Subject: Re: [boost] [gil] New IO release
From: Christian Henning (chhenning_at_[hidden])
Date: 2010-10-11 11:41:00


Hi Phil,

>
> This sounds great. It's much closer to what I was trying to suggest
> back in March when we last had this discussion.
>
> I've had a quick look at your libjpeg interface. Two features that I
> often use are dct_method=JDCT_IFAST and scaling down 2x or 4x using
> scale_num and scale_denom. It would be interesting to know whether (a)
> your existing code lets me use these via a "native handle", or (b) they
> could be added easily. My preference would still be to have a thinner
> library-wrapping layer, i.e. just a C++ification of the C library
> interface (see e.g. http://chezphil.org/tmp/LibJpeg.hh for an
> incomplete example), underneath the gil interface. But what you're
> proposing sounds much closer to this than Christian's proposal.

Using JDCT_IFAST is possible. Have a look at image_read_settings<
jpeg_tag >. As for the scaling. I believe I have tried that in a
simple test case and didn't get it to work. Do you have some libjpeg
code uses such functionality?

Regards,
Christian