Topics Topics Edit Profile Profile Help/Instructions Help Member List Member List  
Search Last 1|3|7 Days Search Search Tree View Tree View  

RGB

:: EPE Chat Zone ≠:: ≠Radio Bygones Message Board :: » EPE Forum Archives 2005-2006 » Archive through 02 October, 2005 » RGB « Previous Next »

  Thread Last Poster Posts Pages Last Post
  ClosedClosed: New threads not accepted on this page        

Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

Paul_goodson
Frequent Contributor
Username: Paul_goodson

Post Number: 89
Registered: 05-2005


Rating: N/A
Votes: 0 (Vote!)

Posted on Sunday, 25 September, 2005 - 09:55 am:   Edit Post Delete Post Print Post

I have made a very simple program with a helping hand from John Becker (thanks again) so that I can manually enter a separate file number for red, green & blue in the ASM and make a note of the colour. Of the RGB chip

This was part of my goal so I could pre select, any set colour for the RGB

But trying to make a database has proven a little bit tricky.
Obviously the different combinations of any 3 files of 255 would be too many too start with. (16 million +?)

So I decided to use big jumps of 50 to get started

But in doing so I found that some big changers in say blue does not make much change to the RGB until it gets to a very small number say a file value of 50 downwards.
I.e. not linear.

I have also found that increase in the same number in each file, seems to act as a brightness control?

I would like to see the colour not just change as a rainbow, but change say from a type of light yellow through one colour shade of the rainbow /visible light spectrum, then back again, increasing each time in colour /shade.
Rather than change through all the yellow / shades and on to the next colour /shade in turn.
Hope this make sense

I donít really now where I am going with this, but a small RGB display board would make a nice project?

I wonder if anyone has tried this sort of think before, and maybe shine a little more LIGHT on the subject. (Red green or blue will do )
Meanwhile I will plod along

Thanks Paul
Top of pagePrevious messageNext messageBottom of page Link to this message

Microguy
Frequent Contributor
Username: Microguy

Post Number: 103
Registered: 09-2005

Rating: N/A
Votes: 0 (Vote!)

Posted on Monday, 26 September, 2005 - 02:49 am:   Edit Post Delete Post Print Post

Ya got me lost....

One thing you may want to investigate, is how the human eye responds to color.

I think you're on the right track about it not being linear.

The trick is change. The human eye is a truly wonderful thing. It's weird how it discerns stuff though.

It has very high color resolution, but it can't seem to detect change very well

And as far as I know, the color screens of today's computers are better at displaying color than the eye can see. (I think, I'm not sure, it's been a while since I played with anything like that)

I think that was the case, for color anyway. Seems to me that it could see smaller pixels, but not smaller color changes.

I don't know what you're trying to display or even doing, but you may try experimenting a little.

Display some stuff and see what your eye can differentiate, and then get some other people in there. Wife, kids, test them and see what they can tell.
Top of pagePrevious messageNext messageBottom of page Link to this message

Underlord
Just joined
Username: Underlord

Post Number: 4
Registered: 09-2005

Rating: N/A
Votes: 0 (Vote!)

Posted on Tuesday, 27 September, 2005 - 12:52 am:   Edit Post Delete Post Print Post

You're dead right about the human eye being a weird thing.
This site has some nice demonstrations of how tricky it can be!
http://www.echalk.co.uk/amusements/OpticalIllusions/colourPerception/colourPerce ption.html
Top of pagePrevious messageNext messageBottom of page Link to this message

Underlord
Just joined
Username: Underlord

Post Number: 5
Registered: 09-2005

Rating: N/A
Votes: 0 (Vote!)

Posted on Tuesday, 27 September, 2005 - 01:00 am:   Edit Post Delete Post Print Post

Actually, this is a better entry point for more illusions -
http://www.echalk.co.uk/showproducts.asp?ct02_id=6&level=2&catname=amusements%20>%20optical%20illusions
(You might have to copy the whole line, looks like this web-page stops the link at the '>' character)
Top of pagePrevious messageNext messageBottom of page Link to this message

Microguy
Frequent Contributor
Username: Microguy

Post Number: 113
Registered: 09-2005

Rating: N/A
Votes: 0 (Vote!)

Posted on Tuesday, 27 September, 2005 - 01:11 am:   Edit Post Delete Post Print Post

well, to be honest, part of that is our weird brains!
Top of pagePrevious messageNext messageBottom of page Link to this message

Underlord
Member
Username: Underlord

Post Number: 6
Registered: 09-2005

Rating: N/A
Votes: 0 (Vote!)

Posted on Tuesday, 27 September, 2005 - 01:23 am:   Edit Post Delete Post Print Post

Partly maybe, but drawing the line between eye and brain is difficult since the layers of neurons behind the rods and cones in the retina do pre-processing for brightness dynamic range, edge detection, and other stuff.
Probably because the optic nerve to the brain would otherwise have to be so thick to handle the data bandwidth that our eyes wouldn't be able to move, like Owls' etes.
They've even found built in shape recognition for hands etc' in monkeys retinas!
Top of pagePrevious messageNext messageBottom of page Link to this message

Paul_goodson
Frequent Contributor
Username: Paul_goodson

Post Number: 91
Registered: 05-2005


Rating: N/A
Votes: 0 (Vote!)

