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<?php
function my_handle_upload ( $params )
{
    $filePath = $params['file'];

    if ( (!is_wp_error($params)) && file_exists($filePath) && in_array($params['type'], array('image/png','image/gif','image/jpeg')))
    {
        $quality                        = 90;
        list($largeWidth, $largeHeight) = array( get_option( 'large_size_w' ), get_option( 'large_size_h' ) );
        list($oldWidth, $oldHeight)     = getimagesize( $filePath );
        list($newWidth, $newHeight)     = wp_constrain_dimensions( $oldWidth, $oldHeight, $largeWidth, $largeHeight );

        $resizeImageResult = image_resize( $filePath, $newWidth, $newHeight, false, null, null, $quality);

        unlink( $filePath );

        if ( !is_wp_error( $resizeImageResult ) )
        {
            $newFilePath = $resizeImageResult;
            rename( $newFilePath, $filePath );
        }
        else
        {
            $params = wp_handle_upload_error
            (
                $filePath,
                $resizeImageResult->get_error_message() 
            );
        }
    }

    return $params;
}
add_filter( 'wp_handle_upload', 'my_handle_upload' );