| 1 |
<?php |
| 2 |
|
| 3 |
namespace WebPConvert\Convert\Converters; |
| 4 |
|
| 5 |
use WebPConvert\Convert\Converters\AbstractConverter; |
| 6 |
use WebPConvert\Convert\Exceptions\ConversionFailed\ConverterNotOperational\SystemRequirementsNotMetException; |
| 7 |
use WebPConvert\Convert\Exceptions\ConversionFailed\InvalidInputException; |
| 8 |
use WebPConvert\Convert\Exceptions\ConversionFailedException; |
| 9 |
|
| 10 |
/** |
| 11 |
* Convert images to webp using gd extension. |
| 12 |
* |
| 13 |
* @package WebPConvert |
| 14 |
* @author Bjørn Rosell <[email protected]> |
| 15 |
* @since Class available since Release 2.0.0 |
| 16 |
*/ |
| 17 |
class Gd extends AbstractConverter |
| 18 |
{ |
| 19 |
public function supportsLossless() |
| 20 |
{ |
| 21 |
return false; |
| 22 |
} |
| 23 |
|
| 24 |
protected function getUnsupportedDefaultOptions() |
| 25 |
{ |
| 26 |
return [ |
| 27 |
'alpha-quality', |
| 28 |
'auto-filter', |
| 29 |
'encoding', |
| 30 |
'low-memory', |
| 31 |
'metadata', |
| 32 |
'method', |
| 33 |
'near-lossless', |
| 34 |
'preset', |
| 35 |
'sharp-yuv', |
| 36 |
'size-in-percentage', |
| 37 |
]; |
| 38 |
} |
| 39 |
|
| 40 |
private $errorMessageWhileCreating = ''; |
| 41 |
private $errorNumberWhileCreating; |
| 42 |
|
| 43 |
/** |
| 44 |
* Check (general) operationality of Gd converter. |
| 45 |
* |
| 46 |
* @throws SystemRequirementsNotMetException if system requirements are not met |
| 47 |
*/ |
| 48 |
public function checkOperationality() |
| 49 |
{ |
| 50 |
if (!extension_loaded('gd')) { |
| 51 |
throw new SystemRequirementsNotMetException('Required Gd extension is not available.'); |
| 52 |
} |
| 53 |
|
| 54 |
if (!function_exists('imagewebp')) { |
| 55 |
throw new SystemRequirementsNotMetException( |
| 56 |
'Gd has been compiled without webp support.' |
| 57 |
); |
| 58 |
} |
| 59 |
|
| 60 |
if (!function_exists('imagepalettetotruecolor')) { |
| 61 |
if (!self::functionsExist([ |
| 62 |
'imagecreatetruecolor', 'imagealphablending', 'imagecolorallocatealpha', |
| 63 |
'imagefilledrectangle', 'imagecopy', 'imagedestroy', 'imagesx', 'imagesy' |
| 64 |
])) { |
| 65 |
throw new SystemRequirementsNotMetException( |
| 66 |
'Gd cannot convert palette color images to RGB. ' . |
| 67 |
'Even though it would be possible to convert RGB images to webp with Gd, ' . |
| 68 |
'we refuse to do it. A partial working converter causes more trouble than ' . |
| 69 |
'a non-working. To make this converter work, you need the imagepalettetotruecolor() ' . |
| 70 |
'function to be enabled on your system.' |
| 71 |
); |
| 72 |
} |
| 73 |
} |
| 74 |
} |
| 75 |
|
| 76 |
/** |
| 77 |
* Check if specific file is convertable with current converter / converter settings. |
| 78 |
* |
| 79 |
* @throws SystemRequirementsNotMetException if Gd has been compiled without support for image type |
| 80 |
*/ |
| 81 |
public function checkConvertability() |
| 82 |
{ |
| 83 |
$mimeType = $this->getMimeTypeOfSource(); |
| 84 |
switch ($mimeType) { |
| 85 |
case 'image/png': |
| 86 |
if (!function_exists('imagecreatefrompng')) { |
| 87 |
throw new SystemRequirementsNotMetException( |
| 88 |
'Gd has been compiled without PNG support and can therefore not convert this PNG image.' |
| 89 |
); |
| 90 |
} |
| 91 |
break; |
| 92 |
|
| 93 |
case 'image/jpeg': |
| 94 |
if (!function_exists('imagecreatefromjpeg')) { |
| 95 |
throw new SystemRequirementsNotMetException( |
| 96 |
