Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2 | /* pngwtran.c - transforms the data in a row for PNG writers |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 3 | * |
Glenn Randers-Pehrson | 65a2237 | 2010-03-03 05:38:29 -0600 | [diff] [blame] | 4 | * Last changed in libpng 1.5.0 [March 3, 2010] |
Glenn Randers-Pehrson | e69b55d | 2010-01-01 10:29:06 -0600 | [diff] [blame] | 5 | * Copyright (c) 1998-2010 Glenn Randers-Pehrson |
Glenn Randers-Pehrson | d436672 | 2000-06-04 14:29:29 -0500 | [diff] [blame] | 6 | * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) |
| 7 | * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) |
Glenn Randers-Pehrson | 3e61d79 | 2009-06-24 09:31:28 -0500 | [diff] [blame] | 8 | * |
Glenn Randers-Pehrson | bfbf865 | 2009-06-26 21:46:52 -0500 | [diff] [blame] | 9 | * This code is released under the libpng license. |
Glenn Randers-Pehrson | c332bbc | 2009-06-25 13:43:50 -0500 | [diff] [blame] | 10 | * For conditions of distribution and use, see the disclaimer |
Glenn Randers-Pehrson | 037023b | 2009-06-24 10:27:36 -0500 | [diff] [blame] | 11 | * and license in png.h |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 12 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 13 | |
Glenn Randers-Pehrson | f979531 | 2010-02-09 01:16:48 -0600 | [diff] [blame] | 14 | #define PNG_EXPOSE_INTERNAL_STRUCTURES |
Glenn Randers-Pehrson | 03f9b02 | 2009-12-04 08:40:41 -0600 | [diff] [blame] | 15 | #define PNG_NO_PEDANTIC_WARNINGS |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 16 | #include "png.h" |
Glenn Randers-Pehrson | 3097f61 | 2001-05-07 14:52:45 -0500 | [diff] [blame] | 17 | #ifdef PNG_WRITE_SUPPORTED |
Glenn Randers-Pehrson | beb572e | 2006-08-19 13:59:24 -0500 | [diff] [blame] | 18 | #include "pngpriv.h" |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 19 | |
Glenn Randers-Pehrson | 345bc27 | 1998-06-14 14:43:31 -0500 | [diff] [blame] | 20 | /* Transform the data according to the user's wishes. The order of |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 21 | * transformations is significant. |
| 22 | */ |
Glenn Randers-Pehrson | 7529457 | 2000-05-06 14:09:57 -0500 | [diff] [blame] | 23 | void /* PRIVATE */ |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 24 | png_do_write_transformations(png_structp png_ptr) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 25 | { |
Glenn Randers-Pehrson | 51650b8 | 2008-08-05 07:44:42 -0500 | [diff] [blame] | 26 | png_debug(1, "in png_do_write_transformations"); |
Glenn Randers-Pehrson | 08a3343 | 1998-03-07 06:06:55 -0600 | [diff] [blame] | 27 | |
Glenn Randers-Pehrson | 166c5a3 | 1999-12-10 09:43:02 -0600 | [diff] [blame] | 28 | if (png_ptr == NULL) |
| 29 | return; |
| 30 | |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 31 | #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED |
Glenn Randers-Pehrson | 08a3343 | 1998-03-07 06:06:55 -0600 | [diff] [blame] | 32 | if (png_ptr->transformations & PNG_USER_TRANSFORM) |
Glenn Randers-Pehrson | 145f5c8 | 2008-07-10 09:13:13 -0500 | [diff] [blame] | 33 | if (png_ptr->write_user_transform_fn != NULL) |
Glenn Randers-Pehrson | e3f3c4e | 2010-02-07 18:08:50 -0600 | [diff] [blame] | 34 | (*(png_ptr->write_user_transform_fn)) /* User write transform |
| 35 | function */ |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 36 | (png_ptr, /* png_ptr */ |
| 37 | &(png_ptr->row_info), /* row_info: */ |
| 38 | /* png_uint_32 width; width of row */ |
| 39 | /* png_uint_32 rowbytes; number of bytes in row */ |
| 40 | /* png_byte color_type; color type of pixels */ |
| 41 | /* png_byte bit_depth; bit depth of samples */ |
| 42 | /* png_byte channels; number of channels (1-4) */ |
| 43 | /* png_byte pixel_depth; bits per pixel (depth*channels) */ |
| 44 | png_ptr->row_buf + 1); /* start of pixel data for row */ |
Glenn Randers-Pehrson | 08a3343 | 1998-03-07 06:06:55 -0600 | [diff] [blame] | 45 | #endif |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 46 | #ifdef PNG_WRITE_FILLER_SUPPORTED |
