[Vorbis] Re: [Flac] FLAC to Vorbis

[Dax Kelson]

On Wed, 2005-08-10 at 14:07 +1200, Aaron Whitehouse wrote:
> Hello everyone,
> 
> I am running Ubuntu and have converted my CDs to FLACs (using all the
> paranoia and fixing all the tags etc.). What is the best way for me to
> convert all of those FLAC to ogg-Vorbis files, keeping all the tag
> information and the same directory structure?

The tagging part is easy with modern version of oggenc. Also, oggenc can
read flac as an input file.

So the following will work, and preserve the tags:

oggenc -q 5 -o /tmp/cool-song.ogg /tmp/cool-song.flac

Neat eh?

About preserving the directory structure and allowing incremental runs
that only encode new flacs (or re-encode modified flacs) I found a
script on the net "flac2ogg.pl" that does what you want. It was written
for a windows cygwin environment but I modified to work on a native
UNIX/Linux system. Some of the perl is pretty ugly (like calling
external programs to do what perl can do natively), but hey it works.

Here it is:

#!/usr/bin/perl
#
# Copyright (c) 2004 - Jason L. Buberel - jason at buberel.org
# Licensed under the GNU GPL.
#
# Modified by Dax Kelson to run on a native UNIX/Linux box.

use Getopt::Long;
use File::stat;

$sourceDirPrefix = "/export/media/music/flacs";
$destDirPrefix = "/export/media/music/oggs";
$quality = 5;
GetOptions ( "source:s" => \$sourceDirPrefix,
             "dest:s" => \$destDirPrefix,
             "quality:i" => \$quality,
             "force" => \$force );

# Commands
$oggCommand = "oggenc";
$flacCommand = "flac";

@dirs = `cd "$sourceDirPrefix" && find . -type d -print`;
@files = `cd "$sourceDirPrefix" && find . -type f -name "*.flac" -print`;

# Check to see if our find command found anything to convert.
if ( scalar @files == 0 ) {
    die "Found no .flac files to convert!";
}

# recreate the directory hierarchy
foreach $dir (@dirs) {
    $dir =~ s/\n$//;
    $dir =~ s/^\.\///;

    # check to see if the destination dir already exists
    if ( !(stat ("$destDirPrefix/$dir")) ) {
        # stat failed so create the directory
        print "Creating output dir:\n   $destDirPrefix/$dir\n";
        $dir =~ s/\`/\'/g;
        $result = `cd "$destDirPrefix" && mkdir -p "$dir"`;
    }


}

# now process the actual sound files.
foreach $file (@files) {
    $file =~ s/\n$//;
    $file =~ s/^\.\///;

    # figure out what the destination file would be...
    $destinationFile = $file;
    $destinationFile =~ s/\.flac*/\.ogg/;

    # now stat the destinationFile, and see if it's date is more recent
    # than that of the original file. If so, we re-encode.
    # we also re-encode if the user supplied --force
    $srcInfo = stat ("$sourceDirPrefix/$file");
    $srcModTime = $srcInfo->mtime;
    $destInfo = stat ("$destDirPrefix/$destinationFile");
    if ( $destInfo ) {
        $destModTime = $destInfo->mtime;
        print "Skipping current file: $destDirPrefix/$destinationFile\n";
    }
    # if the destination file does not exist, or the user specified force,
    # or the srcfile is more recent then the dest file, we encode.
    if ( !$destInfo || $force || ( $srcModTime > $destModTime) ) {
        $file =~ s/\`/\'/g;
        $inFile = "$sourceDirPrefix/$file";
        $outFile = "$destDirPrefix/$destinationFile";
        $inFile =~ s/\0//g; $outFile =~ s/\0//g;
        $result =  `$oggCommand -q $quality -o "$outFile" "$inFile"`;
    }

}