Tool for creating a m3u8 playlist file out of a folder of fragmented AV files (.ts).

create-m3u8-from-folder.ts

/**
 * Example usages
 * 
 * deno run -A LINK_TO_RAW_OF_THIS_GIST
 * 
 * deno run -A LINK_TO_RAW_OF_THIS_GIST \
 *  --path "/path/to/your/folder/with/data"
 * 
 * deno run -A LINK_TO_RAW_OF_THIS_GIST \
 *  --path "/path/to/your/folder/with/data" \
 *  --name "customname.m3u8"
 * 
 * deno run -A LINK_TO_RAW_OF_THIS_GIST \
 *  --name "customname.m3u8"
 * 
 * 
 * 
 * Manual
 * 
 * Tool for creating a m3u8 playlist file out of a folder of fragmented AV files (.ts).
 * The main use-case of this script is to link together fragments after you've got
 * a recording in obs and it is known to create wrong playlist file (.m3u8).
 * This script assumes:
 * Your fragment files have `.ts` extension.
 * Your fragment files have ordering suffix after a dash.
 * Your fragment files are in a single directory.
 * In short, those are first 3, then 100th, 101th and n segment file:
 *  `something-0.ts`,
 *  `something-1.ts`,
 *  `something-2.ts`,
 *  ...
 *  `something-99.ts`,
 *  `something-100.ts`,
 *  ...
 *  `something-n.ts`
 * 
 * In my case, I am recording my daily streams and my obs configuration is as follows:
 * Settings/Output/Recording:
 *  Recording path: `/home/user/Videos/streams/`
 *  Recording format: `HLS(.m3u8 + .ts)`
 * Settings/Advanced/Recording:
 *  Filename Formatting: `%CCYY-%MM-%DD/%CCYY-%MM-%DD %hh-%mm-%ss`
 *
 * Optional arguments:
 * --path <path>  Path to a single directory, without leading slash, can be absolute,
 *                defaults to `.`
 * --name <name>  Name of generated playlist file, it is saved in the same directory as
 *                your path argument points to, defaults to `playlist.m3u8`
 *
 */

import { parseArgs } from "https://deno.land/std@0.207.0/cli/parse_args.ts";

const args = parseArgs(Deno.args, {
  string: ["path", "name"]
});

const path = args.path || ".";
const name = args.name || "playlist.m3u8";

const fileIterator = Deno.readDirSync(path)
const fileArrayUnsorted = [...fileIterator];

type SegmentFileEntry = Deno.DirEntry & {
  segmentName: string;
  last: number;
}

const segmentArray = fileArrayUnsorted
  .filter(({ name }) => {
    return name.includes(".ts");
  })
  .map((data): SegmentFileEntry => {
    const [segmentName] = data.name.split(".ts");
    const last = segmentName.split("-").pop()!;
    return {
      ...data,
      segmentName,
      last: +last
    };
  })
  .sort((a, b) => {
    return a.last - b.last;
  });

const duration = 2;
const header = `
#EXTM3U
#EXT-X-VERSION:3
#EXT-X-TARGETDURATION:${duration}
#EXT-X-MEDIA-SEQUENCE:2426
`;
const suffix = `
#EXT-X-ENDLIST
`;
const item = (name: string) => `
#EXTINF:2.000000,
${name}
`;

const result = `
${header}
${segmentArray.map(({name}) => item(name)).join("")}
${suffix}
`
  .split("\n")
  .filter(line => line !== "")
  .join("\n")

Deno.writeTextFileSync(`${path}/${name}`, result);