Line | Count | Source (jump to first uncovered line) |
1 | | |
2 | | /* pngtrans.c - transforms the data in a row (used by both readers and writers) |
3 | | * |
4 | | * Copyright (c) 2018-2024 Cosmin Truta |
5 | | * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson |
6 | | * Copyright (c) 1996-1997 Andreas Dilger |
7 | | * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc. |
8 | | * |
9 | | * This code is released under the libpng license. |
10 | | * For conditions of distribution and use, see the disclaimer |
11 | | * and license in png.h |
12 | | */ |
13 | | |
14 | | #include "pngpriv.h" |
15 | | |
16 | | #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) |
17 | | |
18 | | #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) |
19 | | /* Turn on BGR-to-RGB mapping */ |
20 | | void PNGAPI |
21 | | png_set_bgr(png_structrp png_ptr) |
22 | 0 | { |
23 | 0 | png_debug(1, "in png_set_bgr"); |
24 | |
|
25 | 0 | if (png_ptr == NULL) |
26 | 0 | return; |
27 | | |
28 | 0 | png_ptr->transformations |= PNG_BGR; |
29 | 0 | } |
30 | | #endif |
31 | | |
32 | | #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) |
33 | | /* Turn on 16-bit byte swapping */ |
34 | | void PNGAPI |
35 | | png_set_swap(png_structrp png_ptr) |
36 | 0 | { |
37 | 0 | png_debug(1, "in png_set_swap"); |
38 | |
|
39 | 0 | if (png_ptr == NULL) |
40 | 0 | return; |
41 | | |
42 | 0 | if (png_ptr->bit_depth == 16) |
43 | 0 | png_ptr->transformations |= PNG_SWAP_BYTES; |
44 | 0 | } |
45 | | #endif |
46 | | |
47 | | #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED) |
48 | | /* Turn on pixel packing */ |
49 | | void PNGAPI |
50 | | png_set_packing(png_structrp png_ptr) |
51 | 0 | { |
52 | 0 | png_debug(1, "in png_set_packing"); |
53 | |
|
54 | 0 | if (png_ptr == NULL) |
55 | 0 | return; |
56 | | |
57 | 0 | if (png_ptr->bit_depth < 8) |
58 | 0 | { |
59 | 0 | png_ptr->transformations |= PNG_PACK; |
60 | 0 | # ifdef PNG_WRITE_SUPPORTED |
61 | 0 | png_ptr->usr_bit_depth = 8; |
62 | 0 | # endif |
63 | 0 | } |
64 | 0 | } |
65 | | #endif |
66 | | |
67 | | #if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED) |
68 | | /* Turn on packed pixel swapping */ |
69 | | void PNGAPI |
70 | | png_set_packswap(png_structrp png_ptr) |
71 | 0 | { |
72 | 0 | png_debug(1, "in png_set_packswap"); |
73 | |
|
74 | 0 | if (png_ptr == NULL) |
75 | 0 | return; |
76 | | |
77 | 0 | if (png_ptr->bit_depth < 8) |
78 | 0 | png_ptr->transformations |= PNG_PACKSWAP; |
79 | 0 | } |
80 | | #endif |
81 | | |
82 | | #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) |
83 | | void PNGAPI |
84 | | png_set_shift(png_structrp png_ptr, png_const_color_8p true_bits) |
85 | 0 | { |
86 | 0 | png_debug(1, "in png_set_shift"); |
87 | |
|
88 | 0 | if (png_ptr == NULL) |
89 | 0 | return; |
90 | | |
91 | 0 | png_ptr->transformations |= PNG_SHIFT; |
92 | 0 | png_ptr->shift = *true_bits; |
93 | 0 | } |
94 | | #endif |
95 | | |
96 | | #if defined(PNG_READ_INTERLACING_SUPPORTED) || \ |
97 | | defined(PNG_WRITE_INTERLACING_SUPPORTED) |
98 | | int PNGAPI |
99 | | png_set_interlace_handling(png_structrp png_ptr) |
100 | 0 | { |
101 | 0 | png_debug(1, "in png_set_interlace handling"); |
102 | |
|
103 | 0 | if (png_ptr != 0 && png_ptr->interlaced != 0) |
104 | 0 | { |
105 | 0 | png_ptr->transformations |= PNG_INTERLACE; |
106 | 0 | return 7; |
107 | 0 | } |
108 | | |
109 | 0 | return 1; |
110 | 0 | } |
111 | | #endif |
112 | | |
113 | | #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) |
114 | | /* Add a filler byte on read, or remove a filler or alpha byte on write. |
115 | | * The filler type has changed in v0.95 to allow future 2-byte fillers |
116 | | * for 48-bit input data, as well as to avoid problems with some compilers |
117 | | * that don't like bytes as parameters. |
118 | | */ |
119 | | void PNGAPI |
120 | | png_set_filler(png_structrp png_ptr, png_uint_32 filler, int filler_loc) |
