Abstract: Advanced digital compression systems, like the MPEG-standard, are entering the consumer market. However, the consumer acceptation of these technologies relies considerably on the possibility of substantial reduction of the implementation costs. In this paper we study a low-cost and high-quality embedded compression system for reducing the memory requirements of an MPEG-2 decoder with a factor of 4 - 6. The proposed embedded codec is based on a low-cost transform coding scheme and employs a modified feedforward coding mechanism to ensure a fixed compression factor. A novel quantization technique is developed, which prevents the error accumulation resulting from multiple encodings of the same pixel data. The decrease in image quality, caused by the embedded compression, is minimal (i.e. less than 1 dB) for MPEG-2 coded sequences at 4 - 9 Mbit/s. The proposed algorithm can also be successfully applied for memory reduction of MPEG- 2 encoders and H.263 codecs. !9
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