Demux generator does not see new data written to BytesIO buffer

[robsmith11]

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Overview

It seems that only the data that's already in a BytesIO buffer when it's passed to av.open is able to be used by the demux generator. When I write new bytes (from a live websocket fees) to the buffer, the demux generator doesn't see them.

Expected behavior

New non-zero size packets are generated.

Actual behavior

The generated packets all have size zero.

Traceback:

None

Investigation

Googled

Reproduction

...

Versions

• OS: linux
• PyAV runtime:

Latest from pip

• PyAV build:

... 

• FFmpeg:

.. . 

Research

I have done the following:

Googled

Additional context

None