Image system for retaining contrast when merging image data

• US 20080273784A1
• Filed: 05/01/2008
• Published: 11/06/2008
• Est. Priority Date: 05/04/2007
• Status: Active Grant

• Current Assignee: Siemens Healthcare GMBH (Siemens AG)
• Original Assignee: Siemens AG
• Inventors: Pfister, Marcus
• Granted Patent: US 8,200,040 B2
• Time in Patent Office: Days
• US Class Current: 382/131
• CPC Class Codes: G06T 15/503 Blending, e.g. for anti-aliasing
• CPC Class Codes: G06T 2207/10072 Tomographic images
• CPC Class Codes: G06T 2207/10121 Fluoroscopy
• CPC Class Codes: G06T 2207/20221 Image fusion; Image merging
• CPC Class Codes: G06T 2207/30021 Catheter; Guide wire
• CPC Class Codes: G06T 2207/30101 Blood vessel; Artery; Vein; Vascular
• CPC Class Codes: G06T 5/009 Global, i.e. based on properties of the image as a whole applied in cameras using an electronic image sensor H04N23/80, H04N23/70
• CPC Class Codes: G06T 5/50 using two or more images, e.g. averaging or subtraction
• CPC Class Codes: G06T 5/92 based on global image properties
• CPC Class Codes: G06T 7/194 involving foreground-background segmentation
• CPC Class Codes: G16H 30/20 for handling medical images, e.g. DICOM, HL7 or PACS

Abstract

The invention relates to a method for the joint of registering, archiving, contrast-retaining merging, and visualizing of 2D x-ray images and reconstructed 2D projections or 3D views of generated image data in minimally invasive medical interventions or operations performed under x-ray control on internal organs, areas of tissue, lesions, or pathological structures in a patient'"'"'s body. A first image and the image data of a second image being mixed over the first image are mutually linked, co-registered, and merged using an alpha-channel-based mixing technique, whereby the color values or gray-scale values of the individual pixels of the first image are prior to being mixed-over with the segmented foreground of the second image brightened through the application of a color-value or gray-scale-value for compensating or lessening the reduction in contrast that occurs during mix-over in the first image before being displayed graphically on a monitor terminal.

Claims

1-23. -23. (canceled)

24. A method for retaining a contrast when merging image data of at least two images of a patient, comprising:

mixing image data of a second image of the patient over with image data of a first image of the patient using an alpha-channel-based mixing technique;

determining a compensating pixel value term for compensating a reduction of the contrast occurring during the mix-over; and

brightening pixel values of the first image prior to being mixed-over with a foreground region of the second image by applying the compensating pixel value term for retaining the contrast.

25. The method as claimed in claim 24, wherein the image data of the first image is mutually linked, co-registered, and merged with the image data of the second image.

26. The method as claimed in claim 24, wherein the image data of the first image and the second image is stored mergedly or separately.

27. The method as claimed in claim 24, wherein the image data of the first image and the second image is graphically displayed.

28. The method as claimed in claim 24, wherein color values or gray scale values of the pixels of the first image are brightened prior to being mixed-over.

29. The method as claimed in claim 24, wherein a coordinate transformation is performed so that an identical image object requiring to be overlaid in the first and the second image is overlaid exactly congruently.

30. The method as claimed in claim 24, wherein an image object in the foreground region of the second image is segmented from an object background of the second image and color values or gray-scale values of the object background are subtracted from color values or gray-scale values of the second image.

31. The method as claimed in claim 24, wherein the compensating pixel value term is an image operator serving.

32. The method as claimed in claim 24, wherein the compensating pixel value term is an additive pixel value offset dependent on a blending factor of the alpha-channel-based mixing technique.

33. The method as claimed in claim 32, wherein the additive pixel value offset is a location-independent and constant offset.

34. The method as claimed in claim 32, wherein the pixel values in the foreground region of the second image entered multiplicatively into the pixel value offset.

35. The method as claimed in claim 24, wherein the compensating pixel value term is a multiplicative pixel value factor dependent on a blending factor of the alpha-channel-based mixing technique.

36. The method as claimed in claim 35, wherein the pixel values in the foreground region of the second image are entered multiplicatively into the pixel value factor in a standardized form.

37. The method as claimed in claim 24, wherein the first image is a two-dimensional x-ray recording of the patient and the second image is a reconstructed 2D or 3D projection of the first image.

38. An image system for retaining a contrast when merging image data of at least two images of a patient, comprising:

an image processing unit that;

mixes image data of a second image of the patient over with image data of a first image of the patient using an alpha-channel-based mixing technique,

determines a compensating pixel value term for compensating a reduction of the contrast occurring during the mix-over, and

brightens pixel values of the first image prior to being mixed-over with a foreground region of the second image by applying the compensating pixel value term for retaining the contrast.

39. The image system as claimed in claim 38, wherein the image processing unit mutually links, co-registers, and merges the image data of the first image with the image data of the second image.

40. The image system as claimed in claim 38, wherein the image data of the first image and the second image is stored mergedly or separately.

41. The image system as claimed in claim 38, wherein the image data of the first image and the second image is graphically displayed.

42. The image system as claimed in claim 38, wherein color values or gray scale values of the pixels of the first image are brightened prior to being mixed-over.

43. A computer software program product executed in a computer for retaining a contrast when merging image data of at least two images of a patient, comprising:

a computer sub program that;

mixes image data of a second image of the patient over with image data of a first image of the patient using an alpha-channel-based mixing technique,

determines a compensating pixel value term for compensating a reduction of the contrast occurring during the mix-over, and

brightens pixel values of the first image prior to being mixed-over with a foreground region of the second image by applying the compensating pixel value term for retaining the contrast.