RMI与MIDI文件相互转换程序。

rmitomid.c

//参考：http://www.yueshou.net/jiao/shuma/yingjian/200608/14735.html
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#define stricmp _stricmp
struct RMIDHeader
{
	char strRIFF[4];
	int chunkSize;
	char strFormat[4];
	char strdata[4];
	int midiFileChunkSize;
};
size_t WriteToFile(const char *fn, const char *pdata, int length)
{
	FILE *pfileOut;
	fopen_s(&pfileOut, fn, "wb");
	size_t wrotebytes = 0;
	if (pfileOut)
	{
		const int tbuffersize = 64;
		size_t writebytes;
		for (int i = 0; i < length; i += tbuffersize)
		{
			writebytes = min(tbuffersize, length - i);
			wrotebytes += fwrite(pdata + i, writebytes, 1, pfileOut)*writebytes;
		}
		fclose(pfileOut);
		printf("写入了%zd字节至 %s。\n", wrotebytes, fn);
	}
	else printf("无法写入文件至 %s。\n", fn);
	return wrotebytes;
}
int ConvertToMIDI(FILE *pfileIn, const char *fn)
{
	struct RMIDHeader rh;
	fread(&rh, sizeof rh, 1, pfileIn);
	if (strncmp(rh.strRIFF, "RIFF", 4))printf("文件头不正确：%s\n", rh.strRIFF);
	if (strncmp(rh.strFormat, "RMID", 4))printf("格式标签不正确：%s\n", rh.strFormat);
	if (strncmp(rh.strdata, "data", 4))printf("data标签不正确：%s\n", rh.strdata);
	printf("RIFF文件内容区段大小：%d字节\nMIDI文件大小：%d字节\n", rh.chunkSize, rh.midiFileChunkSize);

	strcpy_s(strrchr(fn, '.'), 5, ".mid");
	char *pbuffer = (char*)malloc(rh.midiFileChunkSize);
	fseek(pfileIn, sizeof rh, SEEK_SET);
	fread(pbuffer, rh.midiFileChunkSize, 1, pfileIn);
	if (!WriteToFile(fn, pbuffer, rh.midiFileChunkSize))return -1;
	free(pbuffer);
	return 0;
}
int ConvertToRMI(FILE *pfileIn, const char *fn)
{
	struct RMIDHeader rh = { "RIFF",sizeof rh - 8,"RMID","data",0 };
	fseek(pfileIn, 0, SEEK_END);
	rh.midiFileChunkSize = ftell(pfileIn);
	fseek(pfileIn, 0, SEEK_SET);
	rh.chunkSize += rh.midiFileChunkSize;

	strcpy_s(strrchr(fn, '.'), 5, ".rmi");
	int filesize = rh.midiFileChunkSize + sizeof rh;
	char *pbuffer = (char*)malloc(filesize);
	memcpy(pbuffer, &rh, sizeof rh);
	fread(pbuffer + sizeof rh, rh.midiFileChunkSize, 1, pfileIn);
	if (!WriteToFile(fn, pbuffer, filesize))return -1;
	free(pbuffer);
	return 0;
}
int main(int argc, char *argv[])
{
	FILE *pfileIn;
	char rstrfile[_MAX_PATH], *strfile = rstrfile;
	if (argc != 2)
	{
		puts("请指定要转换的文件：");
		gets_s(strfile, _MAX_PATH);
		if (strfile[0] == '\0')
		{
			puts("没有选择文件。");
			return 1;
		}
	}
	else
		strcpy_s(strfile, _MAX_PATH, argv[1]);
	if (strfile[0] == '\"')
	{
		strfile++;
		strfile[strlen(strfile) - 1] = '\0';
	}
	fopen_s(&pfileIn, strfile, "rb");
	if (!pfileIn)
	{
		puts("文件打开失败……");
		return -1;
	}
	if (stricmp(strrchr(strfile, '.'), ".rmi") == 0)
		ConvertToMIDI(pfileIn, strfile);
	else if (stricmp(strrchr(strfile, '.'), ".mid") == 0)
		ConvertToRMI(pfileIn, strfile);
	else puts("不支持的格式。");
	fclose(pfileIn);
	return 0;
}