Crop the image if dimensions are known

Question

I have an image and all the required dimensions for cropping the image.I want to pick the image from source path and save the image to destination path.I want to know which functions in PHP should i use to crop the image and save it.

Start by looking at the PHP manual: http://ca.php.net/manual/en/book.imagick.php — rink.attendant.6, May 23 '13 at 05:23
This might be helpful: http://stackoverflow.com/questions/1855996/crop-image-in-php — Teodor Talov, May 23 '13 at 05:24

score 3 · Answer 1 · answered May 23 '13 at 05:28

The follwing code will do the work

/**
 * Php function to crop an image
 * 
 * @param string $source_image Path of the source image
 * @param string $target_image Path of the target image
 * @param array $crop_area Array like array('left' => [LEFT], 'top' => [TOP],
 *                                          'width' => [WIDTH], => 'height' => [HEIGHT]) 
 */
function cropImage($source_image, $target_image, $crop_area)
{
    // detect source image type from extension
    $source_file_name = basename($source_image);
    $source_image_type = substr($source_file_name, -3, 3);

    // create an image resource from the source image  
    switch(strtolower($source_image_type))
    {
        case 'jpg':
            $original_image = imagecreatefromjpeg($source_image);
            break;

        case 'gif':
            $original_image = imagecreatefromgif($source_image);
            break;

        case 'png':
            $original_image = imagecreatefrompng($source_image);
            break;    

        default:
            trigger_error('cropImage(): Invalid source image type', E_USER_ERROR);
            return false;
    }

    // create a blank image having the same width and height as the crop area
    // this will be our cropped image
    $cropped_image = imagecreatetruecolor($crop_area['width'], $crop_area['height']);

    // copy the crop area from the source image to the blank image created above
    imagecopy($cropped_image, $original_image, 0, 0, $crop_area['left'], $crop_area['top'], 
              $crop_area['width'], $crop_area['height']);

    // detect target image type from extension
    $target_file_name = basename($target_image);
    $target_image_type = substr($target_file_name, -3, 3);

    // save the cropped image to disk
    switch(strtolower($target_image_type))
    {
        case 'jpg':
            imagejpeg($cropped_image, $target_image, 100);
            break;

        case 'gif':
            imagegif($cropped_image, $target_image);
            break;

        case 'png':
            imagepng($cropped_image, $target_image, 0);
            break;    

        default:
            trigger_error('cropImage(): Invalid target image type', E_USER_ERROR);
            imagedestroy($cropped_image);
            imagedestroy($original_image);
            return false;
    }

    // free resources
    imagedestroy($cropped_image);
    imagedestroy($original_image);

    return true;
}


// using the function to crop an image
$source_image = 'image.jpg';
$target_image = 'cropped_image.jpg';
$crop_area = array('top' => 100, 'left' => 100, 'height' => 300, 'width' => 300);

cropImage($source_image, $target_image, $crop_area);

OR See this

score 1 · Answer 2 · edited May 23 '13 at 07:56

Try this function, it generates a new image in the dimensions you specify, maintaining the aspect ratio and croping image when necessary.

function resize_image_crop($image, $width, $height)
 {

    $w = @imagesx($image); //current width

    $h = @imagesy($image); //current height
    if ((!$w) || (!$h)) { $GLOBALS['errors'][] = 'Image couldn\'t be resized because it wasn\'t a valid image.'; return false; }
    if (($w == $width) && ($h == $height)) { return $image; }  //no resizing needed
    $ratio = $width / $w;       //try max width first...
    $new_w = $width;
    $new_h = $h * $ratio;    
    if ($new_h < $height) {  //if that created an image smaller than what we wanted, try the other way
        $ratio = $height / $h;
        $new_h = $height;
        $new_w = $w * $ratio;
    }
    $image2 = imagecreatetruecolor ($new_w, $new_h);
    imagecopyresampled($image2,$image, 0, 0, 0, 0, $new_w, $new_h, $w, $h);    
    if (($new_h != $height) || ($new_w != $width)) {    //check to see if cropping needs to happen
        $image3 = imagecreatetruecolor ($width, $height);
        if ($new_h > $height) { //crop vertically
            $extra = $new_h - $height;
            $x = 0; //source x
            $y = round($extra / 2); //source y
            imagecopyresampled($image3,$image2, 0, 0, $x, $y, $width, $height, $width, $height);
        } else {
            $extra = $new_w - $width;
            $x = round($extra / 2); //source x
            $y = 0; //source y
            imagecopyresampled($image3,$image2, 0, 0, $x, $y, $width, $height, $width, $height);
        }
        imagedestroy($image2);
        return $image3;
    } else {
        return $image2;
    }
}

Crop the image if dimensions are known

2 Answers2