[fpc-pascal] FPImage and GetDataLineStart

[Leonardo M. Ramé]

--- On Thu, 4/21/11, Marco van de Voort <marcov at stack.nl> wrote:

> From: Marco van de Voort <marcov at stack.nl>
> Subject: Re: [fpc-pascal] FPImage and GetDataLineStart
> To: "FPC-Pascal users discussions" <fpc-pascal at lists.freepascal.org>
> Date: Thursday, April 21, 2011, 6:41 AM
> In our previous episode, Sven Barth
> said:
> > Am 20.04.2011 22:20, schrieb Leonardo M. Ram?:
> > > Hi, I need to write a function that replaces
> TLazIntfImage by using fpImage, and I can't find an
> alternative to GetDataLineStart. How can I replace it?.
> > 
> > Maybe I get your intention wrong, but TLazIntfImage is
> already using 
> > fpImage and it derives from a TFPCustomImage itself.
> 
> True, but TFPCustomImage is abstact wrt memory layout and
> doens't provide
> row level access, only pixel level access.
> 
> Only TFPMemoryImage adds the memory access, but IIRC only
> 64-bit pixels.
> (16-bit RGBA)
> 
> While these abstractions make it easy to make fp/fcl-image
> somewhat
> complete, they are also very memory hungry and slow.
> 
> IIRC I accelerated loading/saving simple 8-bit BMP images
> 20 to 50 times in
> my work code.
> 

Do you care to share some insights about what you did to accelerate it?

Leonardo M. Ramé
http://leonardorame.blogspot.com