|
1 |
|
2 /* pngtrans.c - transforms the data in a row (used by both readers and writers) |
|
3 * |
|
4 * Last changed in libpng 1.2.30 [August 15, 2008] |
|
5 * For conditions of distribution and use, see copyright notice in png.h |
|
6 * Copyright (c) 1998-2008 Glenn Randers-Pehrson |
|
7 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) |
|
8 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) |
|
9 */ |
|
10 |
|
11 #define PNG_INTERNAL |
|
12 #include "png.h" |
|
13 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) |
|
14 |
|
15 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) |
|
16 /* turn on BGR-to-RGB mapping */ |
|
17 void PNGAPI |
|
18 png_set_bgr(png_structp png_ptr) |
|
19 { |
|
20 png_debug(1, "in png_set_bgr\n"); |
|
21 if (png_ptr == NULL) return; |
|
22 png_ptr->transformations |= PNG_BGR; |
|
23 } |
|
24 #endif |
|
25 |
|
26 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) |
|
27 /* turn on 16 bit byte swapping */ |
|
28 void PNGAPI |
|
29 png_set_swap(png_structp png_ptr) |
|
30 { |
|
31 png_debug(1, "in png_set_swap\n"); |
|
32 if (png_ptr == NULL) return; |
|
33 if (png_ptr->bit_depth == 16) |
|
34 png_ptr->transformations |= PNG_SWAP_BYTES; |
|
35 } |
|
36 #endif |
|
37 |
|
38 #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED) |
|
39 /* turn on pixel packing */ |
|
40 void PNGAPI |
|
41 png_set_packing(png_structp png_ptr) |
|
42 { |
|
43 png_debug(1, "in png_set_packing\n"); |
|
44 if (png_ptr == NULL) return; |
|
45 if (png_ptr->bit_depth < 8) |
|
46 { |
|
47 png_ptr->transformations |= PNG_PACK; |
|
48 png_ptr->usr_bit_depth = 8; |
|
49 } |
|
50 } |
|
51 #endif |
|
52 |
|
53 #if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED) |
|
54 /* turn on packed pixel swapping */ |
|
55 void PNGAPI |
|
56 png_set_packswap(png_structp png_ptr) |
|
57 { |
|
58 png_debug(1, "in png_set_packswap\n"); |
|
59 if (png_ptr == NULL) return; |
|
60 if (png_ptr->bit_depth < 8) |
|
61 png_ptr->transformations |= PNG_PACKSWAP; |
|
62 } |
|
63 #endif |
|
64 |
|
65 #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) |
|
66 void PNGAPI |
|
67 png_set_shift(png_structp png_ptr, png_color_8p true_bits) |
|
68 { |
|
69 png_debug(1, "in png_set_shift\n"); |
|
70 if (png_ptr == NULL) return; |
|
71 png_ptr->transformations |= PNG_SHIFT; |
|
72 png_ptr->shift = *true_bits; |
|
73 } |
|
74 #endif |
|
75 |
|
76 #if defined(PNG_READ_INTERLACING_SUPPORTED) || \ |
|
77 defined(PNG_WRITE_INTERLACING_SUPPORTED) |
|
78 int PNGAPI |
|
79 png_set_interlace_handling(png_structp png_ptr) |
|
80 { |
|
81 png_debug(1, "in png_set_interlace handling\n"); |
|
82 if (png_ptr && png_ptr->interlaced) |
|
83 { |
|
84 png_ptr->transformations |= PNG_INTERLACE; |
|
85 return (7); |
|
86 } |
|
87 |
|
88 return (1); |
|
89 } |
|
90 #endif |
|
91 |
|
