1. Fine Grained Scalable Video Coding For Streaming Multimedia Communications Zahid Ali 2 April 2006

2. Introduction Channel EncoderServer Decoder Configuration for Streaming Raw Video Network bandwidth, Price per transmitted and stored bit decreasing Why Compression? Internet throughput rates are insufficient to handle uncompressed video in real time Efficient use of transmission and storage resources (more attractive) All users don’t have same processing capabilities Solution: Scalable Video Coding

3. Introduction (Contd)  Scalable Video Coding (SVC) in Mpeg2 SNR, temporal and spatial scalability Base and enhancement layers  Drawback Enhancement layer needs to be received completely for decoding

4. Introduction (Cont) Mpeg2 enhancement layer just changes the non scalable video coding method from one stair curve to 2 stair curve

5. FGS with bit-plane coding  FGS in Mpeg4  Fine Granular Scalability  3 techniques for FGS framework Bit-plane coding of DCT coefficients Wavelet coding of image residue Matching pursuit coding of image residue  Objective of FGS coding is to optimize the video quality over a given bit rate range instead of at a given bit rate

6. FGS with bit-plane coding (Cont)  Encodes a sequence as a base layer and enhancement layer.  Base layer coded as non-scalable  Enhancement layer is coded as the difference between original and reconstructed picture using bit plane coding of DCT coefficients

7. Bit Plane Coding  64 absolute values for each 8 by 8 DCT block are zigzag ordered into an array  Bit plane of a block is an array of 64 bits, taken one from each absolute value of the DCT coefficients at the same significant position 10,0,6,0,0,3,0,2,2,0,0,2,0,0,1,0,………..,0,0 1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,……………..,0,0(MSB) 0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,……………..,0,0(MSB-1) 1,0,1,0,0,1,0,1,1,0,0,1,0,0,0,0,……………..,0,0(MSB-2) 0,0,0,0,0,1,0,0,0,0,0,0,0,0,1,0,……………..,0,0(MSB-3)

8. FGS Scalability Structure Base Layer IBPB Enhancement Layer At the Sender Base Layer IBPB Enhancement Layer At the Streaming Server Base Layer IBPB Enhancement Layer At the Decoder Encoder only needs to know the bandwidth range Streaming server streams a portion of enhancement layer depending on the available bandwidth

9. SNR FGS Base Layer and Enhancement layer encoder FDCT Encode each bit plane Quantizer Rescale Encode Coefficients Enhancement layer Base layer

10. SNR FGS Base Layer and Enhancement layer Decoder Decode Coefficients IDCT Rescale Decode bit plane IDCT Base layer Enhancement layer Base layer Enhancement layer