From: Sylvia on
Thanks Tim

It solved the issue

Sylvia

>Sylvia wrote:
>(top posting fixed)
>>> Sylvia wrote:
>>>> Hi,
>>>>
>>>> I want to use imshow command imshow(I,[low high]) for displaying
>> different
>>>> images. All images have different minimum and maximum intensity
values.
>> I
>>>> want to show all images on the same scale i.e between same range of
>> maximum
>>>> and minimum intensities.
>>>> say image1 has minimum intensity values of 0.5 and maximum 0.2
>>>> image2 has minimum intensity values 0.8 and maximum 0.3.
>>>> I want to display these images in the same range of [-1 1]
>>>>
>>>> The command
>>>> imshow(Image,[-1 1]) wont work
>>>>
>>>> The standard imshow command can do compressing the range of
intensities
>> but
>>>> how to expand the range?
>>>>
>>> Images are generally encoded as sets of non-negative numbers. Are you

>>> sure you don't want to use the range [0, 1]?
> >
> > As those are the images phase, would be best to have range in
>negative and
> > positive but expanding the display range from [0.2 0.5] to [0 1]
>would also
> > give some help.
>
>So first you have the task of converting a non-image to an acceptable
>range for an image: Image = ImagePhase + 1
>
>Then you can show it:
>
>imshow(ImagePhase + 1, [0, 2])
>
>Not, mind you, that I'm sure that the negative argument in imshow was
>your problem in the first place -- that was just an educated guess.
>
>--
>Tim Wescott
>Control system and signal processing consulting
>www.wescottdesign.com
>
From: Sylvia on
Thanks Tim

It solved the issue

Sylvia

>Sylvia wrote:
>(top posting fixed)
>>> Sylvia wrote:
>>>> Hi,
>>>>
>>>> I want to use imshow command imshow(I,[low high]) for displaying
>> different
>>>> images. All images have different minimum and maximum intensity
values.
>> I
>>>> want to show all images on the same scale i.e between same range of
>> maximum
>>>> and minimum intensities.
>>>> say image1 has minimum intensity values of 0.5 and maximum 0.2
>>>> image2 has minimum intensity values 0.8 and maximum 0.3.
>>>> I want to display these images in the same range of [-1 1]
>>>>
>>>> The command
>>>> imshow(Image,[-1 1]) wont work
>>>>
>>>> The standard imshow command can do compressing the range of
intensities
>> but
>>>> how to expand the range?
>>>>
>>> Images are generally encoded as sets of non-negative numbers. Are you

>>> sure you don't want to use the range [0, 1]?
> >
> > As those are the images phase, would be best to have range in
>negative and
> > positive but expanding the display range from [0.2 0.5] to [0 1]
>would also
> > give some help.
>
>So first you have the task of converting a non-image to an acceptable
>range for an image: Image = ImagePhase + 1
>
>Then you can show it:
>
>imshow(ImagePhase + 1, [0, 2])
>
>Not, mind you, that I'm sure that the negative argument in imshow was
>your problem in the first place -- that was just an educated guess.
>
>--
>Tim Wescott
>Control system and signal processing consulting
>www.wescottdesign.com
>