Computer Science 1033A/B Lecture Notes - Lecture 11: Alger Hiss, Hertz

• School: Western University
• Department: Computer Science
• Course: Computer Science 1033A/B
• Professor: Laura Reid

Document Summary

4 strategies: reduce number of samples (sample rate) Go from 44 khz to 22 khz. Cutting sample number in half will also cut file size in half: reduce bit depth (sample size) Go from 16 bit to 8 bit. Cutting bit depth in half also cuts file size in half: reduce channels. Changing from stereo to mono will cut file size in half: compress using appropriate codec. File formats that use lossless codecs are not very common. Common file formats that are uncompressed : wav (common, aiff, cdda standard for cds, 2 channels. Modify volume amplify, fades, envelope, normalize: normalization: scans files for avg level and adjusts volume to match. Noise reduction: hiss reduction noise within a given frequency range, reduction/removal unusual difference removed from waveform. Need longer audio than w/hiss bc need to analyze to find norm. Special effects echo, changing pitch of a portion.