[ImageJ-devel] Can you compare two images(for example two jpeg images)

[Curtis Rueden]

Hi Shouvanik,

> I want to take two images (possibly jpeg etc.) and compare them to find
> whether they are equal or unequal.

One simple way is to use the Image Calculator plugin of ImageJ (in the
Process menu) to subtract one image from the other. This only works if they
were both produced using the exact same acquisition mechanism and settings.

I also suggest using a lossless file format (i.e., not JPEG) when doing
quantitative analysis. See this page for details:

    http://fiji.sc/IP_Principles

> Does the api (written by you) "ImgLib2" anyway supports this.

You could certainly use ImgLib2 to subtract two images. The base ImgLib2
library supports this via the use of cursors that iterate over your images,
so that you can perform the subtraction and/or comparison pixel-by-pixel.
The ImgLib2 OPS extension supports doing this in a functional way over the
entire image at once.

See the ImgLib2 Examples for an introduction to ImgLib2:

    http://fiji.sc/ImgLib2_Examples

There is not a lot of documentation on ImgLib2 OPS yet but you can read an
overview of sorts at:

    https://groups.google.com/d/msg/fiji-devel/YDqzss-mQjI/mbFiZIeOTPgJ

HTH,
Curtis

P.S. I am not a main author of ImgLib2: that distinction goes to Stephan
Saalfeld, Stephan Priebisch and Tobias Pietzsch. And Barry DeZonia is the
main author of ImgLib2 OPS.


On Tue, Feb 5, 2013 at 12:20 AM, Shouvanik Haldar <
shouvanik.haldar at gmail.com> wrote:

> Hi,
>
> Greetings!
>
> I am trying hard to arrive at a solution. I want to take two images
> (possibly jpeg etc.) and compare them to find whether they are equal or
> unequal.
>
> Does the api (written by you) "ImgLib2" anyway supports this.
>
> Many thanks in advance for your help.
>
> --
> Thanks,
> *Shouvanik*
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://imagej.net/pipermail/imagej-devel/attachments/20130205/7506e632/attachment.html>