121 | 0 | { |
122 | 0 | png_debug(1, "in png_set_filler"); |
123 | |
|
124 | 0 | if (png_ptr == NULL) |
125 | 0 | return; |
126 | | |
127 | | /* In libpng 1.6 it is possible to determine whether this is a read or write |
128 | | * operation and therefore to do more checking here for a valid call. |
129 | | */ |
130 | 0 | if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0) |
131 | 0 | { |
132 | 0 | # ifdef PNG_READ_FILLER_SUPPORTED |
133 | | /* On read png_set_filler is always valid, regardless of the base PNG |
134 | | * format, because other transformations can give a format where the |
135 | | * filler code can execute (basically an 8 or 16-bit component RGB or G |
136 | | * format.) |
137 | | * |
138 | | * NOTE: usr_channels is not used by the read code! (This has led to |
139 | | * confusion in the past.) The filler is only used in the read code. |
140 | | */ |
141 | 0 | png_ptr->filler = (png_uint_16)filler; |
142 | | # else |
143 | | png_app_error(png_ptr, "png_set_filler not supported on read"); |
144 | | PNG_UNUSED(filler) /* not used in the write case */ |
145 | | return; |
146 | | # endif |
147 | 0 | } |
148 | | |
149 | 0 | else /* write */ |
150 | 0 | { |
151 | 0 | # ifdef PNG_WRITE_FILLER_SUPPORTED |
152 | | /* On write the usr_channels parameter must be set correctly at the |
153 | | * start to record the number of channels in the app-supplied data. |
154 | | */ |
155 | 0 | switch (png_ptr->color_type) |
156 | 0 | { |
157 | 0 | case PNG_COLOR_TYPE_RGB: |
158 | 0 | png_ptr->usr_channels = 4; |
159 | 0 | break; |
160 | | |
161 | 0 | case PNG_COLOR_TYPE_GRAY: |
162 | 0 | if (png_ptr->bit_depth >= 8) |
163 | 0 | { |
164 | 0 | png_ptr->usr_channels = 2; |
165 | 0 | break; |
166 | 0 | } |
167 | | |
168 | 0 | else |
169 | 0 | { |
170 | | /* There simply isn't any code in libpng to strip out bits |
171 | | * from bytes when the components are less than a byte in |
172 | | * size! |
173 | | */ |
174 | 0 | png_app_error(png_ptr, |
175 | 0 | "png_set_filler is invalid for" |
176 | 0 | " low bit depth gray output"); |
177 | 0 | return; |
178 | 0 | } |
179 | | |
180 | 0 | default: |
181 | 0 | png_app_error(png_ptr, |
182 | 0 | "png_set_filler: inappropriate color type"); |
183 | 0 | return; |
184 | 0 | } |
185 | | # else |
186 | | png_app_error(png_ptr, "png_set_filler not supported on write"); |
187 | | return; |
188 | | # endif |
189 | 0 | } |
190 | | |
191 | | /* Here on success - libpng supports the operation, set the transformation |
192 | | * and the flag to say where the filler channel is. |
193 | | */ |
194 | 0 | png_ptr->transformations |= PNG_FILLER; |
195 | |
|
196 | 0 | if (filler_loc == PNG_FILLER_AFTER) |
197 | 0 | png_ptr->flags |= PNG_FLAG_FILLER_AFTER; |
198 | | |
199 | 0 | else |
200 | 0 | png_ptr->flags &= ~PNG_FLAG_FILLER_AFTER; |
201 | 0 | } |
202 | | |
203 | | /* Added to libpng-1.2.7 */ |
204 | | void PNGAPI |
205 | | png_set_add_alpha(png_structrp png_ptr, png_uint_32 filler, int filler_loc) |
206 | 0 | { |
207 | 0 | png_debug(1, "in png_set_add_alpha"); |
208 | |
|
209 | 0 | if (png_ptr == NULL) |
210 | 0 | return; |
211 | | |
212 | 0 | png_set_filler(png_ptr, filler, filler_loc); |
213 | | /* The above may fail to do anything. */ |
214 | 0 | if ((png_ptr->transformations & PNG_FILLER) != 0) |
215 | 0 | png_ptr->transformations |= PNG_ADD_ALPHA; |
216 | 0 | } |
217 | | |
218 | | #endif |
219 | | |
220 | | #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \ |
221 | | defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) |
222 | | void PNGAPI |
223 | | png_set_swap_alpha(png_structrp png_ptr) |
224 | 0 | { |
225 | 0 | png_debug(1, "in png_set_swap_alpha"); |
226 | |
|
227 | 0 | if (png_ptr == NULL) |
228 | 0 | return; |
229 | | |
230 | 0 | png_ptr->transformations |= PNG_SWAP_ALPHA; |
231 | 0 | } |
232 | | #endif |
