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Video Compression and Decompression
A video compression and decompression processor is used to compress and
decompress video data. The video compression and decompression processor
contains multiple stages for compression and decompression. The stages include
forward discrete cosine transformation and inverse discrete cosine
transformation, quantization and inverse quantization, ZigZag and Zero run-
length encoding and decoding, and motion estimation and compensation.
Audio Compression: MPEG-2 uses adaptive pulse code modulation (ADPCM)
to sample the audio signal. The method takes a difference between the actual
sample value and predicted sample value. The difference is then encoded by a 4-
bit value or 8-bit value depending upon the sample rate.
Analog to Digital Converter: The ADC takes inputs from the video switch and
converts the amplitude of a sampled analog signal to either an 8-bit or 16-bit
digital value.
