manifesto

Manifesto

Manifesto is an HLS tool for creating multiple variants, a master.m3u8 file, and converting 608 captions to segmented webvtt subtitles via ffmpeg.

Setup

Required

• Go
• Ffmpeg

Install go

  https://golang.org/doc/install

Set your Environment

mkdir  ~/go
export GOPATH=~/go

Add one library

go get -u github.com/logrusorgru/aurora

Install ffmpeg with libx264 support

Git clone the repo

git clone https://github.com/gitfu/manifesto
cd manifesto
go build manifesto.go

How It Works

Manifesto transcodes and segments video into multiple variants and creates the master.m3u8 file. 608 Closed captions are extracted and converted to webvtt segment files.

Quick Start

• cd ~/manifesto
• ./manifesto -i vid.ts

This will create the following directory structure and files

vid:
hd720  low640  master.m3u8  med960  subs

vid/med960:
index0.ts  index1.ts  index2.ts  index3.ts  index4.ts  index.m3u8

vid/hd720:
index0.ts   index1.ts   index2.ts   index3.ts   index4.ts   index.m3u8

vid/low640:
index0.ts   index1.ts   index2.ts   index3.ts   index4.ts   index.m3u8

vid/subs:
index0.vtt  index1.vtt  index2.vtt  index3.vtt  index4.vtt  index_vtt.m3u8

• The default toplevel directory name is the video file name without the file extention.
• The variants are read from the hls.json file, variants can be added or removed as needed.
• The command used to traanscode is specified in the cmd.template file, it can be modified.

Command line switches

  -d string
    	override top level directory for hls files (optional)
  -i string
    	Video file to segment (either -i or -b is required)
  -j string
    	JSON file of variants (optional) (default "./hls.json")
  -s string
    	subtitle file to segment (optional)
  -t string
    	command template file (optional) (default "./cmd.template")
  -u string
    	url prefix to add to index.m3u8 path in master.m3u8 (optional)

Usage

./manifesto -i vid.mp4

• This is single mode a master.m3u8 and variants will be created in a new directory named vid. It will also attempt to extract 608 captions and convert them to segmented webvtt subtitles.

./manifesto -i vid.mp4 -s sub.srt

• As above but instead of extracting 608 captions, sub.srt will be converted to a webvtt file and then segmented.

./manifesto -i vid.mp4 -s sub.srt -u http://example.com

• As above and also adds the url prefix to each variant listed in the m3u8 file.

How to Modify

• manifesto works right of the box.I wanted it to be easy to use with minimal configuation needed. If you do feel the need to tune it a bit.

Variants

• Variant data is stored in the hls.json file.
• Add or edit or remove as desired.

[
{"name": "med960", "aspect": "960x540", "framerate":"29.97","vbitrate": "2000","bufsize":"4000","abitrate": "96k"}
,{"name": "low640", "aspect": "640x360", "framerate":"29.97","vbitrate": "730","bufsize":"1460","abitrate": "64k"}
,{"name":"hd720","aspect": "1280x720", "framerate" :"29.97","vbitrate": "4500","bufsize":"9000","abitrate": "128k"}
]

Modifying The Ffmpeg Command

• cmd.template is the default ffmeg command template
• NAME,ASPECT,FRAMERATE,VBITRATE,BUFSIZE,ABITRATE will be replaced with variant's values from hls.json.
• Newlines are stripped.

Values in the master.m3u8 file

The values used in the master.m3u8 file are read an /or calculated for each variant as follows.

• Bandwidth ( bit_rate is parsed the mpegts container )
• Resolution ( width and height for the video resolution are parsed from the video stream)
• Level ( video level is parsed from the video stream )
• Profile (video profile is parsed from the video stream, audio profile from the audio stream)
• Codecs (Calculated as described here https://developer.apple.com/library/content/documentation/NetworkingInternet/Conceptual/StreamingMediaGuide/FrequentlyAskedQuestions/FrequentlyAskedQuestions.html )

#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=%v,RESOLUTION=%s,CODECS=\"avc1.%v00%x%v\""