Re: [help-GIFT] 'Re: Ups.

[David Squire]

address@hidden wrote:
> the only reason i went with netPBM was one of my initial goals was to run 
> against a whole one of my images, in native resolution. i've read that PPM 
> has changed formats, and it looked to me like the PPM code in GIFT wouldnt
> handle any images greater than 256x256.
>
>   

GIFT rescales all images to 256x256 before feature extraction. This is 
essential for the way "block features" are extracted and indexed in the 
GIFT. If you have removed this rescaling, then you will have broken the 
feature extraction, since feature IDs depend on block positions, that 
rely on a fixed input image size.

I am not arguing that this is a particularly sensible thing to do, but 
that is the way the GIFT works at present.

The PPM code with the GIFT happily handles images of any size - I have 
used that PPM library in several other applications. It is the GIFT 
feature extraction that *requires* the rescaling to 256x256.

Regards,

David