Glenn Randers-Pehrson | 73b029f | 2004-11-26 17:28:09 -0600 | [diff] [blame] | 47 | if (png_ptr->transformations & PNG_FILLER) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 48 | png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1, |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 49 | png_ptr->flags); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 50 | #endif |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 51 | #ifdef PNG_WRITE_PACKSWAP_SUPPORTED |
Glenn Randers-Pehrson | 46f61e2 | 1998-01-30 21:45:12 -0600 | [diff] [blame] | 52 | if (png_ptr->transformations & PNG_PACKSWAP) |
| 53 | png_do_packswap(&(png_ptr->row_info), png_ptr->row_buf + 1); |
| 54 | #endif |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 55 | #ifdef PNG_WRITE_PACK_SUPPORTED |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 56 | if (png_ptr->transformations & PNG_PACK) |
| 57 | png_do_pack(&(png_ptr->row_info), png_ptr->row_buf + 1, |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 58 | (png_uint_32)png_ptr->bit_depth); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 59 | #endif |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 60 | #ifdef PNG_WRITE_SWAP_SUPPORTED |
Glenn Randers-Pehrson | 5c6aeb2 | 1998-12-29 11:47:59 -0600 | [diff] [blame] | 61 | if (png_ptr->transformations & PNG_SWAP_BYTES) |
| 62 | png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1); |
| 63 | #endif |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 64 | #ifdef PNG_WRITE_SHIFT_SUPPORTED |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 65 | if (png_ptr->transformations & PNG_SHIFT) |
| 66 | png_do_shift(&(png_ptr->row_info), png_ptr->row_buf + 1, |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 67 | &(png_ptr->shift)); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 68 | #endif |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 69 | #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 70 | if (png_ptr->transformations & PNG_SWAP_ALPHA) |
| 71 | png_do_write_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); |
| 72 | #endif |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 73 | #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED |
Glenn Randers-Pehrson | 9c3ab68 | 2006-02-20 22:09:05 -0600 | [diff] [blame] | 74 | if (png_ptr->transformations & PNG_INVERT_ALPHA) |
| 75 | png_do_write_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); |
| 76 | #endif |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 77 | #ifdef PNG_WRITE_BGR_SUPPORTED |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 78 | if (png_ptr->transformations & PNG_BGR) |
| 79 | png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 80 | #endif |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 81 | #ifdef PNG_WRITE_INVERT_SUPPORTED |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 82 | if (png_ptr->transformations & PNG_INVERT_MONO) |
| 83 | png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 84 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 85 | } |
| 86 | |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 87 | #ifdef PNG_WRITE_PACK_SUPPORTED |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 88 | /* Pack pixels into bytes. Pass the true bit depth in bit_depth. The |
| 89 | * row_info bit depth should be 8 (one pixel per byte). The channels |
| 90 | * should be 1 (this only happens on grayscale and paletted images). |
| 91 | */ |
Glenn Randers-Pehrson | 7529457 | 2000-05-06 14:09:57 -0500 | [diff] [blame] | 92 | void /* PRIVATE */ |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 93 | png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 94 | { |
Glenn Randers-Pehrson | 51650b8 | 2008-08-05 07:44:42 -0500 | [diff] [blame] | 95 | png_debug(1, "in png_do_pack"); |
Glenn Randers-Pehrson | da00980 | 2009-08-15 13:25:47 -0500 | [diff] [blame] | 96 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 97 | if (row_info->bit_depth == 8 && |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 98 | row_info->channels == 1) |
| 99 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 100 | switch ((int)bit_depth) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 101 | { |
| 102 | case 1: |
| 103 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 104 | png_bytep sp, dp; |