92 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) |
|
93 /* Add a filler byte on read, or remove a filler or alpha byte on write. |
|
94 * The filler type has changed in v0.95 to allow future 2-byte fillers |
|
95 * for 48-bit input data, as well as to avoid problems with some compilers |
|
96 * that don't like bytes as parameters. |
|
97 */ |
|
98 void PNGAPI |
|
99 png_set_filler(png_structp png_ptr, png_uint_32 filler, int filler_loc) |
|
100 { |
|
101 png_debug(1, "in png_set_filler\n"); |
|
102 if (png_ptr == NULL) return; |
|
103 png_ptr->transformations |= PNG_FILLER; |
|
104 png_ptr->filler = (png_byte)filler; |
|
105 if (filler_loc == PNG_FILLER_AFTER) |
|
106 png_ptr->flags |= PNG_FLAG_FILLER_AFTER; |
|
107 else |
|
108 png_ptr->flags &= ~PNG_FLAG_FILLER_AFTER; |
|
109 |
|
110 /* This should probably go in the "do_read_filler" routine. |
|
111 * I attempted to do that in libpng-1.0.1a but that caused problems |
|
112 * so I restored it in libpng-1.0.2a |
|
113 */ |
|
114 |
|
115 if (png_ptr->color_type == PNG_COLOR_TYPE_RGB) |
|
116 { |
|
117 png_ptr->usr_channels = 4; |
|
118 } |
|
119 |
|
120 /* Also I added this in libpng-1.0.2a (what happens when we expand |
|
121 * a less-than-8-bit grayscale to GA? */ |
|
122 |
|
123 if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY && png_ptr->bit_depth >= 8) |
|
124 { |
|
125 png_ptr->usr_channels = 2; |
|
126 } |
|
127 } |
|
128 |
|
129 #if !defined(PNG_1_0_X) |
|
130 /* Added to libpng-1.2.7 */ |
|
131 void PNGAPI |
|
132 png_set_add_alpha(png_structp png_ptr, png_uint_32 filler, int filler_loc) |
|
133 { |
|
134 png_debug(1, "in png_set_add_alpha\n"); |
|
135 if (png_ptr == NULL) return; |
|
136 png_set_filler(png_ptr, filler, filler_loc); |
|
137 png_ptr->transformations |= PNG_ADD_ALPHA; |
|
138 } |
|
139 #endif |
|
140 |
|
141 #endif |
|
142 |
|
143 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \ |
|
144 defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) |
|
145 void PNGAPI |
|
146 png_set_swap_alpha(png_structp png_ptr) |
|
147 { |
|
148 png_debug(1, "in png_set_swap_alpha\n"); |
|
149 if (png_ptr == NULL) return; |
|
150 png_ptr->transformations |= PNG_SWAP_ALPHA; |
|
151 } |
|
152 #endif |
|
153 |
|
154 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \ |
|
155 defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) |
|
156 void PNGAPI |
|
157 png_set_invert_alpha(png_structp png_ptr) |
|
158 { |
|
159 png_debug(1, "in png_set_invert_alpha\n"); |
|
160 if (png_ptr == NULL) return; |
|
161 png_ptr->transformations |= PNG_INVERT_ALPHA; |
|
162 } |
|
163 #endif |
|
164 |
|
165 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) |
|
166 void PNGAPI |
|
167 png_set_invert_mono(png_structp png_ptr) |
|
168 { |
|
169 png_debug(1, "in png_set_invert_mono\n"); |
|
170 if (png_ptr == NULL) return; |
|
