def METHOD_NAME():
    """
    Camera optimization example using pulsar.
    Writes to `cam.gif`.
    """
    LOGGER.info("Loading reference...")
    # Load reference.
    ref = (
        torch.from_numpy(
            imageio.imread(
                "../../tests/pulsar/reference/examples_TestRenderer_test_cam.png"
            )[:, ::-1, :].copy()
        ).to(torch.float32)
        / 255.0
    ).to(DEVICE)
    # Set up model.
    model = SceneModel().to(DEVICE)
    # Optimizer.
    optimizer = optim.SGD(
        [
            {"params": [model.cam_pos], "lr": 1e-4},  # 1e-3
            {"params": [model.cam_rot], "lr": 5e-6},
            {"params": [model.cam_sensor], "lr": 1e-4},
        ]
    )
    LOGGER.info("Writing video to `%s`.", path.abspath("cam.gif"))
    writer = imageio.get_writer("cam.gif", format="gif", fps=25)
    # Optimize.
    for i in range(300):
        optimizer.zero_grad()
        result = model()
        # Visualize.
        result_im = (result.cpu().detach().numpy() * 255).astype(np.uint8)
        cv2.imshow("opt", result_im[:, :, ::-1])
        writer.append_data(result_im)
        overlay_img = np.ascontiguousarray(
            ((result * 0.5 + ref * 0.5).cpu().detach().numpy() * 255).astype(np.uint8)[
                :, :, ::-1
            ]
        )
        overlay_img = cv2.putText(
            overlay_img,
            "Step %d" % (i),
            (10, 40),
            cv2.FONT_HERSHEY_SIMPLEX,
            1,
            (0, 0, 0),
            2,
            cv2.LINE_AA,
            False,
        )
        cv2.imshow("overlay", overlay_img)
        cv2.waitKey(1)
        # Update.
        loss = ((result - ref) ** 2).sum()
        LOGGER.info("loss %d: %f", i, loss.item())
        loss.backward()
        optimizer.step()
    writer.close()
    LOGGER.info("Done.")