#include <stdio.h>
	short bfType; // ID:"BM" 
struct FILEHEADER{
	unsigned int bfSize; //GRANDEZZA DEL FILE(BYTE)
	short int    bfReserved1;
	short int    bfReserved2; 
	unsigned int bfOffBits; //TOTALE DEI INFORMAZIONI(BYTE) 
	                        //DISOLITO 54BYTE COME IN NOSTRO CASO
} fileHeader;

struct INFOHEADER{ 
	unsigned int      biSize;//OCCUPA 4BYTE
	int        biWidth; //LARGHEZZA
	int        biHeight; //ALTEZZA
	short int       biPlanes; 
	short int       biBitCount;//QUALITA' DELL'IMMAGINE 8,16,24,32 BIT
	unsigned int      biCompression;//MODALITA' DI COMPRESSIONE 
	unsigned int      biSizeImage; // TOTALE DEI PIXEL
	int        biXPelsPerMeter; 
	int        biYPelsPerMeter; 
	unsigned int      biClrUsed;//COLORI UTILIZZATI
	unsigned int      biClrImportant;//COLORI IMPORTANTI
} infoHeader;

struct pixel
{
	unsigned char r,g,b;
} pix[1002];

int main(int argc, char *argv[]) {
	unsigned int j;
	int width,flag;
	char buff[16];
	//FILE DI LETTURA E SCRITTURA
	FILE *input=fopen("prova.bmp","rb"),*output=fopen("BUFF.bmp","wb");
	
	printf("*************************************************\n"
	   	"* Primo effetto:inserire \"1\" e premere invio    *\n"
	   	"* Secondo effetto: inserire \"2\" e premere invio *\n"
	   	"*************************************************\n"
		"\n:");
	scanf(" %d",&flag);
	
	//LETTURA DATI
	fread(&bfType,sizeof(short),1,input);
	fread(&fileHeader,sizeof(fileHeader), 1, input);
	fread(&infoHeader,sizeof(infoHeader), 1, input);
	fseek(input, fileHeader.bfOffBits , SEEK_SET);
	
	width=infoHeader.biWidth;
	fwrite(&bfType,sizeof(short),1,output);
	fwrite(&fileHeader,sizeof(fileHeader), 1, output);
	fwrite(&infoHeader,sizeof(infoHeader), 1, output);
	fseek(output, fileHeader.bfOffBits , SEEK_SET);
	
	while(!feof(input)){
		fread(pix,sizeof(pix[0]) * width + 2, 1, input);
		for (int i=0;i<width;i++) {
			if (flag == 1) {
				//PRIMO EFFETTO
				pix[i].r = (pix[i].r + pix[i].g + pix[i].b )/3;
				pix[i].g = pix[i].r;
				pix[i].b = pix[i].r;
			}else{
				//SECONDO EFFETTO
				pix[i].r = 0 - pix[i].r;
				pix[i].g = 0 - pix[i].g;
				pix[i].b = 0 - pix[i].b;
			}
		}
		fwrite(pix,sizeof(pix[0]) * width + 2, 1, output);
	}
	printf("FATTO\n");
	//CHIUSURA DEI FILE
	fclose(input);
	fclose(output);
	return 0;
}