171 png_ptr->transformations |= PNG_INVERT_MONO; |
|
172 } |
|
173 |
|
174 /* invert monochrome grayscale data */ |
|
175 void /* PRIVATE */ |
|
176 png_do_invert(png_row_infop row_info, png_bytep row) |
|
177 { |
|
178 png_debug(1, "in png_do_invert\n"); |
|
179 /* This test removed from libpng version 1.0.13 and 1.2.0: |
|
180 * if (row_info->bit_depth == 1 && |
|
181 */ |
|
182 #if defined(PNG_USELESS_TESTS_SUPPORTED) |
|
183 if (row == NULL || row_info == NULL) |
|
184 return; |
|
185 #endif |
|
186 if (row_info->color_type == PNG_COLOR_TYPE_GRAY) |
|
187 { |
|
188 png_bytep rp = row; |
|
189 png_uint_32 i; |
|
190 png_uint_32 istop = row_info->rowbytes; |
|
191 |
|
192 for (i = 0; i < istop; i++) |
|
193 { |
|
194 *rp = (png_byte)(~(*rp)); |
|
195 rp++; |
|
196 } |
|
197 } |
|
198 else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA && |
|
199 row_info->bit_depth == 8) |
|
200 { |
|
201 png_bytep rp = row; |
|
202 png_uint_32 i; |
|
203 png_uint_32 istop = row_info->rowbytes; |
|
204 |
|
205 for (i = 0; i < istop; i+=2) |
|
206 { |
|
207 *rp = (png_byte)(~(*rp)); |
|
208 rp+=2; |
|
209 } |
|
210 } |
|
211 else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA && |
|
212 row_info->bit_depth == 16) |
|
213 { |
|
214 png_bytep rp = row; |
|
215 png_uint_32 i; |
|
216 png_uint_32 istop = row_info->rowbytes; |
|
217 |
|
218 for (i = 0; i < istop; i+=4) |
|
219 { |
|
220 *rp = (png_byte)(~(*rp)); |
|
221 *(rp+1) = (png_byte)(~(*(rp+1))); |
|
222 rp+=4; |
|
223 } |
|
224 } |
|
225 } |
|
226 #endif |
|
227 |
|
228 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) |
|
229 /* swaps byte order on 16 bit depth images */ |
|
230 void /* PRIVATE */ |
|
231 png_do_swap(png_row_infop row_info, png_bytep row) |
|
232 { |
|
233 png_debug(1, "in png_do_swap\n"); |
|
234 if ( |
|
235 #if defined(PNG_USELESS_TESTS_SUPPORTED) |
|
236 row != NULL && row_info != NULL && |
|
237 #endif |
|
238 row_info->bit_depth == 16) |
|
239 { |
|
240 png_bytep rp = row; |
|
241 png_uint_32 i; |
|
242 png_uint_32 istop= row_info->width * row_info->channels; |
|
243 |
|
244 for (i = 0; i < istop; i++, rp += 2) |
|
245 { |
|
246 png_byte t = *rp; |
|
247 *rp = *(rp + 1); |
|
248 *(rp + 1) = t; |
|
249 } |
|
250 } |
|
251 } |
|
252 #endif |
|
253 |
|
254 #if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED) |
|
255 static PNG_CONST png_byte onebppswaptable[256] = { |
|
256 0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, |
|
257 0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0, |
|
258 0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8, |
|
259 0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8, |
|
260 0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4, |
|
261 0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4, |
|
262 0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC, |
