Class WatermarkingConfig

configuration_utils.py:1423–1497

Class that holds arguments for watermark generation and should be passed into `GenerationConfig` during `generate`. See [this paper](https://arxiv.org/abs/2306.04634) for more details on the arguments. Accepts the following keys: - greenlist_ratio (`float`): Used fo

@dataclass
class WatermarkingConfig(BaseWatermarkingConfig):
    """
    Class that holds arguments for watermark generation and should be passed into `GenerationConfig` during `generate`.
    See [this paper](https://arxiv.org/abs/2306.04634) for more details on the arguments.

    Accepts the following keys:
        - greenlist_ratio (`float`):
            Used for watermarking. The ratio of "green" tokens used to the vocabulary size. Defaults to 0.25.
        - bias (`float`):
            Used with watermarking. The bias added to the selected "green" tokens' logits. Defaults to 2.0.
        - hashing_key (`int`):
            Hashing key used for watermarking. Defaults to 15485863 (the millionth prime).
        - seeding_scheme (`str`):
            Algorithm to use for watermarking. Accepts values:
                - "lefthash" (default): "green" tokens selection depend on the last token (Algorithm 2 from the paper)
                - "selfhash": "green" tokens selection depends on the current token itself (Algorithm 3 from the paper)
                    The downside of this scheme is that it considers all possible next tokens and can be slower than "lefthash".
        - context_width(`int`):
            The context length of previous tokens to use in seeding. Higher context length makes watermarking more robust.
    """

    def __init__(
        self,
        greenlist_ratio: Optional[float] = 0.25,
        bias: Optional[float] = 2.0,
        hashing_key: Optional[int] = 15485863,
        seeding_scheme: Optional[str] = "lefthash",
        context_width: Optional[int] = 1,
    ):
        self.greenlist_ratio = greenlist_ratio
        self.bias = bias
        self.hashing_key = hashing_key
        self.seeding_scheme = seeding_scheme
        self.context_width = context_width

    def validate(self):
        watermark_missing_arg_msg = (
            "Some of the keys in `watermarking_config` are defined incorrectly. `{key}` should be {correct_value}` "
            "but found {found_value}"
        )
        if self.seeding_scheme not in ["selfhash", "lefthash"]:
            raise ValueError(
                watermark_missing_arg_msg.format(
                    key="seeding_scheme",
                    correct_value="[`selfhash`, `lefthash`]",
                    found_value=self.seeding_scheme,
                ),
            )
        if not 0.0 <= self.greenlist_ratio <= 1.0:
            raise ValueError(
                watermark_missing_arg_msg.format(
                    key="greenlist_ratio",
                    correct_value="in range between 0.0 and 1.0",
                    found_value=self.seeding_scheme,
                ),
            )
        if not self.context_width >= 1:
            raise ValueError(