Arbitrary-ratio image resizing using fast DCT of composite length for DCT-based transcoder.
We propose a fast arbitrary-ratio image resizing method for transcoding of the compressed images. The downsizing process in the discrete cosine transform (DCT) domain can be implemented by truncating high-frequency coefficients, whereas the upsizing process is implemented in the DCT domain by padding zero coefficients to the high-frequency part. The proposed method combines a fast inverse and forward DCT of composite length for arbitrary-ratio upsizing or downsizing. According to the resizing ratio, truncating the high-frequency coefficients and padding zeros are appropriately considered by combining the inverse DCT and forward DCT. The proposed method shows a good peak signal-to-noise ratio and less computational complexity compared with the spatial-domain and previous DCT-domain image resizing methods.
Park
Young Seo
YS
Department of Electrical Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Korea. young@athena.kaist.ac.kr
Park
Hyun Wook
HW
D000465:Algorithms; D001185:Artificial Intelligence; D003195:Computer Communication Networks; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D016247:Information Storage and Retrieval / Q000379:methods*; D009716:Numerical Analysis, Computer-Assisted; D012815:Signal Processing, Computer-Assisted; D014741:Video Recording / Q000379:methods*