Forcing use of palette?

[Lancelotbronner]

Not sure if this is something that could be directly done by Oxipng or if anyone knows of a good companion tool for that but:

I have many images that are essentially a few colors with one irrelevant gradient, I'd really like to force use a palette and lose the gradient.

I'd suggest a --palette [arg] flag, disabled by default since its lossy. The arg could be the method for choosing which colors to keep. I'd use the default anyway so I don't have any to suggest.

[ace-dent]

Currently I use other tools to force a palette mode, then disable reductions in Oxipng. However, the default behaviour tends to yield optimal results. I personally use ImageMagick and/or PNGOUT as pre-processors.

[TPS]

@kornelski's pngquant is the most advanced tool I'm aware of for this, & it's indeed excellent. Given that, I'd prefer not bloating oxipng's codebase w/ something readily preprocessed this way.