dewarping: `gpu_id` does not default to `-1` in any case

[mweidling]

Using ocrd/all:maximum I get the following error when executing ocrd-anybaseocr-dewarp -I OCR-D-DESKEW-PAGE -O OCR-D-DEWARP-PAGE:

RuntimeError: Found no NVIDIA driver on your system. Please check that you have an NVIDIA GPU and installed a driver from http://www.nvidia.com/Download/index.aspx

On the other hand, explicitly passing -gpu_id=-1 yields

model [Pix2PixHDModel] was created

I would have expected from the docs that -gpu_id=-1 is the default and implicitly passed, while what I see implies the contrary.

[mweidling]

I just noticed that there is no further output apart from the message model [Pix2PixHDModel] was created (i.e. no dir OCR-D-DEWARP-PAGE has been created), so there seems to be another problem that doesn't throw an error.

[bertsky]

Yes, CPU fallback is broken, but so is the whole processor (see #72 and #42).

IIRC we long ago decided to abandon the whole module – except for the cropper (for which I still have an improved version in the pipeline, and wanted to factor that out into ocrd_cis later-on).

[mweidling]

Ah, okay, thanks for the explanation! I was simply confused by the docs on the website which doesn't indicate that this is broken.

[kba]

fixed by #89