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Kandinski is my new pre-pre-pre-beta program which generates a picture file from a MIDI file. It does so based on my cycluphonic method of correlating colors to musical pitches. The few careful observers who have seen previous implementations of cycluphonics agree that it gives visual events which seem to sympathize with the generating music, in terms of implied feeling, better than previous "color organ" methods. Kandinski was written with pfe under Linux on a 486. It should be easy to port to another ANSI Forth system, as I am rusty at Forth, and the task at hand didn't call for any trickery, and I avoided the Linux-specific stuff in pfe, mostly because I couldn't find much documentation on it. The code presented here creates a .ppm image file on a selectable track by track basis. The piano envelope option is not implemented yet, just organ. .ppm files can be converted to just about any image format with the unix pbmplus tools, and are viewable in Linux with zgv. The crucial cycluphonic element in Kandinski is the "cycle" construct, a lookup table which Kandinski uses to map a 12 hue color wheel to the Cycle of Fifths. That's the crux of cycluphonics. If you use this code, or cycluphonics, give credit where due.
( kandinski )
( ANSI Forth sourcecode Rick Hohensee begun 199703 )
( A MIDIfile-to-still-picture implementation of my Cycluphonic method
of correlating colors and musical pitches. )
( used i486 Slackware Linux from the InfoMagic LDR sept 96, pfe,
Jeff Glatt's MIDI docs, dpans7 )
( redistribution permission contingent on authorship credit )
( default number base of file is.... ) decimal
( app notes, pfe file-postition is a DOUBLE!
MIDI sizes are SINGLEs
YEESH! "f0" is a variable! AAAAARRRRGGG!!!
hex f0 decimal . doesn't work as wished. )
( my prefered tools, jigs and cheats )
: binary decimal 2 base ! ;
: .base base @ dup decimal . base ! ;
: walk ." " key drop ;
: 0s ( wipe data stack )
depth dup if 0 do drop loop else drop then ;
: paddump ( [ count --- ] counted dump from pad )
pad swap dump ;
( app related ....)
0 value deltasum
2variable trkend 0 0 trkend 2!
0 value dpp ( deltas per pixel )
create rgbs 640 3 * allot
0 value trk#
variable midifile
0 value pbmfile
create organstate 128 allot
organstate 128 0 fill ( pfe allot leaves an "allot" string in the alloted
space )
create 12state 12 allot
12state 12 0 fill
0 value redac
0 value greenac
0 value blueac
0 value backfoot
create cycle 0 , 7 , 2 , 9 , 4 , 11 , 6 , 1 , 8 , 3 , 10 , 5 ,
create wheelred 12 allot
255 c, 255 c, 255 c, 127 c, 0 c, 0 c, 0 c, 0 c, 0 c, 127 c, 255 c, 255 c,
create wheelgreen 12 allot
0 c, 127 c, 255 c, 255 c, 255 c, 255 c, 255 c, 127 c, 0 c, 0 c, 0 c, 0 c,
create wheelblue 12 allot
0 c, 0 c, 0 c, 0 c, 0 c, 127 c, 255 c, 255 c, 255 c, 255 c, 255 c, 127 c,
0 value fid
create ppm
ascii P c, ascii 6 c, 10 c, ascii 6 c, ascii 4 c, ascii 0 c,
bl c, ascii 8 c, ascii 0 c,
bl c, ascii 2 c, ascii 5 c, ascii 5 c,
: msboff 127 and ;
: openin ( opens a file called in.mid in current dir
which can then be referenced via midifile @ )
S" in.mid" r/w bin open-file drop midifile ! ;
: in.mid ( --- fid_of_in.mid ) ( poorly factored, ) midifile @ ;
: inpos ( --- 2inpos ) ( get file position in in.mid )
midifile @ file-position drop ( ior) ;
: inpeek ( [ count --- ] counted read from in.mid to pad )
pad swap
midifile @ read-file drop ;
: trksize ( --- trksize ) ( DOES move inpos )
( build a 32 bit track size cell from the WRONGendian value
, from body0 to body0 )
4 inpeek drop ( endianism translation )
pad c@ 24 lshift
pad 1 + c@ 16 lshift +
pad 2 + c@ 8 lshift +
pad 3 + c@ + ;
2variable prevpos
2variable starttrk 0 0 starttrk 2!
: filebound ( fid --- 0 if inside file )
dup >r file-position drop r> file-size drop 2swap d< ;
: hoptrk ( [ --- inbounds_flag ] body0 to next trk body0 )
trksize 8 + 0 inpos d+ in.mid reposition-file drop
in.mid filebound ;
0 value envelope
0 value noteons 0 value noteoffs
: hinybble 240 and ; ( f0 is a &$^%##%$ variable name! )
hex
0f constant lonybble
binary
: bit7 10000000 and ;
decimal
0 value delta
: bytein pad 1 in.mid read-file drop
1 <> if ( error) cr
." end of in.mid "
quit else pad c@ then ;
: bignum 0
begin bytein dup bit7
while
msboff swap 7 lshift +
repeat
swap 7 lshift + ;
: ignore ( n --- ) ( add n to inpos )
0 inpos d+ in.mid reposition-file drop ;
: ignoreto ( delimiter --- ) ( ignore filebytes to delimiter )
begin dup bytein = until drop ;
0 value moment
: mthd ( --- da position of MThD or fail )
77 ignoreto 84 ignoreto 104 ignoreto 100 ignoreto inpos ;
: mtrk 77 ignoreto 84 ignoreto 114 ignoreto 107 ignoreto inpos ;
: seed
." hit a key please " key
time&date 2drop drop + + + in.mid + ;
: 128to12 ( organstate to 12state, i.e. midinote#s to notename#s )
12state 12 0 fill
128 0 do
organstate i + c@ if
1 i 12 mod 12state + c!
then ( simple for now )
loop
;
: 12torgb 0 to redac 0 to greenac 0 to blueac
12 0 do
12state i + c@ if
i cells cycle + @
cells dup wheelred + @ redac + 2 / to redac
dup wheelgreen + @ greenac + 2 / to greenac
wheelblue + @ blueac + 2 / to blueac
then
loop ;
: orgtorgb ( pixel# --- )
128to12
12torgb
dup redac swap 3 * rgbs + c!
dup greenac swap 3 * 1 + rgbs + c!
blueac swap 3 * 2 + rgbs + c!
