makeWebAudio.sh
author Jim Hague <jim.hague@acm.org>
Fri, 13 Oct 2017 15:44:15 +0100
changeset 748 ce5c7214f9aa
parent 567 cb7a4eff9d5b
child 753 b83b49f2a0a0
permissions -rwxr-xr-x
Introduce mechanism for having different tune images for compact printed output. Sort alternate .abc in subdir 'Compact' under the booke dir. Use that as the graphic for A5 output, assuming it will be vertically more compact. Use Bear Dance as an example, as it has commentary that currently overflows an A5 landscape page. For the moment, transposed Bookes don't transpose and so don't use Compact.

#!/bin/bash
#
# Make audio required for the website but not for the book.
# They go into web/<book>.
#

if [ $# != 1 ]; then
    echo "Usage: makeWebAudio.sh <book dir name>"
    exit 1
fi

dir=`pwd`

booke=$dir/$1
builddir=$dir/web/$1

mkdir -p $builddir

# Make MP3 and OGG files for the input .abc. Since we're listening to
# a doorbell playing the tunes, go for lowest quality (and hence smallest)
# MP3 and OGG. $1 is the input filename, $2 is optional args for timidity.
makeaudiofiles()
{
    name=`basename $1 .abc`

    abc2midi $1 -o $builddir/${name}.mid
    timidity -OwM $2 -o $builddir/${name}.wav $builddir/${name}.mid
    lame -m m -V 9 --quiet $builddir/${name}.wav $builddir/${name}.mp3
    # Timidity can generate OGG directly. But we need to generate WAV
    # for lame, and oggenc produces smaller output. OGG is needed for
    # Firefox's audio tag. FF doesn't support MP3, some others support
    # MP3 but not OGG.
    oggenc -Q -q 0 -o $builddir/${name}.ogg $builddir/${name}.wav

    rm $builddir/${name}.wav
}

# Make audio for a new tempo for the abc file $1, giving the output files
# the same name with a prefix $2. The new tempo is the original tempo
# (120 used if not specified), multiplied by $3 and divided by $4.
# These audio files are for Learner use; I've found that having the
# chords thumping away can make it hard to distinguish the melody, so
# arrange for timidity to mute everything except the melody track.
makeaudiofortempo()
{
    name=`basename $filename .abc`
    newspeedfilename="$2-${name}.abc"

    # Prepare new speed audio files.
    # The tempo is either a plain number, or <notelen>=<number>.
    tempo=`$dir/abcfield.py --field Q $1`
    if [ -z $tempo ]; then
        echo "Warning: $1 has no tempo. Using 120."
        tempo="120"
    fi
    pos=`expr index $tempo '='`
    numtempo=${tempo:pos}
    notelenprefix=${tempo:0:pos}
    # Calculate new tempo.
    newtempo=$(( ( $numtempo * $3 ) / $4 ))
    # Insert new tempo and delete old. Old may not exist,
    # so do this rather than overwrite.
    sed -e "/^Q:/d" -e "/^K:/aQ: ${notelenprefix}${newtempo}" $1 > $builddir/$newspeedfilename
    makeaudiofiles $builddir/$newspeedfilename --mute=0,-1
    rm $builddir/$newspeedfilename
}

# Generate audio files and slow speed (currently half speed) audio files.
find $booke -depth 1 -name "*.abc" | sort |
    while read filename
    do
        makeaudiofiles $filename

        # Now make 1/4, 1/2 and 3/4 speed audio.
        makeaudiofortempo $filename "veryslow" 1 4
        makeaudiofortempo $filename "slow" 2 4
        makeaudiofortempo $filename "littleslow" 3 4
        makeaudiofortempo $filename "normal" 4 4
    done