'Gd has been compiled without Jpeg support and can therefore not convert this jpeg image.' |
| 97 |
); |
| 98 |
} |
| 99 |
} |
| 100 |
} |
| 101 |
|
| 102 |
/** |
| 103 |
* Find out if all functions exists. |
| 104 |
* |
| 105 |
* @return boolean |
| 106 |
*/ |
| 107 |
private static function functionsExist($functionNamesArr) |
| 108 |
{ |
| 109 |
foreach ($functionNamesArr as $functionName) { |
| 110 |
if (!function_exists($functionName)) { |
| 111 |
return false; |
| 112 |
} |
| 113 |
} |
| 114 |
return true; |
| 115 |
} |
| 116 |
|
| 117 |
/** |
| 118 |
* Try to convert image pallette to true color on older systems that does not have imagepalettetotruecolor(). |
| 119 |
* |
| 120 |
* The aim is to function as imagepalettetotruecolor, but for older systems. |
| 121 |
* So, if the image is already rgb, nothing will be done, and true will be returned |
| 122 |
* PS: Got the workaround here: https://secure.php.net/manual/en/function.imagepalettetotruecolor.php |
| 123 |
* |
| 124 |
* @param resource|\GdImage $image |
| 125 |
* @return boolean TRUE if the convertion was complete, or if the source image already is a true color image, |
| 126 |
* otherwise FALSE is returned. |
| 127 |
*/ |
| 128 |
private function makeTrueColorUsingWorkaround(&$image) |
| 129 |
{ |
| 130 |
//return $this->makeTrueColor($image); |
| 131 |
/* |
| 132 |
if (function_exists('imageistruecolor') && imageistruecolor($image)) { |
| 133 |
return true; |
| 134 |
}*/ |
| 135 |
if (self::functionsExist(['imagecreatetruecolor', 'imagealphablending', 'imagecolorallocatealpha', |
| 136 |
'imagefilledrectangle', 'imagecopy', 'imagedestroy', 'imagesx', 'imagesy'])) { |
| 137 |
$dst = imagecreatetruecolor(imagesx($image), imagesy($image)); |
| 138 |
|
| 139 |
if ($dst === false) { |
| 140 |
return false; |
| 141 |
} |
| 142 |
|
| 143 |
$success = false; |
| 144 |
|
| 145 |
//prevent blending with default black |
| 146 |
if (imagealphablending($dst, false) !== false) { |
| 147 |
//change the RGB values if you need, but leave alpha at 127 |
| 148 |
$transparent = imagecolorallocatealpha($dst, 255, 255, 255, 127); |
| 149 |
|
| 150 |
if ($transparent !== false) { |
| 151 |
//simpler than flood fill |
| 152 |
if (imagefilledrectangle($dst, 0, 0, imagesx($image), imagesy($image), $transparent) !== false) { |
| 153 |
//restore default blending |
| 154 |
if (imagealphablending($dst, true) !== false) { |
| 155 |
if (imagecopy($dst, $image, 0, 0, 0, 0, imagesx($image), imagesy($image)) !== false) { |
| 156 |
$success = true; |
| 157 |
} |
| 158 |
}; |
| 159 |
} |
| 160 |
} |
| 161 |
} |
| 162 |
if ($success) { |
| 163 |
imagedestroy($image); |
| 164 |
$image = $dst; |
| 165 |
} else { |
| 166 |
imagedestroy($dst); |
| 167 |
} |
| 168 |
return $success; |
| 169 |
} else { |
| 170 |
// The necessary methods for converting color palette are not avalaible |
| 171 |
return false; |
| 172 |
} |
| 173 |
} |
| 174 |
|
| 175 |
/** |
| 176 |
* Try to convert image pallette to true color. |
| 177 |
* |
| 178 |
* Try to convert image pallette to true color. If imagepalettetotruecolor() exists, that is used (available from |
| 179 |
* PHP >= 5.5.0). Otherwise using workaround found on the net. |
| 180 |
* |
| 181 |
* @param resource|\GdImage $image |
| 182 |
* @return boolean TRUE if the convertion was complete, or if the source image already is a true color image, |
| 183 |
* otherwise FALSE is returned. |
| 184 |
*/ |
| 185 |
private function makeTrueColor(&$image) |
| 186 |
