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• FFMPEG - colorkey [closed]

  17 mai, par Acnologla

  i am using the following command to remove chroma key:

  ffmpeg -i black.png -i video.mp4 -filter_complex '[1:v]colorkey=0x70d021:0.35:0.15[ckout];[0:v][ckout]overlay[out]' -map '[out]' video-.mp4

  but it results in these strange things around her

  original video

  Out video

• What are all of the file extensions supported by FFmpeg

  17 mai, par zjevander

  How would I go about getting a list of all the file extensions supported by FFmpeg for use in an ExtensionFilter used by FileChooser in JavaFX?

  I am familiar with the "-codecs" and "-formats" options from FFmpeg, but these list the format and codec names which do not necessarily coincide with their file extensions.

  e.g. (partial output from "ffmpeg -formats")

  • D aac raw ADTS AAC (Advanced Audio Coding)
  • DE ac3 raw AC-3
  • E matroska Matroska

  parsing aac and ac3 from the output of ffmpeg would work fine to create file extensions for those types of files, but matroska has ".mkv" file extension.

• Convert a bash script to Windows bat script [closed]

  17 mai, par gyandoo

  I have a bash script, now I need to convert it to bat.

  What the script does is based on the shortcut the script checks the audio codec and video codec using ffprobe and then loops through all the files in the folder to convert the file(s) using the presets based on which one the shortcut calls.

  It also limits the processor usage before running ffmpeg.

  Here's the script:

  #!/bin/sh
  FILES="/home/red/Downloads/to_convert/*"
  to_convert="/home/red/Downloads/to_convert"
  TYPE="$1"
  #echo "$TYPE"
  if [ -e '/tmp/convert.txt' ]; then
    echo "Ffmpeg is currently converting a file!"
    exit 0
  else
  if [ "$(ls -A $to_convert)" ];
  then
      #Create a temp file so if the script is run hourly and there is an existing instance running the scripts exits
      echo >> '/tmp/convert.txt'
      #iterate through each file in the directory
      for f in $FILES
      do
      FILENAME1=$(basename "$f")
      FILENAME=${FILENAME1%.*}
  
      
      ##  Detect what audio codec is being used:
      audio=$(ffprobe "$f" 2>&1 | sed -n '/Audio:/s/.*: \([a-zA-Z0-9]*\).*/\1/p' | sed 1q)
      ##  Detect video codec:
      video=$(ffprobe "$f" 2>&1 | sed -n '/Video:/s/.*: \([a-zA-Z0-9]*\).*/\1/p' | sed 1q)
      ##  Set default audio settings (you may need to use a different encoder,
      ##  since libfdk_aac is not re-distributable)
      aopts="-c:a libfdk_aac -vbr 3"
      ##  Set default video settings:
      vopts="-c:v libx264 -crf 22 -preset veryfast"
  
      case "$audio" in
          aac|mp3 )
      #If the audio is one of the MP4-supported codecs,
      #copy the stream instead of transcoding
              aopts="-c:a copy"
              ;;
          "" )
      #If there is no audio stream, don't bother with audio
              aopts="-an"
              ;;
          * )
              ;;
      esac
  
      case "$video" in
      #If the video stream is one of the MP4-compatible formats,
      #copy the stream
          h264|mpeg4|mpeg2video|mpeg1video )
              vopts="-c:v copy"
              ;;
          "" )
      #If no video stream is detected, don't bother with video
              vopts="-vn"
              ;;
          * )
              ;;
      esac
  
      
      if [ "$TYPE" = "shrink" ]; then
      
        taskset -c 0,2 ffmpeg -i "$f" -vcodec libx265 -crf 28 -map_metadata -1 "/home/red/Downloads/done/""$FILENAME"".mp4" && success=0 || success=1
  
      elif [ "$TYPE" = "phone" ]; then
  
        taskset -c 0,2 ffmpeg -y -i "$f" -vf scale=640:-2 -map_metadata -1 "/home/red/Downloads/done/""$FILENAME"".mp4" && success=0 || success=1
  
      elif [ "$TYPE" = "pmv" ]; then
  
        taskset -c 0,2 ffmpeg -y -i "$f" -vf scale=360:-2 -map_metadata -1 "/home/red/Downloads/done/""$FILENAME"".mp4" && success=0 || success=1      
  
      elif [ "$TYPE" = "music" ]; then
  
        taskset -c 0,2 ffmpeg -i "$f" -acodec libmp3lame "/home/red/Downloads/done/""$FILENAME"".mp3" && success=0 || success=1  
  
      elif [ "$TYPE" = "audio-boost" ]; then
  
        taskset -c 0,2 ffmpeg -i "$f" -vcodec copy -af "volume=10dB" "/home/red/Downloads/done/""$FILENAME"".mp4" && success=0 || success=1
  
      elif [ "$TYPE" = "burn-first-sub" ]; then  
  
        taskset -c 0,2 ffmpeg -i "$f" -vf "subtitles=""$f"":si=0'" "/home/red/Downloads/done/""$FILENAME"".mp4" && success=0 || success=1
  
      elif [ "$TYPE" = "burn-srt" ]; then  
  
        taskset -c 0,2 ffmpeg -i "$f" -vf "subtitles=/home/red/Downloads/to_convert/""$FILENAME"".srt" "/home/huckleberry/Downloads/done/""$FILENAME"".mp4" && success=0 || success=1
  
