What if you need to play a JW.ORG video file with the neighbor sign language and the audio from another hearing language.
You can do it. All you just need is to download that video in both the sign language and the hearing language that you need and having the Ffmpeg1 on your computing devices.
Ffmpeg can be installed on multiple platforms:
- Windows via Chocolatey
- macOS via Homebrew
- iOS/iPadOS by
apk add ffmpegin iSH Shell
- Android by
pkg install ffmpegin Termux
Below are two ways to do that using Ffmpeg:
One is to extract audio from the hearing language video file.
ffmpeg -i HearingLanguage-VideoFile_r720P.mp4 -vn -acodec copy Output-AudioOnlyFile.aac
And then, using the audio file above to replace the audio of the sign language video file.
ffmpeg -i SignLanguage-VideoFile_r720P.mp4 -i Output-AudioOnlyFile.aac -map 0:v -map 1:a -c copy -y Output-AudioVideoFile_r720P.mp4
Or, we replace two lines above by one line below.
ffmpeg -an -i SignLanguage-VideoFile_r720P.MP4 -vn -i HearingLanguage-VideoFile.MP4 -map 0:v -map 1:a -c:v copy -c:a copy Output-AudioVideoFile_r720P.mp4
These lines force Ffmpeg not to re-encode, so that the quality of the sourced video and audio are untouched. Also, the metadata is cloned from the sign language video file, you can rename the output file exactly as the sign language video file to import it back to JW Library Sign Language app via the Import File feature.2
Please keep in mind that all the material on JW.ORG is copyrighted. No ones should post publications of Jehovah’s Witnesses on a personal website or on social media.3