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• arm64 : add cycle counter support

  3 décembre 2015, par Janne Grunau

  arm64 : add cycle counter support
  The ISB (instruction synchronization barrier) might be too heavy for
  
  START/STOPTIMER use but should be more accurate in checkasm where the
  
  timing overhead is subtracted.
  

  • [DBH] libavutil/aarch64/timer.h
  • [DBH] libavutil/timer.h

• FFMPEG - Windows Batch - Loudnorm Print to File

  22 août 2023, par Atlantis0813

  I would like to have the first three minutes of some M3u8 urls from a text file checked for loudness and have the results written to a file.

  


  The following Windows batch code works in the Windows terminal. But the log.txt remains empty.

  


  for /F "tokens=*" %%A in (input.txt) do ffmpeg -i %%A -ss 0 -t 180 -af loudnorm=I=-16:TP=-1.5:LRA=15:print_format=summary -f null - >> log.txt

  


  Expect Output appended to file.

  


• How to copy CUdeviceptr planes from FFmpeg AVFrame into my own CUDA memory ?

  25 avril 2024, par SexyBoooom

  I'm trying to copy a frame planes decoded by FFmpeg(CUDA) into my own CUDA memory, but i tried a lot of times and all failed.

  


  1, from FFmpeg doc, it says :

  


  /// <summary>HW acceleration through CUDA. data[i] contain CUdeviceptr pointers exactly as for system memory frames.</summary>&#xA;@AV_PIX_FMT_CUDA = 117&#xA;

  


  that means AVFrame.data[n] are the CUdeviceptr to copy from.

  


  2, i have created my own CUDA memory without problem :

  


  var dstPtr = new CUdeviceptr();
var error = cuMemAlloc_v2(ref dstPtr, length);


  


  3, try to copy from AVFrame into dstPtr, but failed :

  


  var dstPtr = new CUdeviceptr();
var error = cuMemAlloc_v2(ref dstPtr, length);  // allocate a CUDA mem for test

var plane = ffmpeg.av_frame_get_plane_buffer(avFrame, 0);  // get the plane 0 info
var srcPtr = new CUdeviceptr((long)plane->data);  // get CUdeviceptr from data[0]

error = cuMemcpyDtoD_v2(dstPtr, srcPtr, plane->size);  // try to copy from avFrame into my own CUDA mem block
Debug.Assert(error == CUResult.Success);  //  alway fail.....


  


  the copy result is alwasy ErrorInvalidValue indicates that the CUdeviceptr returned from AVFrame.data[0] is invalid or something....

  


  

  


  I really have no idea what am i doing wrong....
BTW, I have created a CUDA context for memory allocating, that said, i will set my own CUDA context as current before allocating memory, does this operation break the FFmpeg's current context ? so the copy will fail ?

  


  but anyway, no matter i use cuCtxPushCurrent_v2 or cuCtxSetCurrent, both not work.
this is just a really simple copy test, no ? but why.... :(