Bash Scripts for Audio-Visual Preservation

It is easier to port a shell than a shell script.
~ Larry Wall

Bash AVpres is a set of Bash script for audio-visual preservation, used on a daily base at our conservation and restoration lab, AV Preservation by reto.ch. These small programs are designed for both to be used individually and to be chained each other as needed. The scripts are released under a 3-Clause BSD License and provided “as is” without warranty or support of any kind. Bug reports are very welcome, as usual.

Elements of the Set

Generate

• make a BagIt archive
• make a Matroska/FFV1 file
• make a MP4/H.264 file
• make a ProRes file
• make a checksum manifest
• make a frame MD5 checksum manifest

Verify

• verify a BagIt archive
• verify a Matroska/FFV1 file
• verify a checksum manifest
• verify a frame MD5 checksum manifest

Undo

• undo a BagIt archive

Other tools

• add, verify or remove a checksum as filename’s suffix
• find missing files in a folder of sequentially numbered files
• install, patch or delete FFmpeg HEAD
• install ffmprovisr recipes into FFCommand Engine (macOS and Windows Terminal or Subsystem for Linux)

Documentation

All the scripts come with a short embedded help message and the more complex ones also with a manual page (“man”). The command bash_avpres shows the list of the installed commands and manual pages.

Installation

The scripts can be run from everywhere, without any specific installation. Of course, they have to be executable; if they aren’t, run for example chmod +x bash_avpres or, when administrator privileges are requested, sudo chmod +x bash_avpres.

In addition, two possibilities are provided for a regular installation at the root: via a Homebrew formula and via a Makefile.

Homebrew

Run the following two commands in the Terminal:

brew tap avpres/formulae
brew install avpres/formulae/bash-avpres

Makefile

As usual, classical directions are recalled in the README.txt file: run the following three commands in the Terminal:

cd bash-avpres-YYYY-MM-DD
./configure
make install

Compatibility

The Bash AVpres scripts have been used successfully on various modern x86_64 architectures running under the following operating systems:

• Linux: Debian 10.6 and 9.13; Ubuntu 20.04.1 LTS, 18.04.5 LTS and 16.04.7 LTS; Slackware 14.2; Qubes OS 4.0.3
• Macintosh: 11.0 public beta 5, 10.15.7, 10.14.6 and 10.13.6
• Windows 10: version 2004, 1909, 1903 and 1809, running Terminal or Subsystem for Linux

The scripts have been programmed to run also on the old Bash version 3.2 (released on 2006–10–11), which sadly still comes with the Apple computers. However, we strongly advise to install the current Bash version 5.0 (released on 2019–01–07) also on computers running under macOS.

Source Code

The source code of the Bash AVpres package is available on our website as a “.tar.gz” file, a TAR archive which was compressed with gzip.

2020–10-23