imagecopy - PHP code example

How to Use the PHP Function Imagecopy

PHP has many built-in functions that allow you to perform a wide range of common programming tasks effortlessly. One of these is imagecopy, which allows you to copy a rectangular area from one image to another. To use this function, simply pass the parameters dst_image, src_image, x_coordinate, y_coordinate, width, height and the rectangle you want to copy. The function will then take care of the rest.

This function can be used in combination with other image processing functions such as imagecopymerge. The difference between the two is that imagecopy() always overwrites the destination image pixels with those of the source, while imagecopymerge() allows you to control how much of the destination pixels are copied over by using the last parameter (e.g. 0 means keep the destination pixels completely separate, 100 overwrites them fully with those of the source).

To use this function, you must have the GD library activated on your server/host and be running PHP version 5.4 or above. The GD library is the most popular image-processing tool for PHP, allowing dynamic creation and editing of various file formats including GIF, JPEG, PNG, TIFF and WBMP images. You can check if GD is activated by running ?php phpinfo();?>.

There are a number of different ways to output an image in PHP, but the most common method is to call the header() function and then use the readfile() function to read the file and send its contents to the browser. To get the most out of this functionality, you should always call header() before calling readfile() to make sure that all of the image processing and output is done before the file is sent to the browser.

imagecopy example

function _crop_image_resource( $img, $x, $y, $w, $h ) {
    $dst = wp_imagecreatetruecolor( $w, $h );

    if ( is_gd_image( $dst ) ) {
        if ( imagecopy( $dst, $img, 0, 0, $x, $y, $w, $h ) ) {
            imagedestroy( $img );
            $img = $dst;
        }
    }

    return $img;
}

/** * Performs group of changes on Editor specified. * * @since 2.9.0 * * @param WP_Image_Editor $image WP_Image_Editor instance. * @param array $changes Array of change operations. * @return WP_Image_Editor WP_Image_Editor instance with changes applied. */

// Convert indexed images to truecolor, copying the image to a new       // truecolor resource, so that filters work correctly and don't result       // in unnecessary dither.       $data = [
        'width' => imagesx($resource),
        'height' => imagesy($resource),
        'extension' => image_type_to_extension($this->getType(), FALSE),
        'transparent_color' => $this->getTransparentColor(),
        'is_temp' => TRUE,
      ];
      if ($this->apply('create_new', $data)) {
        imagecopy($this->getResource(), $resource, 0, 0, 0, 0, imagesx($resource), imagesy($resource));
        imagedestroy($resource);
      }
    }
    return (bool) $this->getResource();
  }

  /** * {@inheritdoc} */
  public function isValid() {
    return ((bool) $this->preLoadInfo || (bool) $this->resource);
  }

$create = 'imagecreatetruecolor';
            $copy   = 'imagecopyresampled';
        } else {
            $create = 'imagecreate';
            $copy   = 'imagecopyresized';
        }
        $dest = $create($this->width, $this->height);

        $matte = imagecolorallocate($dest, $red, $green, $blue);

        imagefilledrectangle($dest, 0, 0, $this->width, $this->height, $matte);
        imagecopy($dest, $srcImg, 0, 0, 0, 0, $this->width, $this->height);

        // Kill the file handles         imagedestroy($srcImg);

        $this->resource = $dest;

        return $this;
    }

    /** * Flips an image along it's vertical or horizontal axis. * * @return $this */