Re: [boost] [GIL] kth_channel_view

Subject: Re: [boost] [GIL] kth_channel_view
From: Christian Henning (chhenning_at_[hidden])
Date: 2010-08-03 17:51:53

Hi Fabien, I know it took a while but I've some time to see what's going on.

>
> Another interesting possibility is:
>    typedef kth_channel_view_type< 0, const rgb8_view_t> KthChannelView;
>    typename KthChannelView::type first = KthChannelView::make( const_view(img) );

This doesn't compile on my machine. VC10 is the compiler I'm using.
Stripping the const's helps me:

typedef kth_channel_view_type< 0, rgb8_view_t> KthChannelView;
KthChannelView::type first = KthChannelView::make( view( img ) );

Does it work on your machine?

>
> It can be a good thing to directly use channel type, like this:
>    typedef channel_view_type< red_t, const rgb8_view_t>::type view_t;
>    view_t first = channel_view<red_t>( const_view( img ));

Same here. This works:

typedef channel_view_type< red_t, rgb8_view_t>::type view_t;
view_t first_ = channel_view< red_t >( view( img ));

>
> I have written some code to do that, based on kth_channel_view_type. It's maybe intersting to include in gil.

Thanks! I have added this code to the toolbox extension. See here:

http://code.google.com/p/gil-contributions/source/browse/trunk/gil_2/boost/gil/extension/toolbox/channel_view.hpp

Regards,
Christian