Total Complexity | 41 |
Total Lines | 228 |
Duplicated Lines | 0 % |
Changes | 0 |
Complex classes like BMP often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use BMP, and based on these observations, apply Extract Interface, too.
1 | <?php |
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41 | class BMP |
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42 | { |
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43 | public static function imagebmp(&$img, $filename = false) |
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103 | } |
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104 | |||
105 | public static function imagecreatefromstring($data) |
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106 | { |
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107 | //read header |
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108 | $pos = 0; |
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109 | $header = substr($data, 0, 54); |
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110 | $pos = 54; |
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111 | |||
112 | if (strlen($header) < 54) { |
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113 | return false; |
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114 | } |
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115 | |||
116 | $header = unpack( 'c2identifier/Vfile_size/Vreserved/Vbitmap_data/Vheader_size/' . |
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117 | 'Vwidth/Vheight/vplanes/vbits_per_pixel/Vcompression/Vdata_size/'. |
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118 | 'Vh_resolution/Vv_resolution/Vcolors/Vimportant_colors', $header); |
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119 | |||
120 | if ($header['identifier1'] != 66 or $header['identifier2'] != 77) { |
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121 | return false; |
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122 | } |
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123 | |||
124 | if (!in_array($header['bits_per_pixel'], array(24, 32, 8, 4, 1))) { |
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125 | return false; |
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126 | } |
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127 | |||
128 | $bps = $header['bits_per_pixel']; //bits per pixel |
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129 | $wid2 = ceil(($bps/8 * $header['width']) / 4) * 4; |
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130 | $colors = $header['colors']; |
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131 | // The absolute height value is necessary because ImageHeight can be negative |
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132 | // If Height is a positive number, then the image is a "bottom-up" bitmap with the origin in the lower-left corner. |
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133 | // If Height is a negative number, then the image is a "top-down" bitmap with the origin in the upper-left corner. |
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134 | $header['height'] = abs($header['height']); |
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135 | |||
136 | $wid = $header['width']; |
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137 | $hei = $header['height']; |
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138 | |||
139 | $img = imagecreatetruecolor($header['width'], $header['height']); |
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140 | if (!$img) { |
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141 | return false; // Invalid width or height |
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142 | } |
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143 | //read palette |
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144 | $palette = []; |
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145 | |||
146 | if ($bps < 9) { |
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147 | // A color table is mandatory for color depths <= 8 |
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148 | if (isset($header['colors']) && $header['colors'] > 0) { |
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149 | // The number of entries in the palette is either 2n |
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150 | // or a smaller number specified in the header |
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151 | $colors = min($header['colors'], $colors); |
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152 | } |
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153 | for ($i = 0; $i < $colors; $i++) { |
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154 | $palette[] = self::undword(substr($data, $pos, 4)); |
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155 | $pos += 4; |
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156 | } |
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157 | } else { |
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158 | if ($bps == 32) { |
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159 | imagealphablending($img, false); |
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160 | imagesavealpha($img, true); |
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161 | } |
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162 | |||
163 | $palette = array(); |
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164 | } |
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165 | |||
166 | //read pixels |
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167 | for ($y = $hei-1; $y >= 0; $y--) { |
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168 | $row = substr($data, $pos, $wid2); |
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169 | $pos += $wid2; |
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170 | $pixels = self::str_split2($row, $bps, $palette); |
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171 | |||
172 | for ($x = 0; $x < $wid; $x++) { |
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173 | self::makepixel($img, $x, $y, $pixels[$x], $bps); |
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174 | } |
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175 | } |
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176 | |||
177 | return $img; |
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178 | } |
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179 | |||
180 | public static function imagecreatefrombmp($filename) |
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181 | { |
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182 | return self::imagecreatefromstring(file_get_contents($filename)); |
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183 | } |
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184 | |||
185 | private static function str_split2($row, $bps, $palette) |
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186 | { |
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187 | switch ($bps) { |
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188 | case 32: |
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189 | case 24: return str_split($row, $bps / 8); |
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190 | case 8: $out = array(); |
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191 | $count = strlen($row); |
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192 | |||
193 | for ($i = 0; $i < $count; $i++) { |
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194 | $out[] = $palette[ ord($row[$i]) ]; |
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195 | } |
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196 | |||
197 | return $out; |
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198 | case 4: $out = array(); |
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199 | $count = strlen($row); |
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200 | |||
201 | for ($i = 0; $i < $count; $i++) { |
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202 | $roww = ord($row[$i]); |
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203 | $out[] = $palette[ ($roww & 240) >> 4 ]; |
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204 | $out[] = $palette[ ($roww & 15) ]; |
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205 | } |
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206 | |||
207 | return $out; |
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208 | case 1: $out = array(); |
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209 | $count = strlen($row); |
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210 | |||
211 | for ($i = 0; $i < $count; $i++) { |
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212 | $roww = ord($row[$i]); |
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213 | $out[] = $palette[ ($roww & 128) >> 7 ]; |
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214 | $out[] = $palette[ ($roww & 64) >> 6 ]; |
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215 | $out[] = $palette[ ($roww & 32) >> 5 ]; |
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216 | $out[] = $palette[ ($roww & 16) >> 4 ]; |
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217 | $out[] = $palette[ ($roww & 8) >> 3 ]; |
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218 | $out[] = $palette[ ($roww & 4) >> 2 ]; |
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219 | $out[] = $palette[ ($roww & 2) >> 1 ]; |
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220 | $out[] = $palette[ ($roww & 1) ]; |
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221 | } |
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222 | |||
223 | return $out; |
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224 | } |
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225 | } |
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226 | |||
227 | private static function makepixel($img, $x, $y, $str, $bps) |
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228 | { |
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229 | switch ($bps) { |
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230 | case 32 : $a = ord($str[0]); |
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231 | $b = ord($str[1]); |
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232 | $c = ord($str[2]); |
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233 | $d = 256 - ord($str[3]); //TODO: gives imperfect results |
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234 | $pixel = $d*256*256*256 + $c*256*256 + $b*256 + $a; |
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235 | imagesetpixel($img, $x, $y, $pixel); |
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236 | break; |
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237 | case 24 : $a = ord($str[0]); |
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238 | $b = ord($str[1]); |
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239 | $c = ord($str[2]); |
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240 | $pixel = $c*256*256 + $b*256 + $a; |
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241 | imagesetpixel($img, $x, $y, $pixel); |
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242 | break; |
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243 | case 8 : |
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244 | case 4 : |
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245 | case 1 : imagesetpixel($img, $x, $y, $str); |
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246 | break; |
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247 | } |
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248 | } |
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249 | |||
250 | private static function byte3($n) |
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251 | { |
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252 | return chr($n & 255) . chr(($n >> 8) & 255) . chr(($n >> 16) & 255); |
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253 | } |
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254 | |||
255 | private static function undword($n) |
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256 | { |
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257 | $r = unpack("V", $n); |
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258 | return $r[1]; |
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259 | } |
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260 | |||
261 | private static function dword($n) |
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262 | { |
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263 | return pack("V", $n); |
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264 | } |
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265 | |||
266 | private static function word($n) |
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269 | } |
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270 | } |
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271 |