14 accepted papers
Coding delay has emerged as a significant obstacle to wider adoption of Higher Order Ambisonics (HOA), a promising flexible format employed in representation and coding of spatial audio. Low delay is critical in many applications, such as virtual reality, gaming, and online music performance, a good…
Bi-directional motion compensated prediction is widely utilized in video coding. Conventionally, the encoder searches for two motion vectors pointing to reference frames in both directions, and transmits these motion vectors to the decoder. Recognizing that the two reference frames are already avail…
Many virtual and augmented reality applications depend critically on efficient compression of spherical videos. Current approaches apply a projection geometry to map a spherical video onto the plane(s), wherein a standard codec can be used for compression. Video coders employ simple pixel copying fr…
Adaptive prediction is important in the compression of non-stationary signals, and a common remedy is to switch between appropriately designed prediction modes. This paper presents a near optimal procedure to design prediction modes for an adaptive compression system. The main challenges include: in…
In order to increase system capacity and transmission rates, fifth-generation (5G) cellular and 802.11ad/ay wireless systems will use millimeter wave frequencies (24GHz-70GHz), which require large antenna arrays and narrow beamforming to mitigate the impact of substantial path-loss. While narrow bea…
The MPEG-H 3D audio standard applies singular value decomposition (SVD) to the input higher order ambisonics data, then encodes each predominant (foreground) sound component independently using a standard core audio codec. The residual (background) signal is encoded in the ambisonic domain. This pap…
Scalable coding is potentially useful in content distribution over unreliable channels, as it enables meaningful reconstruction when the hierarchical bitstream is only partially received. However, its deployment in conjunction with predictive coding may result in considerable performance degradation…
This paper considers near optimal design of predictive compression system that accounts for packet loss over unreliable networks. Major challenges to address include, propagation of errors due to packet loss through the prediction loop, mismatch between statistics used for design and during operatio…
Conventional pixel-domain block matching temporal (inter) prediction is suboptimal, since it ignores the underlying spatial correlation. Hence in our recent research we proposed transform domain temporal prediction (TDTP), wherein spatially decorrelated transform coefficients are individually predic…
This paper extends the well-known source coding problem of multiple descriptions, in its general and basic setting, to analog source-channel coding scenarios. Encoding-decoding functions that optimally map between the (possibly continuous valued) source and the channel spaces are numerically derived…
Prediction is used in virtually all compression systems. When such a compressed signal is transmitted over unreliable networks, packet losses can lead to significant error propagation through the prediction loop. Despite this, the conventional design technique completely ignores the effect of packet…
While several real world signals, such as speech, image and sensor network data, are modeled as hidden Markov sources (HMS) for recognition and analysis applications, their typical compression exploits temporal correlations by modeling them as simple (non-hidden) Markov sources. However, the inheren…
Today's diverse data consumption devices and heterogeneous network conditions require content to be coded at different quality levels. Conventional scalable coding, which generates hierarchical layers that refine quality incrementally, introduces a performance penalty, as most sources are not succes…
Traditional temporal prediction relies on motion compensated pixel copying operations. Such per-pixel temporal prediction was shown in prior work to be sub-optimal since it ignores the underlying spatial correlation. Transform domain temporal prediction (TDTP) was thus proposed previously to first a…