Mechanical Music Digest  Archives
You Are Not Logged In Login/Get New Account
Please Log In. Accounts are free!
Logged In users are granted additional features including a more current version of the Archives and a simplified process for submitting articles.
Home Archives Calendar Gallery Store Links Info
MMD > Archives > January 2005 > 2005.01.08 > 02Prev  Next


MIDI Explained in Piano Roll Terms
By John Haskey

Hi Robbie, a couple of comments on the recent 050107 MMDigest:


>>[ JPEG compression is intended primarily for continuous tone images,
>>[ whereas GIF encoding is best for line drawings.  GIF means "Graphic
>>[ Interchange Format".  If dimension information must be preserved
>>[ then a newer non-proprietary encoder called PNG (for "Portable
>>[ Network Graphics") gives equal performance.


GIF encoding works well for line drawings because it can only store
information on 256 colors.  Each individual color is stored as a 24-bit
value (8 bits red, 8 bits blue, 8 bits green).  It can also render gray
scale images quite well as well as simple color images.


>>[ You're correct, the MIDI data file contains time information,
>>[ actually stored as measures and beats along with metronome
>>[ information.  The program that plays the MIDI file reads the
>>[ metronome setting and the meter (3/4 or 4/4, etc.) to determine
>>[ how fast to play the music.


In a Standard MIDI File (SMF) the timing information for a given event
is stored as the number of 'ticks' since the last event.  It is up to
the program that reads the file to convert that information to measures
and beats based on parameters in the file header as well as the tempo
map (if it exists).


>>[ The native Cakewalk "WRK" file stores the on-time and the duration
>>[ of the event, whereas standard MIDI files (SMF) store the on-time
>>[ and off-time (or equivalent) as separate events.  The Cakewalk WRK
>>[ file is much larger than a MID file but editing the data is quicker.


Are you sure about this?  I would image that when Cakewalk loads an SMF
it converts it into its internal representation ( on-time + duration)
and then when writing the file converts either to .WRK or .MID as
directed by the user.  .WRK files are larger because they contain much
more 'state' information about the Cakewalk editing session.

Regards,
John Haskey

 [ Maybe I confused Cakewalk with Master Tracks or Performer.  One of
 [ those venerable MIDI file editing programs stores on-time + duration
 [ in its native format.  -- Robbie


(Message sent Sat 8 Jan 2005, 09:10:43 GMT, from time zone GMT-0800.)

Key Words in Subject:  Explained, MIDI, Piano, Roll, Terms

Home    Archives    Calendar    Gallery    Store    Links    Info   


Enter text below to search the MMD Website with Google



CONTACT FORM: Click HERE to write to the editor, or to post a message about Mechanical Musical Instruments to the MMD

Unless otherwise noted, all opinions are those of the individual authors and may not represent those of the editors. Compilation copyright 1995-2024 by Jody Kravitz.

Please read our Republication Policy before copying information from or creating links to this web site.

Click HERE to contact the webmaster regarding problems with the website.

Please support publication of the MMD by donating online

Please Support Publication of the MMD with your Generous Donation

Pay via PayPal

No PayPal account required

                                     
Translate This Page