIB_FOR_TEXT 2 /* anything other than IDAT */␍␊ |
77 | #define PNG_ZLIB_USE_MASK 3 /* bottom two bits */␍␊ |
78 | #define PNG_ZLIB_IN_USE 4 /* a flag value */␍␊ |
79 | ␍␊ |
80 | png_uint_32 zlib_state; /* State of zlib initialization */␍␊ |
81 | /* End of material added at libpng 1.5.4 */␍␊ |
82 | ␍␊ |
83 | int zlib_level; /* holds zlib compression level */␍␊ |
84 | int zlib_method; /* holds zlib compression method */␍␊ |
85 | int zlib_window_bits; /* holds zlib compression window bits */␍␊ |
86 | int zlib_mem_level; /* holds zlib compression memory level */␍␊ |
87 | int zlib_strategy; /* holds zlib compression strategy */␍␊ |
88 | #endif␍␊ |
89 | /* Added at libpng 1.5.4 */␍␊ |
90 | #if defined(PNG_WRITE_COMPRESSED_TEXT_SUPPORTED) || \␍␊ |
91 | defined(PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED)␍␊ |
92 | int zlib_text_level; /* holds zlib compression level */␍␊ |
93 | int zlib_text_method; /* holds zlib compression method */␍␊ |
94 | int zlib_text_window_bits; /* holds zlib compression window bits */␍␊ |
95 | int zlib_text_mem_level; /* holds zlib compression memory level */␍␊ |
96 | int zlib_text_strategy; /* holds zlib compression strategy */␍␊ |
97 | #endif␍␊ |
98 | /* End of material added at libpng 1.5.4 */␍␊ |
99 | ␍␊ |
100 | png_uint_32 width; /* width of image in pixels */␍␊ |
101 | png_uint_32 height; /* height of image in pixels */␍␊ |
102 | png_uint_32 num_rows; /* number of rows in current pass */␍␊ |
103 | png_uint_32 usr_width; /* width of row at start of write */␍␊ |
104 | png_size_t rowbytes; /* size of row in bytes */␍␊ |
105 | png_uint_32 iwidth; /* width of current interlaced row in pixels */␍␊ |
106 | png_uint_32 row_number; /* current row in interlace pass */␍␊ |
107 | png_uint_32 chunk_name; /* PNG_CHUNK() id of current chunk */␍␊ |
108 | png_bytep prev_row; /* buffer to save previous (unfiltered) row.␍␊ |
109 | * This is a pointer into big_prev_row␍␊ |
110 | */␍␊ |
111 | png_bytep row_buf; /* buffer to save current (unfiltered) row.␍␊ |
112 | * This is a pointer into big_row_buf␍␊ |
113 | */␍␊ |
114 | png_bytep sub_row; /* buffer to save "sub" row when filtering */␍␊ |
115 | png_bytep up_row; /* buffer to save "up" row when filtering */␍␊ |
116 | png_bytep avg_row; /* buffer to save "avg" row when filtering */␍␊ |
117 | png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */␍␊ |
118 | png_size_t info_rowbytes; /* Added in 1.5.4: cache of updated row bytes */␍␊ |
119 | ␍␊ |
120 | png_uint_32 idat_size; /* current IDAT size for read */␍␊ |
121 | png_uint_32 crc; /* current chunk CRC value */␍␊ |
122 | png_colorp palette; /* palette from the input file */␍␊ |
123 | png_uint_16 num_palette; /* number of color entries in palette */␍␊ |
124 | ␍␊ |
125 | /* Added at libpng-1.5.10 */␍␊ |
126 | #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED␍␊ |
127 | int num_palette_max; /* maximum palette index found in IDAT */␍␊ |
128 | #endif␍␊ |
129 | ␍␊ |
130 | png_uint_16 num_trans; /* number of transparency values */␍␊ |
131 | png_byte compression; /* file compression type (always 0) */␍␊ |
132 | png_byte filter; /* file filter type (always 0) */␍␊ |
133 | png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */␍␊ |
134 | png_byte pass; /* current interlace pass (0 - 6) */␍␊ |
135 | png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */␍␊ |
136 | png_byte color_type; /* color type of file */␍␊ |
137 | png_byte bit_depth; /* bit depth of file */␍␊ |
