bmp-to-image-object.php — Admin and Site Enhancements (ASE) 7.6.2

admin-site-enhancements / includes / bmp-to-image-object.php

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admin-menu-width 1 year ago blank-comment-template.php 1 year ago bmp-to-image-object.php 1 year ago empty-class-classic-editor.php 1 year ago password-protected-login.php 1 year ago

bmp-to-image-object.php

189 lines

1	<?php
2
3	/**
4	* Converts BMP to JPG
5	*
6	* @link https://github.com/dompdf/dompdf/blob/master/src/Helpers.php
7	* @link http://www.programmierer-forum.de/function-imagecreatefrombmp-welche-variante-laeuft-t143137.htm
8	* @since 4.3.0
9	*/
10	function bmp_to_image_object( $filename, $context = null ) {
11	$filename = wp_kses_post( $filename );
12
13	if (!function_exists("imagecreatetruecolor")) {
14	trigger_error("The PHP GD extension is required, but is not installed.", E_ERROR);
15	return false;
16	}
17
18	// version 1.00
19	if (!($fh = fopen($filename, 'rb'))) {
20	// phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
21	trigger_error('imagecreatefrombmp: Can not open ' . $filename, E_USER_WARNING);
22	return false;
23	}
24
25	$bytes_read = 0;
26
27	// read file header
28	$meta = unpack('vtype/Vfilesize/Vreserved/Voffset', fread($fh, 14));
29
30	// check for bitmap
31	if ($meta['type'] != 19778) {
32	// phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
33	trigger_error('imagecreatefrombmp: ' . $filename . ' is not a bitmap!', E_USER_WARNING);
34	return false;
35	}
36
37	// read image header
38	$meta += unpack('Vheadersize/Vwidth/Vheight/vplanes/vbits/Vcompression/Vimagesize/Vxres/Vyres/Vcolors/Vimportant', fread($fh, 40));
39	$bytes_read += 40;
40
41	// read additional bitfield header
42	if ($meta['compression'] == 3) {
43	$meta += unpack('VrMask/VgMask/VbMask', fread($fh, 12));
44	$bytes_read += 12;
45	}
46
47	// set bytes and padding
48	$meta['bytes'] = $meta['bits'] / 8;
49	$meta['decal'] = 4 - (4 * (($meta['width'] * $meta['bytes'] / 4) - floor($meta['width'] * $meta['bytes'] / 4)));
50	if ($meta['decal'] == 4) {
51	$meta['decal'] = 0;
52	}
53
54	// obtain imagesize
55	if ($meta['imagesize'] < 1) {
56	$meta['imagesize'] = $meta['filesize'] - $meta['offset'];
57	// in rare cases filesize is equal to offset so we need to read physical size
58	if ($meta['imagesize'] < 1) {
59	$meta['imagesize'] = @filesize($filename) - $meta['offset'];
60	if ($meta['imagesize'] < 1) {
61	// phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
62	trigger_error('imagecreatefrombmp: Can not obtain filesize of ' . $filename . '!', E_USER_WARNING);
63	return false;
64	}
65	}
66	}
67
68	// calculate colors
69	$meta['colors'] = !$meta['colors'] ? pow(2, $meta['bits']) : $meta['colors'];
70
71	// read color palette
72	$palette = [];
73	if ($meta['bits'] < 16) {
74	$palette = unpack('l' . $meta['colors'], fread($fh, $meta['colors'] * 4));
75	// in rare cases the color value is signed
76	if ($palette[1] < 0) {
77	foreach ($palette as $i => $color) {
78	$palette[$i] = $color + 16777216;
79	}
80	}
81	}
82
83	// ignore extra bitmap headers
84	if ($meta['headersize'] > $bytes_read) {
85	fread($fh, $meta['headersize'] - $bytes_read);
86	}
87
88	// create gd image
89	$im = imagecreatetruecolor($meta['width'], $meta['height']);
90	$data = fread($fh, $meta['imagesize']);
91
92	// uncompress data
93	switch ($meta['compression']) {
94	case 1:
95	$data = Helpers::rle8_decode($data, $meta['width']);
96	break;
97	case 2:
98	$data = Helpers::rle4_decode($data, $meta['width']);
99	break;
100	}
101
102	$p = 0;
103	$vide = chr(0);
104	$y = $meta['height'] - 1;
105	$error = 'imagecreatefrombmp: ' . $filename . ' has not enough data!';
106
107	// loop through the image data beginning with the lower left corner
108	while ($y >= 0) {
109	$x = 0;
110	while ($x < $meta['width']) {
111	switch ($meta['bits']) {
112	case 32:
113	case 24:
114	if (!($part = substr($data, $p, 3 /$meta['bytes']/))) {
115	// phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
116	trigger_error($error, E_USER_WARNING);
117	return $im;
118	}
119	$color = unpack('V', $part . $vide);
120	break;
121	case 16:
122	if (!($part = substr($data, $p, 2 /$meta['bytes']/))) {
123	// phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
124	trigger_error($error, E_USER_WARNING);
125	return $im;
126	}
127	$color = unpack('v', $part);
128
129	if (empty($meta['rMask']) \|\| $meta['rMask'] != 0xf800) {
130	$color[1] = (($color[1] & 0x7c00) >> 7) * 65536 + (($color[1] & 0x03e0) >> 2) * 256 + (($color[1] & 0x001f) << 3); // 555
131	} else {
132	$color[1] = (($color[1] & 0xf800) >> 8) * 65536 + (($color[1] & 0x07e0) >> 3) * 256 + (($color[1] & 0x001f) << 3); // 565
133	}
134	break;
135	case 8:
136	$color = unpack('n', $vide . substr($data, $p, 1));
137	$color[1] = $palette[$color[1] + 1];
138	break;
139	case 4:
140	$color = unpack('n', $vide . substr($data, floor($p), 1));
141	$color[1] = ($p * 2) % 2 == 0 ? $color[1] >> 4 : $color[1] & 0x0F;
142	$color[1] = $palette[$color[1] + 1];
143	break;
144	case 1:
145	$color = unpack('n', $vide . substr($data, floor($p), 1));
146	switch (($p * 8) % 8) {
147	case 0:
148	$color[1] = $color[1] >> 7;
149	break;
150	case 1:
151	$color[1] = ($color[1] & 0x40) >> 6;
152	break;
153	case 2:
154	$color[1] = ($color[1] & 0x20) >> 5;
155	break;
156	case 3:
157	$color[1] = ($color[1] & 0x10) >> 4;
158	break;
159	case 4:
160	$color[1] = ($color[1] & 0x8) >> 3;
161	break;
162	case 5:
163	$color[1] = ($color[1] & 0x4) >> 2;
164	break;
165	case 6:
166	$color[1] = ($color[1] & 0x2) >> 1;
167	break;
168	case 7:
169	$color[1] = ($color[1] & 0x1);
170	break;
171	}
172	$color[1] = $palette[$color[1] + 1];
173	break;
174	default:
175	// phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
176	trigger_error('imagecreatefrombmp: ' . $filename . ' has ' . $meta['bits'] . ' bits and this is not supported!', E_USER_WARNING);
177	return false;
178	}
179	imagesetpixel($im, $x, $y, $color[1]);
180	$x++;
181	$p += $meta['bytes'];
182	}
183	$y--;
184	$p += $meta['decal'];
185	}
186	fclose($fh);
187	return $im;
188
189	}