ref: edf23305df765d4a8e35f3ca375566766fa251e4
dir: /src/mus2mid.c/
// Emacs style mode select -*- C++ -*- //----------------------------------------------------------------------------- // // $Id: z_zone.c 434 2006-03-24 19:55:04Z fraggle $ // // Copyright(C) 1993-1996 Id Software, Inc. // Copyright(C) 2005 Simon Howard // Copyright(C) 2006 Ben Ryves 2006 // // This program is free software; you can redistribute it and/or // modify it under the terms of the GNU General Public License // as published by the Free Software Foundation; either version 2 // of the License, or (at your option) any later version. // // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // // You should have received a copy of the GNU General Public License // along with this program; if not, write to the Free Software // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA // 02111-1307, USA. // // mus2mid.c - Ben Ryves 2006 - http://benryves.com - [email protected] // Use to convert a MUS file into a single track, type 0 MIDI file. #include <stdio.h> #include "memio.h" #include "mus2mid.h" // MUS event codes typedef enum { mus_releasekey = 0x00, mus_presskey = 0x10, mus_pitchwheel = 0x20, mus_systemevent = 0x30, mus_changecontroller = 0x40, mus_scoreend = 0x60 } musevent; // MIDI event codes typedef enum { midi_releasekey = 0x80, midi_presskey = 0x90, midi_aftertouchkey = 0xA0, midi_changecontroller = 0xB0, midi_changepatch = 0xC0, midi_aftertouchchannel = 0xD0, midi_pitchwheel = 0xE0 } midievent; // Structure to hold MUS file header typedef struct { unsigned char id[4]; unsigned short scorelength; unsigned short scorestart; unsigned short primarychannels; unsigned short secondarychannels; unsigned short instrumentcount; } musheader; // Standard MIDI type 0 header + track header static unsigned char midiheader[] = { 'M', 'T', 'h', 'd', // Main header 0x00, 0x00, 0x00, 0x06, // Header size 0x00, 0x00, // MIDI type (0) 0x00, 0x01, // Number of tracks 0x00, 0x46, // Resolution 'M', 'T', 'r', 'k', // Start of track 0x00, 0x00, 0x00, 0x00 // Placeholder for track length }; // Cached channel velocities static unsigned char channelvelocities[] = { 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, 127 }; // Timestamps between sequences of MUS events static unsigned int queuedtime = 0; // Counter for the length of the track static unsigned int tracksize = 0; static unsigned char mus2midi_translation[] = { 0x00, 0x20, 0x01, 0x07, 0x0A, 0x0B, 0x5B, 0x5D, 0x40, 0x43, 0x78, 0x7B, 0x7E, 0x7F, 0x79 }; // Write timestamp to a MIDI file. static int midi_writetime(unsigned int time, MEMFILE *midioutput) { unsigned int buffer = time & 0x7F; unsigned char writeval; while ((time >>= 7) != 0) { buffer <<= 8; buffer |= ((time & 0x7F) | 0x80); } for (;;) { writeval = (unsigned char)(buffer & 0xFF); if (mem_fwrite(&writeval, 1, 1, midioutput) != 1) { return 1; } ++tracksize; if ((buffer & 0x80) != 0) { buffer >>= 8; } else { queuedtime = 0; return 0; } } } // Write the end of track marker static int midi_writeendtrack(MEMFILE *midioutput) { unsigned char endtrack[] = {0xFF, 0x2F, 0x00}; if (midi_writetime(queuedtime, midioutput)) { return 1; } if (mem_fwrite(endtrack, 1, 3, midioutput) != 3) { return 1; } tracksize += 3; return 0; } // Write a key press event static int midi_writepresskey(unsigned char channel, unsigned char key, unsigned char velocity, MEMFILE *midioutput) { unsigned char working = midi_presskey | channel; if (midi_writetime(queuedtime, midioutput)) { return 1; } if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } working = key & 0x7F; if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } working = velocity & 0x7F; if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } tracksize += 3; return 0; } // Write a key release event static int midi_writereleasekey(unsigned char channel, unsigned char key, MEMFILE *midioutput) { unsigned char working = midi_releasekey | channel; if (midi_writetime(queuedtime, midioutput)) { return 1; } if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } working = key & 0x7F; if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } working = 0; if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } tracksize += 3; return 0; } // Write a pitch wheel/bend event static int midi_writepitchwheel(unsigned char channel, short wheel, MEMFILE *midioutput) { unsigned char working = midi_pitchwheel | channel; if (midi_writetime(queuedtime, midioutput)) { return 1; } if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } working = wheel & 0x7F; if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } working = (wheel >> 7) & 0x7F; if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } tracksize += 3; return 0; } // Write a patch change event static int midi_writechangepatch(unsigned char channel, unsigned char patch, MEMFILE *midioutput) { unsigned char working = midi_changepatch | channel; if (midi_writetime(queuedtime, midioutput)) { return 