Update feature_extraction_utils.py
Author: daquarti
Pull request: yes

config.json is needed to use custom ViTForImageClassification.from_pretrained()
but FEATURE_EXTRACTOR_NAME = "preprocessor_config.json"
so ---> output_feature_extractor_file = os.path.join(save_directory, "config.json") 

preprocessor_config.json

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Comments:
@patrickvonplaten could you take a look at this?

Hey @daquarti, 

This looks wrong to me -> the feature extractors don't save their parameters into `config.json`, but into `preprocessor_config.json`. Could you elaborate a bit more on the PR?

Thanks for help @patrickvonplaten , maybe may solution was not good because ViTFeatureExtractor.from_pretrained() needs "preprocessor_config.json"

The problem is the following:
When I use ViTFeatureExtractor.from_pretrained() "preprocessor_config.json" woks good.
but them, when I use ViTForImageClassification.from_pretrained() "config.json" is needed. If I rename "preprocessor_config.json" like "config.json"  ViTForImageClassification.from_pretrained() works


This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the [contributing guidelines](https://github.com/huggingface/transformers/blob/master/CONTRIBUTING.md) are likely to be ignored.

Note that in order to load the model `ViTForImageClassification` one needs a `config.json`. In order to load the feature extractor one needs `preprocessor_config.json`.

Those are actually two different configs for two different classes

This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the [contributing guidelines](https://github.com/huggingface/transformers/blob/master/CONTRIBUTING.md) are likely to be ignored.