One converter for every raster format — PNG, JPG, WebP, BMP, GIF. The engine routes each image to the right pipeline: monochrome specialist for black-and-white, shared-boundary color engine with gradient detection for everything else.
Black-and-white line art and colorful logos are different problems. B&W wants a monochrome tracer with optimal thresholding; color wants perceptual clustering, shared boundaries and gradient fitting. WizVector detects which kind of image you uploaded and routes it to the specialist — the metrics line on your job tells you which engine ran. That's why quality stays high across input types instead of being great at one and terrible at the other.