233 | | |
234 | | #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \ |
235 | | defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) |
236 | | void PNGAPI |
237 | | png_set_invert_alpha(png_structrp png_ptr) |
238 | 0 | { |
239 | 0 | png_debug(1, "in png_set_invert_alpha"); |
240 | |
|
241 | 0 | if (png_ptr == NULL) |
242 | 0 | return; |
243 | | |
244 | 0 | png_ptr->transformations |= PNG_INVERT_ALPHA; |
245 | 0 | } |
246 | | #endif |
247 | | |
248 | | #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) |
249 | | void PNGAPI |
250 | | png_set_invert_mono(png_structrp png_ptr) |
251 | 0 | { |
252 | 0 | png_debug(1, "in png_set_invert_mono"); |
253 | |
|
254 | 0 | if (png_ptr == NULL) |
255 | 0 | return; |
256 | | |
257 | 0 | png_ptr->transformations |= PNG_INVERT_MONO; |
258 | 0 | } |
259 | | |
260 | | /* Invert monochrome grayscale data */ |
261 | | void /* PRIVATE */ |
262 | | png_do_invert(png_row_infop row_info, png_bytep row) |
263 | 0 | { |
264 | 0 | png_debug(1, "in png_do_invert"); |
265 | | |
266 | | /* This test removed from libpng version 1.0.13 and 1.2.0: |
267 | | * if (row_info->bit_depth == 1 && |
268 | | */ |
269 | 0 | if (row_info->color_type == PNG_COLOR_TYPE_GRAY) |
270 | 0 | { |
271 | 0 | png_bytep rp = row; |
272 | 0 | size_t i; |
273 | 0 | size_t istop = row_info->rowbytes; |
274 | |
|
275 | 0 | for (i = 0; i < istop; i++) |
276 | 0 | { |
277 | 0 | *rp = (png_byte)(~(*rp)); |
278 | 0 | rp++; |
279 | 0 | } |
280 | 0 | } |
281 | | |
282 | 0 | else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA && |
283 | 0 | row_info->bit_depth == 8) |
284 | 0 | { |
285 | 0 | png_bytep rp = row; |
286 | 0 | size_t i; |
287 | 0 | size_t istop = row_info->rowbytes; |
288 | |
|
289 | 0 | for (i = 0; i < istop; i += 2) |
290 | 0 | { |
291 | 0 | *rp = (png_byte)(~(*rp)); |
292 | 0 | rp += 2; |
293 | 0 | } |
294 | 0 | } |
295 | | |
296 | 0 | #ifdef PNG_16BIT_SUPPORTED |
297 | 0 | else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA && |
298 | 0 | row_info->bit_depth == 16) |
299 | 0 | { |
300 | 0 | png_bytep rp = row; |
301 | 0 | size_t i; |
302 | 0 | size_t istop = row_info->rowbytes; |
303 | |
|
304 | 0 | for (i = 0; i < istop; i += 4) |
305 | 0 | { |
306 | 0 | *rp = (png_byte)(~(*rp)); |
307 | 0 | *(rp + 1) = (png_byte)(~(*(rp + 1))); |
308 | 0 | rp += 4; |
309 | 0 | } |
310 | 0 | } |
311 | 0 | #endif |
312 | 0 | } |
313 | | #endif |
314 | | |
315 | | #ifdef PNG_16BIT_SUPPORTED |
316 | | #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) |
317 | | /* Swaps byte order on 16-bit depth images */ |
318 | | void /* PRIVATE */ |
319 | | png_do_swap(png_row_infop row_info, png_bytep row) |
320 | 0 | { |
321 | 0 | png_debug(1, "in png_do_swap"); |
322 | |
|
323 | 0 | if (row_info->bit_depth == 16) |
324 | 0 | { |
325 | 0 | png_bytep rp = row; |
326 | 0 | png_uint_32 i; |
327 | 0 | png_uint_32 istop= row_info->width * row_info->channels; |
328 | |
|
329 | 0 | for (i = 0; i < istop; i++, rp += 2) |
330 | 0 | { |
331 | | #ifdef PNG_BUILTIN_BSWAP16_SUPPORTED |
332 | | /* Feature added to libpng-1.6.11 for testing purposes, not |
333 | | * enabled by default. |
334 | | */ |
335 | | *(png_uint_16*)rp = __builtin_bswap16(*(png_uint_16*)rp); |
336 | | #else |
337 | 0 | png_byte t = *rp; |
338 | 0 | *rp = *(rp + 1); |
339 | 0 | *(rp + 1) = t; |
340 | 0 | #endif |
341 | 0 | } |
342 | 0 | } |
343 | 0 | } |
344 | | #endif |
345 | | #endif |
346 | | |
347 | | #if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED) |
348 | | static const png_byte onebppswaptable[256] = { |
349 | | 0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, |
350 | | 0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0, |
351 | | 0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8, |
352 | | 0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8, |
353 | | 0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4, |
