Re: Downscaling algorithms

From: Stefan Seefeld (stefan_at_[hidden])
Date: 2019-05-27 23:21:15

On 2019-05-28 1:05 a.m., Olzhas Zhumabek wrote:
> I implemented the Lanczos algorithm in a very rough form. Here is the link
> to the file: link
> <https://github.com/simmplecoder/gil/blob/lanczos/test/image_processing/lanczos_scaling.cpp>
> .
> It needs a dependency on constants, as 3.14 might be too inaccurate with
> images of much bigger resolution.  Can we bring in boost.constants (not
> sure about exact name)?

In theory, I'm not opposed to the idea. (I believe the right spelling 
would be

|constdoublepi =boost::math::constants::pi<double>();|

But if all we need is the value of pi, I think we can simply clone the 
definition (either from `Boost.Constants`, or by just using the 
pre-defined `M_PI` macro directly.

> I've tried to run it on a vividly colored image, and results are awesome
> for my untrained eye and non-HDR monitor
> (I know, means nothing).
>
> I will start refactoring it into something more readable and versatile.

Cool ! :-)

> P.S. I also noticed that putting some sentences on different lines is
> better to make it easier to quote.

"sentences" referring to inline documentation, or to C++ statements ?

In either case, yay for readability ! :-)

(You know this is spelled out in the coding standard 
(https://github.com/boostorg/gil/blob/develop/CONTRIBUTING.md#guidelines), 
yes ?

Best,

Stefan
-- 
       ...ich hab' noch einen Koffer in Berlin...