138 | png_byte usr_bit_depth; /* bit depth of users row: write only */␍␊ |
139 | png_byte pixel_depth; /* number of bits per pixel */␍␊ |
140 | png_byte channels; /* number of channels in file */␍␊ |
141 | png_byte usr_channels; /* channels at start of write: write only */␍␊ |
142 | png_byte sig_bytes; /* magic bytes read/written from start of file */␍␊ |
143 | png_byte maximum_pixel_depth;␍␊ |
144 | /* pixel depth used for the row buffers */␍␊ |
145 | png_byte transformed_pixel_depth;␍␊ |
146 | /* pixel depth after read/write transforms */␍␊ |
147 | png_byte io_chunk_string[5];␍␊ |
148 | /* string name of chunk */␍␊ |
149 | ␍␊ |
150 | #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)␍␊ |
151 | png_uint_16 filler; /* filler bytes for pixel expansion */␍␊ |
152 | #endif␍␊ |
153 | ␍␊ |
154 | #if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) ||\␍␊ |
155 | defined(PNG_READ_ALPHA_MODE_SUPPORTED)␍␊ |
156 | png_byte background_gamma_type;␍␊ |
157 | png_fixed_point background_gamma;␍␊ |
158 | png_color_16 background; /* background color in screen gamma space */␍␊ |
159 | #ifdef PNG_READ_GAMMA_SUPPORTED␍␊ |
160 | png_color_16 background_1; /* background normalized to gamma 1.0 */␍␊ |
161 | #endif␍␊ |
162 | #endif /* PNG_bKGD_SUPPORTED */␍␊ |
163 | ␍␊ |
164 | #ifdef PNG_WRITE_FLUSH_SUPPORTED␍␊ |
165 | png_flush_ptr output_flush_fn; /* Function for flushing output */␍␊ |
166 | png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */␍␊ |
167 | png_uint_32 flush_rows; /* number of rows written since last flush */␍␊ |
168 | #endif␍␊ |
169 | ␍␊ |
170 | #ifdef PNG_READ_GAMMA_SUPPORTED␍␊ |
171 | int gamma_shift; /* number of "insignificant" bits in 16-bit gamma */␍␊ |
172 | png_fixed_point gamma; /* file gamma value */␍␊ |
173 | png_fixed_point screen_gamma; /* screen gamma value (display_exponent) */␍␊ |
174 | ␍␊ |
175 | png_bytep gamma_table; /* gamma table for 8-bit depth files */␍␊ |
176 | png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */␍␊ |
177 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) || \␍␊ |
178 | defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \␍␊ |
179 | defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)␍␊ |
180 | png_bytep gamma_from_1; /* converts from 1.0 to screen */␍␊ |
181 | png_bytep gamma_to_1; /* converts from file to 1.0 */␍␊ |
182 | png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */␍␊ |
183 | png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */␍␊ |
184 | #endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */␍␊ |
185 | #endif␍␊ |
186 | ␍␊ |
187 | #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)␍␊ |
188 | png_color_8 sig_bit; /* significant bits in each available channel */␍␊ |
189 | #endif␍␊ |
190 | ␍␊ |
191 | #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)␍␊ |
192 | png_color_8 shift; /* shift for significant bit tranformation */␍␊ |
193 | #endif␍␊ |
194 | ␍␊ |
195 | #if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \␍␊ |
196 | || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)␍␊ |
197 | png_bytep trans_alpha; /* alpha values for paletted files */␍␊ |
198 | png_color_16 trans_color; /* transparent color for non-paletted files */␍␊ |
199 | #endif␍␊ |
200 | ␍␊ |
201 | png_read_status_ptr read_row_fn; /* called after each row is decoded */␍␊ |
202 | png_write_status_ptr write_row_fn; /* called after each row is encoded */␍␊ |
203 | #ifdef PNG_PROGRESSIVE_READ_SUPPORTED␍␊ |
204 | png_progressive_info_ptr info_fn; /* called after header data fully read */␍␊ |
