Detect main colors in an image with PHP

Question

I am trying to replicate the functionality that Dribbble.com does with detecting the predominant colors in an Image. In the image below you can see a screenshot from Dribbb

Answer 1

You need to scale down the picture and you will get the main colors of the picture. If you need 4 colors in the pallet, scale it down to about 8x8, 6 colors to about 12x8 and so on...

imagecopyresized for scaled down image then check every pixels and store them in array imagecolorat($image,px,py)

Try this out

$val)
        echo '
 
';
}

function getColorPallet($imageURL, $palletSize=[16,8]){ // GET PALLET FROM IMAGE PLAY WITH INPUT PALLET SIZE
    // SIMPLE CHECK INPUT VALUES
    if(!$imageURL) return false;

    // IN THIS EXEMPLE WE CREATE PALLET FROM JPG IMAGE
    $img = imagecreatefromjpeg($imageURL);

    // SCALE DOWN IMAGE
    $imgSizes=getimagesize($imageURL);

    $resizedImg=imagecreatetruecolor($palletSize[0],$palletSize[1]);

    imagecopyresized($resizedImg, $img , 0, 0 , 0, 0, $palletSize[0], $palletSize[1], $imgSizes[0], $imgSizes[1]);

    imagedestroy($img);

    //CHECK IMAGE
    /*header("Content-type: image/png");
    imagepng($resizedImg);
    die();*/

    //GET COLORS IN ARRAY
    $colors=[];

    for($i=0;$i<$palletSize[1];$i++)
        for($j=0;$j<$palletSize[0];$j++)
            $colors[]=dechex(imagecolorat($resizedImg,$j,$i));

    imagedestroy($resizedImg);

    //REMOVE DUPLICATES
    $colors= array_unique($colors);

    return $colors;

}
?>

Works perfect for me.