Channel optimized predictive vector quantization

Power series quantization for noisy channels

“…Channel-optimized quantization, where the channel is taken into account directly in the quantizer training, is a more systematic approach than RVQ, since the source and channel coders are co-optimized. Channel-optimized quantization also provides better performance than RVQ [17], [18].…”

“…Predictive VQ schemes have been adapted to noisy channels by using prediction that does not fully exploit the source correlation, and by a safety-net approach where two sub-codebooks are used, one predictorbased and one without predictor [11]. A channel-optimized PVQ (COPVQ) with linear predictor and optimal encoder index search strategy was designed in [18]. Differently from [22] and [23], this scheme is not limited to usage of the same codebooks on the encoder and decoder side.…”

“…Differently from [22] and [23], this scheme is not limited to usage of the same codebooks on the encoder and decoder side. It was shown in [18] that the presented method outperforms COVQ, PVQ with index assignment, and FSVQ for noisy channels [24], [25]. The COPVQ scheme in [18] is however limited by its linear predictor, and cannot handle nonlinear correlation.…”

“…An optimal lowcomplexity COPSQ encoder index search strategy is proposed, and several off-line codebook optimization procedures are derived. The proposed system generalizes [18] to sources with nonlinear memory. Though our aim is to present a scheme applicable to general sources and general discrete memoryless channels, we evaluate COPSQ for coding of line spectrum frequencies (LSF) [27], and binary symmetric and additive white Gaussian noise (AWGN) channels.…”

Multistage vector quantizer optimization for packet networks

“…In [5], a block shuffling scheme for whole video blocks was suggested to help isolate erroneous blocks at the receiver, facilitating the process of error concealment. Examples from speech coding can be found in [6]- [8]. When information concerning whole video macroblocks or whole speech frames are interleaved for the purpose of distributing the effect of losses, then this scheme is called block interleaving (for video or image coding) or frame interleaving (for speech and audio coding).…”