|
263 0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC, |
|
264 0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2, |
|
265 0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2, |
|
266 0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA, |
|
267 0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA, |
|
268 0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6, |
|
269 0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6, |
|
270 0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE, |
|
271 0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE, |
|
272 0x01, 0x81, 0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1, |
|
273 0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1, |
|
274 0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9, |
|
275 0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9, |
|
276 0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5, |
|
277 0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5, |
|
278 0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD, 0x6D, 0xED, |
|
279 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD, |
|
280 0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3, |
|
281 0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3, |
|
282 0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB, |
|
283 0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB, |
|
284 0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7, |
|
285 0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7, |
|
286 0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF, |
|
287 0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF |
|
288 }; |
|
289 |
|
290 static PNG_CONST png_byte twobppswaptable[256] = { |
|
291 0x00, 0x40, 0x80, 0xC0, 0x10, 0x50, 0x90, 0xD0, |
|
292 0x20, 0x60, 0xA0, 0xE0, 0x30, 0x70, 0xB0, 0xF0, |
|
293 0x04, 0x44, 0x84, 0xC4, 0x14, 0x54, 0x94, 0xD4, |
|
294 0x24, 0x64, 0xA4, 0xE4, 0x34, 0x74, 0xB4, 0xF4, |
|
295 0x08, 0x48, 0x88, 0xC8, 0x18, 0x58, 0x98, 0xD8, |
|
296 0x28, 0x68, 0xA8, 0xE8, 0x38, 0x78, 0xB8, 0xF8, |
|
297 0x0C, 0x4C, 0x8C, 0xCC, 0x1C, 0x5C, 0x9C, 0xDC, |
|
298 0x2C, 0x6C, 0xAC, 0xEC, 0x3C, 0x7C, 0xBC, 0xFC, |
|
299 0x01, 0x41, 0x81, 0xC1, 0x11, 0x51, 0x91, 0xD1, |
|
300 0x21, 0x61, 0xA1, 0xE1, 0x31, 0x71, 0xB1, 0xF1, |
|
301 0x05, 0x45, 0x85, 0xC5, 0x15, 0x55, 0x95, 0xD5, |
|
302 0x25, 0x65, 0xA5, 0xE5, 0x35, 0x75, 0xB5, 0xF5, |
|
303 0x09, 0x49, 0x89, 0xC9, 0x19, 0x59, 0x99, 0xD9, |
|
304 0x29, 0x69, 0xA9, 0xE9, 0x39, 0x79, 0xB9, 0xF9, |
|
305 0x0D, 0x4D, 0x8D, 0xCD, 0x1D, 0x5D, 0x9D, 0xDD, |
|
306 0x2D, 0x6D, 0xAD, 0xED, 0x3D, 0x7D, 0xBD, 0xFD, |
|
307 0x02, 0x42, 0x82, 0xC2, 0x12, 0x52, 0x92, 0xD2, |
|
308 0x22, 0x62, 0xA2, 0xE2, 0x32, 0x72, 0xB2, 0xF2, |
|
309 0x06, 0x46, 0x86, 0xC6, 0x16, 0x56, 0x96, 0xD6, |
|
310 0x26, 0x66, 0xA6, 0xE6, 0x36, 0x76, 0xB6, 0xF6, |
