EIC
mbedでmidi(Format 0)を再生
Diff: midi.cpp
- Revision:
- 0:7c17c3b3a8d7
- Child:
- 1:250e7251f8fc
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/midi.cpp Tue Jul 15 09:45:03 2014 +0000
@@ -0,0 +1,377 @@
+#include "mbed.h"
+#include "midi.h"
+#define STEP 8
+Serial pc(USBTX,USBRX);//tx,rx
+midi::midi(PinName _bzr):bzr(_bzr)
+{
+ //frequency of equal temperament(octave:4)
+ freq[0]=261.626;//C(do)
+ freq[1]=277.183;//C#
+ freq[2]=293.665;//D
+ freq[3]=311.127;//D#
+ freq[4]=329.628;//E
+ freq[5]=349.228;//F
+ freq[6]=369.994;//F#
+ freq[7]=391.995;//G
+ freq[8]=415.305;//G#
+ freq[9]=440.000;//A
+ freq[10]=466.164;//A#
+ freq[11]=493.883;//B
+
+ table=new float[STEP];
+ for(int i=0; i<STEP; i++)table[i]=sin(i/(STEP/8.0)*atan(1.0));
+
+
+
+}
+/*
+midi::~midi(){
+ delete(cache);
+}
+*/
+template<class X>
+void midi::change_endian(X *raw,int byte)
+{
+ X tmp=0;
+ for(int i=0; i<byte; i++)for(int j=0; j<8; j++)tmp+=((*raw&(1<<((byte-i-1)*8+j)))>>((byte-i-1)*8+j))<<(i*8+j);
+ *raw=tmp;
+}
+
+void midi::read(const char *path)
+{
+
+ FILE *mid,*cache;
+ short int pbend;
+ long int dtime,len;
+ int time,ch;
+ float frequency[16];
+ char note,ctrl,value,prgm,prsr;
+ unsigned char tmp2[64];
+ char vel;
+ unsigned char tmp;
+ char prev;
+ time=tmp=prev=tempo=chmax=0;
+
+ if((mid = fopen(path, "rb")) == NULL)goto end1;
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+ fseek(mid, 10, SEEK_SET);
+ fread(&tracks,2,1,mid);
+ //fseek(mid, 2, SEEK_CUR);
+ fread(&crochet,2,1,mid);
+
+ change_endian(&tracks,2);
+ change_endian(&crochet,2);
+
+
+
+
+
+ fseek(mid, 4, SEEK_CUR);
+ fread(&len,4,1,mid);
+ change_endian(&len,4);
+ while(1) {
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&tmp,1,1,mid);
+
+ dtime=0;
+ int i;
+ for(i=0; i<4; i++) {
+ int flag= (tmp&128)==0 ? 1:0;
+
+ if(tmp&128)tmp2[i]=tmp-0x80;
+ else tmp2[i]=tmp;
+ if(flag)break;
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&tmp,1,1,mid);
+ }
+ for(int j=0; j<=i; j++)dtime+=((long int)tmp2[j]<<(7*(i-j)));
+ time+=(int)tempo*((float)dtime/crochet);
+
+
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&tmp,1,1,mid);
+//pc.printf("%d %d\r\n",time,tm.size()*4*1+fq.size()*4*1+ca.size());
+if(tm.size()>640){
+ pc.printf("Memory shortage!\r\n");
+ goto end1;
+
+}
+ if(tmp==0xF0) {
+ len=0;
+ i=0;
+ fread(&tmp,1,1,mid);
+
+ for(i=0; i<4; i++) {
+ int flag= (tmp&128)==0 ? 1:0;
+
+ tmp2[i]=((tmp<<1)>>1);
+ if(flag)break;
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&tmp,1,1,mid);
+
+ }
+
+ for(int j=i; j>=0; j--)len+=((long int)tmp2[j]<<(7*j));
+
+ fseek(mid, len, SEEK_CUR);
+
+ } else if(tmp==0xF7) {
+ len=0;
+ i=0;
+ fread(&tmp,1,1,mid);
+ for(i=0; i<4; i++) {
+ int flag= (tmp&128)==0 ? 1:0;
+ tmp2[i]=((tmp<<1)>>1);
+ if(flag)break;
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&tmp,1,1,mid);
+ }
+ for(int j=i; j>=0; j--)len+=((long int)tmp2[j]<<(7*j));
+ fseek(mid, len, SEEK_CUR);
+ } else if(tmp==0xFF) {
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&tmp,1,1,mid);
+ switch(tmp) {
+ case 0x00:
+ case 0x59:
+ fseek(mid, 3, SEEK_CUR);
+ break;
+
+ case 0x20:
+ case 0x21:
+ fseek(mid, 2, SEEK_CUR);
+ break;
+
+ case 0x54:
+ fseek(mid, 6, SEEK_CUR);
+ break;
+
+ case 0x2F://End of Track
+
+ goto end1;
+ break;
+
+ case 0x51://Tempo
+ fseek(mid, 1, SEEK_CUR);
+ fread(&tempo,3,1,mid);
+ change_endian(&tempo,3);
+ //pc.printf("tempo=%x\r\n",tempo);
+ break;
+
+ case 0x58://Time Signature
+ fseek(mid, 5, SEEK_CUR);
+ break;
+
+ /*case 0x59://Key Signature
+
+ break;
+ */
+ case 0x01:
+ case 0x02:
+ case 0x03:
+ case 0x04:
+ case 0x05:
+ case 0x06:
+ case 0x07:
+ case 0x08:
