WEEKLY RESEARCH GROUP MEETING PROGRESS REPORT FOR MONDAY 2ND FEBRUARY, 2009
WYNER‐ZIV CODEC IMPLEMENTATION SEE IMPLEMENTATION BLOCK DIAGRAM
BLOCK
COMMENTS
Block1. Video Frame splitter.
Using Histogram to determine key Frames (through conventional H264) and Wyner‐Ziv Frames. H264 CODEC (JM11.0) downloaded from the home page of the joint standard group. We treat key frames as a coarse‐scale representation of Wyner‐Ziv output and apply temporal Interpolation to them. The advanced temporal interpolation can be varied to use various GOP sizes, though this will increase delay and complexity. The virtual channel is used to estimate the channel bit error rates for lossless LPDC decoding. The Gaussian Channel is used. The variance is used for the approximation of acceptable output. Then blocks of large variance declared to be poorly‐MC and their positions are stored into a binary saliency map and transmitted to
Block 2 & 4 H264 Conventional codec
Block 5 Side Information Extraction
Block 6 Virtual channel model
Block 7a & 7b
Block3e
Block 3a-3c
Blocks 8a-8d
the encoder through the feedback channel (The required bandwidth is small ‐ 99bits/frame for QCIF sequence when MB = 16). For poorly‐MC frames we divide the coefficients into significant coefficients and non significant coefficients. This is mapped into saliency map. The sig coff. Threshold and MC threshold is used to increment the requested/required bits. This helps to choose the no. of bits to be transmitted first. This is the bits corresponding to the significant coefficients These are the DCT, quantization, S‐W encoder and buffer. This is the only things done at the encoder, therefore keeping the encoder light (Low Overhead). These are the decoder blocks. 8d includes the motion compensation and rate distortion estimation and is computationally intensive. Th. Motion compensation threshold is used to stop the iterations. We can use the variance of acceptable output or we can use a number of iterations.
SIMULATION RESULTS The results have been plotted on the discover graph.