JavaScript History as Seen From 2035

Gary Bernhardt presents a thought-provoking history of JavaScript as seen from 2035.

His arguments are that

  • With asm.js JavaScript VMs ran code with 50% of native speed (even in 2013)
  • Anything that can be compiled can be compiled into asm.js
  • Asm.js has basically become the universal runtime

So by further moving the JavaScript VM into the kernel we save ourselves the overhead of hardware process isolation as the VM does this any way.

All this lead to interesting consequences

  • Nobody uses binaries any more, everything is asm.js
  • The windowing systems of old have been ported to the DOM
  • Deployments are as simple as a push
  • JavaScript (as a language) is effectively dead
  • Overall developer happiness has increased

:’D

Convert any file VLC can play to mp3

I just felt the need for a script that could extract the audio track of a video, transcode it and save it as an mp3 file … 2 hours later I was finished (get the Gist). 😀 It uses VLC to do hard work. 😉

Thanks to Kris Hom for the inspiration. 🙂

#!/usr/bin/env ruby -rubygems
#
# Author: Riyad Preukschas <riyad@informatik.uni-bremen.de>
# License: Mozilla Public License 2.0
#
# Transcode any file ffmpeg can play to mp3.
require 'optparse'
require 'shellwords'
#
# helpers
#
def puts_error(message)
puts "Error: #{message}"
end
def puts_warning(message)
puts "Warning: #{message}"
end
#
# parse options
#
options = {
:bit_rate => 192,
}
begin
OptionParser.new do |opts|
opts.banner = "Usage: convert2mp3 [options] FILE [<FILE ...>]"
opts.separator ""
opts.separator "Conversion Options:"
opts.on("-f", "--[no-]force", "Overwrite mp3 file if it exists already") do |f|
options[:force_overwrite] = f
end
opts.on("-o", "--output-directoy [DIRECTORY]", "Save converted files to this directory") do |out_dir|
unless File.directory?(out_dir)
puts_error %Q(Wrong output directory. "#{out_dir}" is not a directory.)
exit 1
end
options[:output_dir] = out_dir
end
opts.separator ""
opts.separator "mp3 Options:"
opts.on("-b", "--bit-rate [RATE]", Integer, "Bit rate in kbit/s (default: #{options[:bit_rate]})") do |b|
options[:bit_rate] = b
end
opts.separator ""
opts.separator "General Options:"
opts.on_tail("-h", "--help", "Show this message") do
puts opts
exit 0
end
opts.on_tail("-v", "--[no-]verbose", "Be more verbose") do |v|
options[:verbose] = v
end
end.parse!
rescue OptionParser::InvalidOption => e
puts_error e.message
exit 1
end
#
# gather source files
#
if ARGV.empty?
puts_error "No files given."
exit 1
end
source_files = []
while !ARGV.empty?
source_path = ARGV.shift
unless File.exists?(source_path)
puts_warning %Q(Skipping "#{source_path}". It doesn't exist.)
next
end
unless File.file?(source_path)
puts_warning %Q(Skipping "#{source_path}". It's not a file.)
next
end
source_files << source_path
end
#
# ffmpeg command line options
#
FFMPEG = 'ffmpeg'
TRANSCODING = '-vn -ab BIT_RATEk -vbr on -f mp3'.
gsub('BIT_RATE', options[:bit_rate].to_s)
VERBOSITY = options[:verbose] ? '-v info' : '-v quiet'
if `which #{FFMPEG} > /dev/null` && $? != 0
puts_error "Couldn't find ffmpeg."
exit 1
end
source_files.each do |source_file|
source_dir = File.dirname(source_file)
output_dir = options[:output_dir] || source_dir
output_file = File.join(output_dir, "#{File.basename(source_file, ".*")}.mp3")
if File.exist?(output_file)
if options[:force_overwrite]
puts_warning %Q(Output file exists. "#{output_file}" will be overwritten.) if options[:verbose]
else
puts_warning %Q(Output file exists already. Skipping "#{output_file}".)
next
end
end
puts %Q(Converting "#{source_file}")
unless system("#{FFMPEG} #{VERBOSITY} -y -i #{source_file.shellescape} #{TRANSCODING} #{output_file.shellescape}")
puts_error "Conversion failed. Try using the -v option for more detailed output."
