I've been trying to use:
https://github.com/gpac/gpac/wiki/thumbs

So my command was:
```gpac -i "input.mp4" reframer:saps=1 thumbs:snap=30:grid=6x30 -o dump/$num$.png```

But I get:

```
No filter chain found for PID V1 in filter reframer to any loaded filters - NOT CONNECTED
No filter chain found for PID A2 in filter reframer to any loaded filters - NOT CONNECTED
Filters not connected:
 "thumbs" (js=/usr/local/share/gpac/scripts/jsf/thumbs/init.js:snap=30:grid=6x30) (idx=3)
fout (dst=dump/$.png) (idx=4)
```

How to dump thumbs?
This is a GitHub Issue
repo:gpac
owner:gpac
Title : How to dump thumbs?
Issue date:

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I've been trying to use:
https://github.com/gpac/gpac/wiki/thumbs

So my command was:
```gpac -i "input.mp4" reframer:saps=1 thumbs:snap=30:grid=6x30 -o dump/$num$.png```

But I get:

```
No filter chain found for PID V1 in filter reframer to any loaded filters - NOT CONNECTED
No filter chain found for PID A2 in filter reframer to any loaded filters - NOT CONNECTED
Filters not connected:
 "thumbs" (js=/usr/local/share/gpac/scripts/jsf/thumbs/init.js:snap=30:grid=6x30) (idx=3)
fout (dst=dump/$.png) (idx=4)
```

--- end body ---