Posted on Tuesday, 27 September, 2005 - 07:01 pm:   Edit Post Delete Post Print Post

Thank u all

I am aware of what you are all saying
But all the codes I am using in my project are producing colour/shades except say red 0 green 0 blue 0
But we could call this black.
Any other code gives me a colour in the visible light spectrum that all my family /friends can see, maybe we donít all see light the same, but we donít make different TV or monitor for individual people
Repeating a set code gives the same colour (no matter how we see it)
I was hoping that someone would be able to give some help on the file values to colour
Obviously this sort of thing is done on computers for setting colour, say in ms word EST.

Thanks again
Paul
Top of pagePrevious messageNext messageBottom of page Link to this message

Microguy
Frequent Contributor
Username: Microguy

Post Number: 117
Registered: 09-2005

Rating: N/A
Votes: 0 (Vote!)

Posted on Tuesday, 27 September, 2005 - 11:18 pm:   Edit Post Delete Post Print Post

Sorry, but I still don't understand what you're looking for.

Values for what? Do you want each set of values to have a name? What "file values"? Any set of colors is a valid set. Pick any number between 1 and 255 for any of the three basic colors, and it's valid.

What are you "doing" with these colors? The end result is....... what? What are you looking for? You're generating the colors, isn't that enough?

Any good paint program will let you adjust the colors like you're doing. So I don't see the end result other than maybe you're doing in BASIC or some other program.

Maybe you should look into "Pantone". That pretty well gives each color set something like a name, it's a standard.
Top of pagePrevious messageNext messageBottom of page Link to this message

Microguy
Frequent Contributor
Username: Microguy

Post Number: 118
Registered: 09-2005

Rating: N/A
Votes: 0 (Vote!)

Posted on Tuesday, 27 September, 2005 - 11:32 pm:   Edit Post Delete Post Print Post

Maybe a "database" is the wrong way to go. You need a "command line" so you can type in R123G235B15 and that would give you the RGB nunmbers you're looking for?

As far as a RGB "Board".... I don't know what I would do it. Drink beer and just sit there and look at it?

To me, it sounds like you're just expiermenting with colors. Good luck, have fun and enjoy your self, that's how people learn things.

But I honestly don't know what to say because I don't know what it is you're trying to accomplish.

Maybe you just want loops to generate colors on your color board?? Start with R, increase R by one each loop, and leave the rest alone.

Then increase G by one, then loop through all R1 through 255 again, increase G by one again etc...

Then when G hit's 255, increase B by one and start the whole sequence over again.

A nested, three level loop.

In BACIC it would look something like

for R,G,B = 1 to 255
OUTPUT COLOR (turn on your three LED's or what ever)
R = R+1 Increase R 0-255,
Loop R Loop 255 times
G = G+1 Increase G 0-255
Loop G Loop 255 times
B=B+1 Increase B 0-255
Loop B Loop 255 more times.....
END LOOP (after 16581375 loops)

Maybe that's what you're looking for??
Wish I could help.
Top of pagePrevious messageNext messageBottom of page Link to this message

Paul_goodson
Frequent Contributor
Username: Paul_goodson

Post Number: 92
Registered: 05-2005


Rating: N/A
Votes: 0 (Vote!)

Posted on Wednesday, 28 September, 2005 - 07:04 pm:   Edit Post Delete Post Print Post

Thanks
Top of pagePrevious messageNext messageBottom of page Link to this message

Microguy
Frequent Contributor
Username: Microguy

Post Number: 130
Registered: 09-2005

Rating: N/A
Votes: 0 (Vote!)

Posted on Wednesday, 28 September, 2005 - 07:54 pm:   Edit Post Delete Post Print Post

I really sorry Paul, I wish I could be more help.
Top of pagePrevious messageNext messageBottom of page Link to this message

Underlord
Member
Username: Underlord

Post Number: 9
Registered: 09-2005

Rating: N/A
Votes: 0 (Vote!)

Posted on Wednesday, 28 September, 2005 - 09:00 pm:   Edit Post Delete Post Print Post

On further reflection:-
It sounds like you want to wander round the colour ranges then return to the original colour and then change the hue.
In fact that is part of the name of the colour model I think you need, HSV is Hue, Saturation, Value.
The RGB colour model is good for many things, but it isn't always the best choice.
Lots of info' on converting between colour models by googling:-
http://www.google.com/search?num=100&hl=en&lr=&newwindow=1&safe=off&c2coff=1&q=R GB+HSV+conversion
Also, if you need names for RGB colours, look here for a starter:-
http://www.htmlhelp.com/cgi-bin/color.cgi?rgb=808080

Cheers.
Top of pagePrevious messageNext messageBottom of page Link to this message

Terrym
Regular Contributor
Username: Terrym

Post Number: 46
Registered: 05-2005

Rating: N/A
Votes: 0 (Vote!)

Posted on Thursday, 29 September, 2005 - 06:48 am:   Edit Post Delete Post Print Post

Paul, check this out:- http://www.edn.com/article/CA484496.html?spacedesc=DesignIdeas&taxid=10597

It is a article that uses an RGB LED to display various colours depending on a 0-5v input. Uses a PIC.
TM

Administration Administration Log Out Log Out   Previous Page Previous Page Next Page Next Page