yading@11: #!/usr/bin/env perl
yading@11: 
yading@11: # Copyright (c) 2012 Nicolas George
yading@11: #
yading@11: # This file is part of FFmpeg.
yading@11: #
yading@11: # FFmpeg is free software; you can redistribute it and/or
yading@11: # modify it under the terms of the GNU Lesser General Public
yading@11: # License as published by the Free Software Foundation; either
yading@11: # version 2.1 of the License, or (at your option) any later version.
yading@11: #
yading@11: # FFmpeg is distributed in the hope that it will be useful,
yading@11: # but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
yading@11: # See the GNU Lesser General Public License for more details.
yading@11: #
yading@11: # You should have received a copy of the GNU Lesser General Public License
yading@11: # along with FFmpeg; if not, write to the Free Software Foundation, Inc.,
yading@11: # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11: 
yading@11: =head1 NAME
yading@11: 
yading@11: make_chlayout_test - produce a multichannel test file with the channels
yading@11: clearly identified
yading@11: 
yading@11: =head1 SYNOPSIS
yading@11: 
yading@11: tools/make_chlayout_test I<channels> I<out_options>
yading@11: 
yading@11: =head1 DESCRIPTION
yading@11: 
yading@11: This script uses B<ffmpeg> and B<libflite> to produce a file with audio
yading@11: channels clearly identified by their name. The resulting file can be used to
yading@11: check that the layout and order of channels is correctly handled by a piece
yading@11: of software, either a part of B<FFmpeg> or not.
yading@11: 
yading@11: I<channels> is a list of channels or channel layouts, separated by '+'.
yading@11: 
yading@11: I<out_options> is a list of valid ffmpeg outout options, including the
yading@11: output file.
yading@11: 
yading@11: Note that some output codecs or formats can not handle arbitrary channel
yading@11: layout.
yading@11: 
yading@11: This script requires a B<ffmpeg> binary, either in the source tree or in the
yading@11: search path; it must have the flite audio source enabled.
yading@11: 
yading@11: =head1 EXAMPLES
yading@11: 
yading@11: Check that the speakers are correctly plugged:
yading@11: 
yading@11:   tools/make_chlayout_test FL+FR -f alsa default
yading@11: 
yading@11: Produce a 5.1 FLAC file:
yading@11: 
yading@11:   tools/make_chlayout_test 5.1 surround.flac
yading@11: 
yading@11: =cut
yading@11: 
yading@11: use strict;
yading@11: use warnings;
yading@11: use Getopt::Long ":config" => "require_order";
yading@11: use Pod::Usage;
yading@11: 
yading@11: GetOptions (
yading@11:   "help|usage|?|h" => sub { pod2usage({ -verbose => 1, -exitval => 0 }) },
yading@11:   "manpage|m"      => sub { pod2usage({ -verbose => 2, -exitval => 0 }) },
yading@11: ) and @ARGV >= 2 or pod2usage({ -verbose => 1, -exitval => 1 });
yading@11: 
yading@11: my $channels = shift @ARGV;
yading@11: my @out_options = @ARGV;
yading@11: 
yading@11: my $ffmpeg = exists $ENV{FFMPEG} ? $ENV{FFMPEG} :
yading@11:              $0 =~ /(.*)\// && -e "$1/../ffmpeg" ? "$1/../ffmpeg" :
yading@11:              "ffmpeg";
yading@11: 
yading@11: my %channel_label_to_descr;
yading@11: my %layout_to_channels;
yading@11: 
yading@11: {
yading@11:   open my $stderr, ">&STDERR";
yading@11:   open STDERR, ">", "/dev/null";
yading@11:   open my $f, "-|", $ffmpeg, "-layouts" or die "$ffmpeg: $!\n";
yading@11:   open STDERR, ">&", $stderr;
yading@11:   while (<$f>) {
yading@11:     chomp;
yading@11:     next if /^NAME/ or /:$/ or /^$/; # skip headings
yading@11:     my ($name, $descr) = split " ", $_, 2;
yading@11:     next unless $descr;
yading@11:     if ($descr =~ /^[[:upper:]]+(?:\+[[:upper:]]+)*$/) {
yading@11:       $layout_to_channels{$name} = [ split /\+/, $descr ];
yading@11:     } else {
yading@11:       $channel_label_to_descr{$name} = $descr;
yading@11:     }
yading@11:   }
yading@11: }
yading@11: 
yading@11: my @channels = map { @{$layout_to_channels{$_} // [$_]} } split /\+/, $channels;
yading@11: 
yading@11: my $layout = join "+", @channels;
yading@11: my $graph = "";
yading@11: my $concat_in = "";
yading@11: for my $i (0 .. $#channels) {
yading@11:   my $label = $channels[$i];
yading@11:   my $descr = $channel_label_to_descr{$label}
yading@11:     or die "Channel $label not found\n";
yading@11:   $graph .= "flite=text='${descr}', aformat=channel_layouts=mono, " .
yading@11:             "pan=${layout}:${label}=c0 [ch$i] ;\n";
yading@11:   $concat_in .= "[ch$i] ";
yading@11: }
yading@11: $graph .= "${concat_in}concat=v=0:a=1:n=" . scalar(@channels);
yading@11: 
yading@11: exec $ffmpeg, "-f", "lavfi", "-i", $graph, @out_options
yading@11:   or die "$ffmpeg: $!\n";