Crash/hang encoding movie

[lmillervedam@…]

The following bug report has been submitted:
Platform:        Linux-3.10.0-1062.1.2.el7.x86_64-x86_64-with-centos-7.7.1908-Core
ChimeraX Version: 0.91 (2019-12-23)
Description
I am having trouble encoding movies in ChimeraX. I have tried both using the spin movie button & using the command line to record a movie. Movie record appears to work (spinning is seen). Then in the bottom of the ChimeraX window it says "__ frames are encoding". At this point the program hangs, or crashes without outputting anything. There is no error displayed in the log.

Log:
UCSF ChimeraX version: 0.91 (2019-12-23)  
© 2016-2019 Regents of the University of California. All rights reserved.  
How to cite UCSF ChimeraX  

> open 05FEB2020_mutants4.cxs

opened ChimeraX session  

> help help:contact.html




OpenGL version: 3.3.0 NVIDIA 430.50
OpenGL renderer: GeForce GTX 1650/PCIe/SSE2
OpenGL vendor: NVIDIA Corporation

[Tom Goddard]

I have seen movie encoding hang in ChimeraX on a Mac when I have started ChimeraX from a shell backgrounded. When the movie encode starts, if I return to that shell it says ChimeraX is stopped. I think the ffmpeg encoder is trying to use stdin/stdout/stderr and it ends up stopping the ChimeraX process. To test if this is your problem try running ChimeraX from the shell without backgrounding it.

If this is your problem, I'll take a look at what ffmpeg is doing and see if I can fix this behavior.

[lmillervedam@…]

Hi Tom,

I tried this with ChimeraX in the foreground using the generic spin movie
and now it writes out a file. Thank you!

Best,
Lakshmi

On Thu, Feb 13, 2020 at 12:45 PM ChimeraX <ChimeraX-bugs-admin@cgl.ucsf.edu>
wrote:

[Tom Goddard]

Thanks.  I'll try to fix this behavior so movies encode in the background.

[Tom Goddard]

Fixed.

Movie encoding was running ffmpeg which apparently looks for input on stdin which stops the process if ChimeraX was run in the background. So I changed the ffmpeg invocation using Popen to specify stdin as DEVNULL.