Arbitrary-ratio image resizing using fast DCT of composite length for DCT-based transcoder.

Young Seo Park; Hyun Wook Park

doi:10.1109/tip.2005.863117

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Arbitrary-ratio image resizing using fast DCT of composite length for DCT-based transcoder.

Young Seo Park·Hyun Wook Park

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Abstract

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.

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Young Seo Park, Hyun Wook Park. 2006. Arbitrary-ratio image resizing using fast DCT of composite length for DCT-based transcoder.. https://doi.org/10.1109/tip.2005.863117

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