+ case 0x09:
+ case 0x7F:
+ len=0;
+ i=0;
+ fread(&tmp,1,1,mid);
+
+ for(i=0; i<4; i++) {
+ int flag= (tmp&128)==0 ? 1:0;
+ tmp2[i]=((tmp<<1)>>1);
+ if(flag)break;
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&tmp,1,1,mid);
+
+ }
+
+ for(int j=i; j>=0; j--)len+=((unsigned long int)tmp2[j]<<(7*j));
+
+ fseek(mid, len, SEEK_CUR);
+
+ break;
+
+ default:
+ break;
+ }
+ } else {
+
+
+ //fseek(mid, 1, SEEK_CUR);
+ //fread(&tmp,1,1,mid);
+
+MIDIEVENT:
+ if(0x80<=tmp&&tmp<=0xEF)prev=tmp;
+ if(0x80<=tmp&&tmp<=0x8F) { //note off
+ ch=tmp-0x80;
+ if(chmax<ch)chmax=ch;
+ //fseek(mid, 1, SEEK_CUR);
+ fread(¬e,1,1,mid);
+ fseek(mid, 1, SEEK_CUR);
+
+ tm.push_back(time);
+ //ev.push_back(109);
+ ca.push_back(ch);
+ fq.push_back(0);
+ //vo.push_back(0);
+ } else if(0x90<=tmp&&tmp<=0x9F) { //note on
+ ch=tmp-0x90;
+ //fseek(mid, 1, SEEK_CUR);
+ fread(¬e,1,1,mid);
+ frequency[ch]=freq[note%12]*pow(2.0,(note/12-5.0));
+
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&vel,1,1,mid);
+
+
+ tm.push_back(time);
+ //ev.push_back(109);
+ ca.push_back(ch);
+ fq.push_back(frequency[ch]);
+ //vo.push_back(vel/127.0);
+ }
+
+ else if(0xA0<=tmp&&tmp<=0xAF) { //polyphonic key pressure
+ ch=tmp-0xA0;
+ //fseek(mid, 1, SEEK_CUR);
+ fread(¬e,1,1,mid);
+
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&vel,1,1,mid);
+ } else if(0xB0<=tmp&&tmp<=0xBF) { //control change
+ ch=tmp-0xB0;
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&ctrl,1,1,mid);
+
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&value,1,1,mid);
+ } else if(0xC0<=tmp&&tmp<=0xCF) { //program change
+ ch=tmp-0xC0;
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&prgm,1,1,mid);
+ } else if(0xD0<=tmp&&tmp<=0xDF) { //channel pressure
+ ch=tmp-0x90;
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&prsr,1,1,mid);
+ } else if(0xE0<=tmp&&tmp<=0xEF) { //pitch bend
+ ch=tmp-0xE0;
+ //fseek(mid, 1, SEEK_CUR);
+ fread(&pbend,2,1,mid);
+ } else { //running status
+ tmp=prev;
+ fseek(mid, -1, SEEK_CUR);
+ pc.printf(" ->%x\r\n",tmp);
+ goto MIDIEVENT;
+ }
+ }
+ }
+end1:
+ fclose(mid);
+
+ pc.printf("Loading complete.\r\n");
+}
+
+
+
+
+void midi::play()
+{
+
+ //FILE *fp;
+ AnalogOut buzzer(bzr);
+ int time, /*event, */ch;
+ float *frequency/*,tmp,tmp2,vel[16]*/;
+ //if((fp = fopen(path, "r")) == NULL)goto end;
+ //if(fscanf(fp,"%d\n",&tracks)==EOF)goto end;
+ frequency=new float[chmax+1];
+ for(int i=0; i<=chmax; i++)frequency[i]=0;
+
+/*
+ if(!tm.empty())goto end;
+
+
+ pi=tm.begin();
+ time=*pi;
+ tm.pop_front();
+
+ pi=ev.begin();
+ event=*pi;
+ ev.pop_front();
+
+ pi=ca.begin();
+ ch=*pi;
+ ca.pop_front();
+
+ pd=fq.begin();
+ frequency[ch]=*pd;
+ fq.pop_front();
+
+ pd=vo.begin();
+ vel[ch]=*pd;
+ vo.pop_front();
+*/
+
+ t.reset();
+ t.start();
+ time=0;
+ while(1) {
+//static int count=0;
+//pc.printf("%d\r\n",count++);
+ int now=t.read_us();
+ while(1) {
+ if(time<=now) {
+
+ if(tm.empty())return;
+
+ pi=tm.begin();
+ time=*pi;
+ if(time>=now)break;
+ tm.pop_front();
+/*
+ pi=ev.begin();
+ event=*pi;
+ ev.pop_front();
+*/
+ pch=ca.begin();
+ ch=*pch;
+ ca.pop_front();
+
+
+
+ pf=fq.begin();
+ frequency[ch]=*pf;
+ fq.pop_front();
+ /*
+ pd=vo.begin();
+ vel[ch]=*pd;
+ vo.pop_front();
+ */
+ //pc.printf("%d %d %d %lf %lf\r\n",time,event,ch,frequency[ch],vel[ch]);
+ } else break;
+ }
+ float voltage=0;
+ for(int i=0; i<=chmax; i++)voltage+=/*vel[i]*/(0.5/(chmax+1))*table[(int)(STEP*frequency[i]*now/1000000)%STEP];
+ //for(int i=0;i<tracks;i++)voltage+=(0.5/tracks)*sin(2*pi*frequency[i]*now/1000000);
+ buzzer=0.5+voltage;
+
+ }
+//end:
+ //fclose(fp);
+}
\ No newline at end of file