Improved Chen-Smith image coder
نویسندگان
چکیده
An image compression system based on transform coding and zonal sampling is presented. It is based on the wellknown Chen-Smith coder, but with an improved technique for transform coefficient quantization and the replacement of the discrete cosine transform (DCT) by the lapped orthogonal transform (LOT). The system leads to signal-to-noise ratios that are from 1.5 to 2.0 dB above those obtained with the standard JPEG algorithm, for a wide variety of test images and compression rates.
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عنوان ژورنال:
- J. Electronic Imaging
دوره 4 شماره
صفحات -
تاریخ انتشار 1993