RLE compression and US RGB images

[leonardorame]

I'm testing the new RLE decompressor and found RGB US images aren't displayed correctly. Please take a look at the following image. The upper image is what I get when I display an uncompressed image, the bottom one is what I get on RLE compressed.

[chafey]

Can you provide a test image by any chance?

On Mon, Aug 10, 2015 at 10:52 AM, Leonardo M. Ramé <notifications@github.com

wrote:

I'm testing the new RLE decompressor and found RGB US images aren't
displayed correctly. Please take a look at the following image. The upper
image is what I get when I display an uncompressed image, the bottom one is
what I get on RLE compressed.

[image: rle]
https://cloud.githubusercontent.com/assets/1405017/9175885/534af4de-3f5e-11e5-8611-f54a13fb264d.png

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#15.

[leonardorame]

Chris, I've sent a .rar containing both the uncompressed and rle version of the same image to your email. I cannot share the samples here because the images aren't anonymized.

[chafey]

Hi Leonardo,

The RLE image is displayed in cornerstone the same way as it does in
Osirix. Have you verified that your RLE encoded image actually displays as
you expected?

Chris

On Mon, Aug 10, 2015 at 12:11 PM, Leonardo M. Ramé <notifications@github.com

wrote:

Chris, I've sent a .rar containing both the uncompressed and rle version
of the same image to your email. I cannot share the samples here because
the images aren't anonymized.

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#15 (comment)
.

[leonardorame]

How do you see it, it must be only one image, not a grid of 3 by 3. I opened it in Weasis and both looks as the top image in my example.

BTW, I'm using:

cornerstone v0.8.1
dicomParser v1.1.4
cornerstoneWADOImageLoader v0.6.0
cornerstoneTools v0.6.2

[leonardorame]

Chris, I've sent to your gmail account the WADO URL I use for this image. Please try to open in Cornerstone.

[leonardorame]

BTW, you can put that URL in http://rawgit.com/chafey/cornerstoneWADOImageLoader/master/examples/index.html and see how it looks.

[chafey]

When I open the RLE image in Osirix, it displays 3x3 images just like it does in cornerstone. Since cornerstone and Osirix display it the same, we should do more testing to make sure that the image is in fact correct. Can you please double check weasis to make sure its not loading the non RLE version and also find another viewer to validate the RLE version against?

[leonardorame]

I also opened it using RadiAnt and looks exactly as in Weasis, it might be that Osirix is not displaying it correctly. The conversion to RLE is done using DCMTK's dcmcrle command.

To download both versions you can change the last part of the URL I sent to you, from contentType=dicom/rle to contentType=dicom/explicit

[leonardorame]

I've sent the test RLE image to a Fuji Synapse PACS and it looks the same as RadiAnt and Weasis.

[chafey]

OK did some research into this and see that foDicom's RLE decoder has a bit more logic in it than ours related to number of segments:

https://github.com/fo-dicom/fo-dicom/blob/development/DICOM%20%5BNative%5D/Dicom.Imaging.Codec.Rle.cpp

Your image has 3 segments in it so that may be the issue. I actually didn't write the RLE code - it was contributed, so this is all new to me. I'll put it on my list to dig into but if someone else has the time I would take a PR! (doesn't look too bad...)

[chafey]

Just checked in a fix for this, can you verify? 0.6.2

[leonardorame]

Confirmed, it's working perfectly right now.