{ |
| 187 |
if (function_exists('imagepalettetotruecolor')) { |
| 188 |
return imagepalettetotruecolor($image); |
| 189 |
} else { |
| 190 |
$this->logLn( |
| 191 |
'imagepalettetotruecolor() is not available on this system - using custom implementation instead' |
| 192 |
); |
| 193 |
return $this->makeTrueColorUsingWorkaround($image); |
| 194 |
} |
| 195 |
} |
| 196 |
|
| 197 |
/** |
| 198 |
* Create Gd image resource from source |
| 199 |
* |
| 200 |
* @throws InvalidInputException if mime type is unsupported or could not be detected |
| 201 |
* @throws ConversionFailedException if imagecreatefrompng or imagecreatefromjpeg fails |
| 202 |
* @return resource|\GdImage $image The created image |
| 203 |
*/ |
| 204 |
private function createImageResource() |
| 205 |
{ |
| 206 |
$mimeType = $this->getMimeTypeOfSource(); |
| 207 |
|
| 208 |
switch ($mimeType) { |
| 209 |
case 'image/png': |
| 210 |
$image = imagecreatefrompng($this->source); |
| 211 |
if ($image === false) { |
| 212 |
throw new ConversionFailedException( |
| 213 |
'Gd failed when trying to load/create image (imagecreatefrompng() failed)' |
| 214 |
); |
| 215 |
} |
| 216 |
return $image; |
| 217 |
|
| 218 |
case 'image/jpeg': |
| 219 |
$image = imagecreatefromjpeg($this->source); |
| 220 |
if ($image === false) { |
| 221 |
throw new ConversionFailedException( |
| 222 |
'Gd failed when trying to load/create image (imagecreatefromjpeg() failed)' |
| 223 |
); |
| 224 |
} |
| 225 |
return $image; |
| 226 |
} |
| 227 |
|
| 228 |
throw new InvalidInputException('Unsupported mime type'); |
| 229 |
} |
| 230 |
|
| 231 |
/** |
| 232 |
* Try to make image resource true color if it is not already. |
| 233 |
* |
| 234 |
* @param resource|\GdImage $image The image to work on |
| 235 |
* @return boolean|null True if it is now true color. False if it is NOT true color. null, if we cannot tell |
| 236 |
*/ |
| 237 |
protected function tryToMakeTrueColorIfNot(&$image) |
| 238 |
{ |
| 239 |
$whatIsItNow = null; |
| 240 |
$mustMakeTrueColor = false; |
| 241 |
if (function_exists('imageistruecolor')) { |
| 242 |
if (imageistruecolor($image)) { |
| 243 |
$this->logLn('image is true color'); |
| 244 |
$whatIsItNow = true; |
| 245 |
} else { |
| 246 |
$this->logLn('image is not true color'); |
| 247 |
$mustMakeTrueColor = true; |
| 248 |
$whatIsItNow = false; |
| 249 |
} |
| 250 |
} else { |
| 251 |
$this->logLn('It can not be determined if image is true color'); |
| 252 |
$mustMakeTrueColor = true; |
| 253 |
} |
| 254 |
|
| 255 |
if ($mustMakeTrueColor) { |
| 256 |
$this->logLn('converting color palette to true color'); |
| 257 |
$success = $this->makeTrueColor($image); |
| 258 |
if ($success) { |
| 259 |
return true; |
| 260 |
} else { |
| 261 |
$this->logLn( |
| 262 |
'FAILED converting color palette to true color. ' |
| 263 |
); |
| 264 |
} |
| 265 |
} |
| 266 |
return $whatIsItNow; |
| 267 |
} |
| 268 |
|
| 269 |
/** |
| 270 |
* |
| 271 |
* @param resource|\GdImage $image |
| 272 |
* @return boolean true if alpha blending was set successfully, false otherwise |
| 273 |
*/ |
| 274 |
protected function trySettingAlphaBlending($image) |
| 275 |
{ |
| 276 |
if (function_exists('imagealphablending')) { |
| 277 |
// TODO: Should we set second parameter to false instead? |
| 278 |
// As here: https://www.texelate.co.uk/blog/retaining-png-transparency-with-php-gd |
| 279 |
// (PS: I have backed up some local changes - to Gd.php, which includes changing that param |