1; } if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } working = patch & 0x7F; if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } tracksize += 2; return 0; } // Write a valued controller change event static int midi_writechangecontroller_valued(unsigned char channel, unsigned char control, unsigned char value, MEMFILE *midioutput) { unsigned char working = midi_changecontroller | channel; if (midi_writetime(queuedtime, midioutput)) { return 1; } if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } working = control & 0x7F; if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } // Quirk in vanilla DOOM? MUS controller values should be // 7-bit, not 8-bit. working = value;// & 0x7F; // Fix on said quirk to stop MIDI players from complaining that // the value is out of range: if (working & 0x80) { working = 0x7F; } if (mem_fwrite(&working, 1, 1, midioutput) != 1) { return 1; } tracksize += 3; return 0; } // Write a valueless controller change event static int midi_writechangecontroller_valueless(unsigned char channel, unsigned char control, MEMFILE *midioutput) { return midi_writechangecontroller_valued(channel, control, 0, midioutput); } // Read a MUS file from a stream (musinput) and output a MIDI file to // a stream (midioutput). // // Returns 0 on success or 1 on failure. int mus2mid(MEMFILE *musinput, MEMFILE *midioutput) { // Header for the MUS file musheader musfileheader; // Descriptor for the current MUS event unsigned char eventdescriptor; int channel; // Channel number musevent event; // Bunch of vars read from MUS lump unsigned char key; unsigned char controllernumber; unsigned char controllervalue; // Buffer used for MIDI track size record unsigned char tracksizebuffer[4]; // Flag for when the score end marker is hit. int hitscoreend = 0; // Temp working byte unsigned char working; // Used in building up time delays unsigned int timedelay; int i; // Grab the header if (mem_fread(&musfileheader, sizeof(musheader), 1, musinput) != 1) { return 1; } #ifdef CHECK_MUS_HEADER // Check MUS header if (musfileheader.id[0] != 'M' || musfileheader.id[1] != 'U' || musfileheader.id[2] != 'S' || musfileheader.id[3] != 0x1A) { return 1; } #endif // Seek to where the data is held if (mem_fseek(musinput, (long)musfileheader.scorestart, SEEK_SET) != 0) { return 1; } // So, we can assume the MUS file is faintly legit. Let's start // writing MIDI data... mem_fwrite(midiheader, 1, 22, midioutput); // Now, process the MUS file: while (!hitscoreend) { // Handle a block of events: while (!hitscoreend) { // Fetch channel number and event code: if (mem_fread(&eventdescriptor, 1, 1, musinput) != 1) { return 1; } channel = eventdescriptor & 0x0F; event = eventdescriptor & 0x70; // Swap channels 15 and 9. // MIDI channel 9 = percussion. // MUS channel 15 = percussion. if (channel == 15) { channel = 9; } else if (channel == 9) { channel = 15; } switch (event) { case mus_releasekey: if (mem_fread(&key, 1, 1, musinput) != 1) { return 1; } if (midi_writereleasekey(channel, key, midioutput)) { return 1; } break; case mus_presskey: if (mem_fread(&key, 1, 1, musinput) != 1) { return 1; } if (key & 0x80) { if (mem_fread(&channelvelocities[channel], 1, 1, musinput) != 1) { return 1; } channelvelocities[channel] &= 0x7F; } if (midi_writepresskey(channel, key, channelvelocities[channel], midioutput)) { return 1; } break; case mus_pitchwheel: if (mem_fread(&key, 1, 1, musinput) != 1) { break; } if (midi_writepitchwheel(channel, (short)(key * 64), midioutput)) { return 1; } break; case mus_systemevent: if (mem_fread(&controllernumber, 1, 1, musinput) != 1) { return 1; } if (controllernumber < 10 || controllernumber > 14) { return 1; } if (midi_writechangecontroller_valueless(channel, mus2midi_translation[controllernumber], midioutput)) { return 1; } break; case mus_changecontroller: if (mem_fread(&controllernumber, 1, 1, musinput) != 1) { return 1; } if (mem_fread(&controllervalue, 1, 1, musinput) != 1) { return 1; } if (controllernumber == 0) { if (midi_writechangepatch(channel, controllervalue, midioutput)) { return 1; } } else { if (controllernumber < 1 || controllernumber > 9) { return 1; } if (midi_writechangecontroller_valued(channel, mus2midi_translation[controllernumber], controllervalue, midioutput)) { return 1; } } break; case mus_scoreend: hitscoreend = 1; break; default: return 1; break; } if (eventdescriptor & 0x80) { break; } } // Now we need to read the time code: if (!hitscoreend) { timedelay = 0; for (;;) { if (mem_fread(&working, 1, 1, musinput) != 1) { return 1; } timedelay = timedelay * 128 + (working & 0x7F); if ((working & 0x80) == 0) { break; } } queuedtime += timedelay; } } // End of track if (midi_writeendtrack(midioutput)) { return 1; } // Write the track size into the stream if (mem_fseek(midioutput, 18, SEEK_SET)) { return 1; } for (i = 0; i < 4; ++i) { tracksizebuffer[i] = (unsigned char)(tracksize >> 24); tracksize <<= 8; } if (mem_fwrite(tracksizebuffer, 1, 4, midioutput) != 4) { return 1; } return 0; }