Recherche avancée

Sur d’autres sites (9963)

• Speed of the x265 and ffmpeg HEVC based encoding

  10 mai 2015, par userDtrm

  I’m trying to perform a real-time encoding of a video using HEVC with ffmpeg. I’m able to achieve the required performance when running the x265 encoder separately without the support of ffmpeg. This way the my system can perform the encoding at 30 frames per second. However, my requirement is to create a MPEG-TS stream with the encoded content and therefore, the video is encoded with the ffmpeg as follows :

  ffmpeg -s:v 1280x720 -i input.yuv -c:v libx265 -x265-params crf=20:keyint=25:fps=25:preset=ultrafast -f mpegts out.ts

  Strangely, the performance of the encoding is reduced drastically and I’m only able to achieve an encoding performance of just 10 frames per second.

  Is this a problem of the multiplexing process within ffmpeg ?. Could someone please help me to resolve this issue.

  Thanks.

• Code forks fine on macbook laptop..but on Imac(Yosemite) I get errors in my shell script

  2 mars 2015, par arantx

  I’m still figuring out how to work within the terminal, mainly with FFmpeg at the moment. I have this code running for a while now on my macbook pro (snow leopard I think). It works fine, no glitches whatsover. I just got an Imac (yosemite) and I wanted to install the same code, but now it gives these minor stupid syntax errors - that are not at fault on my laptop ! Its seems bizar to me, but maybe it’s something I forgot to install .. like a certain library ? I’ve tried to use the same steps as before but ofcourse I might have forgotten about one..

  The code will make a clip of 5 seconds on every hour via the embedded webcam, (the hourly notice is being programmed within crontab). This is the shell script :

  ---

  #!/bin/bash
  
  
  
  FNAME=videocapture_`date +"%F_%H_%M"`.mpg
  
  echo $FNAME
  
  
  
  /usr/local/bin/ffmpeg -t 5 -f avfoundation -i "default" $FNAME

  ---

  And these are the erros (I tried to change a few small syntaxes to see if it would stop but it just finds new errors)

  "SyntaxError: EOL while scanning string literal
  
  Arantxas-iMac:~ arantx$ python /Users/arantx/Documents/terminal\ stuff/camera.sh 
  
    File "/Users/arantx/Documents/terminal stuff/camera.sh", line 3
  
      FNAME=videocapture_'date +"%F_%H_%M"`.mpeg
  
                                               ^
  
  SyntaxError: EOL while scanning string literal
  
  Arantxas-iMac:~ arantx$ python /Users/arantx/Documents/terminal\ stuff/camera.sh 
  
    File "/Users/arantx/Documents/terminal stuff/camera.sh", line 3
  
      FNAME=videocapture_'date +"%F_%H_%M"`.mpeg 
  
                                                ^
  
  SyntaxError: EOL while scanning string literal
  
  Arantxas-iMac:~ arantx$ python /Users/arantx/Documents/terminal\ stuff/camera.sh 
  
    File "/Users/arantx/Documents/terminal stuff/camera.sh", line 3
  
      FNAME=videocapture_'date +"%F_%H_%M"`.mp4"

  ---

  If someone can point something out that I might have missed, let me know !

  Kind regards,

  Arantxa

• Revision 90ea10ec91 : Merge "Remove unnecessary speed feature checking"

  12 mars 2015, par Jingning Han

  Merge "Remove unnecessary speed feature checking"