Perfusion Angiography in Acute Ischemic Stroke

Figure 4

Illustration of the Gamma fitting process to recover two components for 4 different combinations of noise and overlap. Components and   are shown in blue and red and were estimated using the EM-based Gamma-variate fitting (Section 2.5) based on the noisy input depicted by the dashed line.

(a) SNR = 45, overlap = 7.5%

(b) SNR = 4.5, overlap = 7.5%

(c) SNR = 16, overlap = 57.5%

(d) SNR = 4.5, overlap = 62.5%