title: Toward Optimal Computation of Ultrasound Image Reconstruction Using CPU and GPU.
abstract: An ultrasound image is reconstructed from echo signals received by array elements of a transducer. The time of flight of the echo depends on the distance between the focus to the array elements. The received echo signals have to be delayed to make their wave fronts and phase coherent before summing the signals. In digital beamforming, the delays are not always located at the sampled points. Generally, the values of the delayed signals are estimated by the values of the nearest samples. This method is fast and easy, however inaccurate. There are other methods available for increasing the accuracy of the delayed signals and, consequently, the quality of the beamformed signals; for example, the in-phase (I)/quadrature (Q) interpolation, which is more time consuming but provides more accurate values than the nearest samples. This paper compares the signals after dynamic receive beamforming, in which the echo signals are delayed using two methods, the nearest sample method and the I/Q interpolation method. The comparisons of the visual qualities of the reconstructed images and the qualities of the beamformed signals are reported. Moreover, the computational speeds of these methods are also optimized by reorganizing the data processing flow and by applying the graphics processing unit (GPU). The use of single and double precision floating-point formats of the intermediate data is also considered. The speeds with and without these optimizations are also compared.
authors.affiliation: National Electronics and Computer Technology Center, Pathumthani 12120, Thailand. udomchai.techavipoo@nectec.or.th.
authors.forename: Udomchai
authors.initials: U
authors.lastname: Techavipoo
authors.affiliation: Department of Electrical Engineering, Faculty of Engineering, Kasetsart University, Bangkok 10900, Thailand. fengdcw@ku.ac.th.
authors.forename: Denchai
authors.initials: D
authors.lastname: Worasawate
authors.affiliation: Department of Electrical Engineering, Faculty of Engineering, Kasetsart University, Bangkok 10900, Thailand. wittawat_1@yahoo.com.
authors.forename: Wittawat
authors.initials: W
authors.lastname: Boonleelakul
authors.affiliation: National Electronics and Computer Technology Center, Pathumthani 12120, Thailand. rachaporn.keinprasit@nectec.or.th.
authors.forename: Rachaporn
authors.initials: R
authors.lastname: Keinprasit
authors.affiliation: National Electronics and Computer Technology Center, Pathumthani 12120, Thailand. treepop.sunpetchniyom@nectec.or.th.
authors.forename: Treepop
authors.initials: T
authors.lastname: Sunpetchniyom
authors.affiliation: Department of Information Processing, Tokyo Institute of Technology, Tokyo 152-8552, Japan. sugino.n.aa@m.titech.ac.jp.
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Sugino
authors.affiliation: National Electronics and Computer Technology Center, Pathumthani 12120, Thailand. pairash@nstda.or.th.
authors.forename: Pairash
authors.initials: P
authors.lastname: Thajchayapong
keywords: CUDA; array transducer; dynamic receive beamforming; graphics processing unit; image reconstruction; ultrasound imaging