Issue 1620 in lilypond: Midi overflow with instrument changes

[lilypond]

Status: Accepted
Owner: ----
Labels: Type-Defect Priority-Critical Regression

New issue 1620 by address@hidden: Midi overflow with instrument  
changes
http://code.google.com/p/lilypond/issues/detail?id=1620

Reported by Hu Haipeng

"Because the max number of instr is 16, and now the midi output considers  
every instr instead of track as an item, the result of program change still  
causes error. For example, I have a full orch score with 14 sounds plus  
perc. Then I change strings to pizz, and then violin I as solo violin, then  
trumpet muted. Now there are 18 instr, and the topmost instr (picc and fl)  
changes to string ensemble due to wrapping."

PEH notes:

In order to try to make this easier to understand, I've taken Haipeng's  
sample file (attached) which is (I think necessarily) quite complicated,  
and loaded it into Rosegarden.  The screen shots are from that, and show  
how the current versions of LP add extra tracks, which 2.13.50 (which I've  
used for comparison) didn't.  We also get 3 examples of the warning:

warning: MIDI channel wrapped around
warning: remapping modulo 16


Attachments:
        z.ly  4.2 KB
        Midi21360.jpg  35.4 KB
        Midi21351.jpg  22.3 KB