205 | png_progressive_row_ptr row_fn; /* called after a prog. row is decoded */␍␊ |
206 | png_progressive_end_ptr end_fn; /* called after image is complete */␍␊ |
207 | png_bytep save_buffer_ptr; /* current location in save_buffer */␍␊ |
208 | png_bytep save_buffer; /* buffer for previously read data */␍␊ |
209 | png_bytep current_buffer_ptr; /* current location in current_buffer */␍␊ |
210 | png_bytep current_buffer; /* buffer for recently used data */␍␊ |
211 | png_uint_32 push_length; /* size of current input chunk */␍␊ |
212 | png_uint_32 skip_length; /* bytes to skip in input data */␍␊ |
213 | png_size_t save_buffer_size; /* amount of data now in save_buffer */␍␊ |
214 | png_size_t save_buffer_max; /* total size of save_buffer */␍␊ |
215 | png_size_t buffer_size; /* total amount of available input data */␍␊ |
216 | png_size_t current_buffer_size; /* amount of data now in current_buffer */␍␊ |
217 | int process_mode; /* what push library is currently doing */␍␊ |
218 | int cur_palette; /* current push library palette index */␍␊ |
219 | ␍␊ |
220 | #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */␍␊ |
221 | ␍␊ |
222 | #if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)␍␊ |
223 | /* For the Borland special 64K segment handler */␍␊ |
224 | png_bytepp offset_table_ptr;␍␊ |
225 | png_bytep offset_table;␍␊ |
226 | png_uint_16 offset_table_number;␍␊ |
227 | png_uint_16 offset_table_count;␍␊ |
228 | png_uint_16 offset_table_count_free;␍␊ |
229 | #endif␍␊ |
230 | ␍␊ |
231 | #ifdef PNG_READ_QUANTIZE_SUPPORTED␍␊ |
232 | png_bytep palette_lookup; /* lookup table for quantizing */␍␊ |
233 | png_bytep quantize_index; /* index translation for palette files */␍␊ |
234 | #endif␍␊ |
235 | ␍␊ |
236 | #if defined(PNG_READ_QUANTIZE_SUPPORTED) || defined(PNG_hIST_SUPPORTED)␍␊ |
237 | png_uint_16p hist; /* histogram */␍␊ |
238 | #endif␍␊ |
239 | ␍␊ |
240 | #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED␍␊ |
241 | png_byte heuristic_method; /* heuristic for row filter selection */␍␊ |
242 | png_byte num_prev_filters; /* number of weights for previous rows */␍␊ |
243 | png_bytep prev_filters; /* filter type(s) of previous row(s) */␍␊ |
244 | png_uint_16p filter_weights; /* weight(s) for previous line(s) */␍␊ |
245 | png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */␍␊ |
246 | png_uint_16p filter_costs; /* relative filter calculation cost */␍␊ |
247 | png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */␍␊ |
248 | #endif␍␊ |
249 | ␍␊ |
250 | #ifdef PNG_TIME_RFC1123_SUPPORTED␍␊ |
251 | /* This is going to be unused in libpng16 and removed from libpng17 */␍␊ |
252 | char time_buffer[29]; /* String to hold RFC 1123 time text */␍␊ |
253 | #endif␍␊ |
254 | ␍␊ |
255 | /* New members added in libpng-1.0.6 */␍␊ |
256 | ␍␊ |
257 | png_uint_32 free_me; /* flags items libpng is responsible for freeing */␍␊ |
258 | ␍␊ |
259 | #ifdef PNG_USER_CHUNKS_SUPPORTED␍␊ |
260 | png_voidp user_chunk_ptr;␍␊ |
261 | png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */␍␊ |
262 | #endif␍␊ |
263 | ␍␊ |
264 | #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED␍␊ |
265 | int num_chunk_list;␍␊ |
266 | png_bytep chunk_list;␍␊ |
267 | #endif␍␊ |
268 | ␍␊ |
269 | #ifdef PNG_READ_sRGB_SUPPORTED␍␊ |
270 | /* Added in 1.5.5 to record an sRGB chunk in the png. */␍␊ |
271 | png_byte is_sRGB;␍␊ |
272 | #endif␍␊ |
273 | ␍␊ |
274 | /* New members added in libpng-1.0.3 */␍␊ |
