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Re: Unknown data type [message #42115 is a reply to message #42107]

Wed, 29 December 2004 05:43

R.Bauer
Messages: 1424
Registered: November 1998

Senior Member

Julio wrote:

> Hello folks,
>
> I can read byte or integer images using byte or integer arrays, like:
>
> byte_image=bytarr(samples, rows) or
> integer_image=intarr(samples, rows)
>
> In both cases I must know the data type. But, when I don't know the
> data type, how can I do to read the images? Is there some way to
> verify the file format before reading into an array?
>
> Thanks for comments and happy New Yearï¿œ
>
> Julio

This depends on what else you know about the data.
In your case it's only the type case which you want to determine. If you
probably knows how much lines and columns the image should have then it is
easy to calculate from the file size the length of the type you need for
reading the whole file. If you got 4byte as type it could be long or float.
Both will be able to read the whole file. You could first read it by float
and then test if float is necessary. If not read it a second time by long.

cheers
Reimar

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Forschungszentrum Juelich
email: R.Bauer@fz-juelich.de
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[Message index]

		Unknown data type By: julio on Thu, 30 December 2004 05:59
		Re: Unknown data type By: R.Bauer on Wed, 29 December 2004 05:43
		Re: Unknown data type By: David Fanning on Tue, 28 December 2004 20:11
		Re: Unknown data type By: ed on Tue, 28 December 2004 19:29
		Re: Unknown data type By: David Fanning on Mon, 27 December 2004 19:19

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