| 280 |
// to false. But I didn't finish up back then and now I forgot, so need to retest before |
| 281 |
// changing anything... |
| 282 |
if (!imagealphablending($image, true)) { |
| 283 |
$this->logLn('Warning: imagealphablending() failed'); |
| 284 |
return false; |
| 285 |
} |
| 286 |
} else { |
| 287 |
$this->logLn( |
| 288 |
'Warning: imagealphablending() is not available on your system.' . |
| 289 |
' Converting PNGs with transparency might fail on some systems' |
| 290 |
); |
| 291 |
return false; |
| 292 |
} |
| 293 |
|
| 294 |
if (function_exists('imagesavealpha')) { |
| 295 |
if (!imagesavealpha($image, true)) { |
| 296 |
$this->logLn('Warning: imagesavealpha() failed'); |
| 297 |
return false; |
| 298 |
} |
| 299 |
} else { |
| 300 |
$this->logLn( |
| 301 |
'Warning: imagesavealpha() is not available on your system. ' . |
| 302 |
'Converting PNGs with transparency might fail on some systems' |
| 303 |
); |
| 304 |
return false; |
| 305 |
} |
| 306 |
return true; |
| 307 |
} |
| 308 |
|
| 309 |
protected function errorHandlerWhileCreatingWebP($errno, $errstr, $errfile, $errline) |
| 310 |
{ |
| 311 |
$this->errorNumberWhileCreating = $errno; |
| 312 |
$this->errorMessageWhileCreating = $errstr . ' in ' . $errfile . ', line ' . $errline . |
| 313 |
', PHP ' . PHP_VERSION . ' (' . PHP_OS . ')'; |
| 314 |
//return false; |
| 315 |
} |
| 316 |
|
| 317 |
/** |
| 318 |
* |
| 319 |
* @param resource|\GdImage $image |
| 320 |
* @return void |
| 321 |
*/ |
| 322 |
protected function destroyAndRemove($image) |
| 323 |
{ |
| 324 |
imagedestroy($image); |
| 325 |
if (file_exists($this->destination)) { |
| 326 |
unlink($this->destination); |
| 327 |
} |
| 328 |
} |
| 329 |
|
| 330 |
/** |
| 331 |
* |
| 332 |
* @param resource|\GdImage $image |
| 333 |
* @return void |
| 334 |
*/ |
| 335 |
protected function tryConverting($image) |
| 336 |
{ |
| 337 |
|
| 338 |
// Danger zone! |
| 339 |
// Using output buffering to generate image. |
| 340 |
// In this zone, Do NOT do anything that might produce unwanted output |
| 341 |
// Do NOT call $this->logLn |
| 342 |
// --------------------------------- (start of danger zone) |
| 343 |
|
| 344 |
$addedZeroPadding = false; |
| 345 |
set_error_handler(array($this, "errorHandlerWhileCreatingWebP")); |
| 346 |
|
| 347 |
// This line may trigger log, so we need to do it BEFORE ob_start() ! |
| 348 |
$q = $this->getCalculatedQuality(); |
| 349 |
|
| 350 |
ob_start(); |
| 351 |
|
| 352 |
// Adding this try/catch is perhaps not neccessary. |
| 353 |
// I'm not certain that the error handler takes care of Throwable errors. |
| 354 |
// and - sorry - was to lazy to find out right now. So for now: better safe than sorry. #320 |
| 355 |
$error = null; |
| 356 |
$success = false; |
| 357 |
|
| 358 |
try { |
| 359 |
// Beware: This call can throw FATAL on windows (cannot be catched) |
| 360 |
// This for example happens on palette images |
| 361 |
$success = imagewebp($image, null, $q); |
| 362 |
} catch (\Exception $e) { |
| 363 |
$error = $e; |
| 364 |
} catch (\Throwable $e) { |
| 365 |
$error = $e; |
| 366 |
} |
| 367 |
if (!is_null($error)) { |
| 368 |
restore_error_handler(); |
| 369 |
ob_end_clean(); |
| 370 |
$this->destroyAndRemove($image); |
| 371 |
throw $error; |
| 372 |
} |
| 373 |
if (!$success) { |
| 374 |
$this->destroyAndRemove($image); |
| 375 |
ob_end_clean(); |
| 376 |
restore_error_handler(); |
| 377 |