| 105 | int mask, v; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 106 | png_uint_32 i; |
| 107 | png_uint_32 row_width = row_info->width; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 108 | |
| 109 | sp = row; |
| 110 | dp = row; |
| 111 | mask = 0x80; |
| 112 | v = 0; |
Glenn Randers-Pehrson | 5c6aeb2 | 1998-12-29 11:47:59 -0600 | [diff] [blame] | 113 | |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 114 | for (i = 0; i < row_width; i++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 115 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 116 | if (*sp != 0) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 117 | v |= mask; |
| 118 | sp++; |
| 119 | if (mask > 1) |
| 120 | mask >>= 1; |
| 121 | else |
| 122 | { |
| 123 | mask = 0x80; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 124 | *dp = (png_byte)v; |
| 125 | dp++; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 126 | v = 0; |
| 127 | } |
| 128 | } |
| 129 | if (mask != 0x80) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 130 | *dp = (png_byte)v; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 131 | break; |
| 132 | } |
| 133 | case 2: |
| 134 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 135 | png_bytep sp, dp; |
| 136 | int shift, v; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 137 | png_uint_32 i; |
| 138 | png_uint_32 row_width = row_info->width; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 139 | |
| 140 | sp = row; |
| 141 | dp = row; |
| 142 | shift = 6; |
| 143 | v = 0; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 144 | for (i = 0; i < row_width; i++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 145 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 146 | png_byte value; |
| 147 | |
Glenn Randers-Pehrson | 61c32d9 | 2000-02-04 23:40:16 -0600 | [diff] [blame] | 148 | value = (png_byte)(*sp & 0x03); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 149 | v |= (value << shift); |
| 150 | if (shift == 0) |
| 151 | { |
| 152 | shift = 6; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 153 | *dp = (png_byte)v; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 154 | dp++; |
| 155 | v = 0; |
| 156 | } |
| 157 | else |
| 158 | shift -= 2; |
| 159 | sp++; |
| 160 | } |
| 161 | if (shift != 6) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 162 | *dp = (png_byte)v; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 163 | break; |
| 164 | } |
| 165 | case 4: |
| 166 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 167 | png_bytep sp, dp; |
| 168 | int shift, v; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 169 | png_uint_32 i; |
| 170 | png_uint_32 row_width = row_info->width; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 171 | |
| 172 | sp = row; |
| 173 | dp = row; |
| 174 | shift = 4; |
| 175 | v = 0; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 176 | for (i = 0; i < row_width; i++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 177 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 178 | png_byte value; |
| 179 | |
Glenn Randers-Pehrson | 61c32d9 | 2000-02-04 23:40:16 -0600 | [diff] [blame] | 180 | value = (png_byte)(*sp & 0x0f); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 181 | v |= (value << shift); |
| 182 | |
| 183 | if (shift == 0) |
| 184 | { |
| 185 | shift = 4; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 186 | *dp = (png_byte)v; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 187 | dp++; |
| 188 | v = 0; |
| 189 | } |
| 190 | else |
| 191 | shift -= 4; |
| 192 | |
| 193 | sp++; |
| 194 | } |
| 195 | if (shift != 4) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 196 | *dp = (png_byte)v; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 197 | break; |
| 198 | } |
| 199 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 200 | row_info->bit_depth = (png_byte)bit_depth; |
| 201 | row_info->pixel_depth = (png_byte)(bit_depth * row_info->channels); |
Glenn Randers-Pehrson | 272489d | 2004-08-04 06:34:52 -0500 | [diff] [blame] | 202 | row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 203 | row_info->width); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 204 | } |
