library/Garp/Image/Scaler.php
private function _renderToImageData(&$canvas) {
        ob_start();

        switch ($this->_params['type']) {
        case IMAGETYPE_GIF:
            imagegif($canvas);
            break;
        case IMAGETYPE_JPEG:
            imagejpeg($canvas, null, $this->_params['quality']);
            break;
        case IMAGETYPE_PNG:
            // Calculate PNG quality, because it runs from 0 (uncompressed) to 9,
            // instead of 0 - 100.
            $pngQuality = ($this->_params['quality'] - 100) / 11.111111;
            $pngQuality = round(abs($pngQuality));
            imagepng($canvas, null, $pngQuality, null);
            break;
        default:
            throw new Exception('Sorry, this image type is not supported');
        }

        $imgData = ob_get_contents();
        ob_end_clean();
        return $imgData;
    }
private function _renderToImageData(&$canvas) {
        ob_start();

        switch ($this->_params['type']) {
        case IMAGETYPE_GIF:
            imagegif($canvas);
            break;
        case IMAGETYPE_JPEG:
            imagejpeg($canvas, null, $this->_params['quality']);
            break;
        case IMAGETYPE_PNG:
            // Calculate PNG quality, because it runs from 0 (uncompressed) to 9,
            // instead of 0 - 100.
            $pngQuality = ($this->_params['quality'] - 100) / 11.111111;
            $pngQuality = round(abs($pngQuality));
            imagepng($canvas, null, $pngQuality, null);
            break;
        default:
            throw new Exception('Sorry, this image type is not supported');
        }

        $imgData = ob_get_contents();
        ob_end_clean();
        return $imgData;
    }
private function _renderToImageData ( & $ canvas ) { ob_start ( ) ; switch ( $ this -> _params [ 'type' ] ) { case IMAGETYPE_GIF : imagegif ( $ canvas ) ; break ; case IMAGETYPE_JPEG : imagejpeg ( $ canvas , null , $ this -> _params [ 'quality' ] ) ; break ; case IMAGETYPE_PNG : // Calculate PNG quality, because it runs from 0 (uncompressed) to 9, // instead of 0 - 100. $ pngQuality = ( $ this -> _params [ 'quality' ] - 100 ) / 11.111111 ; $ pngQuality = round ( abs ( $ pngQuality ) ) ; imagepng ( $ canvas , null , $ pngQuality , null ) ; break ; default : throw new Exception ( 'Sorry, this image type is not supported' ) ; } $ imgData = ob_get_contents ( ) ; ob_end_clean ( ) ; return $ imgData ; }
Writes the graphical output to image file data.

@param resource  $canvas
@return resource Scaled image data
Writes the graphical output to image file data .