Project Name

Auxilary tools and solution for pre/post processing of audio and video based on ffmpeg

General info

all the processing should be able to do in Colab environment with all its advantages and constrains

• Function for downloading and saving m3u8 stream to mp4 file with given length per a piece in Colab
• snippet for cuuting/triming video with recompilation to avoid problems with broken frames
• snippets to slow down speed up audion

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Colab

Colab is conviniet when you dont care about privacy though for some operations with private file like changing converting your private videos I recomend using ffmpeg on local machine. Someone could say that installing whole environment could take a while and will not be so simple. Then what for once you have docker some ready to use image and then temporary container could be utilised.

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Local with docker

I need to mention here excellent work of the Julien Rottenberg's team
https://github.com/jrottenberg/ffmpeg

You can install the latest build of this image by running:

docker pull jrottenberg/ffmpeg:${VERSION}-${VARIANT} or docker pull ghcr.io/jrottenberg/ffmpeg:${VERSION}-${VARIANT}.

Example which is converting high resolution video to from handy to some rescaled mp4 640x ... is below( working like charm)

docker run --rm -d -v $(pwd):$(pwd) -w $(pwd) --name mp4-converter jrottenberg/ffmpeg:4.4-ubuntu -i /mnt/c/docker_out/ffmpeg/dzia/po3.mp4 -vf scale=640:-1 /mnt/c/docker_out/ffmpeg/dzia/_po3.mp4

excellent guides are there but giving short info about my example after -i( interactive) flag is path with input file /mnt/c/docker_out/ffmpeg/dzia/po3.mp4 and otput file _/mnt/c/docker_out/ffmpeg/dzia/po3.mp4

If there is need to convert whole directory this time (to change a bit subject convertig mp3 to wav format) then preparing some bash script where docker converter is inside do the job. Content of the script could be as follows:

for i in *.mp4;

	do	docker run --rm -d -v $(pwd):$(pwd) -w $(pwd) --cpus 3 --name "$i" jrottenberg/ffmpeg:4.4-ubuntu -i "$i" -b:v 1M  "$(basename "$i" .mp4)"_re.mp4  ;
	name=`echo "$i" | cut -d'.' -f1`;
	echo "$name"	;

	sleep 1
done

You need to be careful with allocating resources in this case CPU( --cpus 3) I limited that to 3 ( it is not particularly memory intensive process convertig 200MB file to 1Mb rate uses ~300MB memory. Once you allocate resources batch will take care about whole process utilising machine resources withing given limit.

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Technologies

• Python,
• ffmpeg,
• docker,
• bash,

Setup

easiest is to install/update libraries accordnig to install secion in notebook

Status

Project is: in progress

Other information

Notebook is divided on universal fuctions whicht could be easlily used elsewhere.

Contact

Created by: lencz.sla@gmail.com