| 205 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 206 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 207 | |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 208 | #ifdef PNG_WRITE_SHIFT_SUPPORTED |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 209 | /* Shift pixel values to take advantage of whole range. Pass the |
| 210 | * true number of bits in bit_depth. The row should be packed |
| 211 | * according to row_info->bit_depth. Thus, if you had a row of |
| 212 | * bit depth 4, but the pixels only had values from 0 to 7, you |
| 213 | * would pass 3 as bit_depth, and this routine would translate the |
| 214 | * data to 0 to 15. |
| 215 | */ |
Glenn Randers-Pehrson | 7529457 | 2000-05-06 14:09:57 -0500 | [diff] [blame] | 216 | void /* PRIVATE */ |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 217 | png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 218 | { |
Glenn Randers-Pehrson | 51650b8 | 2008-08-05 07:44:42 -0500 | [diff] [blame] | 219 | png_debug(1, "in png_do_shift"); |
Glenn Randers-Pehrson | da00980 | 2009-08-15 13:25:47 -0500 | [diff] [blame] | 220 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 221 | if ( |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 222 | row_info->color_type != PNG_COLOR_TYPE_PALETTE) |
| 223 | { |
| 224 | int shift_start[4], shift_dec[4]; |
Glenn Randers-Pehrson | d0dce40 | 1998-05-09 10:02:29 -0500 | [diff] [blame] | 225 | int channels = 0; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 226 | |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 227 | if (row_info->color_type & PNG_COLOR_MASK_COLOR) |
| 228 | { |
| 229 | shift_start[channels] = row_info->bit_depth - bit_depth->red; |
| 230 | shift_dec[channels] = bit_depth->red; |
| 231 | channels++; |
| 232 | shift_start[channels] = row_info->bit_depth - bit_depth->green; |
| 233 | shift_dec[channels] = bit_depth->green; |
| 234 | channels++; |
| 235 | shift_start[channels] = row_info->bit_depth - bit_depth->blue; |
| 236 | shift_dec[channels] = bit_depth->blue; |
| 237 | channels++; |
| 238 | } |
| 239 | else |
| 240 | { |
| 241 | shift_start[channels] = row_info->bit_depth - bit_depth->gray; |
| 242 | shift_dec[channels] = bit_depth->gray; |
| 243 | channels++; |
| 244 | } |
| 245 | if (row_info->color_type & PNG_COLOR_MASK_ALPHA) |
| 246 | { |
| 247 | shift_start[channels] = row_info->bit_depth - bit_depth->alpha; |
| 248 | shift_dec[channels] = bit_depth->alpha; |
| 249 | channels++; |
| 250 | } |
| 251 | |
Glenn Randers-Pehrson | 4bb4d01 | 2009-05-20 12:45:29 -0500 | [diff] [blame] | 252 | /* With low row depths, could only be grayscale, so one channel */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 253 | if (row_info->bit_depth < 8) |
| 254 | { |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 255 | png_bytep bp = row; |
| 256 | png_uint_32 i; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 257 | png_byte mask; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 258 | png_uint_32 row_bytes = row_info->rowbytes; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 259 | |
| 260 | if (bit_depth->gray == 1 && row_info->bit_depth == 2) |
| 261 | mask = 0x55; |
| 262 | else if (row_info->bit_depth == 4 && bit_depth->gray == 3) |
| 263 | mask = 0x11; |
| 264 | else |
| 265 | mask = 0xff; |
| 266 | |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 267 | for (i = 0; i < row_bytes; i++, bp++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 268 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 269 | png_uint_16 v; |
| 270 | int j; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 271 | |
| 272 | v = *bp; |
| 273 | *bp = 0; |
| 274 | for (j = shift_start[0]; j > -shift_dec[0]; j -= shift_dec[0]) |
| 275 | { |
| 276 | if (j > 0) |
| 277 | *bp |= (png_byte)((v << j) & 0xff); |
| 278 | else |
| 279 | *bp |= (png_byte)((v >> (-j)) & mask); |
| 280 | } |
| 281 | } |
| 282 | } |
| 283 | else if (row_info->bit_depth == 8) |
| 284 | { |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 285 | png_bytep bp = row; |
| 286 | png_uint_32 i; |
