winamp/Src/Plugins/Input/in_midi/gmf.cpp

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2024-09-24 13:54:57 +01:00
#include "main.h"
#include "cvt.h"
bool is_gmf(const BYTE* p,size_t s)
{
return s>0x20 && *(DWORD*)p==_rv('GMF\x01');
}
bool load_gmf(MIDI_file * mf,const BYTE* buf,size_t siz)
{
grow_buf wb;
wb.write_dword(_rv('MThd'));
wb.write_dword(_rv(6));
MIDIHEADER h={0x000,0x100,0xC000};
wb.write(&h,6);
wb.write_dword(_rv('MTrk'));
int tempo=100000*rev16(*(WORD*)(buf+4));
wb.write_dword(rev32(siz-9+8+3));//MTrk size
BYTE tempo_event[8]={0,0xFF,0x51,0x03,(BYTE)((tempo>>16)&0xFF),(BYTE)((tempo>>8)&0xFF),(BYTE)(tempo&0xFF),0};
wb.write(tempo_event,8);
wb.write(buf+8,siz-9);
wb.write("\xFF\x2F\x00",3);
mf->size = wb.get_size();
mf->data = (BYTE*)wb.finish();
return !!mf->data;
}