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• Encrypted HLS works as live stream, doesn't work as VOD

  22 avril 2015, par Misiur

  I’ve found some crude bash script for encoding and encrypting video file, into a HLS stream, and I’ve edited it slightly (I have no idea about bash) :

  #!/bin/bash
  
  
  
  set -e     # Exit on errors
  
  
  
  tsFile="$1"
  
  
  
  if ! [ -f "$tsFile" -a -r "$tsFile" ]; then
  
      echo "First argument is required" >&2
  
      exit 2
  
  fi
  
  
  
  if [ -z "$3" ]; then
  
      output="output"
  
  else
  
      output="$3"
  
  fi
  
  
  
  
  
  keyFile="$output.key"
  
  keyInfoFile="$output.keyinfo"
  
  playList="$output.m3u8"
  
  
  
  if [ -z "$4" ]; then
  
      separator='-'
  
  else 
  
      separator="$4"
  
  fi
  
  
  
  splitFilePrefix="$output$separator"
  
  
  
  
  
  if [ -d "$2" ]; then
  
      outDir="$2"
  
  else
  
      mkdir "$2" || exit 1
  
      outDir="$2"
  
  fi
  
  
  
  tempDir="$outDir/.$$_tmp"
  
  keyFile="$outDir/$keyFile"
  
  
  
  mkdir $tempDir
  
  
  
  echo "$outdir/$keyFile\n$outdir/$keyFile" > "$outdir/$keyInfoFile"
  
  
  
  
  
  ffmpeg -i "$tsFile" -hls_time 5 -hls_list_size 0 -hls_segment_filename "$tempDir/$splitFilePrefix%03d.ts" -strict -2 "$tempDir/$playList"
  
  
  
  openssl rand 16 > $keyFile
  
  encryptionKey=`cat $keyFile | hexdump -e '16/1 "%02x"'`
  
  
  
  numberOfTsFiles=$(( `ls "$tempDir/$splitFilePrefix"*.ts | wc -l` -1 ))
  
  
  
  for i in $(seq -f "%03g" 0 $numberOfTsFiles); do
  
      initializationVector=`printf '%032x' $(( 10#$i))`
  
      openssl aes-128-cbc -e -in "$tempDir/$splitFilePrefix"$i.ts \
  
      -out "$outDir/$splitFilePrefix"$i.ts -nosalt -iv $initializationVector -K $encryptionKey
  
  done
  
  
  
  {
  
      head -4 "$tempDir/$playList"
  
      echo '#EXT-X-KEY:METHOD=AES-128,URI='"$keyFile"
  
      egrep "$tempDir/$playList" -vie '#EXT-X-TARGETDURATION:' \
  
      | tail -n +4
  
  } > "$outDir/$playList"
  
  
  
  #rm -r "$tempDir"

  This results in a something like this :

  #EXTM3U
  
  #EXT-X-VERSION:3
  
  #EXT-X-MEDIA-SEQUENCE:0
  
  #EXT-X-KEY:METHOD=AES-128,URI=output.key
  
  #EXT-X-TARGETDURATION:11
  
  #EXTINF:10.176833,
  
  output-000.ts
  
  #EXTINF:8.341667,
  
  output-001.ts
  
  #EXTINF:8.341667,
  
  output-002.ts
  
  #EXTINF:3.136467,
  
  output-003.ts
  
  #EXT-X-ENDLIST

  This almost works. However I need an VOD, not a live stream. So, I added line :

  #EXT-X-PLAYLIST-TYPE:VOD

  And now it doesn’t work with encrypted segments, only with unencrypted ones. I thought all segments are crypted separately ? Also, even with unencrypted files, the info about total length isn’t present. How can I fix that ?

• ffmpeg library does not work from path but directly

  19 juin 2020, par Ángel Barrios

  I want to add a watermark to a video.

  



  I'm trying with windows 10 and ffmpeg library

  



  The command I am using.

  



  ffmpeg -i example.mp4 -i watermark.png  -filter_complex "overlay=0-0+0:main_h-overlay_h-0+0" watermark.mp4


  



  When I use it this way accesing the path I get this error :

  



  

  



  But when I execute it not from path but opening cmd right on the executable folder it works fine

  



  I did some research and couldn't find the answers I was looking for.

  



  Why does this happen ? I can´t understand really

  



  Thank you !

  


• Why review compositing work in MJPEG videos rather than (say) H.264 ?

  6 juin 2016, par d3vid

  I have received a request to encode DPX files to MOV/MJPEG rather than MOV/H.264 (which ffmpeg picks by default if you convert to output.mov). These is to review compositing renders (in motion), so color accuracy is critical.

  Comparing a sample "ideal" MOV to the current (H.264) output I can see :

  • resolution : the same
  • ColorSpace/Primaries : Rec609 (SD) versus Rec709 (HD)
  • YUV : 4:2:0 versus 4:4:4
  • filesize : smaller

  The ffmpeg default seems to be better quality and result in a smaller filesize. Is there something I’m missing ?