[TYPO3-dev] resize images : gd and freetype

[Jigal van Hemert]

Hi,

On 19-5-2011 10:45, Ismaël Bidau wrote:
> I'm just asking why TYPO3 needs freetype just for scaling image (Install
> toll > Image Processing > Gd library fonction has "Fatal error Call to
> undefined function ImageTTFBBox()").

This part of the Install Tool tests not only pure GD library functions, 
but also rendering of text. Even if IM/GM is present the Freetype 
routines are used to render text in images.

In PHP you need GD library to render text with Freetype. That is 
probably the reason why the text rendering tests are listed on the Gd 
library function page in the Install Tool.

> And perhaps having GD2 per default to resize images is a good idea.
> Nearly everybody want to resize images and it could simplified the
> system requirements.
> http://forge.typo3.org/issues/20107

Using GD library for resizing has one huge limitation and that is that 
it cannot be used for really big images. The entire image is loaded into 
memory as a 32-bit bitmap. For images produced by modern cameras in an 
already memory hunger application such a TYPO3 that could easily result 
in out-of-memory errors. (Another limitation is the file types supported 
by GD)

On the positive side: I am currently writing a new graphics library for 
TYPO3 v4. It will use handlers to perform the necessary operations. I 
will try to add handlers using GD library, ImageMagick 6, GraphicsMagick 
and possibly Imagick and Gmagick (the PHP libraries for IM/GM which do 
no require the use of exec() functions).
The GD handler needs to use some checks for available memory to safely 
create thumbnails.

I will do my best to have this included in TYPO3 4.6.

-- 
Kind regards / met vriendelijke groet,

Jigal van Hemert.