Final Exam 2 Solutions

If one uses previous previous frame fn 2 in the base

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: accurate and hence the coding efficiency will be lower. But this approach does not cause any mismatch error in the receiver if it only receives the base layer. There are multiple reasons to cause error propagation, including temporal prediction, spatial prediction and variable length coding. Some encoding tools that can suppress error propagation includes 1) periodic insertion of intra-blocks (or intra-frames), 2) insertion of synchronization markers; 3) multiple description coding. d) (20 pt) Write a Matlab code that implements coding of a P-frame in a block-based hybrid video coder. For simplicity, use 8x8 blocks for both prediction and DCT coding, and consider the coding of Y-pixels only. For each block, you may decide to code it in either I-Mode (predict this block from previously coded samples in this frame using one of a few intra-prediction modes) or P-Mode (predict from a best matching block in the previous frame). For either mode, you perform DCT on the prediction error block, quantize the DCT coefficients using a preset QP and quantization matrix QMatrix, code the mode and the quantized DCT coefficients using an entropy coding method. Denote the frame to be coded by CurrentFrame, the previous frame used for temporal prediction by PrevFrame. Your program should write the resulting bits for successive blocks into a file outfile. Your program should also compute and save the reconstructed frame in QuantizedFrame. Also use Width and Height to denote the width and height of a frame and assume both the width and height are dividable by 8. Furthermore, assume the following functions are available (i.e. can be called by your matlab code). Your program can call these functions as well as other MATLAB functions and functions defined by yourself. function [mvh, mvv,PredictedMBlock]=MotionEstimation(bx, by, MBlock,PrevFrame): finds the best matching block for a...
View Full Document

This document was uploaded on 03/12/2014 for the course EL 6123 at NYU Poly.

Ask a homework question - tutors are online