Retrieving channel's base value type

[Hugo]

Hi,

In order to build an histogram from an image view, I need to retrieve channels' base value type. Unfortunately it does not work for channels that use scoped_channel_value as value_type.

For the moment, I have added : typedef BaseChannelValue base_type; in scoped_channel_value's declaration. Yet, it's not a viable solution, especially if other people use my program.

Is there another way to retrieve the BaseChannelValue from a scoped_channel_value ?

Best regards,

Hugo

[Lubomir Bourdev]

Hugo,

You can always do something non-intrusive like your own metafunction:

template <typename Channel>
struct base_channel_value {
    typedef typename channel_traits<Channel>::value_type type;
};

template <typename BaseChannelValue, typename MinVal, typename MaxVal>
struct scoped_channel_value {
    typedef BaseChannelValue type;
};

Lubomir

[Lubomir Bourdev]

Sorry I meant the second one to be specialization:

template <typename BaseChannelValue, typename MinV, typename MaxV>
struct base_channel_value<scoped_channel_value<BaseChannelValue,MinV,MaxV> > {
    typedef BaseChannelValue type;
};