|
311 0x0A, 0x4A, 0x8A, 0xCA, 0x1A, 0x5A, 0x9A, 0xDA, |
|
312 0x2A, 0x6A, 0xAA, 0xEA, 0x3A, 0x7A, 0xBA, 0xFA, |
|
313 0x0E, 0x4E, 0x8E, 0xCE, 0x1E, 0x5E, 0x9E, 0xDE, |
|
314 0x2E, 0x6E, 0xAE, 0xEE, 0x3E, 0x7E, 0xBE, 0xFE, |
|
315 0x03, 0x43, 0x83, 0xC3, 0x13, 0x53, 0x93, 0xD3, |
|
316 0x23, 0x63, 0xA3, 0xE3, 0x33, 0x73, 0xB3, 0xF3, |
|
317 0x07, 0x47, 0x87, 0xC7, 0x17, 0x57, 0x97, 0xD7, |
|
318 0x27, 0x67, 0xA7, 0xE7, 0x37, 0x77, 0xB7, 0xF7, |
|
319 0x0B, 0x4B, 0x8B, 0xCB, 0x1B, 0x5B, 0x9B, 0xDB, |
|
320 0x2B, 0x6B, 0xAB, 0xEB, 0x3B, 0x7B, 0xBB, 0xFB, |
|
321 0x0F, 0x4F, 0x8F, 0xCF, 0x1F, 0x5F, 0x9F, 0xDF, |
|
322 0x2F, 0x6F, 0xAF, 0xEF, 0x3F, 0x7F, 0xBF, 0xFF |
|
323 }; |
|
324 |
|
325 static PNG_CONST png_byte fourbppswaptable[256] = { |
|
326 0x00, 0x10, 0x20, 0x30, 0x40, 0x50, 0x60, 0x70, |
|
327 0x80, 0x90, 0xA0, 0xB0, 0xC0, 0xD0, 0xE0, 0xF0, |
|
328 0x01, 0x11, 0x21, 0x31, 0x41, 0x51, 0x61, 0x71, |
|
329 0x81, 0x91, 0xA1, 0xB1, 0xC1, 0xD1, 0xE1, 0xF1, |
|
330 0x02, 0x12, 0x22, 0x32, 0x42, 0x52, 0x62, 0x72, |
|
331 0x82, 0x92, 0xA2, 0xB2, 0xC2, 0xD2, 0xE2, 0xF2, |
|
332 0x03, 0x13, 0x23, 0x33, 0x43, 0x53, 0x63, 0x73, |
|
333 0x83, 0x93, 0xA3, 0xB3, 0xC3, 0xD3, 0xE3, 0xF3, |
|
334 0x04, 0x14, 0x24, 0x34, 0x44, 0x54, 0x64, 0x74, |
|
335 0x84, 0x94, 0xA4, 0xB4, 0xC4, 0xD4, 0xE4, 0xF4, |
|
336 0x05, 0x15, 0x25, 0x35, 0x45, 0x55, 0x65, 0x75, |
|
337 0x85, 0x95, 0xA5, 0xB5, 0xC5, 0xD5, 0xE5, 0xF5, |
|
338 0x06, 0x16, 0x26, 0x36, 0x46, 0x56, 0x66, 0x76, |
|
339 0x86, 0x96, 0xA6, 0xB6, 0xC6, 0xD6, 0xE6, 0xF6, |
|
340 0x07, 0x17, 0x27, 0x37, 0x47, 0x57, 0x67, 0x77, |
|
341 0x87, 0x97, 0xA7, 0xB7, 0xC7, 0xD7, 0xE7, 0xF7, |
|
342 0x08, 0x18, 0x28, 0x38, 0x48, 0x58, 0x68, 0x78, |
|
343 0x88, 0x98, 0xA8, 0xB8, 0xC8, 0xD8, 0xE8, 0xF8, |
|
344 0x09, 0x19, 0x29, 0x39, 0x49, 0x59, 0x69, 0x79, |
|
345 0x89, 0x99, 0xA9, 0xB9, 0xC9, 0xD9, 0xE9, 0xF9, |
|
346 0x0A, 0x1A, 0x2A, 0x3A, 0x4A, 0x5A, 0x6A, 0x7A, |
|
347 0x8A, 0x9A, 0xAA, 0xBA, 0xCA, 0xDA, 0xEA, 0xFA, |
|
348 0x0B, 0x1B, 0x2B, 0x3B, 0x4B, 0x5B, 0x6B, 0x7B, |
|
349 0x8B, 0x9B, 0xAB, 0xBB, 0xCB, 0xDB, 0xEB, 0xFB, |
|
350 0x0C, 0x1C, 0x2C, 0x3C, 0x4C, 0x5C, 0x6C, 0x7C, |
|
351 0x8C, 0x9C, 0xAC, 0xBC, 0xCC, 0xDC, 0xEC, 0xFC, |
|
352 0x0D, 0x1D, 0x2D, 0x3D, 0x4D, 0x5D, 0x6D, 0x7D, |
|
353 0x8D, 0x9D, 0xAD, 0xBD, 0xCD, 0xDD, 0xED, 0xFD, |
|
354 0x0E, 0x1E, 0x2E, 0x3E, 0x4E, 0x5E, 0x6E, 0x7E, |
|
355 0x8E, 0x9E, 0xAE, 0xBE, 0xCE, 0xDE, 0xEE, 0xFE, |
|
356 0x0F, 0x1F, 0x2F, 0x3F, 0x4F, 0x5F, 0x6F, 0x7F, |
|
357 0x8F, 0x9F, 0xAF, 0xBF, 0xCF, 0xDF, 0xEF, 0xFF |
|
358 }; |
|
359 |
|
360 /* swaps pixel packing order within bytes */ |
|
361 void /* PRIVATE */ |
|
362 png_do_packswap(png_row_infop row_info, png_bytep row) |
|
363 { |
|
364 png_debug(1, "in png_do_packswap\n"); |
|
365 if ( |
|
366 #if defined(PNG_USELESS_TESTS_SUPPORTED) |
