function ApplyMask(&$image, $mask)
{
// Create copy of mask as mask may not be the same size as image
$mask_resized = ImageCreateTrueColor(ImageSX($image), ImageSY($image));
ImageCopyResampled($mask_resized, $mask, 0, 0, 0, 0, ImageSX($image), ImageSY($image), ImageSX($mask), ImageSY($mask));
// Create working temp
$mask_blendtemp = ImageCreateTrueColor(ImageSX($image), ImageSY($image));
$color_background = ImageColorAllocate($mask_blendtemp, 0, 0, 0);
ImageFilledRectangle($mask_blendtemp, 0, 0, ImageSX($mask_blendtemp), ImageSY($mask_blendtemp), $color_background);
// switch off single color alph and switch on full alpha channel
ImageAlphaBlending($mask_blendtemp, false);
ImageSaveAlpha($mask_blendtemp, true);
// loop the entire image and set pixels, this will be slow for large images
for ($x = 0; $x < ImageSX($image); $x++) {
for ($y = 0; $y < ImageSY($image); $y++) {
$RealPixel = GetPixelColor($image, $x, $y);
$MaskPixel = GrayscalePixel(GetPixelColor($mask_resized, $x, $y));
$MaskAlpha = 127 - Floor($MaskPixel['red'] / 2) * (1 - $RealPixel['alpha'] / 127);
$newcolor = ImageColorAllocateAlpha($mask_blendtemp, $RealPixel['red'], $RealPixel['green'], $RealPixel['blue'], $MaskAlpha);
ImageSetPixel($mask_blendtemp, $x, $y, $newcolor);
}
}
// don't need the mask copy anymore
ImageDestroy($mask_resized);
// switch off single color alph and switch on full alpha channel
ImageAlphaBlending($image, false);
ImageSaveAlpha($image, true);
// replace the image with the blended temp
ImageCopy($image, $mask_blendtemp, 0, 0, 0, 0, ImageSX($mask_blendtemp), ImageSY($mask_blendtemp));
ImageDestroy($mask_blendtemp);
}
function ApplyMask(&$gdimg_mask, &$gdimg_image)
{
if (gd_version() < 2) {
$DebugMessage = 'Skipping ApplyMask() because gd_version is "' . gd_version() . '"' . __FILE__ . __LINE__;
return false;
}
if (version_compare_replacement(phpversion(), '4.3.2', '>=')) {
$DebugMessage = 'Using alpha ApplyMask() technique' . __FILE__ . __LINE__;
if ($gdimg_mask_resized = ImageCreateTrueColor(ImageSX($gdimg_image), ImageSY($gdimg_image))) {
ImageCopyResampled($gdimg_mask_resized, $gdimg_mask, 0, 0, 0, 0, ImageSX($gdimg_image), ImageSY($gdimg_image), ImageSX($gdimg_mask), ImageSY($gdimg_mask));
if ($gdimg_mask_blendtemp = ImageCreateTrueColor(ImageSX($gdimg_image), ImageSY($gdimg_image))) {
$color_background = ImageColorAllocate($gdimg_mask_blendtemp, 0, 0, 0);
ImageFilledRectangle($gdimg_mask_blendtemp, 0, 0, ImageSX($gdimg_mask_blendtemp), ImageSY($gdimg_mask_blendtemp), $color_background);
ImageAlphaBlending($gdimg_mask_blendtemp, false);
ImageSaveAlpha($gdimg_mask_blendtemp, true);
for ($x = 0; $x < ImageSX($gdimg_image); $x++) {
for ($y = 0; $y < ImageSY($gdimg_image); $y++) {
//$RealPixel = phpthumb_functions::GetPixelColor($gdimg_mask_blendtemp, $x, $y);
$RealPixel = GetPixelColor($gdimg_image, $x, $y);
$MaskPixel = GrayscalePixel(GetPixelColor($gdimg_mask_resized, $x, $y));
$MaskAlpha = 127 - floor($MaskPixel['red'] / 2) * (1 - $RealPixel['alpha'] / 127);
$newcolor = ImageColorAllocateAlphaSafe($gdimg_mask_blendtemp, $RealPixel['red'], $RealPixel['green'], $RealPixel['blue'], $MaskAlpha);
ImageSetPixel($gdimg_mask_blendtemp, $x, $y, $newcolor);
}
}
ImageAlphaBlending($gdimg_image, false);
ImageSaveAlpha($gdimg_image, true);
ImageCopy($gdimg_image, $gdimg_mask_blendtemp, 0, 0, 0, 0, ImageSX($gdimg_mask_blendtemp), ImageSY($gdimg_mask_blendtemp));
ImageDestroy($gdimg_mask_blendtemp);
} else {
$DebugMessage = 'ImageCreateFunction() failed' . __FILE__ . __LINE__;
}
ImageDestroy($gdimg_mask_resized);
} else {
$DebugMessage = 'ImageCreateFunction() failed' . __FILE__ . __LINE__;
}
} else {
// alpha merging requires PHP v4.3.2+
$DebugMessage = 'Skipping ApplyMask() technique because PHP is v"' . phpversion() . '"' . __FILE__ . __LINE__;
}
return true;
}