      elif [ "$TYPE" = "audio-track2" ]; then  
  
        taskset -c 0,2 ffmpeg -y -i "$f" -map 0:v -map 0:a:1 $vopts $aopts -map_metadata -1 "/home/red/Downloads/done/""$FILENAME"".mp4" && success=0 || success=1
  
      elif [ "$TYPE" = "split" ]; then  
  
        taskset -c 0,2 MP4Box -splits 1996800 "$f" && success=0 || success=1
  
      elif [ "$TYPE" = "fix" ]; then  
        taskset -c 0,2 ffmpeg -y -i "$f" -map 0:v:0 -map 0:a:0 -vcodec libx264 -acodec aac -map_metadata -1 "/home/red/Downloads/done/""$FILENAME"".mp4" && success=0 || success=1
  
      else    
  
        taskset -c 0,2 ffmpeg -y -i "$f" -map 0:v -map 0:a:0 $vopts $aopts -map_metadata -1 "/home/red/Downloads/done/""$FILENAME"".mp4" && success=0 || success=1
  
        TYPE="converted"
  
      fi
  
      
      if [ $success -eq 0 ]; then
          swaks --header Subject:"${TYPE} - ${FILENAME}" --body "${FILENAME}" -S
          echo "Removing $f file..."
          rm "$f"
      else
          swaks --header Subject:"failed - ${FILENAME}" --body "${FILENAME}" -S
          echo "process failed"
      fi    
     
      done
      
      #remove the temp file created
      rm "/tmp/convert.txt"
      exit 0
  else
      echo "to_convert folder is empty"
      exit 0
  fi
  exit 0
  fi
  
  

• ffmpeg : Apply a time-based expr to control intensity of lowpass, highpass, aphaser, or aecho [closed]

  17 mai, par Wes Modes

  I am procedurally constructing complexFilters for ffmpeg via fluent-ffmpeg. My fluent-ffmpeg complex filters look like:

  {
     "filter": "volume",
     "options": {
         "volume": "min(1, max(0, ((cos(PI * t * 1 / 13) * 1 + cos(PI * t * 1 / 7) * 0.5 + cos(PI * t * 1 / 3) * 0.25) +
  -0.5 ) * 0.75 * -1 + 0.5))",
         "eval": "frame"
      },
      "inputs": "track_1_output",
      "outputs": "track_1_adjusted"
  },
  

  Note that I am using an expression to determine the volume dynamically.

  Here I'm testing on the command line, to understand the mysteries of lightly-documented ffmpeg filters. I'm fading in and out two sources, intertwined in the output. Now I want to apply lowpass, highpass, aphaser, and/or aecho to the transitions using a time-based expr.

  I've already succeeded using the volume filter to fade the sources in and out (Note that the sine has reversed polarity for the second volume filter):

  # working fade in/out
  ffmpeg -i knox.mp3 -i static.mp3 -filter_complex \
  "[0:a] \
      volume = 'min(1, max(0, 0.5 + 0.5 * cos(PI * t / 5)))': eval=frame \
      [a0]; \
  [1:a] \
      volume = 'min(1, max(0, 0.5 - 0.5 * cos(PI * t / 5)))': eval=frame \
      [a1]; \
  [a0][a1]
      amix = inputs=2: duration=shortest" \
  -c:a libmp3lame -q:a 2 output.mp3
  

  ffmpeg -filters says that lowpass has time-based support:

    T.. = Timeline support
   TSC lowpass           A->A       Apply a low-pass filter with 3dB point frequency.
  

  How can I similarly apply these other filters to source1 using a time-bassed expr? I was unsuccessful in figuring out lowpass and highpass:

  # applying a lowpass filter
  ffmpeg -i knox.mp3 -i static.mp3 -filter_complex \
  "[0:a] \
      volume = 'min(1, max(0, 0.5 + 0.5 * cos(PI * t / 5)))': eval=frame, \
      lowpass=f=3000: mix='0.5 + 0.5 * cos(PI * t / 5)' \
      [a0]; \
  [1:a] \
      volume = 'min(1, max(0, 0.5 - 0.5 * cos(PI * t / 5)))': eval=frame \
      [a1]; \
  [a0][a1]
      amix = inputs=2: duration=shortest" \
  -c:a libmp3lame -q:a 2 output.mp3
  

  With the resultant error:

  [Parsed_lowpass_1 @ 0x7f9a72005c00] [Eval @ 0x7ff7bec423d8] Undefined constant or missing '(' in 't/5)'
  [Parsed_lowpass_1 @ 0x7f9a72005c00] Unable to parse option value "0.5 + 0.5 * cos(PI * t / 5)"
  Error applying option 'mix' to filter 'lowpass': Invalid argument
  

  What complicated fffmpeg faerie magic is needed to make some of the filters other than volume controlled by a time-based expr?

• LL-HLS (CMAF/fMP4) minimize latency with FFplay

  16 mai, par DanielB6

  How do I minimize latency when streaming LL-HLS (CMAF/fMP4) via FFplay?

  I configured a live video stream which is broadcast from a media server using LL-HLS. I see the following results:

  • HLS.js: ~2 seconds behind the source
  • FFplay (./ffplay "https:////playlist.m3u8"): ~8 seconds behind the source
  • FFplay (./ffplay -fflags nobuffer -flags low_delay -strict experimental "https:////playlist.m3u8"): ~5 seconds behind the source

  My goal is to achieve what HLS.js can achieve in a browser, ~2 seconds behind the source.