|
367 row != NULL && row_info != NULL && |
|
368 #endif |
|
369 row_info->bit_depth < 8) |
|
370 { |
|
371 png_bytep rp, end, table; |
|
372 |
|
373 end = row + row_info->rowbytes; |
|
374 |
|
375 if (row_info->bit_depth == 1) |
|
376 table = (png_bytep)onebppswaptable; |
|
377 else if (row_info->bit_depth == 2) |
|
378 table = (png_bytep)twobppswaptable; |
|
379 else if (row_info->bit_depth == 4) |
|
380 table = (png_bytep)fourbppswaptable; |
|
381 else |
|
382 return; |
|
383 |
|
384 for (rp = row; rp < end; rp++) |
|
385 *rp = table[*rp]; |
|
386 } |
|
387 } |
|
388 #endif /* PNG_READ_PACKSWAP_SUPPORTED or PNG_WRITE_PACKSWAP_SUPPORTED */ |
|
389 |
|
390 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \ |
|
391 defined(PNG_READ_STRIP_ALPHA_SUPPORTED) |
|
392 /* remove filler or alpha byte(s) */ |
|
393 void /* PRIVATE */ |
|
394 png_do_strip_filler(png_row_infop row_info, png_bytep row, png_uint_32 flags) |
|
395 { |
|
396 png_debug(1, "in png_do_strip_filler\n"); |
|
397 #if defined(PNG_USELESS_TESTS_SUPPORTED) |
|
398 if (row != NULL && row_info != NULL) |
|
399 #endif |
|
400 { |
|
401 png_bytep sp=row; |
|
402 png_bytep dp=row; |
|
403 png_uint_32 row_width=row_info->width; |
|
404 png_uint_32 i; |
|
405 |
|
406 if ((row_info->color_type == PNG_COLOR_TYPE_RGB || |
|
407 (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA && |
|
408 (flags & PNG_FLAG_STRIP_ALPHA))) && |
|
409 row_info->channels == 4) |
|
410 { |
|
411 if (row_info->bit_depth == 8) |
|
412 { |
|
413 /* This converts from RGBX or RGBA to RGB */ |
|
414 if (flags & PNG_FLAG_FILLER_AFTER) |
|
415 { |
|
416 dp+=3; sp+=4; |
|
417 for (i = 1; i < row_width; i++) |
|
418 { |
|
419 *dp++ = *sp++; |
|
420 *dp++ = *sp++; |
|
421 *dp++ = *sp++; |
|
422 sp++; |
|
423 } |
|
424 } |
|
425 /* This converts from XRGB or ARGB to RGB */ |
|
426 else |
|
427 { |
|
428 for (i = 0; i < row_width; i++) |
|
429 { |
|
430 sp++; |
|
431 *dp++ = *sp++; |
|
432 *dp++ = *sp++; |
|
433 *dp++ = *sp++; |
|
434 } |
|
435 } |
|
436 row_info->pixel_depth = 24; |
|
437 row_info->rowbytes = row_width * 3; |
|
438 } |
|
439 else /* if (row_info->bit_depth == 16) */ |
|
440 { |
|
441 if (flags & PNG_FLAG_FILLER_AFTER) |
|
442 { |
|
443 /* This converts from RRGGBBXX or RRGGBBAA to RRGGBB */ |
|
444 sp += 8; dp += 6; |
|
445 for (i = 1; i < row_width; i++) |
|
446 { |
|
447 /* This could be (although png_memcpy is probably slower): |
|
448 png_memcpy(dp, sp, 6); |
|
449 sp += 8; |
|
450 dp += 6; |
|
451 */ |
|
452 |
|
453 *dp++ = *sp++; |
|
454 *dp++ = *sp++; |
|
455 *dp++ = *sp++; |
|
456 *dp++ = *sp++; |
|
457 *dp++ = *sp++; |
|
458 *dp++ = *sp++; |
|
459 sp += 2; |
|
460 } |
|
461 } |
|
462 else |
|
463 { |
|
464 /* This converts from XXRRGGBB or AARRGGBB to RRGGBB */ |
|
465 for (i = 0; i < row_width; i++) |
|
466 { |
