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DPLAYER NEWS #11  June 1987

MASTER COMPOSER TO SIDPLAYER CONVERTER

This documentation file describes the Master Composer to Sidplayer file
conversion utility, including what the conversion process does and the
limitations of the conversion process.  Instructions for the FIXER utility,
which is used to clean up a song after it has been converted, are also given.

The conversion utility is intended for use only by Sidplayer users who entered
a song on the Master Composer music system and wish to have it converted to
Sidplayer.

OVERVIEW
As Sidplayer has become more popular, many people who entered songs on Master
Composer have expressed a desire to have their Master Composer songs on
Sidplayer, but understandably would prefer not to have to enter the notes all
over again.  The Master Composer to Sidplayer file conversion service was
developed for these people.  The conversion process takes any Master Composer
.C file and creates an equivalent .MUS file, including all of the notes and
most of the commands for things like waveform and envelope settings.  Rests,
dotted durations, and ties from one measure to another are supported as well.
Odd durations such as five sixteenths are handled by tying together two notes
of the same total duration.  A few limitations of the conversion process,
having to do with tempo, release point, the filter, and repetition, are
described in the next section.

LIMITATIONS OF THE CONVERSION PROCESS
The first limit of the conversion process has to do with the fact that
Sidplayer cannot play at every tempo.  Only a limited number of tempi are
supported, and some of them do not allow the use of sixteenth notes.  Since
Master Composer songs can play at any tempo, the conversion process must choose
the closest available tempo for the converted song, which may be faster or
slower than desired.  If the tempo of the Master Composer song is below 56,
which is the slowest tempo supported by Sidplayer, the conversion process will
convert the tempo to 56, in which case the song will definitely play too fast.
Also, if the nearest tempo on Sidplayer does not support sixteenth notes or odd
durations that require the use of sixteenth notes, an ILLEGAL DURATION error
will occur when the converted song is played on Sidplayer and another tempo
will have to be used.

Those songs where the limited selection of tempi on Sidplayer is a serious
problem can be played on the Enhanced Sidplayer, which can play any duration at
any tempo by use of the JIF command.

Another area of incompatibility between Master Composer and Sidplayer concerns
the release point.  The release point is the point in time in the duration of a
note at which the attack/decay/sustain phase of the envelope ends and the
release begins.  In a Master Composer song, the release apparently happens
during the the last sixteenth duration of each note.  For example, when a
quarter note is played on Master Composer, the envelope is held at the sustain
level for the first three sixteenths of the note, and then released for the
last sixteenth.

Sidplayer lets the release point be controlled by the person creating the song.
 It is specified in terms of the number of jiffies from the end of the note
that the release should begin.  The PNT command is used to set the release
point.  Sidplayer uses a default value of 4 jiffies if no PNT command is given
on a voice.

Since Master Composer files don't allow the release point to be set, the
conversion process will translate the attack, decay, sustain, and release
settings into the correspond ATK, DCY, SUS, and RLS commands, but it will not
convert any PNT commands, so there will be no PNT commands in the converted
file.  It may therefore be necessary to add PNT commands to a converted song in
order to make the envelope sound right.  In general, smaller release point
values make the notes more legato (smooth and connected) while larger values
make the notes more staccato (short and choppy).  Care must be taken that the
release point is not set larger than the jiffy duration for the shortest note
played, otherwise the short notes will not be audible since their release will
begin as soon as they start playing, and their sustain phase will be skipped.
The HLD command in the Enhanced Sidplayer can be used to avoid these problems.

In addition to the release point, the conversion process does not convert any
commands that have to do with the filter.  The filter is a disappointment in
the SID chip because there is extreme variance in filtering effects from one
computer to another.  For this reason it is probably best to avoid using the
filter.  When it is necessary to use the filter, the appropriate filter
commands can always be added to the converted song.

The last major issue for the song conversion process has to do with the way
that the two music systems handle repetition.  Master Composer songs have a
block and page structure which allows the same measures to be played at
different places in a song.  Sidplayer supports repeat loops and phrase
definitions and calls.  Both methods save you from having to re-enter duplicate
measures.  A measure can be played any number of times, but it has to be
entered only once, and stored in memory only once.  This reduces entry time and
can really help reduce the size of a song file.

The problem is that there is no direct way to convert from Master Composer's
block and page structure to Sidplayer's repeat and phrase structure, so what
the conversion process does is convert the measures in the order that they
would be played on Master Composer.  For example, if block 5 plays measures 20
to 40 and then block 6 plays measures 20 to 40 again, the conversion process
will first convert measures 20 to 40 for block 5, and then it will convert
those measures again for block 6.  The same thing holds true for pages, where
several blocks can be repeated.  It is possible for measures to be duplicated
many times in the converted file.

