dcm2jpg and wado jpeg problem - white background

[Thiago Henrique Busarello]

When i export the study, some imagens has a white background. In DICOM format, she stay as a normal background (black).

In weasis, imported as a DICOM...

When exported using dcm2jpg tool...

The same happens when call WADO uri for image/jpeg type...

However, in the Weasis JPEG exporter, its works...

DCM4CHEE ARC and TOOLS version 5.17.1

Weasis version 3.5.2

Images https://drive.google.com/file/d/15Q4kU4G-3g2hTycP6-gdPY4phhLJ4J9A/view?usp=sharing

Can someone help me?

[Nicolas Roduit]

The rendering is different in Weasis and dcm4chee. Fill a bug in dcm4che that seems to have a problem with the Monochrome1 type.

[gunterze]

It's caused by the fact, that the decompressed pixel values have values > 1023, which conflicts with

1286: (0028,0101) US #2 [10] BitsStored
1296: (0028,0102) US #2 [9] HighBit

dcm2jpg and wado jpeg apply a bitmask according the value of Bits Stored, which results in the white background. You get the same result with DCMTK's dcmj2pnm.

I am thinking about to implement an auto-correction of the value of Bits Stored on decompression of lossy compressed images.

[gunterze]

According DICOM PS3.5: Valid Values of Pixel Data Related Attributes for JPEG Lossy Transfer Syntaxes using Standard Photometric Interpretations, Bits Stored must be either 8 or 12 - and can't be 10 - for JPEG Extended Transfer Syntax. So I will just set

BitsStored = 12
HighBit = 11

on decompression of JPEG Extended compressed images with BitsStored > 8.