there.
Using pyglet.image.ImageGrid(), is there any way to start off the grid from the top left, instead of the bottom left?
So, the only 'awfull' solution I currently have is:

To verticaly flip the image on the drive
Load the image as a texture and flip it back with get_texture()
Put it into an ImageGrid()
Reverse() the ImageGrid-sequence
Pyglet.image.ImageGrid() - indexing from top left