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vllm.multimodal.media.video

VideoMediaIO

Bases: MediaIO[tuple[NDArray, dict[str, Any]]]

Configuration values can be user-provided either by --media-io-kwargs or by the runtime API field "media_io_kwargs". Ensure proper validation and error handling.

Source code in vllm/multimodal/media/video.py
class VideoMediaIO(MediaIO[tuple[npt.NDArray, dict[str, Any]]]):
    """Configuration values can be user-provided either by --media-io-kwargs or
    by the runtime API field "media_io_kwargs". Ensure proper validation and
    error handling.
    """

    @classmethod
    def merge_kwargs(
        cls,
        default_kwargs: dict[str, Any] | None,
        runtime_kwargs: dict[str, Any] | None,
    ) -> dict[str, Any]:
        merged = super().merge_kwargs(default_kwargs, runtime_kwargs)
        # fps and num_frames interact with each other, so if either is
        # overridden at request time, wipe the other from defaults to
        # avoid unintuitive cross-field interactions.
        if runtime_kwargs:
            if "num_frames" in runtime_kwargs and "fps" not in runtime_kwargs:
                merged.pop("fps", None)
            elif "fps" in runtime_kwargs and "num_frames" not in runtime_kwargs:
                merged.pop("num_frames", None)
        return merged

    def __init__(
        self,
        image_io: ImageMediaIO,
        num_frames: int = 32,
        **kwargs,
    ) -> None:
        super().__init__()

        self.image_io = image_io
        self.num_frames = num_frames
        # `kwargs` contains custom arguments from
        # --media-io-kwargs for this modality, merged with
        # per-request runtime media_io_kwargs via merge_kwargs().
        # They can be passed to the underlying
        # media loaders (e.g. custom implementations)
        # for flexible control.

        # Allow per-request override of video backend via kwargs.
        # This enables users to specify a different backend than the
        # global VLLM_VIDEO_LOADER_BACKEND env var, e.g.:
        #   --media-io-kwargs '{"video": {"video_backend": "torchcodec"}}'
        video_loader_backend = (
            kwargs.pop("video_backend", None) or envs.VLLM_VIDEO_LOADER_BACKEND
        )
        self.kwargs = kwargs
        self.video_loader = VIDEO_LOADER_REGISTRY.load(video_loader_backend)

    def load_bytes(self, data: bytes) -> tuple[npt.NDArray, dict[str, Any]]:
        return self.video_loader.load_bytes(
            data, num_frames=self.num_frames, **self.kwargs
        )

    def load_base64(
        self, media_type: str, data: str
    ) -> tuple[npt.NDArray, dict[str, Any]]:
        if media_type.lower() == "video/jpeg":
            load_frame = partial(
                self.image_io.load_base64,
                "image/jpeg",
            )

            return np.stack(
                [np.asarray(load_frame(frame_data)) for frame_data in data.split(",")]
            ), {}

        return self.load_bytes(base64.b64decode(data))

    def load_file(self, filepath: Path) -> tuple[npt.NDArray, dict[str, Any]]:
        with filepath.open("rb") as f:
            data = f.read()

        return self.load_bytes(data)

    def encode_base64(
        self,
        media: npt.NDArray,
        *,
        video_format: str = "JPEG",
    ) -> str:
        video = media

        if video_format == "JPEG":
            encode_frame = partial(
                self.image_io.encode_base64,
                image_format=video_format,
            )

            return ",".join(encode_frame(Image.fromarray(frame)) for frame in video)

        msg = "Only JPEG format is supported for now."
        raise NotImplementedError(msg)