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Re: Changing values of one image from ENVI [message #62241 is a reply to message #62222]

Fri, 29 August 2008 17:15

Jonathan Greenberg
Messages: 91
Registered: November 2002

Member

Txomin:

I need to write a thread at some point extolling how much I hate
"ENVI_GET_DATA" -- its one of the most useless commands in the ENVI
language. I am a HUGE fan of ENVI_GET_SLICE and, if you want to get
more complicated, use the built-in envi tiling routines (which are
really just envi_get_slice x a number of lines dependent on memory).
The idea is, you read one line at a time, process it, write the output
one line at a time... No memory issues, fast read/write, all good.

--j

On Aug 29, 8:20 am, txominher...@gmail.com wrote:
> Hello,
> I would like to change some pixel values of one image loaded with
> ENVI_OPEN_FILE, but I cannot load the entire image in memory (this is
> a very big image).
> What I do is to access and process some specific regions of the image
> using ENVI_GET_DATA, by defining subsets in DIMS.
> I really wonder if there is any keyword in the procedure
> ENVI_WRITE_ENVI_FILE, or other procedure (something inverse to
> ENVI_GET_DATA) to perform this, because the only choice that I know is
> to load the whole image in memory in IDL and write it again.
>
> Thanks
>
> Txomin

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[Message index]

		Re: Changing values of one image from ENVI By: jeffnettles4870 on Sat, 30 August 2008 16:17
		Re: Changing values of one image from ENVI By: Jonathan Greenberg on Fri, 29 August 2008 17:15
		Re: Changing values of one image from ENVI By: devin.white on Sun, 31 August 2008 08:30

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