Hi Konrad,

Sorry for the delay in response, it’s been a hectic couple of weeks.

I wonder if the problem is caused by the fact that there are multiple collected_data.h5 files? E.g. in my project’s config.yaml file, I have

```
# Annotation data set configuration (and individual video cropping parameters)
video_sets:
/media/marcus/Data1/Videos/Bard/ncam-2020-12-15-11-59/FaceA.avi:
crop: 0, 1920, 0, 1080
/media/marcus/Data1/Videos/Bard/ncam-2020-12-15-11-59/SceneA.avi:
crop: 0, 1920, 0, 1080
/media/marcus/Data1/Videos/Bard/ncam-2020-12-15-11-59/SceneB.avi:
crop: 0, 1920, 0, 1080
/media/marcus/Data1/Videos/Bard/ncam-2020-12-15-11-59/SceneC.avi:
crop: 0, 1920, 0, 1080
```

I can dig into one of these files and find that the 1st entry has no values, but the 3rd does:

```
In [25]: file = "/home/marcus/DLC/BardTest/BardTest-Marcus-2021-01-24/labeled-data/FaceA/CollectedData_Marcus.h5"
In [26]: h5 = h5py.File(file, 'r')
In [27]: list(h5.keys)
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
<ipython-input-27-5ab44f6e42bd> in <module>
----> 1 list(h5.keys)
TypeError: 'method' object is not iterable
In [28]: list(h5.keys())
Out[28]: ['df_with_missing']
In [29]: grp = h5['df_with_missing']
In [30]: grp.keys()
Out[30]: <KeysViewHDF5 ['_i_table', 'table']>
In [31]: grp['table'][0]
Out[31]: (b'labeled-data/FaceA/img000761.png', [nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan])
In [32]: grp['table'][2]
Out[32]: (b'labeled-data/FaceA/img001407.png', [ 481.77758007, 278.85548864, nan, nan, 467.06090884, 435.83331508, 611.7748426 , 426.02220093, nan, nan, 511.21092253, 477.53055023, 687.81097728, 109.6137695 , nan, nan, 766.2998905 , 249.42214618, nan, nan, 913.46660279, 364.70273748, nan, nan, 1038.55830824, 676.20561183, nan, nan, 572.53038598, 1002.4251574 , 619.13317821, 673.75283329, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan])
```

But when I run dropimagesduetolackofannotation I get the results described above, with all images staying in place.

Any idea what I’ve done?