354 | | 0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4, |
355 | | 0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC, |
356 | | 0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC, |
357 | | 0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2, |
358 | | 0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2, |
359 | | 0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA, |
360 | | 0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA, |
361 | | 0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6, |
362 | | 0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6, |
363 | | 0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE, |
364 | | 0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE, |
365 | | 0x01, 0x81, 0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1, |
366 | | 0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1, |
367 | | 0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9, |
368 | | 0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9, |
369 | | 0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5, |
370 | | 0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5, |
371 | | 0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD, 0x6D, 0xED, |
372 | | 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD, |
373 | | 0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3, |
374 | | 0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3, |
375 | | 0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB, |
376 | | 0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB, |
377 | | 0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7, |
378 | | 0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7, |
379 | | 0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF, |
380 | | 0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF |
381 | | }; |
382 | | |
383 | | static const png_byte twobppswaptable[256] = { |
384 | | 0x00, 0x40, 0x80, 0xC0, 0x10, 0x50, 0x90, 0xD0, |
385 | | 0x20, 0x60, 0xA0, 0xE0, 0x30, 0x70, 0xB0, 0xF0, |
386 | | 0x04, 0x44, 0x84, 0xC4, 0x14, 0x54, 0x94, 0xD4, |
387 | | 0x24, 0x64, 0xA4, 0xE4, 0x34, 0x74, 0xB4, 0xF4, |
388 | | 0x08, 0x48, 0x88, 0xC8, 0x18, 0x58, 0x98, 0xD8, |
389 | | 0x28, 0x68, 0xA8, 0xE8, 0x38, 0x78, 0xB8, 0xF8, |
390 | | 0x0C, 0x4C, 0x8C, 0xCC, 0x1C, 0x5C, 0x9C, 0xDC, |
391 | | 0x2C, 0x6C, 0xAC, 0xEC, 0x3C, 0x7C, 0xBC, 0xFC, |
392 | | 0x01, 0x41, 0x81, 0xC1, 0x11, 0x51, 0x91, 0xD1, |
393 | | 0x21, 0x61, 0xA1, 0xE1, 0x31, 0x71, 0xB1, 0xF1, |
394 | | 0x05, 0x45, 0x85, 0xC5, 0x15, 0x55, 0x95, 0xD5, |
395 | | 0x25, 0x65, 0xA5, 0xE5, 0x35, 0x75, 0xB5, 0xF5, |
396 | | 0x09, 0x49, 0x89, 0xC9, 0x19, 0x59, 0x99, 0xD9, |
397 | | 0x29, 0x69, 0xA9, 0xE9, 0x39, 0x79, 0xB9, 0xF9, |
398 | | 0x0D, 0x4D, 0x8D, 0xCD, 0x1D, 0x5D, 0x9D, 0xDD, |
399 | | 0x2D, 0x6D, 0xAD, 0xED, 0x3D, 0x7D, 0xBD, 0xFD, |
400 | | 0x02, 0x42, 0x82, 0xC2, 0x12, 0x52, 0x92, 0xD2, |
401 | | 0x22, 0x62, 0xA2, 0xE2, 0x32, 0x72, 0xB2, 0xF2, |
402 | | 0x06, 0x46, 0x86, 0xC6, 0x16, 0x56, 0x96, 0xD6, |
403 | | 0x26, 0x66, 0xA6, 0xE6, 0x36, 0x76, 0xB6, 0xF6, |
404 | | 0x0A, 0x4A, 0x8A, 0xCA, 0x1A, 0x5A, 0x9A, 0xDA, |
405 | | 0x2A, 0x6A, 0xAA, 0xEA, 0x3A, 0x7A, 0xBA, 0xFA, |
406 | | 0x0E, 0x4E, 0x8E, 0xCE, 0x1E, 0x5E, 0x9E, 0xDE, |
407 | | 0x2E, 0x6E, 0xAE, 0xEE, 0x3E, 0x7E, 0xBE, 0xFE, |
408 | | 0x03, 0x43, 0x83, 0xC3, 0x13, 0x53, 0x93, 0xD3, |
409 | | 0x23, 0x63, 0xA3, 0xE3, 0x33, 0x73, 0xB3, 0xF3, |
410 | | 0x07, 0x47, 0x87, 0xC7, 0x17, 0x57, 0x97, 0xD7, |
411 | | 0x27, 0x67, 0xA7, 0xE7, 0x37, 0x77, 0xB7, 0xF7, |
412 | | 0x0B, 0x4B, 0x8B, 0xCB, 0x1B, 0x5B, 0x9B, 0xDB, |
413 | | 0x2B, 0x6B, 0xAB, 0xEB, 0x3B, 0x7B, 0xBB, 0xFB, |
414 | | 0x0F, 0x4F, 0x8F, 0xCF, 0x1F, 0x5F, 0x9F, 0xDF, |
415 | | 0x2F, 0x6F, 0xAF, 0xEF, 0x3F, 0x7F, 0xBF, 0xFF |
416 | | }; |
417 | | |
418 | | static const png_byte fourbppswaptable[256] = { |