|
467 /* This could be (although png_memcpy is probably slower): |
|
468 png_memcpy(dp, sp, 6); |
|
469 sp += 8; |
|
470 dp += 6; |
|
471 */ |
|
472 |
|
473 sp+=2; |
|
474 *dp++ = *sp++; |
|
475 *dp++ = *sp++; |
|
476 *dp++ = *sp++; |
|
477 *dp++ = *sp++; |
|
478 *dp++ = *sp++; |
|
479 *dp++ = *sp++; |
|
480 } |
|
481 } |
|
482 row_info->pixel_depth = 48; |
|
483 row_info->rowbytes = row_width * 6; |
|
484 } |
|
485 row_info->channels = 3; |
|
486 } |
|
487 else if ((row_info->color_type == PNG_COLOR_TYPE_GRAY || |
|
488 (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA && |
|
489 (flags & PNG_FLAG_STRIP_ALPHA))) && |
|
490 row_info->channels == 2) |
|
491 { |
|
492 if (row_info->bit_depth == 8) |
|
493 { |
|
494 /* This converts from GX or GA to G */ |
|
495 if (flags & PNG_FLAG_FILLER_AFTER) |
|
496 { |
|
497 for (i = 0; i < row_width; i++) |
|
498 { |
|
499 *dp++ = *sp++; |
|
500 sp++; |
|
501 } |
|
502 } |
|
503 /* This converts from XG or AG to G */ |
|
504 else |
|
505 { |
|
506 for (i = 0; i < row_width; i++) |
|
507 { |
|
508 sp++; |
|
509 *dp++ = *sp++; |
|
510 } |
|
511 } |
|
512 row_info->pixel_depth = 8; |
|
513 row_info->rowbytes = row_width; |
|
514 } |
|
515 else /* if (row_info->bit_depth == 16) */ |
|
516 { |
|
517 if (flags & PNG_FLAG_FILLER_AFTER) |
|
518 { |
|
519 /* This converts from GGXX or GGAA to GG */ |
|
520 sp += 4; dp += 2; |
|
521 for (i = 1; i < row_width; i++) |
|
522 { |
|
523 *dp++ = *sp++; |
|
524 *dp++ = *sp++; |
|
525 sp += 2; |
|
526 } |
|
527 } |
|
528 else |
|
529 { |
|
530 /* This converts from XXGG or AAGG to GG */ |
|
531 for (i = 0; i < row_width; i++) |
|
532 { |
|
533 sp += 2; |
|
534 *dp++ = *sp++; |
|
535 *dp++ = *sp++; |
|
536 } |
|
537 } |
|
538 row_info->pixel_depth = 16; |
|
539 row_info->rowbytes = row_width * 2; |
|
540 } |
|
541 row_info->channels = 1; |
|
542 } |
|
543 if (flags & PNG_FLAG_STRIP_ALPHA) |
|
544 row_info->color_type &= ~PNG_COLOR_MASK_ALPHA; |
|
545 } |
|
546 } |
|
547 #endif |
|
548 |
|
549 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) |
|
550 /* swaps red and blue bytes within a pixel */ |
|
551 void /* PRIVATE */ |
|
552 png_do_bgr(png_row_infop row_info, png_bytep row) |
|
553 { |
|
554 png_debug(1, "in png_do_bgr\n"); |
|
555 if ( |
|
556 #if defined(PNG_USELESS_TESTS_SUPPORTED) |
|
557 row != NULL && row_info != NULL && |
|
558 #endif |
|
559 (row_info->color_type & PNG_COLOR_MASK_COLOR)) |
|
560 { |
|
561 png_uint_32 row_width = row_info->width; |
|
562 if (row_info->bit_depth == 8) |
|
563 { |
|
564 if (row_info->color_type == PNG_COLOR_TYPE_RGB) |
|
565 { |
|
566 png_bytep rp; |
|
567 png_uint_32 i; |
|
568 |
|
569 for (i = 0, rp = row; i < row_width; i++, rp += 3) |
|
570 { |
|
571 png_byte save = *rp; |
|
572 *rp = *(rp + 2); |
|
573 *(rp + 2) = save; |
|
574 } |
|
575 } |
|
