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• Packet Corruption : Why sometimes ffmpeg .bat batch video editing makes my computer unstable unable to restart ?

  13 juin 2022, par principal-ideal-domain

  I'm doing very time consuming ffmpeg video editing. That's why I put my commands into a .bat batch file and run them over night. Usually that works fine, but from time to time when I look the next moring I see an error message of this kind :

  


  

  


  From that state on, I didn't find any good way to close the console. When I press the [x] button in the top right corner, it freezes. When I try to kill the application using the task manager nothing happens. Even explorer.exe cannot be closed using the task manager. A shutdown won't do anything. During the last month I had this problem about three times and the only way I could close it was to long press the power button of the computer until it was turned off "the bad way".

  


  Any ideas what to in such situations ?
  
Or even better : How to prevent those situations ?
What can the reason(s) be for the error ?
Do you understand the message ?

  


  When the computer is started again the next morining and I run the same .bat file again everything works fine. So the same error does not repeat and the video is edited nicely !

  


  Edit : Now, about one week after posting this question the problem occurred many more times ! It is very annoying. I guess it has to do with the external hard drive connected by USB. Sometimes it randomly interrupts the connection ! That might be the reason for the behavior. Whatever its causing the error, I want to learn a solution how to deal with this in future. I don't want to always push the reset button of my computer. I want a proper way to be able to shut it down.

  


• is this ffmpeg command optimized ?

  22 juin 2017, par Bob Ramsey

  I have a requirement to take a video, add some plain text, and then add some rotated text at different times, locations, and durations. I want to use processor power in the most efficient way this will run 20,000 times (yes, really, we’re personalizing a video for students at a U.)This is what I finally came up with :

  ffmpeg -y -i INPUT.mp4 -filter_complex 
  
    "drawtext=enable='between(t,14,16)':fontfile=tahoma.ttf:fontsize=54:fontcolor=green:x=10:y=text_h + 10:text='Dana Scully',
  
     drawtext=enable='between(t,19,23)':fontfile=tahoma.ttf:fontsize=16:fontcolor=red:x=150:y=220:text='Dana Scully  \<dana.scully\@fbi.gov\>',
  
     drawtext=enable='between(t,99,104)':fontfile=tahoma.ttf:fontsize=28:fontcolor=green:x=480:y=text_h + 160:text='Dana Scully',
  
     drawtext=enable='between(t,14,16)':fontfile=tahoma.ttf:fontsize=16:fontcolor=yellow:x=40:y=25:text='Dana Scully  \<dana.scully\@fbi.gov\>',
  
     drawtext=enable='between(t,180,186)':fontfile=tahoma.ttf:fontsize=88:fontcolor=green:x=20:y=430:text='Dana Scully'[text];
  
     color=c=#111111:s=1280x720:d=1,format=yuv444p[colorbk];
  
     [colorbk]drawtext=fontfile=tahoma.ttf:fontsize=16:fontcolor=purple:x=(w-text_w)/2:y=(h-text_h)/2:text='by',drawtext=fontfile=tahoma.ttf:fontsize=32:fontcolor=green:x=(w-text_w)/2:y=((h-text_h)/2)+50:text='Dana Scully',rotate=(-.5):ow=1280:oh=720:c=#111111,chromakey=#111111:similarity=0.01,format=yuva444p,colorkey=#111111:0.1[rotated];
  
     [text][rotated]overlay=eval=frame:x='if(gte(t,134),(if(lte(t,137),20,NAN)), NAN)':y=100[out];[out]scale=iw*.25:-1" 
  
     -crf 20 test.mp4

  Is that about as optimized as it is going to get ? I thought ffmpeg would already handle the threads based on the computer’s processor, so no real need to mess with it. The processing will all be done on AWS VMs.

  Rotating the text is what really slows it down.

  Any ideas ?

• lavc/h264dsp : optimise R-V V weight for shorter heights

  1er septembre 2024, par Rémi Denis-Courmont

  lavc/h264dsp : optimise R-V V weight for shorter heights
  The height is a power of two of up to 16 rows. The current code was
  
  optimised for large sample counts.
  T-Head C908 :
  
  h264_weight2_8_c :                                      211.7 ( 1.00x)
  
  h264_weight2_8_rvv_i32 :                   before       184.0 ( 1.15x)
  
  h264_weight2_8_rvv_i32 :                   after         54.2 ( 3.90x)
  
  h264_weight4_8_c :                                      285.7 ( 1.00x)
  
  h264_weight4_8_rvv_i32 :                   before       341.2 ( 0.86x)
  
  h264_weight4_8_rvv_i32 :                   after         82.2 ( 3.47x)
  
  h264_weight8_8_c :                                      498.7 ( 1.00x)
  
  h264_weight8_8_rvv_i32 :                   before       683.7 ( 0.73x)
  
  h264_weight8_8_rvv_i64 :                   after        128.5 ( 3.95x)
  
  h264_weight16_8_c :                                     878.2 ( 1.00x)
  
  h264_weight16_8_rvv_i32 :                  unchanged    239.5 ( 3.67x)
  SpacemiT X60 :
  
  h264_weight2_8_c :                                      207.2 ( 1.00x)
  
  h264_weight2_8_rvv_i32 :                   before       259.6 ( 0.80x)
  
  h264_weight2_8_rvv_i32 :                   after         82.2 ( 2.52x)
  
  h264_weight4_8_c :                                      290.8 ( 1.00x)
  
  h264_weight4_8_rvv_i32 :                   before       509.6 ( 0.57x)
  
  h264_weight4_8_rvv_i32 :                   after         61.5 ( 4.73x)
  
  h264_weight8_8_c :                                      498.8 ( 1.00x)
  
  h264_weight8_8_rvv_i32 :                   before      1019.8 ( 0.49x)
  
  h264_weight8_8_rvv_i64 :                   after         71.8 ( 6.95x)
  
  h264_weight16_8_c :                                     874.0 ( 1.00x)
  
  h264_weight16_8_rvv_i32 :                  unchanged    249.0 ( 3.51x)
  

  • [DH] libavcodec/riscv/h264dsp_init.c
  • [DH] libavcodec/riscv/h264dsp_rvv.S