Function make_attn

sat/sgm/modules/diffusionmodules/model.py:233–260

(in_channels, attn_type="vanilla", attn_kwargs=None)

def make_attn(in_channels, attn_type="vanilla", attn_kwargs=None):
    assert attn_type in [
        "vanilla",
        "vanilla-xformers",
        "memory-efficient-cross-attn",
        "linear",
        "none",
    ], f"attn_type {attn_type} unknown"
    if version.parse(torch.__version__) < version.parse("2.0.0") and attn_type != "none":
        assert XFORMERS_IS_AVAILABLE, (
            f"We do not support vanilla attention in {torch.__version__} anymore, "
            f"as it is too expensive. Please install xformers via e.g. 'pip install xformers==0.0.16'"
        )
        attn_type = "vanilla-xformers"
    print(f"making attention of type '{attn_type}' with {in_channels} in_channels")
    if attn_type == "vanilla":
        assert attn_kwargs is None
        return AttnBlock(in_channels)
    elif attn_type == "vanilla-xformers":
        print(f"building MemoryEfficientAttnBlock with {in_channels} in_channels...")
        return MemoryEfficientAttnBlock(in_channels)
    elif type == "memory-efficient-cross-attn":
        attn_kwargs["query_dim"] = in_channels
        return MemoryEfficientCrossAttentionWrapper(**attn_kwargs)
    elif attn_type == "none":
        return nn.Identity(in_channels)
    else:
        return LinAttnBlock(in_channels)


class Model(nn.Module):