275 | #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED␍␊ |
276 | png_byte rgb_to_gray_status;␍␊ |
277 | /* Added in libpng 1.5.5 to record setting of coefficients: */␍␊ |
278 | png_byte rgb_to_gray_coefficients_set;␍␊ |
279 | /* These were changed from png_byte in libpng-1.0.6 */␍␊ |
280 | png_uint_16 rgb_to_gray_red_coeff;␍␊ |
281 | png_uint_16 rgb_to_gray_green_coeff;␍␊ |
282 | /* deleted in 1.5.5: rgb_to_gray_blue_coeff; */␍␊ |
283 | #endif␍␊ |
284 | ␍␊ |
285 | /* New member added in libpng-1.0.4 (renamed in 1.0.9) */␍␊ |
286 | #if defined(PNG_MNG_FEATURES_SUPPORTED)␍␊ |
287 | /* Changed from png_byte to png_uint_32 at version 1.2.0 */␍␊ |
288 | png_uint_32 mng_features_permitted;␍␊ |
289 | #endif␍␊ |
290 | ␍␊ |
291 | /* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */␍␊ |
292 | #ifdef PNG_MNG_FEATURES_SUPPORTED␍␊ |
293 | png_byte filter_type;␍␊ |
294 | #endif␍␊ |
295 | ␍␊ |
296 | /* New members added in libpng-1.2.0 */␍␊ |
297 | ␍␊ |
298 | /* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */␍␊ |
299 | #ifdef PNG_USER_MEM_SUPPORTED␍␊ |
300 | png_voidp mem_ptr; /* user supplied struct for mem functions */␍␊ |
301 | png_malloc_ptr malloc_fn; /* function for allocating memory */␍␊ |
302 | png_free_ptr free_fn; /* function for freeing memory */␍␊ |
303 | #endif␍␊ |
304 | ␍␊ |
305 | /* New member added in libpng-1.0.13 and 1.2.0 */␍␊ |
306 | png_bytep big_row_buf; /* buffer to save current (unfiltered) row */␍␊ |
307 | ␍␊ |
308 | #ifdef PNG_READ_QUANTIZE_SUPPORTED␍␊ |
309 | /* The following three members were added at version 1.0.14 and 1.2.4 */␍␊ |
310 | png_bytep quantize_sort; /* working sort array */␍␊ |
311 | png_bytep index_to_palette; /* where the original index currently is␍␊ |
312 | in the palette */␍␊ |
313 | png_bytep palette_to_index; /* which original index points to this␍␊ |
314 | palette color */␍␊ |
315 | #endif␍␊ |
316 | ␍␊ |
317 | /* New members added in libpng-1.0.16 and 1.2.6 */␍␊ |
318 | png_byte compression_type;␍␊ |
319 | ␍␊ |
320 | #ifdef PNG_USER_LIMITS_SUPPORTED␍␊ |
321 | png_uint_32 user_width_max;␍␊ |
322 | png_uint_32 user_height_max;␍␊ |
323 | ␍␊ |
324 | /* Added in libpng-1.4.0: Total number of sPLT, text, and unknown␍␊ |
325 | * chunks that can be stored (0 means unlimited).␍␊ |
326 | */␍␊ |
327 | png_uint_32 user_chunk_cache_max;␍␊ |
328 | ␍␊ |
329 | /* Total memory that a zTXt, sPLT, iTXt, iCCP, or unknown chunk␍␊ |
330 | * can occupy when decompressed. 0 means unlimited.␍␊ |
331 | */␍␊ |
332 | png_alloc_size_t user_chunk_malloc_max;␍␊ |
333 | #endif␍␊ |
334 | ␍␊ |
335 | /* New member added in libpng-1.0.25 and 1.2.17 */␍␊ |
336 | #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED␍␊ |
337 | /* Storage for unknown chunk that the library doesn't recognize. */␍␊ |
338 | png_unknown_chunk unknown_chunk;␍␊ |
339 | #endif␍␊ |
340 | ␍␊ |
341 | /* New member added in libpng-1.2.26 */␍␊ |
342 | png_size_t old_big_row_buf_size;␍␊ |
343 | ␍␊ |
344 | /* New member added in libpng-1.2.30 */␍␊ |
345 | png_charp chunkdata; /* buffer for reading chunk data */␍␊ |
346 | ␍␊ |
347 | #ifdef PNG_IO_STATE_SUPPORTED␍␊ |
348 | /* New member added in libpng-1.4.0 */␍␊ |
349 | png_uint_32 io_state;␍␊ |
350 | #endif␍␊ |
351 | ␍␊ |
352 | /* New member added in libpng-1.5.6 */␍␊ |
353 | png_bytep big_prev_row;␍␊ |
354 | ␍␊ |
355 | void (*read_filter[PNG_FILTER_VALUE_LAST-1])(png_row_infop row_info,␍␊ |
356 | png_bytep row, png_const_bytep prev_row);␍␊ |
357 | };␍␊ |
358 | #endif /* PNGSTRUCT_H */␍␊ |
359 | |