419 | | 0x00, 0x10, 0x20, 0x30, 0x40, 0x50, 0x60, 0x70, |
420 | | 0x80, 0x90, 0xA0, 0xB0, 0xC0, 0xD0, 0xE0, 0xF0, |
421 | | 0x01, 0x11, 0x21, 0x31, 0x41, 0x51, 0x61, 0x71, |
422 | | 0x81, 0x91, 0xA1, 0xB1, 0xC1, 0xD1, 0xE1, 0xF1, |
423 | | 0x02, 0x12, 0x22, 0x32, 0x42, 0x52, 0x62, 0x72, |
424 | | 0x82, 0x92, 0xA2, 0xB2, 0xC2, 0xD2, 0xE2, 0xF2, |
425 | | 0x03, 0x13, 0x23, 0x33, 0x43, 0x53, 0x63, 0x73, |
426 | | 0x83, 0x93, 0xA3, 0xB3, 0xC3, 0xD3, 0xE3, 0xF3, |
427 | | 0x04, 0x14, 0x24, 0x34, 0x44, 0x54, 0x64, 0x74, |
428 | | 0x84, 0x94, 0xA4, 0xB4, 0xC4, 0xD4, 0xE4, 0xF4, |
429 | | 0x05, 0x15, 0x25, 0x35, 0x45, 0x55, 0x65, 0x75, |
430 | | 0x85, 0x95, 0xA5, 0xB5, 0xC5, 0xD5, 0xE5, 0xF5, |
431 | | 0x06, 0x16, 0x26, 0x36, 0x46, 0x56, 0x66, 0x76, |
432 | | 0x86, 0x96, 0xA6, 0xB6, 0xC6, 0xD6, 0xE6, 0xF6, |
433 | | 0x07, 0x17, 0x27, 0x37, 0x47, 0x57, 0x67, 0x77, |
434 | | 0x87, 0x97, 0xA7, 0xB7, 0xC7, 0xD7, 0xE7, 0xF7, |
435 | | 0x08, 0x18, 0x28, 0x38, 0x48, 0x58, 0x68, 0x78, |
436 | | 0x88, 0x98, 0xA8, 0xB8, 0xC8, 0xD8, 0xE8, 0xF8, |
437 | | 0x09, 0x19, 0x29, 0x39, 0x49, 0x59, 0x69, 0x79, |
438 | | 0x89, 0x99, 0xA9, 0xB9, 0xC9, 0xD9, 0xE9, 0xF9, |
439 | | 0x0A, 0x1A, 0x2A, 0x3A, 0x4A, 0x5A, 0x6A, 0x7A, |
440 | | 0x8A, 0x9A, 0xAA, 0xBA, 0xCA, 0xDA, 0xEA, 0xFA, |
441 | | 0x0B, 0x1B, 0x2B, 0x3B, 0x4B, 0x5B, 0x6B, 0x7B, |
442 | | 0x8B, 0x9B, 0xAB, 0xBB, 0xCB, 0xDB, 0xEB, 0xFB, |
443 | | 0x0C, 0x1C, 0x2C, 0x3C, 0x4C, 0x5C, 0x6C, 0x7C, |
444 | | 0x8C, 0x9C, 0xAC, 0xBC, 0xCC, 0xDC, 0xEC, 0xFC, |
445 | | 0x0D, 0x1D, 0x2D, 0x3D, 0x4D, 0x5D, 0x6D, 0x7D, |
446 | | 0x8D, 0x9D, 0xAD, 0xBD, 0xCD, 0xDD, 0xED, 0xFD, |
447 | | 0x0E, 0x1E, 0x2E, 0x3E, 0x4E, 0x5E, 0x6E, 0x7E, |
448 | | 0x8E, 0x9E, 0xAE, 0xBE, 0xCE, 0xDE, 0xEE, 0xFE, |
449 | | 0x0F, 0x1F, 0x2F, 0x3F, 0x4F, 0x5F, 0x6F, 0x7F, |
450 | | 0x8F, 0x9F, 0xAF, 0xBF, 0xCF, 0xDF, 0xEF, 0xFF |
451 | | }; |
452 | | |
453 | | /* Swaps pixel packing order within bytes */ |
454 | | void /* PRIVATE */ |
455 | | png_do_packswap(png_row_infop row_info, png_bytep row) |
456 | 0 | { |
457 | 0 | png_debug(1, "in png_do_packswap"); |
458 | |
|
459 | 0 | if (row_info->bit_depth < 8) |
460 | 0 | { |
461 | 0 | png_bytep rp; |
462 | 0 | png_const_bytep end, table; |
463 | |
|
464 | 0 | end = row + row_info->rowbytes; |
465 | |
|
466 | 0 | if (row_info->bit_depth == 1) |
467 | 0 | table = onebppswaptable; |
468 | | |
469 | 0 | else if (row_info->bit_depth == 2) |
470 | 0 | table = twobppswaptable; |
471 | | |
472 | 0 | else if (row_info->bit_depth == 4) |
473 | 0 | table = fourbppswaptable; |
474 | | |
475 | 0 | else |
476 | 0 | return; |
477 | | |
478 | 0 | for (rp = row; rp < end; rp++) |
479 | 0 | *rp = table[*rp]; |
480 | 0 | } |
481 | 0 | } |
482 | | #endif /* PACKSWAP || WRITE_PACKSWAP */ |
483 | | |
484 | | #if defined(PNG_WRITE_FILLER_SUPPORTED) || \ |
485 | | defined(PNG_READ_STRIP_ALPHA_SUPPORTED) |
486 | | /* Remove a channel - this used to be 'png_do_strip_filler' but it used a |
487 | | * somewhat weird combination of flags to determine what to do. All the calls |
488 | | * to png_do_strip_filler are changed in 1.5.2 to call this instead with the |
489 | | * correct arguments. |
490 | | * |
491 | | * The routine isn't general - the channel must be the channel at the start or |
492 | | * end (not in the middle) of each pixel. |
493 | | */ |
494 | | void /* PRIVATE */ |
495 | | png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start) |
496 | 0 | { |
497 | 0 | png_bytep sp = row; /* source pointer */ |
498 | 0 | png_bytep dp = row; /* destination pointer */ |
499 | 0 | png_bytep ep = row + row_info->rowbytes; /* One beyond end of row */ |
500 | |
|
501 | 0 | png_debug(1, "in png_do_strip_channel"); |
502 | | |
503 | | /* At the start sp will point to the first byte to copy and dp to where |
504 | | * it is copied to. ep always points just beyond the end of the row, so |
