Matthias brutella

How to convert m4a files to mp3, preserving bitrate and id3 tags using ffmpeg

Prerequisites

ffmpeg
cygwin (on windows)

Commands

cd /path/to/m4a/files
mkdir out
for f in *.m4a; do

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Install Rasbian

Most of the time I use a headless Raspberry Pi which I want to access via ssh. These are the steps to do that.

Download Rasbian
Install the downloaded file on a SD card

Find the disk number of the SD card with diskutil list
Unmount the disk with diskutil unmountDisk /dev/disk<number>
Copy data on the SD card with sudo dd bs=1m if=<img-file> of=/dev/rdisk<number> conv=sync

	[color]
	ui = auto
	[color "branch"]
	current = yellow reverse
	local = yellow
	remote = green
	[color "diff"]
	meta = yellow bold
	frag = magenta bold
	old = red bold

	a: AM/PM
	A: 0~86399999 (Millisecond of Day)

	c/cc: 1~7 (Day of Week)
	ccc: Sun/Mon/Tue/Wed/Thu/Fri/Sat
	cccc: Sunday/Monday/Tuesday/Wednesday/Thursday/Friday/Saturday

	d: 1~31 (0 padded Day of Month)
	D: 1~366 (0 padded Day of Year)

	// Based upon code from Apple's "GenericKeychain" sample application

	/*
	File: KeychainItemWrapper.h
	Abstract:
	Objective-C wrapper for accessing a single keychain item.

	Version: 1.2

	Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple

	# Set variables in .bashrc file

	# don't forget to change your path correctly!

	export GOPATH=$HOME/golang
	export GOROOT=/usr/local/opt/go/libexec
	export PATH=$PATH:$GOPATH/bin
	export PATH=$PATH:$GOROOT/bin

	//
	// Activity.swift
	//
	// Created by Zachary Waldowski on 8/21/16.
	// Copyright © 2016 Zachary Waldowski. Licensed under MIT.
	//

	import os.activity

	private final class LegacyActivityContext {

	<?xml version="1.0" encoding="UTF-8"?>
	<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
	<plist version="1.0">
	<!-- iOS 10, macOS Sierra, and friends bring a new logging subsystem that's
	supposed to scale from the kernel, up to frameworks, and up to apps. It defaults
	to a more regimented, privacy-focused approach that large apps and complex
	systems need.

	It, along with Activity Tracing introduced in iOS 8 and macOS Yosemite and the
	Console app in macOS Sierra, hope to help you graduate from caveman debugging to

	<?xml version="1.0" encoding="utf-8"?>
	<xs:schema xmlns:knx="http://knx.org/xml/project/11" xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace="http://knx.org/xml/project/11" elementFormDefault="qualified" attributeFormDefault="unqualified" version="1.0">
	<!-- Simple types -->
	<xs:simpleType name="IDREF">
	<xs:restriction base="xs:NCName"/>
	</xs:simpleType>
	<xs:simpleType name="IDREFS">
	<xs:list itemType="knx:IDREF"/>
	</xs:simpleType>
	<xs:simpleType name="Capabilities_t">