Overview
Introduction
This tool scans every pixel of an uploaded PNG and reports its colors converted to NTSC YIQ, the luma/chrominance color space classic analog color television broadcasts used.
It's a useful way to see how an image's colors break down into brightness versus color-direction information the way a 1950s-era TV signal would have encoded them.
What Is PNG to YIQ Colors Converter?
A client-side color analysis tool that decodes a PNG, tallies its distinct RGBA colors, and converts each one to YIQ using the standard NTSC linear transform.
The output is a readable plain-text report rather than raw pixel data, capped at the 256 most frequent colors for readability.
How PNG to YIQ Colors Converter Works
Every pixel's exact RGBA value is counted in a frequency map; the resulting unique colors are sorted from most to least common.
Each color's Y (luma) is computed as a weighted sum of R, G, and B matching standard perceptual luminance, while I and Q are computed from separate fixed linear combinations of R, G, and B representing in-phase and quadrature chrominance.
When To Use PNG to YIQ Colors Converter
Use it to explore how an image's brightness and color information separate under a historical broadcast color model.
It's also useful for educational purposes when explaining how analog color TV encoded color on top of a black-and-white signal.
Often used alongside PNG to YCbCr Colors Converter, PNG to HSL Colors Converter and PNG to LCH Colors Converter.
Features
Advantages
- Runs entirely client-side; your image is never uploaded to a server.
- Groups identical colors together with counts, rather than dumping every pixel individually.
- Uses the standard, well-documented NTSC YIQ linear transform constants.
Limitations
- This is a mathematical color-space transform for reference and educational purposes, not a simulation of actual analog broadcast signal artifacts or bandwidth limiting.
- The report caps out at the 256 most frequent unique colors; images with huge color diversity (like photos) will have many rarer colors omitted.
Examples
Best Practices & Notes
Best Practices
- Use this to understand the relationship between brightness and color direction in an image, not as a literal broadcast-accurate simulation.
- Compare against the YCbCr converter to see how different broadcast-era color spaces treat the same source colors differently.
Developer Notes
The YIQ math is a pure, individually-exported function (rgbToYiq) implementing the standard NTSC linear transform (Y = 0.299R + 0.587G + 0.114B, I = 0.596R - 0.274G - 0.322B, Q = 0.211R - 0.523G + 0.312B), directly unit-testable against known reference colors.
PNG to YIQ Colors Converter Use Cases
- Educational exploration of how analog color television encoded color
- Comparing luma/chrominance breakdowns across different broadcast-era color spaces
- Spot-checking how a specific color's brightness and chrominance separate under YIQ
Common Mistakes
- Confusing YIQ with YUV or YCbCr: they're related but use different derivation constants and aren't numerically interchangeable.
- Expecting I and Q to stay within 0-255 the way Y does; they're signed values that can go negative.
Tips
- Focus on the Y column first if you mainly care about relative brightness across colors.
- Try this on the same image as the YCbCr converter to compare the two broadcast-era color spaces side by side.