505 | | * the loop simply copies (channels-1) channels until sp reaches ep. |
506 | | * |
507 | | * at_start: 0 -- convert AG, XG, ARGB, XRGB, AAGG, XXGG, etc. |
508 | | * nonzero -- convert GA, GX, RGBA, RGBX, GGAA, RRGGBBXX, etc. |
509 | | */ |
510 | | |
511 | | /* GA, GX, XG cases */ |
512 | 0 | if (row_info->channels == 2) |
513 | 0 | { |
514 | 0 | if (row_info->bit_depth == 8) |
515 | 0 | { |
516 | 0 | if (at_start != 0) /* Skip initial filler */ |
517 | 0 | ++sp; |
518 | 0 | else /* Skip initial channel and, for sp, the filler */ |
519 | 0 | { |
520 | 0 | sp += 2; ++dp; |
521 | 0 | } |
522 | | |
523 | | /* For a 1 pixel wide image there is nothing to do */ |
524 | 0 | while (sp < ep) |
525 | 0 | { |
526 | 0 | *dp++ = *sp; sp += 2; |
527 | 0 | } |
528 | |
|
529 | 0 | row_info->pixel_depth = 8; |
530 | 0 | } |
531 | | |
532 | 0 | else if (row_info->bit_depth == 16) |
533 | 0 | { |
534 | 0 | if (at_start != 0) /* Skip initial filler */ |
535 | 0 | sp += 2; |
536 | 0 | else /* Skip initial channel and, for sp, the filler */ |
537 | 0 | { |
538 | 0 | sp += 4; dp += 2; |
539 | 0 | } |
540 | |
|
541 | 0 | while (sp < ep) |
542 | 0 | { |
543 | 0 | *dp++ = *sp++; *dp++ = *sp; sp += 3; |
544 | 0 | } |
545 | |
|
546 | 0 | row_info->pixel_depth = 16; |
547 | 0 | } |
548 | | |
549 | 0 | else |
550 | 0 | return; /* bad bit depth */ |
551 | | |
552 | 0 | row_info->channels = 1; |
553 | | |
554 | | /* Finally fix the color type if it records an alpha channel */ |
555 | 0 | if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) |
556 | 0 | row_info->color_type = PNG_COLOR_TYPE_GRAY; |
557 | 0 | } |
558 | | |
559 | | /* RGBA, RGBX, XRGB cases */ |
560 | 0 | else if (row_info->channels == 4) |
561 | 0 | { |
562 | 0 | if (row_info->bit_depth == 8) |
563 | 0 | { |
564 | 0 | if (at_start != 0) /* Skip initial filler */ |
565 | 0 | ++sp; |
566 | 0 | else /* Skip initial channels and, for sp, the filler */ |
567 | 0 | { |
568 | 0 | sp += 4; dp += 3; |
569 | 0 | } |
570 | | |
571 | | /* Note that the loop adds 3 to dp and 4 to sp each time. */ |
572 | 0 | while (sp < ep) |
573 | 0 | { |
574 | 0 | *dp++ = *sp++; *dp++ = *sp++; *dp++ = *sp; sp += 2; |
575 | 0 | } |
576 | |
|
577 | 0 | row_info->pixel_depth = 24; |
578 | 0 | } |
579 | | |
580 | 0 | else if (row_info->bit_depth == 16) |
581 | 0 | { |
582 | 0 | if (at_start != 0) /* Skip initial filler */ |
583 | 0 | sp += 2; |
584 | 0 | else /* Skip initial channels and, for sp, the filler */ |
585 | 0 | { |
586 | 0 | sp += 8; dp += 6; |
587 | 0 | } |
588 | |
|
589 | 0 | while (sp < ep) |
590 | 0 | { |
591 | | /* Copy 6 bytes, skip 2 */ |
592 | 0 | *dp++ = *sp++; *dp++ = *sp++; |
593 | 0 | *dp++ = *sp++; *dp++ = *sp++; |
594 | 0 | *dp++ = *sp++; *dp++ = *sp; sp += 3; |
595 | 0 | } |
596 | |
|
597 | 0 | row_info->pixel_depth = 48; |
598 | 0 | } |
599 | | |
600 | 0 | else |
601 | 0 | return; /* bad bit depth */ |
602 | | |
603 | 0 | row_info->channels = 3; |
604 | | |
605 | | /* Finally fix the color type if it records an alpha channel */ |
606 | 0 | if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
607 | 0 | row_info->color_type = PNG_COLOR_TYPE_RGB; |
608 | 0 | } |
609 | | |
610 | 0 | else |
611 | 0 | return; /* The filler channel has gone already */ |
612 | | |
613 | | /* Fix the rowbytes value. */ |
614 | 0 | row_info->rowbytes = (size_t)(dp-row); |
615 | 0 | } |
616 | | #endif |
617 | | |
618 | | #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) |
619 | | /* Swaps red and blue bytes within a pixel */ |
620 | | void /* PRIVATE */ |
621 | | png_do_bgr(png_row_infop row_info, png_bytep row) |
622 | 0 | { |
623 | 0 | png_debug(1, "in png_do_bgr"); |
624 | |
|
625 | 0 | if ((row_info->color_type & PNG_COLOR_MASK_COLOR) != 0) |
626 | 0 | { |
627 | 0 | png_uint_32 row_width = row_info->width; |
628 | 0 | if (row_info->bit_depth == 8) |
