在DICOM中处理无损jpeg图像

Question

I have a DICOM Image which has the image stored as the following JPEG Lossless, Nonhierarchical, First- Order Prediction (Processes 14 [Selection Value 1]): Default Transfer Syntax for Lossless JPEG Image Compression

I can open the original DICOM file in Irfanview, and that works fine, but when I take the Bit stream from the DICOM file and save it as a file, and try to open it in Irfanview, I get an error "Unsupported JPEG process/compression: SOF type 0xc3"

I've checked that the byte stream matches that of the DICOM file, and checked that it starts with, FF D8 FF E0 00 10 4A 46 49 46 which seems to be a standard JPEG header.

There are 4 bytes at the end of the DICOM file beyond what is specified by the length of the tag, are these some sort of DICOM footer?

Any ideas what it would take to get this to open? I've included the JPEG_LS plugin in Irfanview. This is a continuation of Length of PixelStream in EvilDicom library

Answer 1

That data is not JPEG-LS, it is JPEG Lossless (1.2.840.10008.1.2.4.70), a completely unrelated compression format. Very few image readers support that type of JPEG data. I've only known it to be used in the context of DICOM.

I believe also that it may not necessarily be one contiguous block of JPEG data, but rather be broken into segments (encapsulated DICOM) with DICOM tag wrappers.

Perhaps Irfanview knows how to read it when in the context of a DICOM, but fails to read it as normal JPEG data, since it is such a rare JPEG format. Or perhaps the data stream is not contiguous JPEG data, but contains DICOM elements as well.