## frequency_compression.jpg

The image is a diagram illustrating frequency compression in audio processing, specifically focusing on how certain frequencies are altered when an input signal (IN) is processed into an output signal (OUT). The diagram uses color gradients and labels to explain the concept.

- **Title**: At the top of the image, there's a title that reads "Figure 7: How Sound/Power compression changes audio bandwidth." This indicates that the figure explains how sound or power compression affects the bandwidth of audio signals.
  
- **Axes**:
  - The horizontal axis is labeled as "Frequency," indicating it represents different frequencies on an audio spectrum. The frequency range spans from left to right, with lower frequencies on the left and higher frequencies towards the right.

- **Color Gradient**:
  - The color gradient at the bottom of the diagram transitions from yellow (representing low frequencies) through green, blue, purple, and finally to red (representing high frequencies). This visual representation helps in understanding how different frequency ranges are affected by compression.
  
- **Labels**:
  - "IN" is written on the left side above a color gradient that represents an input signal. The colors transition from yellow to red as you move right along this gradient, indicating various frequency components of the original audio signal.
  - "OUT" is written below another color gradient representing the output signal after compression. This gradient also transitions from yellow through green, blue, purple, and red but shows a different pattern compared to the IN gradient.

- **Key Features**:
  - A dashed vertical line labeled as "cut-off frequency" divides the frequency spectrum into two parts: frequencies below this point are considered audible (colored in shades of yellow, green, and blue), while those above it are not audibly perceived by humans (colored red).
  - The term "bandwidth limit" is written at the top right corner, indicating a specific range where compression occurs. Frequencies beyond this limit are compressed or altered.
  
- **Arrows**:
  - An arrow labeled "frequency compression" points from the IN gradient to the OUT gradient on the right side of the diagram, showing how frequencies in the output signal have been shifted or reduced compared to those in the input.

This detailed description should help a student understand the visual representation and concept being depicted in the image.

This description was generated automatically from image files by a local LLM, and thus, may not be fully accurate. Please feel free to ask questions if you have further questions about the nature of the image or its meaning within the presentation.