comp.lang.idl-pvwave archive: archive » Re: Conversion floating point to byte or integer

Home » Public Forums » archive » Re: Conversion floating point to byte or integer

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

Re: Conversion floating point to byte or integer [message #56292]

Thu, 11 October 2007 18:44

beardown911
Messages: 21
Registered: March 2007

Junior Member

On Oct 11, 4:04 pm, "M. Katz" <MKatz...@yahoo.com> wrote:
> You have to guard against byte values going below zero.
> Here is what I would recommend.
> 1) Immediately convert the raw data into float, before any processing.
> 2) Subtract the background array but "crop" any negative values at
> zero.
> image1 = (raw_data - background ) > 0.
> 3) Then apply your calibration
> image2 = image1 * calibration
> If instead you have to divide by the calibration array, watch out
> for zeros.
> image2 = image1 / (calibration > 1.) might be a format you should
> consider.
> (The 1. here is just an example. It depends on your actual data.)
>
> Of course be careful about spikes or zeros in the calibration
> file or background file. Those can cause problems.
>
> MKatz

Thanks a lot.

Kim

Report message to a moderator

[Message index]

		Re: Conversion floating point to byte or integer By: beardown911 on Thu, 11 October 2007 18:44
		Re: Conversion floating point to byte or integer By: M. Katz on Thu, 11 October 2007 14:04
		Re: Conversion floating point to byte or integer By: beardown911 on Thu, 11 October 2007 06:22
		Re: Conversion floating point to byte or integer By: beardown911 on Thu, 11 October 2007 06:20
		Re: Conversion floating point to byte or integer By: Maarten[1] on Thu, 11 October 2007 01:05
		Re: Conversion floating point to byte or integer By: Jean H. on Wed, 10 October 2007 23:08
		Re: Conversion floating point to byte or integer By: beardown911 on Wed, 10 October 2007 21:20
		Re: Conversion floating point to byte or integer By: Jean H. on Wed, 10 October 2007 16:44

Previous Topic:	Re: Minor IDL code changes cause large slowdowns elsewhere in code
Next Topic:	Re: Problem while deleting shape file

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Fri Nov 28 09:50:33 PST 2025

Total time taken to generate the page: 0.00794 seconds