[FFmpeg-trac] #8550(avformat:new): Cannot open DShow capture device twice with same settings

[FFmpeg]

#8550: Cannot open DShow capture device twice with same settings
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             Reporter:  uzyfeo       |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:  avformat     |                  Version:
             Keywords:               |  unspecified
  dshow,win32,mfc                    |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
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 Summary of the bug:
   When trying to call avformat_open_input function with specific framerate
 and resolution set for video capture device, it opens without errors.
 After closing it (cleaning everything up properly) and openning it again
 with those same settings, device cannot be opened (this particular
 function returns -5).
   We are using ffmpeg libs in few of our MFC applications. This issue
 started happening recently (about a week back), without a warning or clear
 cause (same code that worked doesn't seem to cut it anymore). It seems to
 be a Windows problem (maybe caused by some update) rather then error of
 the lib itself, but we cannot confirm this.
   We used 4.2.1 for a while and recently updated to 4.2.2 version.
 Thinking it has to do something with newer version, we tried to roll it
 back to 4.2.1 without success. Note that on this version, it worked before
 without issues (hence why we think this might not be issue of the lib). We
 then tried out latest snapshot with same results.

 How to reproduce:
   Open video capture device with specific supported framerate and
 resolution with avformat_open_input function. Then, close it and free all
 ffmpeg resources (to simulate our usage). After this, try to reinitialize
 everything again the same way and try to open device with those same
 settings again. Call should fail with return value -5.

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Ticket URL: <https://trac.ffmpeg.org/ticket/8550>
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