TY - JOUR
T1 - Fast and accurate computation of system matrix for area integral model-based algebraic reconstruction technique
AU - Zhang, Shunli
AU - Zhang, Dinghua
AU - Gong, Hao
AU - Ghasemalizadeh, Omid
AU - Wang, Ge
AU - Cao, Guohua
N1 - Publisher Copyright:
© 2014 Society of Photo-Optical Instrumentation Engineers.
PY - 2014/11/1
Y1 - 2014/11/1
N2 - Iterative algorithms, such as the algebraic reconstruction technique (ART), are popular for image reconstruction. For iterative reconstruction, the area integral model (AIM) is more accurate for better reconstruction quality than the line integral model (LIM). However, the computation of the system matrix for AIM is more complex and time-consuming than that for LIM. Here, we propose a fast and accurate method to compute the system matrix for AIM. First, we calculate the intersection of each boundary line of a narrow fan-beam with pixels in a recursive and efficient manner. Then, by grouping the beam-pixel intersection area into six types according to the slopes of the two boundary lines, we analytically compute the intersection area of the narrow fan-beam with the pixels in a simple algebraic fashion. Overall, experimental results show that our method is about three times faster than the Siddon algorithm and about two times faster than the distance-driven model (DDM) in computation of the system matrix. The reconstruction speed of our AIM-based ART is also faster than the LIM-based ART that uses the Siddon algorithm and DDM-based ART, for one iteration. The fast reconstruction speed of our method was accomplished without compromising the image quality.
AB - Iterative algorithms, such as the algebraic reconstruction technique (ART), are popular for image reconstruction. For iterative reconstruction, the area integral model (AIM) is more accurate for better reconstruction quality than the line integral model (LIM). However, the computation of the system matrix for AIM is more complex and time-consuming than that for LIM. Here, we propose a fast and accurate method to compute the system matrix for AIM. First, we calculate the intersection of each boundary line of a narrow fan-beam with pixels in a recursive and efficient manner. Then, by grouping the beam-pixel intersection area into six types according to the slopes of the two boundary lines, we analytically compute the intersection area of the narrow fan-beam with the pixels in a simple algebraic fashion. Overall, experimental results show that our method is about three times faster than the Siddon algorithm and about two times faster than the distance-driven model (DDM) in computation of the system matrix. The reconstruction speed of our AIM-based ART is also faster than the LIM-based ART that uses the Siddon algorithm and DDM-based ART, for one iteration. The fast reconstruction speed of our method was accomplished without compromising the image quality.
KW - Siddon algorithm
KW - algebraic reconstruction technique
KW - area integral model
KW - computed tomography
KW - image reconstruction
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U2 - 10.1117/1.OE.53.11.113101
DO - 10.1117/1.OE.53.11.113101
M3 - Article
AN - SCOPUS:84925813162
SN - 0091-3286
VL - 53
JO - Optical Engineering
JF - Optical Engineering
IS - 11
M1 - 113101
ER -