Glenn Randers-Pehrson | d0dce40 | 1998-05-09 10:02:29 -0500 | [diff] [blame] | 287 | png_uint_32 istop = channels * row_info->width; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 288 | |
Glenn Randers-Pehrson | d0dce40 | 1998-05-09 10:02:29 -0500 | [diff] [blame] | 289 | for (i = 0; i < istop; i++, bp++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 290 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 291 | |
Glenn Randers-Pehrson | d0dce40 | 1998-05-09 10:02:29 -0500 | [diff] [blame] | 292 | png_uint_16 v; |
| 293 | int j; |
| 294 | int c = (int)(i%channels); |
| 295 | |
| 296 | v = *bp; |
| 297 | *bp = 0; |
| 298 | for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c]) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 299 | { |
Glenn Randers-Pehrson | d0dce40 | 1998-05-09 10:02:29 -0500 | [diff] [blame] | 300 | if (j > 0) |
| 301 | *bp |= (png_byte)((v << j) & 0xff); |
| 302 | else |
| 303 | *bp |= (png_byte)((v >> (-j)) & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 304 | } |
| 305 | } |
| 306 | } |
| 307 | else |
| 308 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 309 | png_bytep bp; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 310 | png_uint_32 i; |
Glenn Randers-Pehrson | d0dce40 | 1998-05-09 10:02:29 -0500 | [diff] [blame] | 311 | png_uint_32 istop = channels * row_info->width; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 312 | |
Glenn Randers-Pehrson | d0dce40 | 1998-05-09 10:02:29 -0500 | [diff] [blame] | 313 | for (bp = row, i = 0; i < istop; i++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 314 | { |
Glenn Randers-Pehrson | d0dce40 | 1998-05-09 10:02:29 -0500 | [diff] [blame] | 315 | int c = (int)(i%channels); |
| 316 | png_uint_16 value, v; |
| 317 | int j; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 318 | |
Glenn Randers-Pehrson | 860ab2b | 1999-10-14 07:43:10 -0500 | [diff] [blame] | 319 | v = (png_uint_16)(((png_uint_16)(*bp) << 8) + *(bp + 1)); |
Glenn Randers-Pehrson | d0dce40 | 1998-05-09 10:02:29 -0500 | [diff] [blame] | 320 | value = 0; |
| 321 | for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c]) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 322 | { |
Glenn Randers-Pehrson | d0dce40 | 1998-05-09 10:02:29 -0500 | [diff] [blame] | 323 | if (j > 0) |
| 324 | value |= (png_uint_16)((v << j) & (png_uint_16)0xffff); |
| 325 | else |
| 326 | value |= (png_uint_16)((v >> (-j)) & (png_uint_16)0xffff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 327 | } |
Glenn Randers-Pehrson | d0dce40 | 1998-05-09 10:02:29 -0500 | [diff] [blame] | 328 | *bp++ = (png_byte)(value >> 8); |
| 329 | *bp++ = (png_byte)(value & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 330 | } |
| 331 | } |
| 332 | } |
| 333 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 334 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 335 | |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 336 | #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED |
Glenn Randers-Pehrson | 7529457 | 2000-05-06 14:09:57 -0500 | [diff] [blame] | 337 | void /* PRIVATE */ |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 338 | png_do_write_swap_alpha(png_row_infop row_info, png_bytep row) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 339 | { |
Glenn Randers-Pehrson | 51650b8 | 2008-08-05 07:44:42 -0500 | [diff] [blame] | 340 | png_debug(1, "in png_do_write_swap_alpha"); |
Glenn Randers-Pehrson | da00980 | 2009-08-15 13:25:47 -0500 | [diff] [blame] | 341 | |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 342 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 343 | if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 344 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 345 | if (row_info->bit_depth == 8) |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 346 | { |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 347 | /* This converts from ARGB to RGBA */ |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 348 | png_bytep sp, dp; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 349 | png_uint_32 i; |
| 350 | png_uint_32 row_width = row_info->width; |
