[edit] Last updated: Fri, 17 May 2013

Imagick::setImageCompressionQuality

(No hay información de versión disponible, podría estar únicamente en SVN)

Imagick::setImageCompressionQuality — Establece la calidad de compresión de una imagen

Descripción

bool Imagick::setImageCompressionQuality ( int $quality )

Establece la calidad de compresión de una imagen.

Parámetros

quality: La calidad de compresión de la imagen como un integer

Valores devueltos

Devuelve TRUE en caso de éxito.

Errores/Excepciones

Lanza ImagickException en caso de error.

Imagick::setImageDelay

Imagick::setImageCompression

[edit] Last updated: Fri, 17 May 2013

add a note User Contributed Notes Imagick::setImageCompressionQuality - [3 notes]

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dylan dot arnold at gmail dot com ¶

8 months ago


I had strange results when trying to get good png compression.



I used Imagick::COMPRESSION_ZIP



Here are a few file sizes for a few compression levels.



0: 236,100

1: 274,035

9: 258,379

50: 241,282

100: 240,156



Note the best result at 0. Also I got thrown off for a long time trying to get similar results to gimp. Make sure your image depth is set to 8, it appears to be 16 bits per channel, at least for me.



You can check with identify -verbose filename.png



You can also strip a bit more file size with $image->stripImage();

down

Anonymous ¶

10 months ago


The default value fot the JPEG compression quality appears to be 86.

down

snipes2083 [at] yahoo com ¶

3 years ago


This example shows how to set the compression type, set the compression quality, create a thumbnail and remove unnecessary data in order to reduce file size.





This will use the following functions in reference:


Imagick::setImageCompression


Imagick::setImageCompressionQuality


Imagick::stripImage


Imagick::thumbnailImage


Imagick::writeImage





<?php


    $image = 'image.jpg';


    $directory = '/path/to/image';


    $image_location = $directory . "/" . $image;


    $thumb_destination = $directory . "/t" . $image;


    $compression_type = Imagick::COMPRESSION_JPEG;


   


    $im = new Imagick($image_location);


    $thumbnail = $im->clone;





    $thumbnail->setImageCompression($compression_type);


    $thumbnail->setImageCompressionQuality(40);


    $thumbnail->stripImage();


    $thumbnail->thumbnailImage(100,null);


    $thumbnail->writeImage($thumb_destination);


?>





Now, obviously you don't have to do so much with the variables and the file location.  I only used so many to demonstrate where the images are coming from and where they are going.





NOTE:  The $thumbnail->thumbnailImage(100,null); keeps the aspect ration by setting the second parameter to null.  Read about this at Imagick::thumbnailImage





There is another way to create thumbnails that works quite well if you want to crop the image rather than using the entire image.  Check out Imagick::cropThumbnailImage

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