How to interpret data from I2C Color sensor?

Hi there,
I’m new to Arduino and Grove and as a personal project, I’m building an automated robot able to follow a line, avoid obstacles and ideally manage line crossing by following colored indicators.
So I recently added an I2C color sensor V2.0 and tried one simple example (tcs34725). I was surprised to get some ackward results by executing :
tcs.getRawData(&r, &g, &b, &c);
What are the range values for r, g and b ? How to convert them to classical range [0, 255] ?

Thanks for your help,

The type of r,g,b is int16_t. I think you can simply map linearly to 255.