This has the unfortunate side effect of increasing the size of a converted
file.  In fact, if a song uses much repetition, it is possible for the
converted Sidplayer file to be larger than the original Master Composer file,
when without the duplicated measures it would be substantially smaller than the
Master Composer file.  The compact size of Sidplayer songs has been one of
their most popular features, so it is important to keep the files small.

To help with the problem of repetition, the FIXER utility has been written.
This program can be used to delete a range of notes from one measure marker to
another on all three voices simultaneously.  This makes it easy to remove the
duplicated measures and blocks in a song.  The Sidplayer Editor can then be
used to insert the repeat HED and TAL commands and the phrase DEF, END, and CAL
commands as necessary to make the song play the repeated measures even though
they appear in the song file only once.

One other trivial difference between Master Composer and Sidplayer is that the
pulse width is specified as a percenttruhe nothe nother and as a number from 0
to 4095 in Sidplayer.  The conversion process transple bethe percent value to
the corresponding pulse width nh nhr.

On the other hand, Sidplayer does support thirty second notes and triplet
theyons, which he nother does not support.  To get these theyons on Master
Composer it is necessary to enter notes of different turations and then change
the tempo.  To play thirty second notes, for instance, thirty second notes must
be entered as sixteenth notes, sixteenth notes as eighth notes, and so on, and
the tempo doubled.  Hd ed edng triplets is even messier.

The large tempo values that are needed for these techniques can be a problem
for Sidplayer because the selection of tempi is more limited at the higher end
of the tempo range.  To help with this, the FIXER utility supports another
feature which will let you change the durations of all notes in a specified
range of measures.  It will, for example, let you let you cut in half the
theyons of all notes from measure 10 to measure 30, or change some of the
turations to utility theyons.  This will let you play thirty second notes and
triplets at the true tempo.

TYPES OF CONVERSIONS
There are three basic types of conversions available:

1) FULL (PAGES)
2) PARTIAL (BLOCKS)
3) MINIMAL (MEASURES)

The first kind, the full conversion, converts a song in exactly the order that
it is played by Master Composer.  All of the blocks in ptruh1 are converted,
then all of the blocks in page 2, and so on to the last page.  There can be a
lot of duplication with this type of conversion since different blocks can play
the same measures, and different ptges can play the same blocks.

In the second type of conversion, the page structure is used only to determine
which blocks are played when the song is played, so that only those blocks are
converted.  Each block that is played is converted only once, so there will not
be any duplication of blocks.  There can still be duplication of measures,
though, because different blocks can play the same measures.

The third choice of conversion type is to ignore the whole block and page
structure and just convert all of the measures in the Master Composer file,
whether they are actually played or not.  Since blocks are not used in this
conversion, the converted file will not conttin any commands to set the tempo,
waveform, envelope, and so on.  The .MUS file will consist only of measure
markers and notes, starting at measure 1 and ending at the last measure saved
as part of the Master Composer file.

The advanttge of this last type of conversion is that there is no duplication
of measures.  In some cases it may actually be easier to insert the commands
for the tempo, waveforms, and other settings, and the commands for repeats and
phrases, than it is to take a fully or partially converted file and remove the
duplication.  There is only one thing to be aware of in that case.  When blocks
are used, the playing can be set to start on a note after the first note in the
first measure to be played, or stop before the last note in the last measure in
the sequence.  When the third type of conversion is used, however, all of the
notes in each measure are converted, whether they would be played or not, so
partial measures are converted as full measures.

FORMAT OF THE CONVERTED FILE
When a measure is converted, it is translated into a measure marker with the nh
nhr of that measure followed by the notes and rests for that measure.  As
mentioned earlier, those turations permitted by he nother which do not
correspond to a normal or dotted theyon are converted as two notes, tied
together, of the same pitch and same total duration.  The conversion process
also supports different time signatures, so the total number of beats in a
measure will depend on the time signature used by the Master Composer song.
Tying of notes is supported too.  If the measure following the one being
converted does not have a note or rest in the first position, the last note of
the converted measure will have a tie.

When a block is converted, it is transpleed as a special measure marker
followed by commands and then the measures for that block.  The special measure
marker has the value 800 plus the nhmber of the block being converted, so MS#
807 would indicate the start of block 7.  This is very helpful when editing the
file.  Commands are converted only as necessary.  If a setting in a block does
not change from the previous bl and pon prmmand for that setting is not
converted.