576 else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
|
577 { |
|
578 png_bytep rp; |
|
579 png_uint_32 i; |
|
580 |
|
581 for (i = 0, rp = row; i < row_width; i++, rp += 4) |
|
582 { |
|
583 png_byte save = *rp; |
|
584 *rp = *(rp + 2); |
|
585 *(rp + 2) = save; |
|
586 } |
|
587 } |
|
588 } |
|
589 else if (row_info->bit_depth == 16) |
|
590 { |
|
591 if (row_info->color_type == PNG_COLOR_TYPE_RGB) |
|
592 { |
|
593 png_bytep rp; |
|
594 png_uint_32 i; |
|
595 |
|
596 for (i = 0, rp = row; i < row_width; i++, rp += 6) |
|
597 { |
|
598 png_byte save = *rp; |
|
599 *rp = *(rp + 4); |
|
600 *(rp + 4) = save; |
|
601 save = *(rp + 1); |
|
602 *(rp + 1) = *(rp + 5); |
|
603 *(rp + 5) = save; |
|
604 } |
|
605 } |
|
606 else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
|
607 { |
|
608 png_bytep rp; |
|
609 png_uint_32 i; |
|
610 |
|
611 for (i = 0, rp = row; i < row_width; i++, rp += 8) |
|
612 { |
|
613 png_byte save = *rp; |
|
614 *rp = *(rp + 4); |
|
615 *(rp + 4) = save; |
|
616 save = *(rp + 1); |
|
617 *(rp + 1) = *(rp + 5); |
|
618 *(rp + 5) = save; |
|
619 } |
|
620 } |
|
621 } |
|
622 } |
|
623 } |
|
624 #endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */ |
|
625 |
|
626 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ |
|
627 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \ |
|
628 defined(PNG_LEGACY_SUPPORTED) |
|
629 void PNGAPI |
|
630 png_set_user_transform_info(png_structp png_ptr, png_voidp |
|
631 user_transform_ptr, int user_transform_depth, int user_transform_channels) |
|
632 { |
|
633 png_debug(1, "in png_set_user_transform_info\n"); |
|
634 if (png_ptr == NULL) return; |
|
635 #if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) |
|
636 png_ptr->user_transform_ptr = user_transform_ptr; |
|
637 png_ptr->user_transform_depth = (png_byte)user_transform_depth; |
|
638 png_ptr->user_transform_channels = (png_byte)user_transform_channels; |
|
639 #else |
|
640 if (user_transform_ptr || user_transform_depth || user_transform_channels) |
|
641 png_warning(png_ptr, |
|
642 "This version of libpng does not support user transform info"); |
|
643 #endif |
|
644 } |
|
645 #endif |
|
646 |
|
647 /* This function returns a pointer to the user_transform_ptr associated with |
|
648 * the user transform functions. The application should free any memory |
|
649 * associated with this pointer before png_write_destroy and png_read_destroy |
|
650 * are called. |
|
651 */ |
|
652 png_voidp PNGAPI |
|
653 png_get_user_transform_ptr(png_structp png_ptr) |
|
654 { |
|
655 if (png_ptr == NULL) return (NULL); |
|
656 #if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) |
|
657 return ((png_voidp)png_ptr->user_transform_ptr); |
|
658 #else |
|
659 return (NULL); |
|
660 #endif |
|
661 } |
|
662 #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */ |