Exception('None Image') while using custom audio source

[frankygg]

Thank you author for your great work.
I have encountered problems while using custom audio source.
I have used cropped image from the audio source and set the mouth source path to the cropped image file.
For example, when I generated the demo.csv, I saw the moth source contains 208 frame. But when I run !bash experiments/demo_vox.sh, the image path will indicate a number beyond 208 and cause Exception('None Image').
However, there was no problem while using the audio sources you provided.
Do you have any idea about this problem?
Many thanks!

[frankygg]

While running !bash experiments/demo_vox.sh, I found information like this:
dataset [VOXTestDataset] of size 172 was created
However, the Mouth_source frames created from my audio with prepare_testing_files.py are below this number (here is 172). Maybe it is the reason why Exception('None Image') occurred.
May I know how to fix this?
Many thanks!