comp.lang.idl-pvwave archive: archive » Re: IDL 8 image function

Home » Public Forums » archive » Re: IDL 8 image function

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

Re: IDL 8 image function [message #74776 is a reply to message #74775]

Wed, 02 February 2011 08:11

sh
Messages: 26
Registered: April 2010

Junior Member

On Feb 2, 4:51 pm, Paulo Penteado <pp.pente...@gmail.com> wrote:
> On Feb 2, 1:30 pm, sh <sebastian.h...@gmail.com> wrote:
>
>
>
>> On Feb 2, 2:31 pm, sh <sebastian.h...@gmail.com> wrote:
>
>>> On Feb 2, 12:44 pm, sh <sebastian.h...@gmail.com> wrote:
>
>>>> On Feb 2, 11:44 am, David Forcadell <david...@gmail.com> wrote:
>
>>>> > On Feb 2, 11:02 am, sh <sebastian.h...@gmail.com> wrote:
>
>>>> > > Hi,
>
>>>> > > Is there any option/keyword to turn of the scaling between 0-255? I
>>>> > > have already scaled by values e.g. between 0 and 100 because I only
>>>> > > want to use this colors in the colortable, and not all of them!
>>>> > > Thanks!
>
>>>> > > Sebastian
>
>>>> > I am not sure that i understand you question, but perhaps you want
>>>> > this :
>
>>>> > result=BYTSCL( MAT_IN , TOP=100)
>
>>>> Yes I do it exactly like this, but image() rescales it again between 0
>>>> and 255. How to turn this off?
>
>>> Another question, is there any possiblity to set a background value
>>> like NaN in iimage?
>
>>> All NaN values are transformed to 0 after bytscl?
>
>> Ok I think I found the problem. Within idlitvisimage__define.pro in
>> line 1801 there is the bytscl, without the possibility to turn it off.
>
>> Would be nice to specify the top and bottom or even turn it off if the
>> data is already scaled.
>
>> Then the next think is the colorbar which didn't match when I update
>> line 1801 with top and bottom.
>
> If I understand this right, you can to map your data into RGB, and
> give image() a 3 channel image, which it will display as it is. If you
> do that, you can also make it a 4 channel image, with the alpha
> (transparency) channel determined by the presence of NaNs, to make
> NaNs transparent.

I already tried an RGB image. Indeed it works for the image but since
I would like to use the first color as a background value the colorbar
has it included!

Maybe it will work with RGBA, I'll try that.

Thanks David, but yours is direct graphics and I would like to play
around with the new graphics instead using your graphics as usual ;)

Report message to a moderator

[Message index]

		Re: IDL 8 image function By: penteado on Wed, 02 February 2011 11:20
		Re: IDL 8 image function By: sh on Wed, 02 February 2011 09:35
		Re: IDL 8 image function By: David Fanning on Wed, 02 February 2011 09:00
		Re: IDL 8 image function By: sh on Wed, 02 February 2011 08:51
		Re: IDL 8 image function By: Paul Van Delst[1] on Wed, 02 February 2011 08:35
		Re: IDL 8 image function By: David Fanning on Wed, 02 February 2011 08:21
		Re: IDL 8 image function By: sh on Wed, 02 February 2011 08:11
		Re: IDL 8 image function By: penteado on Wed, 02 February 2011 07:51
		Re: IDL 8 image function By: David Fanning on Wed, 02 February 2011 07:43
		Re: IDL 8 image function By: sh on Wed, 02 February 2011 07:30
		Re: IDL 8 image function By: sh on Wed, 02 February 2011 05:31
		Re: IDL 8 image function By: sh on Wed, 02 February 2011 03:44
		Re: IDL 8 image function By: David Forcadell on Wed, 02 February 2011 02:44
		Re: IDL 8 image function By: sh on Thu, 03 February 2011 00:28
		Re: IDL 8 image function By: sh on Thu, 03 February 2011 00:28
		Re: IDL 8 image function By: sh on Thu, 03 February 2011 00:28

Previous Topic:	Lists in strsplit
Next Topic:	Error Bar Thoughts

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Wed Oct 08 19:23:34 PDT 2025

Total time taken to generate the page: 0.00432 seconds