Table 1. Video Encoder Description
Block Name Block Description Block Function
Pre-Proc. Pre-Processing If necessary, the Pre-Proc. Block converts the input video format to YUV 4:2:0.
Video Buffer Video Buffer Encoder stores the compressed data for processing. DCT Discrete Cosine Transform DCT transformation decomposes each input block into a
series of waveforms with a specific spatial frequency.
Outputs an 8x8 block of horizontal and vertical frequency coefficients.
Q Quantization Quantization block uses the psychovisual characteristics to eliminate the unimportant DCT coefficients, high frequency coefficients.
IQ Inverse Quantization IQ computes the inverse quantization matrix by multiplying the quantized DCT with the quantization table.
IDCT Inverse Discrete Cosine
IDCT computes the original input block. Errors are expected due to quantization.
Frame Buffer Frame Buffer Memory required for video processing, typically 3 frames stored.
ME Motion Estimation ME uses a scheme with fewer search locations and fewer pixels to generate motion vectors indicating the directions of the moving images.
MC Motion Compensation MC block increases the compression ratio by removing the redundancies between frames.
VLC Variable Length Coding Lossless VLC coding reduces the bit rate by sending shorter codes for common pairs (number of zeros and number of non-zeros) and longer codes for less common pairs.
Rate Cont. Rate Control Control the bit rate by changing the quantization rules, for example using fewer bits per DCT coefficient.
Buffer Buffer Output data buffer