| 351 | for (i = 0, sp = dp = row; i < row_width; i++) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 352 | { |
Glenn Randers-Pehrson | 896239b | 1998-04-21 15:03:57 -0500 | [diff] [blame] | 353 | png_byte save = *(sp++); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 354 | *(dp++) = *(sp++); |
| 355 | *(dp++) = *(sp++); |
| 356 | *(dp++) = *(sp++); |
| 357 | *(dp++) = save; |
| 358 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 359 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 360 | else |
| 361 | { |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 362 | /* This converts from AARRGGBB to RRGGBBAA */ |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 363 | png_bytep sp, dp; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 364 | png_uint_32 i; |
| 365 | png_uint_32 row_width = row_info->width; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 366 | |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 367 | for (i = 0, sp = dp = row; i < row_width; i++) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 368 | { |
Glenn Randers-Pehrson | 896239b | 1998-04-21 15:03:57 -0500 | [diff] [blame] | 369 | png_byte save[2]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 370 | save[0] = *(sp++); |
| 371 | save[1] = *(sp++); |
| 372 | *(dp++) = *(sp++); |
| 373 | *(dp++) = *(sp++); |
| 374 | *(dp++) = *(sp++); |
| 375 | *(dp++) = *(sp++); |
| 376 | *(dp++) = *(sp++); |
| 377 | *(dp++) = *(sp++); |
| 378 | *(dp++) = save[0]; |
| 379 | *(dp++) = save[1]; |
| 380 | } |
| 381 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 382 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 383 | else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 384 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 385 | if (row_info->bit_depth == 8) |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 386 | { |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 387 | /* This converts from AG to GA */ |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 388 | png_bytep sp, dp; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 389 | png_uint_32 i; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 390 | png_uint_32 row_width = row_info->width; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 391 | |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 392 | for (i = 0, sp = dp = row; i < row_width; i++) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 393 | { |
Glenn Randers-Pehrson | 896239b | 1998-04-21 15:03:57 -0500 | [diff] [blame] | 394 | png_byte save = *(sp++); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 395 | *(dp++) = *(sp++); |
| 396 | *(dp++) = save; |
| 397 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 398 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 399 | else |
| 400 | { |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 401 | /* This converts from AAGG to GGAA */ |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 402 | png_bytep sp, dp; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 403 | png_uint_32 i; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 404 | png_uint_32 row_width = row_info->width; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 405 | |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 406 | for (i = 0, sp = dp = row; i < row_width; i++) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 407 | { |
Glenn Randers-Pehrson | 896239b | 1998-04-21 15:03:57 -0500 | [diff] [blame] | 408 | png_byte save[2]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 409 | save[0] = *(sp++); |
| 410 | save[1] = *(sp++); |
| 411 | *(dp++) = *(sp++); |
| 412 | *(dp++) = *(sp++); |
| 413 | *(dp++) = save[0]; |
| 414 | *(dp++) = save[1]; |
| 415 | } |
| 416 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 417 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 418 | } |
| 419 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 420 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 421 | |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 422 | #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED |
