rgb2gray — Convert an RGB image to grayscale using luminance weights.

rgb2gray(RGB) converts an MxNx3 truecolor image to an MxN grayscale image with the standard luminance weights.

How rgb2gray works

• Accepts MxNx3 truecolor images.
• Uses weights 0.2989, 0.5870, and 0.1140 for red, green, and blue.
• Preserves uint8, uint16, single, and double image class metadata on host tensors.

Example

Convert RGB To Gray

I = rgb2gray(RGB);

Expected output:

% I is MxN

Related Image functions

Open-source implementation

Unlike proprietary runtimes, every RunMat function is open-source. Read exactly how rgb2gray works, line by line, in Rust.

• View rgb2gray.rs on GitHub
• Learn how the runtime works
• Found a bug? Open an issue with a minimal reproduction.

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