;
: reset ( --- ) ( actions on an FF status byte )
bytein case
0 of bignum ignore ." ff 00 ignored " endof
1 of ." text " bignum ignore endof
2 of ." copyright " bignum ignore endof
3 of ." trackname " bignum ignore endof
4 of ." inst name " bignum ignore endof
5 of ." lyric " bignum ignore endof
6 of ." flow marker " bignum ignore endof
7 of ." cue point, sample " bignum ignore endof
33 of 2 ignore ( port # ) endof
47 of ( ." last event of track " ) 1 ignore endof
81 of 4 ignore endof
84 of 6 ignore ." smte o/s ignored " endof
88 of 5 ignore ( time sig ) endof
( ." unknown reset ff thang " )
endcase ;
: sysex ( sysexbyte --- ) ( i.e. message with status hinyb of f )
dup case
240 of 247 ignoreto ." ignoring f0 to f7 " drop endof
241 of ." miditimecode, unsupported " drop endof
242 of ." song position pointer " drop endof
243 of ." song select " drop endof
244 of ." unimplemented f4 sysex " drop endof
245 of ." unimplemented f5 sysex " drop endof
246 of ." tune calibrate " drop endof
249 of ." unimplemented f9 sysex " drop endof
247 of ." discontinue f0/240 stream " drop endof
248 of ." midi clock " drop endof
250 of ." restart song " drop endof
251 of ." midi continue, flow " drop endof
252 of ." stop " drop endof
254 of ." active sense message " drop endof
253 of ." unimplemented fd sysex " drop endof
255 of reset endof
." impossible sysex "
endcase ;
: envelope? cr ." piano envelope or organ? (p=piano/other=organ) " key
ascii p = if -1 to envelope else 0 to envelope then ;
: message ( survey pass )
bytein dup hinybble case
128 of 2 ignore noteoffs 1 + to noteoffs drop endof
144 of noteons 1+ to noteons 2 ignore drop endof
160 of 2 ignore drop endof
176 of 2 ignore drop endof
192 of 2 ignore drop endof
208 of 2 ignore drop endof
224 of 2 ignore drop endof
240 of cr sysex endof
endcase ;
: pianooff ." pianooff " 2 ignore ;
: pianoon 2 ignore ;
: organoff 0 organstate bytein + c! 1 ignore ;
: organon -1 organstate bytein + c! 1 ignore ;
: messageagain ( processing pass )
bytein dup hinybble case
128 of envelope if pianooff else organoff then drop endof
144 of envelope if pianoon else organon then drop endof
160 of 2 ignore drop endof
176 of 2 ignore drop endof
192 of 2 ignore drop endof
208 of 2 ignore drop endof
224 of 2 ignore drop endof
240 of cr sysex endof
endcase ;
: random.kan ( create file[name] kan[random].ppm )
seed srand
ascii k pad c! ascii a pad 1 + c! ascii n pad 2 + c!
8 3 do 26 random 97 + i pad + c! loop
ascii . pad 8 + c! ascii p pad 9 + c! ascii p pad 10 + c!
ascii m pad 11 + c! ;
: makepic
random.kan
pad 12 r/w create-file drop to pbmfile ( new filename exists )
ppm 16 pbmfile write-file drop
80 0 do
rgbs 640 3 * pbmfile write-file drop
loop
;
: process
0 to deltasum 0 to noteons 0 to noteoffs
640 0 do ( i=pixel )
begin
( bignum backfoot )
bignum deltasum + to deltasum
messageagain
i dpp * deltasum >
while
repeat
( paint pixel )
i orgtorgb
loop
makepic
;
: survey ( a track )
inpos starttrk 2!
trksize 0 inpos d+ trkend 2!
0 to deltasum 0 to noteons 0 to noteoffs
begin
bignum deltasum + to deltasum
message
inpos trkend 2@ d<
while
repeat
;
: track survey
noteons if ." This track has notes.... "
cr ." noteons " noteons . ." noteoffs " noteoffs .
." MIDI clocks per pixel " deltasum 640 / dup to dpp .
cr ." wanna do a pic of this track? (y/other) " key ascii y = if
envelope?
starttrk 2@ in.mid reposition-file drop inpos d. walk
noteons . dpp if
process else ." less than one clock per pixel, no can do " walk then
then then
;
: typecheck
mthd
inpos 2dup 4 0 d= if ." apparent std MIDI seq file. Yay. "
else 16 0 d= if ." apparent RMID MIDI file. OK. " else
cr ." in.mid is apparently not a MIDI file " cr
." Copy MIDI file to be processed to in.mid " bye then then ;
: main 0 to trk#
openin typecheck
begin
trk# 1 + dup to trk#
mtrk
track
( bytein does a QUIT on end-of-file )
again
;
Separate documentation file for the Kandinski program Rick Hohensee http://cqi.com/~humbubba or [email protected] please cc to [email protected]