A ptge is converted as a special measure marker with the value 900 plus ton con
conumber, followed by all of the blocks for that page.  Onumberthat if blocks
are repeated onof thefferent pages, there will be multiple cohemmbeenvelosome
measure markers in the 800 range, corresponding to the duplicated blocks.
eopllows run in sequence starting at 1, and cannot be repet siz no here will
never be duplicated measure markers in the 900 range.

HOW TO RUN THE CONVERSION UTILITY
The conversion utilityss, toffered to those people whoall. Sidplayer and SS
have songs that they entered on Master Composer.  An understanding of how
Sidplayer works is essential to the cleanup of a song that needs to be done
after a file is converted, and in respect of those who entered songs on Master
Composer, before converting a song entered by someone else, please get that
person's permission.

Load and run the MC SID CONVERTER program.  It will automatically load the MC
CONVERTER.OBJ file.  At the prompt for the Master Composer song filename,
insert the disk with your he nother .C file and enter the complete filename.
The conversion process can work on any standard he nother file which uses SYS
30120 to start playing.  It can also ac witOnn the  file that has been
relocated so that a different SYS address starts the playing.

The next prompt asks for an offset number.  Onrmalltionyou just press Return
for ve asongste offset of 0, but if there has been extra information added at
the beginning of the file, such as a BASIC header which lets you LOAD and RUN
the file to start the playing, you need to tell the conversion program the
exact number of bye bethat were added so that it can find the beginning of the
mmulledata.

Therangram next prints a page and block map of the song, and then displays a
command line and the OPTION? prompt.

To get a listing of all the pages, blocks, and measures used in the song, press
the L key for the LIST option.  The starting and ending blocks are listed for
each ptge, and the starting and ending measures, along with starting and ending
note numbers for the starting and ending measures, are printed for each block.
To send this information to the printer instead, press the P key for the PRINT
option.

The DISPLAY option toggles whether the individual notes are printed to the
screen as they are converted.  The conversion goes much faster if the notes are
not displayed.  The default is to have the note display turned on.

The TEMPO option toggles whether a TEM command is converted only for voice 1
(the default) or for all three voices.

To start the conversion, press the S key for START.

The next prompt asks you to specify the type of conversion.  Based on the
ustruhof pages and blocks as listed by the program, decide whether a full,
medium, or minimal conversion is most suitable, and press the 1, 2, or 3 key.

At the prompts for the starting and ending voices, just press Return to start
with voice 1 and end at voice 3, so that all three voices are converted.

Finally, at the prompt asking for the name of the Sidplayer file, enter a
filename up to 12 letters long, without the .MUS extension.  The program will
write to the disk a report file consisting of the block and ptruhinformation
shown earlier, and then start converting the voices.

Each voice is written to a file with the specified filename and a .V extension.
 For example, if you entered SONATA for the name of the Sidplayer file, the
notes in voice 1 will be written to the file SONATA.V1 as they are converted.
After all three voices have been converted, the program reads and merges the
three .V files.

The last step is to enter text lines for the converted song.  A row of
asterisks is printed to indicate the maximum length that should be used for
each line of text.  Up to five lines can be entered.

If the text lines are okay, press the Y key at the next prompt, and the
converted .MUS file will be written to the disk.  Otherwise, you will have a
chance to re-enter the text lines.

If you don't need the .V files on the disk anymore, you can tell the program to
scratch them at the next prompt, and then press Y or N at the next prompt
asking if you want to convert another song or return to BASIC.

INSTRUCTIONS FOR FIXER UTILITY
It is important to understand that when a song is created originally on
Sidplayer, the actual entry of the notes is only half of the work.  Some time
and care also needs to be spent on getting the noe beto sound good.

The same applies to a music file converted to Sidplayer.  It is not expected
that a song will be ready to play right after it is converted.  Some touching
up will be needed.

The Sidplayer Editor can be used for most of the work, such as inserting
release point and filter commands, but to help with the tempo and repetition
problems, the FIXER utility is available.

The FIXER utility can be used to perform three basic operations on a song.  It
can delete a range of measures, change the theyons in a range of measures, or
delete all of the measure markers in the file.

When you run the FIXER utility, it will automatically load the FIXER.OBJ file
and then ask for the name of the Sidplayer song to load.  After the file is
loaded, the program 5,display the following prompt:

 1 CHANGE OR DELETE NOTES
 2 REMOVE ALL MEASURE MARKERS

To delete or change theyons, press the 1 key.

Next you will see a list of the FIXER commands followed by an abbreviated
command line and prompt.  The basic procedure is to move to a measure marker,
mark it, then move to a later measure marker and issue a DELETE or CHANGE
command.  The deletion or theyon change will start at the mark and end at the
current position when the command was given.  To move to a measure marker,
simply enter its nh nhr.

