如何使用 dcmtk 从现有的 opencv Mat 图像创建 DICOM 文件？

Question

I am new to DICOM and dcmtk.

I use dcmtk to read a DICOM image and convert it to a opencv Mat. Then do some processing by opencv. Now I want to save the processed image back to DICOM image. But I don't know how to create a DICOM file from a opencv Mat (I only need the pixel data).

I just change the pixel values to do some denoising. Bit depth, resolution and other information stay the same.

I am using simple X-Ray images of SMT or other objects in DICOM format.

Could anyone tell me how to do it with opencv, c++ and dcmtk.

My goal is to Generate a image(DICOM file) with the same pixel data as existing Mat in the specified directory. If possible, please show me some code.

Answer 1

DICOM has the concept of IODs (Information Object Definitions) which is a bit hard to grasp for beginners. With your comments that everything about the pixel format remains constant, and you are just improving the image quality, I would propose that you copy the original image and save a modified version of it back (to a different filename) rather than creating a new image from scratch.

To conform to DICOM, you will have to change a few more attributes in the modified copy of your original image:

• Create a new SOP Instance UID using DcmGenerateUniqueIdentifier
• Set the image type (0008,0008) DERIVED\SECONDARY
• Change all timestamps in the image that refer to the creation of the image (eg Content Date (0008,0023) and Content Time (0008,0033)

Ideally, you would also:

• add a Derivation Description (0008,2111)
• Reference the source image in the Referenced Image Sequence (0008,1140) to tell which original acquisition data was the basis for your derived image
• Assign a new Series Instance UID (0020,000E), Series Number (0020,0011) and SeriesDescription (0008,103E) -> This makes sure that the improved images will appear in a separate "folder"

Sorry for being too lazy to write the code for you. But in the sources of the Dcmtk samples you will find a plethora of references that show how to do these modifications.