throw new ConversionFailedException( |
| 378 |
'Failed creating image. Call to imagewebp() failed.', |
| 379 |
$this->errorMessageWhileCreating |
| 380 |
); |
| 381 |
} |
| 382 |
|
| 383 |
|
| 384 |
// The following hack solves an `imagewebp` bug |
| 385 |
// See https://stackoverflow.com/questions/30078090/imagewebp-php-creates-corrupted-webp-files |
| 386 |
if (ob_get_length() % 2 == 1) { |
| 387 |
echo "\0"; |
| 388 |
$addedZeroPadding = true; |
| 389 |
} |
| 390 |
$output = ob_get_clean(); |
| 391 |
restore_error_handler(); |
| 392 |
|
| 393 |
if ($output == '') { |
| 394 |
$this->destroyAndRemove($image); |
| 395 |
throw new ConversionFailedException( |
| 396 |
'Gd failed: imagewebp() returned empty string' |
| 397 |
); |
| 398 |
} |
| 399 |
|
| 400 |
// --------------------------------- (end of danger zone). |
| 401 |
|
| 402 |
|
| 403 |
if ($this->errorMessageWhileCreating != '') { |
| 404 |
switch ($this->errorNumberWhileCreating) { |
| 405 |
case E_WARNING: |
| 406 |
$this->logLn('An warning was produced during conversion: ' . $this->errorMessageWhileCreating); |
| 407 |
break; |
| 408 |
case E_NOTICE: |
| 409 |
$this->logLn('An notice was produced during conversion: ' . $this->errorMessageWhileCreating); |
| 410 |
break; |
| 411 |
default: |
| 412 |
$this->destroyAndRemove($image); |
| 413 |
throw new ConversionFailedException( |
| 414 |
'An error was produced during conversion', |
| 415 |
$this->errorMessageWhileCreating |
| 416 |
); |
| 417 |
//break; |
| 418 |
} |
| 419 |
} |
| 420 |
|
| 421 |
if ($addedZeroPadding) { |
| 422 |
$this->logLn( |
| 423 |
'Fixing corrupt webp by adding a zero byte ' . |
| 424 |
'(older versions of Gd had a bug, but this hack fixes it)' |
| 425 |
); |
| 426 |
} |
| 427 |
|
| 428 |
$success = file_put_contents($this->destination, $output); |
| 429 |
|
| 430 |
if (!$success) { |
| 431 |
$this->destroyAndRemove($image); |
| 432 |
throw new ConversionFailedException( |
| 433 |
'Gd failed when trying to save the image. Check file permissions!' |
| 434 |
); |
| 435 |
} |
| 436 |
|
| 437 |
/* |
| 438 |
Previous code was much simpler, but on a system, the hack was not activated (a file with uneven number of bytes |
| 439 |
was created). This is puzzeling. And the old code did not provide any insights. |
| 440 |
Also, perhaps having two subsequent writes to the same file could perhaps cause a problem. |
| 441 |
In the new code, there is only one write. |
| 442 |
However, a bad thing about the new code is that the entire webp file is read into memory. This might cause |
| 443 |
memory overflow with big files. |
| 444 |
Perhaps we should check the filesize of the original and only use the new code when it is smaller than |
| 445 |
memory limit set in PHP by a certain factor. |
| 446 |
Or perhaps only use the new code on older versions of Gd |
| 447 |
https://wordpress.org/support/topic/images-not-seen-on-chrome/#post-11390284 |
| 448 |
|
| 449 |
Here is the old code: |
| 450 |
|
| 451 |
$success = imagewebp($image, $this->destination, $this->getCalculatedQuality()); |
| 452 |
|
| 453 |
if (!$success) { |
| 454 |
throw new ConversionFailedException( |
| 455 |
'Gd failed when trying to save the image as webp (call to imagewebp() failed). ' . |
| 456 |
'It probably failed writing file. Check file permissions!' |
| 457 |
); |
| 458 |
} |
| 459 |
|
| 460 |
|
| 461 |
// This hack solves an `imagewebp` bug |
| 462 |
// See https://stackoverflow.com/questions/30078090/imagewebp-php-creates-corrupted-webp-files |