end
puts if options[:verbose]
end
#!/usr/bin/env ruby -rubygems
#
# Author: Riyad Preukschas <riyad@informatik.uni-bremen.de>
# License: Mozilla Public License 2.0
#
# Transcode any file VLC can play to mp3.
require 'optparse'
require 'mkmf'
require 'shellwords'
#
# helpers
#
def puts_error(message)
puts "Error: #{message}"
end
def puts_warning(message)
puts "Warning: #{message}"
end
#
# parse options
#
options = {
:bit_rate => 192,
:sampling_rate => 44100,
}
begin
OptionParser.new do |opts|
opts.banner = "Usage: convert2mp3 [options] FILE [<FILE ...>]"
opts.separator ""
opts.separator "Conversion Options:"
opts.on("-f", "--[no-]force", "Overwrite mp3 file if it exists already") do |f|
options[:force_overwrite] = f
end
opts.on("-o", "--output-directoy [DIRECTORY]", "Save converted files to this directory") do |out_dir|
unless File.directory?(out_dir)
puts_error %Q(Wrong output directory. "#{out_dir}" is not a directory.)
exit 1
end
options[:output_dir] = out_dir
end
opts.separator ""
opts.separator "mp3 Options:"
opts.on("-b", "--bit-rate [RATE]", Integer, "Bit rate in kbit/s (default: #{options[:bit_rate]})") do |b|
options[:bit_rate] = b
end
opts.on("-s", "--sampling-rate [RATE]", Integer, "Sampling rate in Hz (default: #{options[:sampling_rate]})") do |s|
options[:sampling_rate] = s
end
opts.separator ""
opts.separator "General Options:"
opts.on_tail("-h", "--help", "Show this message") do
puts opts
exit 0
end
opts.on_tail("-v", "--[no-]verbose", "Be more verbose") do |v|
options[:verbose] = v
end
end.parse!
rescue OptionParser::InvalidOption => e
puts_error e.message
exit 1
end
#
# gather source files
#
if ARGV.empty?
puts_error "No files given."
exit 1
end
source_files = []
while !ARGV.empty?
source_path = ARGV.shift
unless File.exists?(source_path)
puts_warning %Q(Skipping "#{source_path}". It doesn't exist.)
next
end
unless File.file?(source_path)
puts_warning %Q(Skipping "#{source_path}". It's not a file.)
next
end
source_files << source_path
end
#
# VLC command line options
#
# using find_executable() will create a mkmf.log file :(
vlc_paths = [
'vlc',
'/Applications/VLC.app/Contents/MacOS/VLC',
File.expand_path('~/Applications/VLC.app/Contents/MacOS/VLC'),
]
VLC = vlc_paths.find { |path| find_executable0(path) }
INTERFACE = '-I dummy'
PLAYBACK = '--no-loop --no-repeat --play-and-exit'
TRANSCODING = '--sout="#transcode{vcodec=dummy,acodec=mp3,ab=BIT_RATE,channels=2,samplerate=SAMPLING_RATE}:standard{access=file,mux=raw,dst=\'DESTINATION\'}"'.
gsub('BIT_RATE', options[:bit_rate].to_s).
gsub('SAMPLING_RATE', options[:sampling_rate].to_s)
VERBOSITY = options[:verbose] ? '' : '-q 2>/dev/null 1>/dev/null'
if VLC.nil?
puts_error "Couldn't find VLC."
exit 1
end
source_files.each do |source_file|
source_dir = File.dirname(source_file)
output_dir = options[:output_dir] || source_dir
output_file = File.join(output_dir, "#{File.basename(source_file, ".*")}.mp3")
if File.exist?(output_file)
if options[:force_overwrite]
puts_warning %Q(Output file exists. "#{output_file}" will be overwritten.) if options[:verbose]
else
puts_warning %Q(Output file exists already. Skipping "#{output_file}".)
next
end
end
puts %Q(Converting "#{source_file}")
unless system("#{VLC} #{PLAYBACK} #{INTERFACE} #{TRANSCODING.gsub('DESTINATION', output_file.gsub(/'/, ""))} #{source_file.shellescape} #{VERBOSITY}")
puts_error "Conversion failed. Try using the -v option for more detailed output."
end
puts if options[:verbose]
end

Update 2014-03-01:

  • Check whether VLC is installed
  • Should also work on Linux now
  • Increase default bit rate to 192kbit/s
  • Fixed bug where the file/playlist would repeat endlessly

Update 2014-11-05:

  • Also look for VLC in “~/Application/”

Update 2016-03-05