How to generate on the fly images with image_lib?

How to generate on the fly images with image_lib? - Printable Version

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How to generate on the fly images with image_lib? - El Forum - 12-12-2009

[eluser]Sinclair[/eluser]
Hi,

I have been testing image_lib, but I can't generate on the fly images with them.

There are some examples on how to generate on the fly images with image_lib?

Best Regards.

How to generate on the fly images with image_lib? - El Forum - 12-12-2009

[eluser]JoostV[/eluser]
Create a controller that outputs the image, image_lib setting 'dynamic_output' set to true, see http://ellislab.com/codeigniter/user-guide/libraries/image_lib.html.
Set this controller as your source.

Code:
// Assuming your controller name is 'image', method 'generate'

<img src="/image/generate/some_image" alt="foo" />

NB Creating images on-the-fly puts a massive strain on your server.

How to generate on the fly images with image_lib? - El Forum - 12-12-2009

[eluser]bretticus[/eluser]
Another tip. You can easily use routes in CI to fake an image path like so (config/routes.php)

Code:
$route['d_images/some_image.jpg'] = "image/generate/some_image";

Now your image src path can look normal.

Code:
<img src="/d_images/some_image.jpg" alt="foo" />

Of course your generate method needs to dynamically produce the image. Here's a small snippet to demonstrate:

Code:
function generate()

{

    //try to force no caching of the image

    header("Expires: Mon, 26 Jul 1997 05:00:00 GMT"); // Date in the past

    header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT"); // always modified

    header("Cache-Control: no-store, no-cache, must-revalidate"); // HTTP/1.1

    header("Cache-Control: post-check=0, pre-check=0", false);

    header("Pragma: no-cache"); // HTTP/1.0

    // set header to content type for jpeg.

    header("Content-type: image/jpeg");

    //set path to image.

    $imgname = '/path/to/images/background.jpg';

    $font = '/path/to/fonts/arial.ttf';

    $im = @imagecreatefromjpeg($imgname)

        or die("Cannot Initialize new GD image from file: $imgname");        

    $text_color = imagecolorallocate($im, 239, 255, 253);

    imagettftext($im, 16, 0, 100, 100, $text_color, $font, "text to superimpose");

    imagejpeg($im);

    imagedestroy($im);

}

There are many image functions in PHP. See the PHP Manual for details.

How to generate on the fly images with image_lib? - El Forum - 12-12-2009

[eluser]Sinclair[/eluser]
Hi,

First of all, thanks for the replys.

I have found something that works, but I need to resize and watermark on the fly, whitout changing the original image file.

I have to functions that I'am testing:

Code:
function get_photo($folder, $file){

        $path = 'c:/xampp/htdocs/acomp_www/' . $folder . '/' . $file;

        #$path = 'c:/xampp/htdocs/acomp_www/1/2.jpg';

        #$this->load->library('image_lib');                    

           #$this->image_lib->clear();

        $imageinit['image_library']     = 'GD2';

        $imageinit['quality']            = '100%';

        $imageinit['dynamic_output']    = TRUE;

        #$imageinit['create_thumb']    = FALSE;

        $imageinit['source_image']         = $path;

        #$imageinit['maintain_ratio']     = false;

        $imageinit['width']             = '200';

        $imageinit['height']             = '150';

        $imageinit['wm_type'] = 'overlay';

        $imageinit['wm_overlay_path'] = 'c:/xampp/htdocs/acomp_www/1/w.png';

        $imageinit['wm_padding'] = '0';

        $imageinit['wm_hor_alignment'] = 'bottom';

        $imageinit['wm_vrt_alignment'] = 'center';

        $this->image_lib->initialize($imageinit);

        $this->image_lib->watermark();

        #$this->image_lib->clear();

        $this->image_lib->resize();

        if(!$this->image_lib->resize() && !$this->image_lib->watermark()){

        echo $this->image_lib->display_errors();

        } 

    }

This function, Watermarks On The Fly, but not resize.

Code:
function get_photo($folder, $file){

        $path = 'c:/xampp/htdocs/acomp_www/' . $folder . '/' . $file;

        $this->load->library('image_lib');

        $config['thumbnail'] = array('source_image' => $path,

                                     'width' => '200',

                                     'height' => '150',

                                     'dynamic_output' => true);

        $this->image_lib->initialize($config['thumbnail']);

        $this->image_lib->resize();

        $this->image_lib->clear();

        $config['watermark'] = array('wm_type' => 'overlay',

                                     'source_image' => $path,

                                     'wm_overlay_path' => 'c:/xampp/htdocs/acomp_www/1/w.png',

                                     'wm_padding' => '20',

                                     'dynamic_output' => true,

                                     'create_thumb' => 'false',

                                     'wm_hor_alignment' => 'bottom',

                                     'wm_vrt_alignment' => 'center');

        $this->image_lib->initialize($config['watermark']);

        $this->image_lib->watermark();    

    #    if(!$this->image_lib->resize() && !$this->image_lib->watermark()){

        #echo $this->image_lib->display_errors();

        #}

    }

This function resize and watermarks, but when watermarking, change the image, add the watermark to the image withthe original image size.

My question. How can I get real Resize and Watermarking On The Fly without changing the original image files? Can you give me some clues?

Best Regards,