[Study of continuous wavelet transform on detecting and enhancing blood vessel in DSA image]

Low contrast is the shortcoming of the image in Digital Subtraction Angiography. This paper presents a new approach for the enhancement of blood volume in DSA image. The wavelet transform was applied to detect blood edges, and then the image contrast was enhanced by the method of contrast stretched. Because the continuous wavelet adopted in this study can detect gray variety in different orientations, the blood vessel edge detected by this algorithm is more precise and complete. Moreover, because the module of image noise by wavelet transform is smaller, the algorithm can protrude blood vessel but restrain noise in background. The processing result showed a very good optical effect of 3 dimensional objects for medical diagnoses.