### How Robust Is Audio Perception in the Face of Deliberate Magnitude and Phase Distortions? (Part 3)

In the first post of this three-part series, I listed four points that I hope my readers will agree with at the end of this series. The second post addressed the first two points of the four. In this post, Part Three of the series, I will demonstrate the final two points: Phase distortions generally…

### How Robust Is Audio Perception in the Face of Deliberate Magnitude and Phase Distortions? (Part 2)

In this post I will demonstrate that dramatically different time domain waveforms can lead to virtually the same audio perception, and two waveforms with identical spectrograms can sound quite different.

### Spectral Analysis With the DFT

You may have encountered spectral analysis. The basic idea is to take a waveform, in our case an audio clip, and determine which frequency components are in it. Think of passing light through a prism and breaking it into a rainbow.

### Transforms for Video Compression, Part 3: The DCT and Why Transforming Is Valuable

The use of transforms in data compression algorithms is at least 40 years old. The goal of this three-part series of posts is to provide the mathematical background necessary for understanding transforms and to explain why they are a valuable part of many compression algorithms. I?m focusing on video since that?s my particular interest. Part…

### Transforms for Video Compression, Part 2: Matrix Representation and 2D Transforms

The use of transforms in data compression algorithms is at least 40 years old. The goal of this three-part series of posts is to provide the mathematical background necessary for understanding transforms and to explain why they are a valuable part of many compression algorithms. I?m focusing on video since that?s my particular interest. Part…

### Transforms for Video Compression, Part 1: Vectors, the Dot Product and Orthonormal Bases

The use of transforms in data compression algorithms is at least 40 years old. The goal of this three-part series of posts is to provide the mathematical background necessary for understanding transforms and to explain why they are a valuable part of many compression algorithms. I?ll focus on video since that?s my particular interest. Part…

### Power Measurements With the DFT

Many of the systems we work on here at Cardinal Peak employ analog-to-digital conversion in one form or another. It seems like almost invariably some analog signal needs to be digitized or “sampled.” Sampling is the process of periodically looking at an analog signal at some sample rate, and then converting each measured value into…