In video applications, digital encoding techniques are frequently associated to the use of compression algorithms. The rate of compression depends on the quality/bit rate requirements specific to each application. In TV broadcast/distribution applications, compression algorithms such as the MPEG2 standard allow economies in transmission bandwidth, while providing a service with a quality simila...

In general, a variable rate coder can obtain the same speech quality as a fixed rate coder, while reducing the average bit rate. We have developed a variable-rate multimodal speech coder with an average bit rate of 3 kb/s for a speech activity factor of 80% and quality comparable to the GSM full rate coder. The coder has four coding modes and uses a robust classification method involving the pi...

We introduce a scheme for optimally allocating a variable number of bits per LSH hyperplane. Previous approaches assign a constant number of bits per hyperplane. This neglects the fact that a subset of hyperplanes may be more informative than others. Our method, dubbed Variable Bit Quantisation (VBQ), provides a datadriven non-uniform bit allocation across hyperplanes. Despite only using a frac...

We develop a custom Bit Error Rate test bench based on Altera’s Stratix II GX transceiver signal integrity development kit, demonstrate it on point-to-point serial optical link with data rate up to 5 Gbps, and compare it with commercial stand alone tester. The 8B/10B protocol is implemented and its effects studied. A variable optical attenuator is inserted in the fibre loop to induce transmissi...

Variable-bit-rate (VBR) encoding is known to provide a more consistent visual quality compared to constant-bit-rate (CBR) encoding. However, the resultant bit-rate variations greatly complicated the allocation of disk and network bandwidth in a video-on-demand system. This paper investigates a new scheduling algorithm with monotonic-decreasing rate allocations for scheduling disk retrievals and...

A low delay and low complexity speech coder based on Multimode Tree Coding is proposed. In our Multimode Tree Coder, a simple mode classification method along with frame energy are used to classify the input speech frames into five different modes. Each mode is coded at a suitable bit-rate using a Tree coder with computationally efficient perceptual error pre-weighting and post-weighting filter...

This paper proposed a technique of bit-rate control for video streaming over constant bit-rate communication channel, where the MPEG-2, standard variable bit-rate (VBR), is adapted to be used as a constant bitrate (CBR). The target image quality and output rate of the video encoder is controlled by feedback based on the buffer level. A CBR transport over networks, result is a good performance c...