| 463 |
if (filesize($this->destination) % 2 == 1) { |
| 464 |
file_put_contents($this->destination, "\0", FILE_APPEND); |
| 465 |
} |
| 466 |
*/ |
| 467 |
} |
| 468 |
|
| 469 |
// Although this method is public, do not call directly. |
| 470 |
// You should rather call the static convert() function, defined in AbstractConverter, which |
| 471 |
// takes care of preparing stuff before calling doConvert, and validating after. |
| 472 |
protected function doActualConvert() |
| 473 |
{ |
| 474 |
$versionString = gd_info()["GD Version"]; |
| 475 |
$this->logLn('GD Version: ' . $versionString); |
| 476 |
|
| 477 |
// Btw: Check out processWebp here: |
| 478 |
// https://github.com/Intervention/image/blob/master/src/Intervention/Image/Gd/Encoder.php |
| 479 |
|
| 480 |
// Create image resource |
| 481 |
$image = $this->createImageResource(); |
| 482 |
|
| 483 |
// Try to convert color palette if it is not true color |
| 484 |
$isItTrueColorNow = $this->tryToMakeTrueColorIfNot($image); |
| 485 |
if ($isItTrueColorNow === false) { |
| 486 |
// our tests shows that converting palette fails on all systems, |
| 487 |
throw new ConversionFailedException( |
| 488 |
'Cannot convert image because it is a palette image and the palette image cannot ' . |
| 489 |
'be converted to RGB (which is required). To convert to RGB, we would need ' . |
| 490 |
'imagepalettetotruecolor(), which is not available on your system. ' . |
| 491 |
'Our workaround does not have the neccasary functions for converting to RGB either.' |
| 492 |
); |
| 493 |
} |
| 494 |
if (is_null($isItTrueColorNow)) { |
| 495 |
$isWindows = preg_match('/^win/i', PHP_OS); |
| 496 |
$isMacDarwin = preg_match('/^darwin/i', PHP_OS); // actually no problem in PHP 7.4 and 8.0 |
| 497 |
if ($isWindows || $isMacDarwin) { |
| 498 |
throw new ConversionFailedException( |
| 499 |
'Cannot convert image because it appears to be a palette image and the palette image ' . |
| 500 |
'cannot be converted to RGB, as you do not have imagepalettetotruecolor() enabled. ' . |
| 501 |
'Converting palette on ' . |
| 502 |
($isWindows ? 'Windows causes FATAL error' : 'Mac causes halt') . |
| 503 |
'So we abort now' |
| 504 |
); |
| 505 |
} |
| 506 |
} |
| 507 |
|
| 508 |
if ($this->getMimeTypeOfSource() == 'image/png') { |
| 509 |
if (function_exists('version_compare')) { |
| 510 |
if (version_compare($versionString, "2.1.1", "<=")) { |
| 511 |
$this->logLn( |
| 512 |
'BEWARE: Your version of Gd looses the alpha chanel when converting to webp.' . |
| 513 |
'You should upgrade Gd, use another converter or stop converting PNGs. ' . |
| 514 |
'See: https://github.com/rosell-dk/webp-convert/issues/238' |
| 515 |
); |
| 516 |
} elseif (version_compare($versionString, "2.2.4", "<=")) { |
| 517 |
$this->logLn( |
| 518 |
'BEWARE: Older versions of Gd looses the alpha chanel when converting to webp.' . |
| 519 |
'We have not tested if transparency fails on your (rather old) version of Gd. ' . |
| 520 |
'Please let us know. ' . |
| 521 |
'See: https://github.com/rosell-dk/webp-convert/issues/238' |
| 522 |
); |
| 523 |
} |
| 524 |
} |
| 525 |
|
| 526 |
// Try to set alpha blending |
| 527 |
$this->trySettingAlphaBlending($image); |
| 528 |
} |
| 529 |
|
| 530 |
// Try to convert it to webp |
| 531 |
$this->tryConverting($image); |
| 532 |
|
| 533 |
// End of story |
| 534 |
imagedestroy($image); |
| 535 |
} |
| 536 |
} |
| 537 |
|
