vis.py: use basename of image when saving raw annotations to prevent file-not-found error

[walkerlala]

when setting --also_save_raw_predictions=True, a file-not-found error is report because we are saving into the --vis_logdir using the fullpath of that image.

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[walkerlala]

I signed it!

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CLAs look good, thanks!

[YknZhu]

Thanks! A more proper fix would be using the absolute path in dataset generation process?

[walkerlala]

@YknZhu The problem is we are saving into the --vis_logdir using the fullpath of that image. For example if --vis_logdir is /home/someuser/vislog and the path of image is /home/someuser/evaldata/image1.jpg, and then when --also_save_raw_predictions=True, we are saving the result into /home/someuser/vislog/home/someuser/evaldata/image1.jpg, which will raise a file-not-found error.

[YknZhu]

I see. Good catch!