How Well Does the Shannon Codebook Compress ?
نویسنده
چکیده
| We consider the problem of describing the exact compression performance of a classical Shannon random codebook, for lossy source coding at a xed distortion level. For a memoryless source with a nite alphabet and a single-letter distortion measure, we address the following questions: (1) Are all random codebooks equally good? (2) What is the pointwise redundancy of a typical random codebook? (3) Is there a cost for universality in pointwise redun-dancy? (4) Is the overall best codebook better than the best random codebook? We ooer answers for the rst three questions, and a hint of an answer for the last one.
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