Add support for GIF

[emonigma]

Describe the bug

I install the package with Conda, Python 3.8 and PIP. I run it on a GIF image and get this error:

Traceback (most recent call last):
  File "/home/ubuntu/miniconda3/envs/oemer/bin/oemer", line 8, in <module>
    sys.exit(main())
  File "/home/ubuntu/miniconda3/envs/oemer/lib/python3.8/site-packages/oemer/ete.py", line 280, in main
    mxl_path = extract(args)
  File "/home/ubuntu/miniconda3/envs/oemer/lib/python3.8/site-packages/oemer/ete.py", line 131, in extract
    staff, symbols, stems_rests, notehead, clefs_keys = generate_pred(str(img_path), use_tf=args.use_tf)
  File "/home/ubuntu/miniconda3/envs/oemer/lib/python3.8/site-packages/oemer/ete.py", line 51, in generate_pred
    staff_symbols_map, _ = inference(
  File "/home/ubuntu/miniconda3/envs/oemer/lib/python3.8/site-packages/oemer/inference.py", line 60, in inference
    image = Image.fromarray(image).convert("RGB")
  File "/home/ubuntu/miniconda3/envs/oemer/lib/python3.8/site-packages/PIL/Image.py", line 3084, in fromarray
    arr = obj.__array_interface__
AttributeError: 'NoneType' object has no attribute '__array_interface__'

I get the same error using oemer[tf].

Input Image

I attach the PNG and the GIF version. Only the GIF version causes the error.

Full Traceback

2023-11-17 10:45:48 Extracting staffline and symbols
/home/ubuntu/miniconda3/envs/oemer/lib/python3.8/site-packages/onnxruntime/capi/onnxruntime_inference_collection.py:69: UserWarning: Specified provider 'CoreMLExecutionProvider' is not in available provider names.Available providers: 'TensorrtExecutionProvider, CUDAExecutionProvider, AzureExecutionProvider, CPUExecutionProvider'
  warnings.warn(
2023-11-17 10:45:50.437510351 [E:onnxruntime:Default, provider_bridge_ort.cc:1480 TryGetProviderInfo_CUDA] /onnxruntime_src/onnxruntime/core/session/provider_bridge_ort.cc:1193 onnxruntime::Provider& onnxruntime::ProviderLibrary::Get() [ONNXRuntimeError] : 1 : FAIL : Failed to load library libonnxruntime_providers_cuda.so with error: libcublasLt.so.11: cannot open shared object file: No such file or directory

2023-11-17 10:45:50.437708300 [W:onnxruntime:Default, onnxruntime_pybind_state.cc:747 CreateExecutionProviderInstance] Failed to create CUDAExecutionProvider. Please reference https://onnxruntime.ai/docs/execution-providers/CUDA-ExecutionProvider.html#requirements to ensure all dependencies are met.
Traceback (most recent call last):
  File "/home/ubuntu/miniconda3/envs/oemer/bin/oemer", line 8, in <module>
    sys.exit(main())
  File "/home/ubuntu/miniconda3/envs/oemer/lib/python3.8/site-packages/oemer/ete.py", line 280, in main
    mxl_path = extract(args)
  File "/home/ubuntu/miniconda3/envs/oemer/lib/python3.8/site-packages/oemer/ete.py", line 131, in extract
    staff, symbols, stems_rests, notehead, clefs_keys = generate_pred(str(img_path), use_tf=args.use_tf)
  File "/home/ubuntu/miniconda3/envs/oemer/lib/python3.8/site-packages/oemer/ete.py", line 51, in generate_pred
    staff_symbols_map, _ = inference(
  File "/home/ubuntu/miniconda3/envs/oemer/lib/python3.8/site-packages/oemer/inference.py", line 60, in inference
    image = Image.fromarray(image).convert("RGB")
  File "/home/ubuntu/miniconda3/envs/oemer/lib/python3.8/site-packages/PIL/Image.py", line 3084, in fromarray
    arr = obj.__array_interface__
AttributeError: 'NoneType' object has no attribute '__array_interface__'

Command You Execute

$ oemer ss015.gif 

[BreezeWhite]

For the scenario of OMR tasks, I think the support of GIF format is a little bit weird, since such tasks always expect input format like JPG or PNG, not GIF. The best way is convert the GIF image into a static image format as mentioned before.
Closing this as the stated reason above.

[emonigma]

That's fair and thanks for the quick reply. How about just improving the error message, such as GIF images not supported, convert first to PNG or JPG?

[BreezeWhite]

That's a reasonable modification. If you have time on this issue, I'll be glad to assist you on the code refactoring.