From: Markus Schirp <mbj@...>
Date: 2010-03-29T02:56:18+09:00
Subject: Re: divide BMP to YUV channels

Hello,

I dont think the ruby-ml, or the ruby-forums, are an exersise solving
machine... 

But i can give you the following overall picture of your programm
(more pseudocode than ruby)

==== BEGIN

image = open_source_image

y_image = open_new_image
u_image = open_new_image
v_image = open_new_image

for pixel_in_image in image do
  y,u,v = calculate_yuv_for_pixel(pixel)
  write_to_image(y_image,y)
  write_to_image(u_image,u)
  write_to_image(v_image,v)
end

==== END

greetings,

Markus

On Mon, Mar 29, 2010 at 01:02:25AM +0900, Pearce Pearce wrote:
> Hey guys!
> I have an univercity exersise:
> I'm trying to get YUV channels from BMP picture, and output it like 3
> grey images.
> I know the proportion:
> RGB to YUV
> Y  = (0.257 * R) + (0.504 * G) + (0.098 * B) + 16
> V =  (0.439 * R) - (0.368 * G) - (0.071 * B) + 128
> U = -(0.148 * R) - (0.291 * G) + (0.439 * B) + 128
> 
> But don't know how to get it works with Ruby.
> 
> Thanks in advance!
> -- 
> Posted via http://www.ruby-forum.com/.