Recherche avancée

Sur d’autres sites (5154)

• arm : Fix SIGBUS on ARM when compiled with binutils 2.29

  31 août 2017, par Martin Storsjö

  arm : Fix SIGBUS on ARM when compiled with binutils 2.29
  In binutils 2.29, the behavior of the ADR instruction changed so that 1 is
  
  added to the address of a Thumb function (previously nothing was added). This
  
  allows the loaded address to be passed to a BLX instruction and the correct
  
  mode change will occur.
  See : https://sourceware.org/bugzilla/show_bug.cgi?id=21458
  By using adr with a label that isn’t annotated as a thumb function,
  
  we avoid the new behaviour in binutils 2.29 and get the same behaviour
  
  as in prior releases, and as in other assemblers (ms armasm.exe,
  
  clang’s built in assembler) - an idea that Janne Grunau came up with.
  Signed-off-by : Martin Storsjö <martin@martin.st>
  

  • [DBH] libavcodec/arm/h264idct_neon.S

• Using FFmpeg within a python application : ffmpeg tool or libav* libraries ?

  5 septembre 2017, par user2457666

  I am working on a python project that uses ffmpeg as part of its core functionality. Essentially the functionality from ffmpeg that I use boils down to these two commands :

  ffmpeg -i udp:// -qscale:v 2 -vf "fps=30" sttest%04d.jpg
  
  ffmpeg -i udp:// -map data-re -codec copy -f data out.bin

  Pretty simple stuff.

  I am trying to create a self-contained program (which uses the above ffmpeg functionality) that can easily be installed on any particular system without relying on that system having the necessary dependencies, as hopefully I would package those dependencies with the program itself.

  With that in mind, would it be best to use the libav* libraries to perform this functionality from within the program ? Or would a wrapper (ffmpy) for the ffmpeg command line tool be a better option ? My current thinking on the drawbacks of each is that using the libraries may be the best practice, but it seems overly complex to have to learn how to use them (and potentially learn C, which I’ve never learned, in the process) just to do those two basic things I mentioned above. The libraries overall are a bit of a bit of a black box to me and don’t have very much documentation. But the problem with using a wrapper for ffmpeg would be that it essentially relies on calling a subprocess, which seems somewhat sloppy. Although I’m not sure why I feel so viscerally opposed to subprocesses.

• Two USB cams to two rtsp-simple-servers simultaneously

  20 juin 2022, par Imm

  Like in title, I have 2 USB cams and I need to create two RTSP streams. I'm using FFmpeg and rtsp-simple-server and it's working with one cam with this configuration (rtsp-simple-server.yml) :

  


  paths:
  cam:
    runOnInit: ffmpeg -f dshow -video_device_number 0 -i video="UVC Camera" -c:v libx264 -preset ultrafast -tune zerolatency -b:v 600k -f rtsp rtsp://192.168.5.203:8554/cam
    runOnInitRestart: yes


  


  but I can't figure it out with second cam. I tried to make second instance of rtsp-simple-server in separete console and it doesn't work. I set it up like this (and few other ways with different port etc.) :

  


  paths:
  cam:
    runOnInit: ffmpeg -f dshow -video_device_number 1 -i video="UVC Camera" -c:v libx264 -preset ultrafast -tune zerolatency -b:v 600k -f rtsp rtsp://192.168.5.203:8555/cam2
    runOnInitRestart: yes


  


  I get this error as result : Only one use of each socket address (protocol / network address / port) is allowed. and I still think there is better way to solve this with proper configuration.

  


  I hoping for your help !