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Image Scaler

renderkit.processing.scaler.ImageScaler

Utility class for image scaling using OpenImageIO.

Source code in src/renderkit/processing/scaler.py 
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class ImageScaler:
    """Utility class for image scaling using OpenImageIO."""

    @staticmethod
    @staticmethod
    def scale_buf(
        buf,
        width: int,
        height: int,
        filter_name: str = "lanczos3",
    ):
        """Scale an OIIO ImageBuf without converting to NumPy."""
        try:
            import OpenImageIO as oiio
        except ImportError as e:
            raise RuntimeError("OpenImageIO library not available.") from e

        spec = buf.spec()
        src_buf = buf
        if spec.format != oiio.FLOAT:
            float_spec = oiio.ImageSpec(spec.width, spec.height, spec.nchannels, oiio.FLOAT)
            float_buf = oiio.ImageBuf(float_spec)
            if not oiio.ImageBufAlgo.copy(float_buf, buf):
                raise RuntimeError(f"OIIO copy to float failed: {oiio.geterror()}")
            src_buf = float_buf

        dst_buf = oiio.ImageBuf(oiio.ImageSpec(width, height, spec.nchannels, oiio.FLOAT))
        if not oiio.ImageBufAlgo.resize(dst_buf, src_buf, filtername=filter_name):
            raise RuntimeError(f"OIIO resize failed: {oiio.geterror()}")

        return dst_buf

scale_buf(buf, width, height, filter_name='lanczos3') staticmethod

Scale an OIIO ImageBuf without converting to NumPy.

Source code in src/renderkit/processing/scaler.py 
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@staticmethod
@staticmethod
def scale_buf(
    buf,
    width: int,
    height: int,
    filter_name: str = "lanczos3",
):
    """Scale an OIIO ImageBuf without converting to NumPy."""
    try:
        import OpenImageIO as oiio
    except ImportError as e:
        raise RuntimeError("OpenImageIO library not available.") from e

    spec = buf.spec()
    src_buf = buf
    if spec.format != oiio.FLOAT:
        float_spec = oiio.ImageSpec(spec.width, spec.height, spec.nchannels, oiio.FLOAT)
        float_buf = oiio.ImageBuf(float_spec)
        if not oiio.ImageBufAlgo.copy(float_buf, buf):
            raise RuntimeError(f"OIIO copy to float failed: {oiio.geterror()}")
        src_buf = float_buf

    dst_buf = oiio.ImageBuf(oiio.ImageSpec(width, height, spec.nchannels, oiio.FLOAT))
    if not oiio.ImageBufAlgo.resize(dst_buf, src_buf, filtername=filter_name):
        raise RuntimeError(f"OIIO resize failed: {oiio.geterror()}")

    return dst_buf