Abstract: Provided is a process including: obtaining video data; forming a transform matrix; dynamically forming a first modified quantization matrix; quantizing the first transform matrix with the modified quantization matrix; serializing the first quantized transform matrix to form a first sequence of values; compressing the first sequence of values with entropy coding to produce compressed video data; and forming a video bitstream that includes the compressed video data and a header, the header containing a parameter that instructs a decoder to decode the first block with a quantization matrix different from the modified quantization matrix.

Abstract: Provided is a process including: obtaining source and destination video data, the destination video data being a transformed version of the source video data; for a plurality of blocks in the given source frame, determining a respective source aggregate value that is based on a measure of central tendency of pixel values; for a plurality of blocks in the given destination frame, determining a respective destination aggregate value that is based on a measure of central tendency of pixel values; determining a plurality of differences between source and destination aggregate values; determining a frame aggregate value that is based on a measure of central tendency of the determined differences; and determining a measure of distortion of the destination video data based on the frame aggregate value.

Abstract: Provided is a process for compressing data that includes: obtaining data to be compressed; compressing the data with a first DCT compression algorithm to obtain a first DCT amplitude matrix; compressing the data with a second DCT compression algorithm to obtain a second DCT amplitude matrix, the second DCT compression algorithm compressing the data more than the first algorithm; modifying the second DCT amplitude matrix based on a value in the first DCT amplitude matrix.