In the docs for FFV1 there's a parameter
-context, which can be set to 'small' or 'large'. That's all the documentation I can find.
While I'm at it, what are the relative benefits of the different encoders: Golomb Rice vs Range Coder?
The coder here refers to the process used for entropy coding the error residuals. The context size sets how many neighbouring residuals are considered in this process.
As to the relative benefits, have no particular experience here, but since this is a lossless process, the tradeoff will be between time, size and resource use. This latter question is better suited for https://dsp.stackexchange.com/