Generates a collage based on a set of videos

.dockerignore

video_files_by_sha1
output
*.pyc

README.md

HSŁ collage generator - build instructions

1. Download this gist as a git repository
2. Pull a .zip file with all contents of this directory: https://drive.google.com/drive/folders/1cJVElo-6QvkmIRygEhOTOfhQd87Ocmnz?usp=sharing
3. Unzip the directory so that the git checkout contains video_files_by_sha1 directory that has .mp4 files directly in it
4. Run sudo docker-compose up --build, wait about a minute
5. The output you're looking for is in output/collage.mp4.

docker-compose.yml

version: '3.0'
services:
  collage:
    build: .
    volumes:
      - ./video_files_by_sha1:/video_files_by_sha1
      - ./output:/output

Dockerfile

FROM python:3.11
RUN apt-get update && apt-get install -y ffmpeg && rm -rf /var/lib/apt/lists/* /var/cache/apt/*
ADD ./main.py .
CMD ["python", "main.py"]

main.py

#!/usr/bin/env python3

import subprocess
import pathlib


def ffmpeg_collage(fname1, fname2, fname3, fname4, outfname, length_sec=1):
    subprocess.call(
        [
            "ffmpeg",
            "-i",
            fname1,
            "-i",
            fname2,
            "-i",
            fname3,
            "-i",
            fname4,
            "-filter_complex",
            "nullsrc=size=640x480 [base];"
            " [0:v] setpts=PTS-STARTPTS, scale=320x240 [upperleft];"
            " [1:v] setpts=PTS-STARTPTS, scale=320x240 [upperright];"
            " [2:v] setpts=PTS-STARTPTS, scale=320x240 [lowerleft];"
            " [3:v] setpts=PTS-STARTPTS, scale=320x240 [lowerright];"
            " [base][upperleft] overlay=shortest=1 [tmp1];"
            " [tmp1][upperright] overlay=shortest=1:x=320 [tmp2];"
            " [tmp2][lowerleft] overlay=shortest=1:y=240 [tmp3];"
            " [tmp3][lowerright] overlay=shortest=1:x=320:y=240",
            "-t",
            str(length_sec),
            "-c:v",
            "libx264",
            outfname,
        ]
    )


def write_list_of_files():
    list_of_files = list(pathlib.Path("/output").glob("*.mp4"))
    with open("/output/files.txt", "w") as f:
        for fh in list_of_files:
            f.write(f"file '{fh.name}'\n")


def concatenate_files():
    subprocess.call(
        [
            "ffmpeg",
            "-f",
            "concat",
            "-safe",
            "0",
            "-i",
            "/output/files.txt",
            "-c",
            "copy",
            "/output/collage.mp4",
        ]
    )


def create_chunks_of_four():
    list_of_files = list(pathlib.Path("/video_files_by_sha1").glob("*.mp4"))
    chunks_of_four = [
        list_of_files[i : i + 4] for i in range(0, len(list_of_files), 4)
    ]
    for chunk in chunks_of_four:
        if len(chunk) < 4:
            continue
        ffmpeg_collage(
            chunk[0],
            chunk[1],
            chunk[2],
            chunk[3],
            "/output/" + "".join([f.name for f in chunk]) + ".mp4",
        )


def main():
    create_chunks_of_four()
    write_list_of_files()
    concatenate_files()


if __name__ == "__main__":
    main()

pyproject.toml

[tool.black]
line-length = 79
target-version = ['py37']