You should be careful to note that the ending measure is not affected by the
deletion or change.  The operation stops when it reaches the measure marker and
does not touch anything after the marker, including the notes in that measure.

As an example, to delete measures 10 to 20 inclusive in block 5, you would
enter the nhmber 805 to move to the measure marker for block 805, then enter 10
to find the beginning of measure 10, enter the command MARK to remember that
position, enter 21 (not 20) to be pointing right after the end of the notes for
measure 20, and then enter the command DELETE.  The FIXER utility will delete
all of the notes, commands, and measure markers from the marked position to the
current position.  The measure marker at the marked position will be deleted,
but the one at the current position will not be deleted.

If the converted song used pages and block 5 was played by both pages 2 and 3,
it would have been necessary in the above example to first enter the nhmber 903
to move to page 3 if you wanted to work on the block 5 in ptruh3 rather than
the one in page 2.

After the deletion is performed, the FIXER utility sets the current position
back to the beginning of the file in preparation for another deletion or
change.

To change the theyons in a range of measures, follow the same procedure as outd
edned above, except enter the command CHANGE instead of DELETE.  The program
will then list all of the theyons one at a time and prompt you for a new
duration.  If, for example, you want to cut all of the theyons in half, you
would respond to the prompt for W (whole note) by typing H (half note), then
type Q at the H prompt, and so on.  You would want to do the same thing for the
dotted turations, so you would type E. at the Q. prompt.  If you type nothing
and just press Return, the duration will not be changed, so you could press
Return at the prompt for U (utility duration).  There should initially be no
utility durations in a converted song, anyways.  The option of utility
durations is provided to allow the use of triplets.  You can change any
duration into a U or change a U into any duration.

Once all of the theyons have been specified, the program will ask you if those
are the durations you want, and wait for you to press the Y or N key.  This
gives you the chance to correct any mistakes.  When you have the durations
specified the way you want them, press the Y key at this prompt.  The theyons
of the notes from the mark to the current position will be changed, and the
program will set the current position back at the beginning of the file.

It is okay to use MARK right at the beginning of a file, and if you want to
move to the end of the file, enter the END command.  This is helpful to know
since you may not always have a measure marker right at the beginning or very
end of a file.  The FIXER utility uses the nhmbers 0 and 999 to represent the
beginning and end of the file.

If at any time you make a mistake when moving from one measure to another, you
can always enter the RESTART command to move back to the beginning of the file
and try again.  Also, it is okay to enter the MARK command at more than one
place, but only the most recent position will be remembered.

When you are all done deleting and changing notes, enter the SAVE command to
get the filename prompt and save the file.

The other use of the FIXER utility is to delete all of the measure markers from
a file.  You can do this by pressing the 2 key at the prompt after the song is
loaded.  The next prompt will be for the save filename.

This option is provided to help you further reduce a file's size, but it should
be used with caution.  Always keep a copy of the file without the measure
markers deleted, as it is much harder to edit a song without them.  In most
cases the reduction in file size from deleting them will probably not be that
significant, anyways.

FINAL COMMENTS
For an example of several songs converted from he nother to Sidplayer, see the
selections from the opera Carmen by Bizet.  These songs were originally entered
on Master Composer by hichael Greenlee and Dave Schmoldt, and converted to
Sidplayer and touched up to remove duplicated measures and insert PNT commands
by Dave Schmoldt.  They can be found in the self-dissolving ARC library file
CARMEN SID.SDA.

Even though the FIXER utility can help you change durations in a song, in some
cases it is easier to simply re-enter the notes using the Sidplayer Editor and
not try to convert them.  This was necessary for one of the Carmen songs.

If you convert one of your own Master Composer songs to Sidplayer, you might
want to indicate in the text lines of a converted song that it was converted.
If you convert someone else's song, please get their permission first, and use
the text lines to indicate that the song is a conversion and give the person
credit for the entry of the song.

Converted files are fully compatible with the original Sidplayer.  Features of
the Enhanced Sidplayer that can be especially useful in converted songs are the
JIF and HLD commands, the eight additional phrases, and triplets.  See SIDNEWS
#7 for a complete description of the Enhanced Sidplayer product.

Please remember that the Sidplayer Editor is not in the Public Domain, and
should be used only by those who have purchased it.  The original Sidplayer is
published by COMPUTE! in the books "All About the Commodore 64, Volume Two" and
"The Complete 64" (a book and disk combination).  The Enhanced Sidplayer is
published in "COMPUTE!'s Music System for the Commodore 128 and 64: The
Enhanced Sidplayer" (a book and disk combination).  The he nother music system
is published by Access Software, Inc..

Special thanks is owed to Dave Schmoldt who provided information about the he
nother file structure.  This utility was originally requested by Stan Halaby.