Glenn Randers-Pehrson | 7529457 | 2000-05-06 14:09:57 -0500 | [diff] [blame] | 423 | void /* PRIVATE */ |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 424 | png_do_write_invert_alpha(png_row_infop row_info, png_bytep row) |
| 425 | { |
Glenn Randers-Pehrson | 51650b8 | 2008-08-05 07:44:42 -0500 | [diff] [blame] | 426 | png_debug(1, "in png_do_write_invert_alpha"); |
Glenn Randers-Pehrson | da00980 | 2009-08-15 13:25:47 -0500 | [diff] [blame] | 427 | |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 428 | { |
| 429 | if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
| 430 | { |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 431 | if (row_info->bit_depth == 8) |
| 432 | { |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 433 | /* This inverts the alpha channel in RGBA */ |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 434 | png_bytep sp, dp; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 435 | png_uint_32 i; |
| 436 | png_uint_32 row_width = row_info->width; |
| 437 | for (i = 0, sp = dp = row; i < row_width; i++) |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 438 | { |
Glenn Randers-Pehrson | 4bb4d01 | 2009-05-20 12:45:29 -0500 | [diff] [blame] | 439 | /* Does nothing |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 440 | *(dp++) = *(sp++); |
| 441 | *(dp++) = *(sp++); |
| 442 | *(dp++) = *(sp++); |
Glenn Randers-Pehrson | 9c3ab68 | 2006-02-20 22:09:05 -0600 | [diff] [blame] | 443 | */ |
| 444 | sp+=3; dp = sp; |
Glenn Randers-Pehrson | 860ab2b | 1999-10-14 07:43:10 -0500 | [diff] [blame] | 445 | *(dp++) = (png_byte)(255 - *(sp++)); |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 446 | } |
| 447 | } |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 448 | else |
| 449 | { |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 450 | /* This inverts the alpha channel in RRGGBBAA */ |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 451 | png_bytep sp, dp; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 452 | png_uint_32 i; |
| 453 | png_uint_32 row_width = row_info->width; |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 454 | |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 455 | for (i = 0, sp = dp = row; i < row_width; i++) |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 456 | { |
Glenn Randers-Pehrson | 4bb4d01 | 2009-05-20 12:45:29 -0500 | [diff] [blame] | 457 | /* Does nothing |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 458 | *(dp++) = *(sp++); |
| 459 | *(dp++) = *(sp++); |
| 460 | *(dp++) = *(sp++); |
| 461 | *(dp++) = *(sp++); |
| 462 | *(dp++) = *(sp++); |
| 463 | *(dp++) = *(sp++); |
Glenn Randers-Pehrson | 9c3ab68 | 2006-02-20 22:09:05 -0600 | [diff] [blame] | 464 | */ |
| 465 | sp+=6; dp = sp; |
Glenn Randers-Pehrson | 860ab2b | 1999-10-14 07:43:10 -0500 | [diff] [blame] | 466 | *(dp++) = (png_byte)(255 - *(sp++)); |
| 467 | *(dp++) = (png_byte)(255 - *(sp++)); |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 468 | } |
| 469 | } |
| 470 | } |
| 471 | else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) |
| 472 | { |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 473 | if (row_info->bit_depth == 8) |
| 474 | { |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 475 | /* This inverts the alpha channel in GA */ |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 476 | png_bytep sp, dp; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 477 | png_uint_32 i; |
| 478 | png_uint_32 row_width = row_info->width; |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 479 | |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 480 | for (i = 0, sp = dp = row; i < row_width; i++) |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 481 | { |
| 482 | *(dp++) = *(sp++); |
Glenn Randers-Pehrson | 860ab2b | 1999-10-14 07:43:10 -0500 | [diff] [blame] | 483 | *(dp++) = (png_byte)(255 - *(sp++)); |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 484 | } |
| 485 | } |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 486 | else |
| 487 | { |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 488 | /* This inverts the alpha channel in GGAA */ |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 489 | png_bytep sp, dp; |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 490 | png_uint_32 i; |
