[Qt-interest] How can I read a large image fastly?

[Kermit Mei]

Jason H wrote:
> You can;t speed loading, but you can load it into memory then use QPixmap::copy() to access/scale,etc only the visible area.
>
>
> Or are you trying to scale the thing in entirety?
> There are a couple scaling algorithms. Also avoid use of SmoothPixmapTransform,as you'll be doing sub-pixel interpolation.
>   
<snip>

Dear Jason,
   
    Would you like to give me more details about it? I don't know how to 
deal with it as what you told me to.
For example:
1.How to load it in memory first? QPixmap::load() ? This is more slower 
then QImage::load().

2.What "scaling algorithms"  should I use?

Thanks.
B.R
Kermit