Downscaled inverses for M-channel lapped transforms
نویسندگان
چکیده
Compressed images may be decompressed for devices using di erent resolutions. Full decompression and rescaling in space domain is a very expensive method. We studied downscaled inverses where the image is decompressed partially and a reduced inverse transform is used to recover the image. We studied the design of fast inverses, for a given forward transform. General solutions are presented for M -channel FIR lter banks of which block and lapped transforms are a subset.
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Fast downscaled inverses for images compressed with M-channel lapped transforms
Compressed images may be decompressed and displayed or printed using different devices at different resolutions. Full decompression and rescaling in space domain is a very expensive method. We studied downscaled inverses where the image is decompressed partially, and a reduced inverse transform is used to recover the image. In this fashion, fewer transform coefficients are used and the synthesi...
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