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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.

How Kandinski operates ( I hope )

( 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 rickh@capaccess.org please cc to humbubba@cqi.com