| 491 | png_uint_32 row_width = row_info->width; |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 492 | |
Glenn Randers-Pehrson | 1d96361 | 1998-05-02 12:52:25 -0500 | [diff] [blame] | 493 | for (i = 0, sp = dp = row; i < row_width; i++) |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 494 | { |
Glenn Randers-Pehrson | 4bb4d01 | 2009-05-20 12:45:29 -0500 | [diff] [blame] | 495 | /* Does nothing |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 496 | *(dp++) = *(sp++); |
| 497 | *(dp++) = *(sp++); |
Glenn Randers-Pehrson | 9c3ab68 | 2006-02-20 22:09:05 -0600 | [diff] [blame] | 498 | */ |
| 499 | sp+=2; dp = sp; |
Glenn Randers-Pehrson | 860ab2b | 1999-10-14 07:43:10 -0500 | [diff] [blame] | 500 | *(dp++) = (png_byte)(255 - *(sp++)); |
| 501 | *(dp++) = (png_byte)(255 - *(sp++)); |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 502 | } |
| 503 | } |
| 504 | } |
| 505 | } |
| 506 | } |
| 507 | #endif |
Glenn Randers-Pehrson | 2ad31ae | 2000-12-15 08:54:42 -0600 | [diff] [blame] | 508 | |
Glenn Randers-Pehrson | e26c095 | 2009-09-23 11:22:08 -0500 | [diff] [blame] | 509 | #ifdef PNG_MNG_FEATURES_SUPPORTED |
Glenn Randers-Pehrson | 4bb4d01 | 2009-05-20 12:45:29 -0500 | [diff] [blame] | 510 | /* Undoes intrapixel differencing */ |
Glenn Randers-Pehrson | 2ad31ae | 2000-12-15 08:54:42 -0600 | [diff] [blame] | 511 | void /* PRIVATE */ |
| 512 | png_do_write_intrapixel(png_row_infop row_info, png_bytep row) |
| 513 | { |
Glenn Randers-Pehrson | 51650b8 | 2008-08-05 07:44:42 -0500 | [diff] [blame] | 514 | png_debug(1, "in png_do_write_intrapixel"); |
Glenn Randers-Pehrson | da00980 | 2009-08-15 13:25:47 -0500 | [diff] [blame] | 515 | |
Glenn Randers-Pehrson | 2ad31ae | 2000-12-15 08:54:42 -0600 | [diff] [blame] | 516 | if ( |
Glenn Randers-Pehrson | 2ad31ae | 2000-12-15 08:54:42 -0600 | [diff] [blame] | 517 | (row_info->color_type & PNG_COLOR_MASK_COLOR)) |
| 518 | { |
| 519 | int bytes_per_pixel; |
| 520 | png_uint_32 row_width = row_info->width; |
| 521 | if (row_info->bit_depth == 8) |
| 522 | { |
| 523 | png_bytep rp; |
| 524 | png_uint_32 i; |
| 525 | |
| 526 | if (row_info->color_type == PNG_COLOR_TYPE_RGB) |
| 527 | bytes_per_pixel = 3; |
| 528 | else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
| 529 | bytes_per_pixel = 4; |
| 530 | else |
| 531 | return; |
| 532 | |
| 533 | for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) |
| 534 | { |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 535 | *(rp) = (png_byte)((*rp - *(rp + 1)) & 0xff); |
| 536 | *(rp + 2) = (png_byte)((*(rp + 2) - *(rp + 1)) & 0xff); |
Glenn Randers-Pehrson | 2ad31ae | 2000-12-15 08:54:42 -0600 | [diff] [blame] | 537 | } |
| 538 | } |
| 539 | else if (row_info->bit_depth == 16) |
| 540 | { |
| 541 | png_bytep rp; |
| 542 | png_uint_32 i; |
| 543 | |
| 544 | if (row_info->color_type == PNG_COLOR_TYPE_RGB) |
| 545 | bytes_per_pixel = 6; |
| 546 | else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
| 547 | bytes_per_pixel = 8; |
| 548 | else |
| 549 | return; |
| 550 | |
| 551 | for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) |
| 552 | { |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 553 | png_uint_32 s0 = (*(rp ) << 8) | *(rp + 1); |
| 554 | png_uint_32 s1 = (*(rp + 2) << 8) | *(rp + 3); |
| 555 | png_uint_32 s2 = (*(rp + 4) << 8) | *(rp + 5); |
Glenn Randers-Pehrson | 145f5c8 | 2008-07-10 09:13:13 -0500 | [diff] [blame] | 556 | png_uint_32 red = (png_uint_32)((s0 - s1) & 0xffffL); |
| 557 | png_uint_32 blue = (png_uint_32)((s2 - s1) & 0xffffL); |
Glenn Randers-Pehrson | 45624d6 | 2010-03-03 11:40:43 -0600 | [diff] [blame^] | 558 | *(rp ) = (png_byte)((red >> 8) & 0xff); |
| 559 | *(rp + 1) = (png_byte)(red & 0xff); |
| 560 | *(rp + 4) = (png_byte)((blue >> 8) & 0xff); |
| 561 | *(rp + 5) = (png_byte)(blue & 0xff); |
Glenn Randers-Pehrson | 2ad31ae | 2000-12-15 08:54:42 -0600 | [diff] [blame] | 562 | } |
| 563 | } |
| 564 | } |
| 565 | } |
| 566 | #endif /* PNG_MNG_FEATURES_SUPPORTED */ |
Glenn Randers-Pehrson | 3097f61 | 2001-05-07 14:52:45 -0500 | [diff] [blame] | 567 | #endif /* PNG_WRITE_SUPPORTED */ |