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Frame permutation quantization (FPQ) is a new vector quantization technique using finite frames. In FPQ, a vector is encoded using a permutation source code to quantize its frame expansion. This means that the encoding is a partial ordering of the frame expansion coefficients. Compared to ordinary permutation source coding, FPQ produces a greater number of(More)
—Permutation codes are a class of structured vector quantizers with a computationally-simple encoding procedure based on sorting the scalar components. Using a codebook comprising several permutation codes as subcodes preserves the simplicity of encoding while increasing the number of rate–distortion operating points, improving the convex hull of operating(More)
—As a generalization of the subspace fitting, the union of subspaces fitting problem consists in finding an union of subspaces in some given family that best fits to the finite data. This report provides a detailed review of the main reference [4] about the existence of such optimal solution. Proofs for a series of unproved statements in the reference are(More)
Permutation codes are a class of structured vector quantizers with a computationally-simple encoding procedure. In this paper, we provide an extension that preserves the computational simplicity but yields improved operational rate-distortion performance. The new class of vector quantizers has a codebook comprising several permutation codes as subcodes.(More)
Using a step-graded (SG) buffer structure via metal-organic chemical vapor deposition, we demonstrate a high suitability of In0.5Ga0.5As epitaxial layers on a GaAs substrate for electronic device application. Taking advantage of the technique's precise control, we were able to increase the number of SG layers to achieve a fairly low dislocation density(More)
Permutation source codes are a class of structured vector quantizers with a computa-tionally-simple encoding procedure. In this thesis, we provide two extensions that preserve the computational simplicity but yield improved operational rate-distortion performance. In the first approach, the new class of vector quantizers has a codebook comprising several(More)
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