629 | 0 | { |
630 | 0 | if (row_info->color_type == PNG_COLOR_TYPE_RGB) |
631 | 0 | { |
632 | 0 | png_bytep rp; |
633 | 0 | png_uint_32 i; |
634 | |
|
635 | 0 | for (i = 0, rp = row; i < row_width; i++, rp += 3) |
636 | 0 | { |
637 | 0 | png_byte save = *rp; |
638 | 0 | *rp = *(rp + 2); |
639 | 0 | *(rp + 2) = save; |
640 | 0 | } |
641 | 0 | } |
642 | | |
643 | 0 | else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
644 | 0 | { |
645 | 0 | png_bytep rp; |
646 | 0 | png_uint_32 i; |
647 | |
|
648 | 0 | for (i = 0, rp = row; i < row_width; i++, rp += 4) |
649 | 0 | { |
650 | 0 | png_byte save = *rp; |
651 | 0 | *rp = *(rp + 2); |
652 | 0 | *(rp + 2) = save; |
653 | 0 | } |
654 | 0 | } |
655 | 0 | } |
656 | | |
657 | 0 | #ifdef PNG_16BIT_SUPPORTED |
658 | 0 | else if (row_info->bit_depth == 16) |
659 | 0 | { |
660 | 0 | if (row_info->color_type == PNG_COLOR_TYPE_RGB) |
661 | 0 | { |
662 | 0 | png_bytep rp; |
663 | 0 | png_uint_32 i; |
664 | |
|
665 | 0 | for (i = 0, rp = row; i < row_width; i++, rp += 6) |
666 | 0 | { |
667 | 0 | png_byte save = *rp; |
668 | 0 | *rp = *(rp + 4); |
669 | 0 | *(rp + 4) = save; |
670 | 0 | save = *(rp + 1); |
671 | 0 | *(rp + 1) = *(rp + 5); |
672 | 0 | *(rp + 5) = save; |
673 | 0 | } |
674 | 0 | } |
675 | | |
676 | 0 | else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
677 | 0 | { |
678 | 0 | png_bytep rp; |
679 | 0 | png_uint_32 i; |
680 | |
|
681 | 0 | for (i = 0, rp = row; i < row_width; i++, rp += 8) |
682 | 0 | { |
683 | 0 | png_byte save = *rp; |
684 | 0 | *rp = *(rp + 4); |
685 | 0 | *(rp + 4) = save; |
686 | 0 | save = *(rp + 1); |
687 | 0 | *(rp + 1) = *(rp + 5); |
688 | 0 | *(rp + 5) = save; |
689 | 0 | } |
690 | 0 | } |
691 | 0 | } |
692 | 0 | #endif |
693 | 0 | } |
694 | 0 | } |
695 | | #endif /* READ_BGR || WRITE_BGR */ |
696 | | |
697 | | #if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \ |
698 | | defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED) |
699 | | /* Added at libpng-1.5.10 */ |
700 | | void /* PRIVATE */ |
701 | | png_do_check_palette_indexes(png_structrp png_ptr, png_row_infop row_info) |
702 | 0 | { |
703 | 0 | png_debug(1, "in png_do_check_palette_indexes"); |
704 | |
|
705 | 0 | if (png_ptr->num_palette < (1 << row_info->bit_depth) && |
706 | 0 | png_ptr->num_palette > 0) /* num_palette can be 0 in MNG files */ |
707 | 0 | { |
708 | | /* Calculations moved outside switch in an attempt to stop different |
709 | | * compiler warnings. 'padding' is in *bits* within the last byte, it is |
710 | | * an 'int' because pixel_depth becomes an 'int' in the expression below, |
711 | | * and this calculation is used because it avoids warnings that other |
712 | | * forms produced on either GCC or MSVC. |
713 | | */ |
714 | 0 | int padding = PNG_PADBITS(row_info->pixel_depth, row_info->width); |
715 | 0 | png_bytep rp = png_ptr->row_buf + row_info->rowbytes; |
716 | |
|
717 | 0 | switch (row_info->bit_depth) |
718 | 0 | { |
719 | 0 | case 1: |
720 | 0 | { |
721 | | /* in this case, all bytes must be 0 so we don't need |
722 | | * to unpack the pixels except for the rightmost one. |
723 | | */ |
724 | 0 | for (; rp > png_ptr->row_buf; rp--) |
725 | 0 | { |
726 | 0 | if ((*rp >> padding) != 0) |
727 | 0 | png_ptr->num_palette_max = 1; |
728 | 0 | padding = 0; |
729 | 0 | } |
730 | |
|
731 | 0 | break; |
732 | 0 | } |
733 | | |
734 | 0 | case 2: |
735 | 0 | { |
736 | 0 | for (; rp > png_ptr->row_buf; rp--) |
737 | 0 | { |
738 | 0 | int i = ((*rp >> padding) & 0x03); |
739 | |
|
740 | 0 | if (i > png_ptr->num_palette_max) |
741 | 0 | png_ptr->num_palette_max = i; |
742 | |
|
743 | 0 | i = (((*rp >> padding) >> 2) & 0x03); |
744 | |
|
745 | 0 | if (i > png_ptr->num_palette_max) |
746 | 0 | png_ptr->num_palette_max = i; |
747 | |
|
748 | 0 | i = (((*rp >> padding) >> 4) & 0x03); |
749 | |
|
750 | 0 | if (i > png_ptr->num_palette_max) |
