Weekly Projects, November 7
At this first weekly project session, we shall have only a few projects,
at later sessions we shall have many more.
Note that it is not the intention that everyone does every project.
Rather, select a single project at a time and concentrate on that. You
are also most welcome to come up with alternative project ideas
yourself, as long as they are related to the issues we are
currently
discussing.
Project 1
For this project (and later projects), is it necessary to understand
the format of the files in the Sources directory and
how they represent sampled signals. Familiarize yourself with the
format of the files (possibly using information found on the internet to
understand the headers of .pbm, .pgm and .wav files). Which scalar quantizer was used to quantize avis.wav and bbc.wav?
Try compressing images and
sound by simply throwing away most of the samples. Can you observe aliasing
effects?
Project 2
For this project (and later projects), is it necessary to understand
the format of the files in the Sources directory and
how they represent sampled signals. Familiarize yourself with the
format of the files (possibly using information found on the internet to
understand the headers of .pbm, .pgm and .wav files). Which scalar quantizer was used to quantize avis.wav and bbc.wav?
This project is meant to provide a feeling for the perceptual meaning
of SNR and PSNR values. Take images and sound files and perturbate each
sample by an independently randomly chosen value in some range. Alternatively,
"perturbate" the file by applying various public domain lossy codecs.
Compute the SNR of
the perturbed files, relative to the original ones and view/listen to the
perturbed files. How does the distortion measure correspond to
the human perception of distortion?