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Core dumped with FFMPEG format

See original GitHub issue

When getting a reader for a video file like

video_reader = imageio.get_reader(uri='video.avi', format='FFMPEG')

the interpreter hangs indefinitely most of the times (using Python 3.4). With Python 3.5 it gives the following message:

Fatal Python error: could not acquire lock for <_io.BufferedReader name=8> at interpreter shutdown, possibly due to daemon threads

Thread 0x00007fb306522700 (most recent call first):
  File "/home/hugo/.virtualenvs/tracer/lib/python3.5/site-packages/imageio/plugins/ffmpeg.py", line 832 in run
  File "/usr/lib/python3.5/threading.py", line 914 in _bootstrap_inner
  File "/usr/lib/python3.5/threading.py", line 882 in _bootstrap

Current thread 0x00007fb317c5c740 (most recent call first):
  File "/home/hugo/.virtualenvs/tracer/lib/python3.5/site-packages/imageio/plugins/ffmpeg.py", line 402 in _terminate
  File "/home/hugo/.virtualenvs/tracer/lib/python3.5/site-packages/imageio/plugins/ffmpeg.py", line 298 in _close
  File "/home/hugo/.virtualenvs/tracer/lib/python3.5/site-packages/imageio/core/format.py", line 245 in close
  File "/home/hugo/.virtualenvs/tracer/lib/python3.5/site-packages/imageio/core/format.py", line 234 in __del__
Aborted (core dumped)

If I video_reader.close() or del video_reader manually, this problem goes away. Is this the expected behavior? Is it documented somewhere and I missed it?

Issue Analytics

State:
Created 7 years ago
Comments:9 (6 by maintainers)

Top GitHub Comments

1reaction

cachitascommented, Dec 7, 2016

Looks like it is fixed. Nice work! 👍

1reaction

cachitascommented, Nov 4, 2016

It hangs at shutdown.

Further testing shows that:

only calling r = imageio.get_reader() does not hang
calling r = imageio.get_reader() followed by r.get_meta_data() does not hang
calling r = imageio.get_reader() followed by r.get_data(some_index) hangs if the script does not reach a call to r.close()