warn and set projected to False if flip_y_axis is set to True, closes #440

[bw4sz]

This is a small PR to add a warning and set projected=True in deepforest.utilities.boxes_to_shapefile when setting flip_y_axis=True.

[henrykironde]

The tests are not clear to me, I may be missing something, I will give them another review later.

[henrykironde]

I think I am missing something. Shouldn't this be if not ( either projected or Flip_y_axis)

[bw4sz]

No I think thats right.

    if projected and flip_y_axis:
        with pytest.warns(UserWarning):
            gdf = utilities.boxes_to_shapefile(
                df,
                root_dir=os.path.dirname(img),
                projected=projected,
                flip_y_axis=flip_y_axis)

If the user sets projected to be True and flip_y_axis is True, it should raise a warning. Projected says the boxes are in geographic projection, there is no situation in which you would want to reflect over the y axis and get negative coordinates. The flip_y_axis is only useful in unprojected data and for programs like QGIS that have the origin flipped compared to numpy.

[henrykironde]

@bw4sz Make these changes and this will be done.

[henrykironde]

Change this comment to

# raise a warning if user sets projected to be True and flip_y_axis is True

and remove the () on the if statement

if flip_y_axis and projected:

[henrykironde]

The if statement is not needed

# Test unprojected data, including warning if flip_y_axis is set to True, but projected is False
@pytest.mark.parametrize("flip_y_axis", [True, False])
@pytest.mark.parametrize("projected", [True, False])
def test_boxes_to_shapefile_unprojected(m, flip_y_axis, projected):
    img = get_data("OSBS_029.png")
    r = rio.open(img)
    df = m.predict_image(path=img)

    with pytest.warns(UserWarning):
        gdf = utilities.boxes_to_shapefile(
            df,
            root_dir=os.path.dirname(img),
            projected=projected,
            flip_y_axis=flip_y_axis)

    # Confirm that each boxes within image bounds
    geom = geometry.box(*r.bounds)
    assert all(gdf.geometry.apply(lambda x: geom.intersects(geom)).values)