Php - replace base color of transparent png image

Question

I have searched a lot and I found only few solutions (on google and stackoverflow so please don\'t mark this one as a duplicate unless there\'s really duplicate question), b

Answer 1

Using SteAp's accepted code as a starting point (since with it i didnt manage to achieve transparency, just a white background), i adapted said code and the result is this:

" );
                $flagOK = 0; 
            } else if ($flagFoundColor) {
                imagesetpixel( $im_dst, $x, $y, $colorNew );
                //echo "x:$x y:$y col=$colorNew alpha:$alpha
";
            } 
        }
    }
    $flagOK2 = imagepng($im_dst, $outputFilePathIn);

    if ($flagOK && $flagOK2) {
        echo ("Congratulations, your conversion was successful 
new file $outputFilePathIn
");
    } else if ($flagOK2 && !$flagOK) {
        echo ("ERROR, your conversion was UNsuccessful
Please verify if your PNG is truecolor
input file $inputFilePathIn
");
    } else if (!$flagOK2 && $flagOK) {
        $dirNameOutput = dirname($outputFilePathIn)."/";
        echo ("ERROR, your conversion was successful, but could not save file
Please verify that you have PERMISSION to save to directory $dirName 
input file $inputFilePathIn
");
    } else {
        $dirNameOutput = dirname($outputFilePathIn)."/";
        echo ("ERROR, your conversion was UNsuccessful AND could not save file
Please verify if your PNG is truecolor
Please verify that you have PERMISSION to save to directory $dirName 
input file $inputFilePathIn
");
    }

    echo ("TargetName:$outputFilePathIn wid:$width height:$height CONVERTED:|$flagOK| SAVED:|$flagOK2|
");
    imagedestroy($im_dst);
    imagedestroy($im_src);
}




$targetRed = 0;
$targetGreen = 180;
$targetBlue = 0;

//$inputFileName = 'frameSquareBlack_88x110.png';
$inputFileName = 'testMe.png';
$dirName = "../img/profilePics/";
$nameTemp = basename($inputFileName, ".png");
$outputFileName = $nameTemp."_$targetRed"."_$targetGreen"."_$targetBlue.png";
$inputFilePath = $dirName.$inputFileName;
$outputFilePath = $dirName.$outputFileName;

//echo "inputFileName:$inputFilePath
outputName:$outputFilePath
";
colorizeKeepAplhaChannnel( $inputFilePath, $targetRed, $targetGreen, $targetBlue, $outputFilePath);
?>



Original 




Colorized

this variation changes ALL colors to chosen color (not just black, a simple IF can solve the problem - uncomment 3 indicated lines in function and you will achieve this)

For illustrative purposes, in this case, the following image was used (because leaf.png is monochromatic, with transparency):