Device for differential image determination
AssigneeU.S. Philips Corporation
InventorLeonardus A. J. Verhoeven
Life of this patent
Estimating the term…
Abstract
Two image processing devices having different time delays are used to generate time difference images having high signal-to-noise ratios. The image processing devices may be real time image processors having only one image memory wherein consecutive images are sequentially fed in digital form to a recursive filter. In such devices the memory is employed in the recursive filter as a "delay element", as a result of which noise integration and differential image determination between consecutive images takes place.
Claims3
A device for processing current image information which has been separated into image elements comprising:
- first video processor means comprising a first memory, multiplying and addition circuits connected at least with the first memory to form recursive filter means which functions to multiply the current image information by a factor .alpha..sub.1, to multiply image information received from an output of the first memory by a factor (1-.alpha..sub.1), with 0.ltoreq..alpha..sub.1,.ltoreq.1, to add the resulting products on an elemental basis and to supply the resulting sum to an input of the first memory;
- second video processor means comprising a second memory, multiplying and addition circuits connected at least with the second memory to form a recursive filter which functions to multiply the current image information by a factor .alpha..sub.2, to multiply image information received from an output of the second memory by a factor (1-.alpha..sub.2), with 0.ltoreq..alpha..sub.2 .ltoreq.1, to add the resulting products on an elemental basis and to supply the resulting sum to an input of the second memory;
- subtraction means connected to outputs of the first memory and the second memory which function to subtract image information in the first memory from image information in the second memory,
- the factor .alpha..sub.1 being different from the factor .alpha..sub.2.
Dependencies are inferred from the claim text.