751 | 0 | png_ptr->num_palette_max = i; |
752 | |
|
753 | 0 | i = (((*rp >> padding) >> 6) & 0x03); |
754 | |
|
755 | 0 | if (i > png_ptr->num_palette_max) |
756 | 0 | png_ptr->num_palette_max = i; |
757 | |
|
758 | 0 | padding = 0; |
759 | 0 | } |
760 | |
|
761 | 0 | break; |
762 | 0 | } |
763 | | |
764 | 0 | case 4: |
765 | 0 | { |
766 | 0 | for (; rp > png_ptr->row_buf; rp--) |
767 | 0 | { |
768 | 0 | int i = ((*rp >> padding) & 0x0f); |
769 | |
|
770 | 0 | if (i > png_ptr->num_palette_max) |
771 | 0 | png_ptr->num_palette_max = i; |
772 | |
|
773 | 0 | i = (((*rp >> padding) >> 4) & 0x0f); |
774 | |
|
775 | 0 | if (i > png_ptr->num_palette_max) |
776 | 0 | png_ptr->num_palette_max = i; |
777 | |
|
778 | 0 | padding = 0; |
779 | 0 | } |
780 | |
|
781 | 0 | break; |
782 | 0 | } |
783 | | |
784 | 0 | case 8: |
785 | 0 | { |
786 | 0 | for (; rp > png_ptr->row_buf; rp--) |
787 | 0 | { |
788 | 0 | if (*rp > png_ptr->num_palette_max) |
789 | 0 | png_ptr->num_palette_max = (int) *rp; |
790 | 0 | } |
791 | |
|
792 | 0 | break; |
793 | 0 | } |
794 | | |
795 | 0 | default: |
796 | 0 | break; |
797 | 0 | } |
798 | 0 | } |
799 | 0 | } |
800 | | #endif /* CHECK_FOR_INVALID_INDEX */ |
801 | | |
802 | | #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ |
803 | | defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) |
804 | | #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED |
805 | | void PNGAPI |
806 | | png_set_user_transform_info(png_structrp png_ptr, png_voidp |
807 | | user_transform_ptr, int user_transform_depth, int user_transform_channels) |
808 | 0 | { |
809 | 0 | png_debug(1, "in png_set_user_transform_info"); |
810 | |
|
811 | 0 | if (png_ptr == NULL) |
812 | 0 | return; |
813 | | |
814 | 0 | #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED |
815 | 0 | if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0 && |
816 | 0 | (png_ptr->flags & PNG_FLAG_ROW_INIT) != 0) |
817 | 0 | { |
818 | 0 | png_app_error(png_ptr, |
819 | 0 | "info change after png_start_read_image or png_read_update_info"); |
820 | 0 | return; |
821 | 0 | } |
822 | 0 | #endif |
823 | | |
824 | 0 | png_ptr->user_transform_ptr = user_transform_ptr; |
825 | 0 | png_ptr->user_transform_depth = (png_byte)user_transform_depth; |
826 | 0 | png_ptr->user_transform_channels = (png_byte)user_transform_channels; |
827 | 0 | } |
828 | | #endif |
829 | | |
830 | | /* This function returns a pointer to the user_transform_ptr associated with |
831 | | * the user transform functions. The application should free any memory |
832 | | * associated with this pointer before png_write_destroy and png_read_destroy |
833 | | * are called. |
834 | | */ |
835 | | #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED |
836 | | png_voidp PNGAPI |
837 | | png_get_user_transform_ptr(png_const_structrp png_ptr) |
838 | 0 | { |
839 | 0 | if (png_ptr == NULL) |
840 | 0 | return NULL; |
841 | | |
842 | 0 | return png_ptr->user_transform_ptr; |
843 | 0 | } |
844 | | #endif |
845 | | |
846 | | #ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED |
847 | | png_uint_32 PNGAPI |
848 | | png_get_current_row_number(png_const_structrp png_ptr) |
849 | 0 | { |
850 | | /* See the comments in png.h - this is the sub-image row when reading an |
851 | | * interlaced image. |
852 | | */ |
853 | 0 | if (png_ptr != NULL) |
854 | 0 | return png_ptr->row_number; |
855 | | |
856 | 0 | return PNG_UINT_32_MAX; /* help the app not to fail silently */ |
857 | 0 | } |
858 | | |
859 | | png_byte PNGAPI |
860 | | png_get_current_pass_number(png_const_structrp png_ptr) |
861 | 0 | { |
862 | 0 | if (png_ptr != NULL) |
863 | 0 | return png_ptr->pass; |
864 | 0 | return 8; /* invalid */ |
865 | 0 | } |
866 | | #endif /* USER_TRANSFORM_INFO */ |
867 | | #endif /* READ_USER_TRANSFORM || WRITE_USER_TRANSFORM */ |
868 | | #endif /* READ || WRITE */ |