Recherche avancée

Sur d’autres sites (6756)

• lowpass filter Q factor online simulator (bode plot)

  5 novembre 2016, par user1320370

  I like to add a low pass filter on a audio file myfile.flac with ffmpeg.

  The parameters to choose are the frequency and Q-factor or slope.

  ffmpeg -i myfile.flac -af "highpass=f=9000:width_type=q:width=0.707" output.flac

  The default q-factor is 0.707.

  I like to increase the q-factor but a too high value can cause excessive resonance.

  For this reason before do it can be useful to test with a bode plot simular (online if exist) that can accept filter type (lowpass, highpass) , frequency and Q-factor.

  Someone can please send a link of a bode plot that show a simulator like this ?

  thank you !!

• mplayer generating online three thumbnail of video

  5 mai 2013, par soac

  I am trying to create thumbnail of video using mplayer but it is only creating 3 thumbnail of video and then repeating the last thumbnail again and again.

  MPlayer command 1 :

  mplayer video/1.mp4 -sstep 5 -endpos 25 -nosound -vf scale=96:64 -vo jpeg:quality=80:outdir=$tmpPath 2>log.txt

  Problem : It create 3 different image and then repeat last image again and again.

  MPlayer command 2 :

  mplayer video/1.mp4 -sstep 5 -endpos 25 -nosound -frames 5 -vf scale=96:64 -vo jpeg:quality=80:outdir=$tmpPath 2>log.txt

  Problem : It create 3 different image and then repeat last image 2 times, If I change -frames to 10 than it repeat last image 7 times.

  MPlayer command 3 :

  mplayer video/1.mp4 -ss 5 -nosound -frames 1 -vf scale=96:64 -vo jpeg:quality=80:outdir=$tmpPath /
  video/1.mp4 -ss 10 -nosound -frames 1 -vf scale=96:64 -vo jpeg:quality=80:outdir=$tmpPath /
  video/1.mp4 -ss 15 -nosound -frames 1 -vf scale=96:64 -vo jpeg:quality=80:outdir=$tmpPath /
  video/1.mp4 -ss 20 -nosound -frames 1 -vf scale=96:64 -vo jpeg:quality=80:outdir=$tmpPath /
  video/1.mp4 -ss 15 -nosound -frames 1 -vf scale=96:64 -vo jpeg:quality=80:outdir=$tmpPath /
  2>log.txt
  

  Problem : Same problem as above described. 3 thumbnail difference and other are same. Duration of video is 27 seconds. I run this command on mplayer and mplayer2 but same result. MPlayer Binary are taken from http://sourceforge.net/projects/smplayer/files/

  I want MPlayer to capture thumbnail after every X seconds using MPlayer not FFMPEG. I am already using FFMPEG for creating thumbnail and it is working fine. My Operating System is Windows 7. Log File

  MPlayer Redxii-SVN-r36237-4.6.3 (C) 2000-2013 MPlayer Team Custom build by
  Redxii, http://smplayer.sourceforge.net Compiled against FFmpeg version
  N-52748-g1ef82cc Build date : Sun May 5 03:45:49 EDT 2013 getch2 : 6 can't get
  number of input events [disabling console input] Playing
  D :/wamp/www/videoconverter/content/original/3.mp4. libavformat version 55.4.101
  (internal) libavformat file format detected. [lavf] stream 0 : video (h264), -vid
  0 [lavf] stream 1 : audio (aac), -aid 0, -alang und VIDEO : [H264] 960x540 24bpp
  25.000 fps 2087.1 kbps (254.8 kbyte/s) Clip info : major_brand : isom
  minor_version : 512 compatible_brands : isomiso2avc1mp41 creation_time : 1970-01-01
  00:00:00 encoder : Lavf52.77.0 comment : www.freemake.com Load subtitles in
  D :/wamp/www/videoconverter/content/original/ jpeg : Progressive JPEG disabled.
  jpeg : Baseline JPEG enabled. Opening video filter : [scale w=96 h=64]
  ==========================================================================
  Opening video decoder : [ffmpeg] FFmpeg's libavcodec codec family libavcodec
  version 55.7.100 (internal) Selected video codec : [ffh264] vfm : ffmpeg (FFmpeg
  H.264)
  ==========================================================================
  Audio : no sound Starting playback... Movie-Aspect is 1.78:1 - prescaling to
  correct movie aspect. [swscaler @ 01400520]BICUBIC scaler, from yuv420p to rgb24
  using MMXEXT VO : [jpeg] 96x64 => 113x64 RGB 24-bit jpeg :
  content/tmp/sprites/HxHtQGKbsV - Output directory already exists and is
  writable. Movie-Aspect is 1.78:1 - prescaling to correct movie aspect. VO :
  [jpeg] 96x64 => 113x64 RGB 24-bit jpeg : content/tmp/sprites/HxHtQGKbsV - Output
  directory already exists and is writable. V : 0.0 0/ 0 ??% ??% ??, ?% 0 0 V : 5.8
  0/ 0 ??% ??% ??, ?% 0 0 V : 10.6 0/ 0 ??% ??% ??, ?% 0 0 V : 18.5 0/ 0 ??% ??% ??, ?%
  0 0 V : 25.6 0/ 0 ??% ??% ??, ?% 0 0 V : 35.8 0/ 0 ??% ??% ??, ?% 0 0 V : 35.8 0/ 0
   ??% ??% ??, ?% 0 0 V : 35.8 0/ 0 ??% ??% ??, ?% 0 0 V : 35.8 0/ 0 ??% ??% ??, ?% 0 0
  V : 35.8 0/ 0 ??% ??% ??, ?% 0 0 V : 35.8 0/ 0 ??% ??% ??, ?% 0 0 V : 35.8 0/ 0 ??%
   ??% ??, ?% 0 0 Exiting... (End of file)
  

• Online timelapse creation with ffmpeg

  27 mai 2016, par Michael

  I would like to create a timelapse using a command line tool like ffmpeg. The usual way is to prepare a series of images first. In my case it is not possible, because discrete images would take too much space, and there is nearly no difference between subsequent images so they compress extremely well as a video.

  So I’m looking for a way to create a video file, keep it opened and then just append successive images to it without intermediate files.