CONVERSION DE FICHIER EN FICHIER BMP

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>

int main(int argc, char *argv[])
{
	/* BMP header */
	char BM[2] = "BM"; //Magic number
	int FileSize; //Size of the BMP file
	short Creator1 = 0; //Unused
	short Creator2 = 0; //Unused
	int DataStart = 54; //Offset where the pixel array (bitmap data) can be found
	/*DIB header */
	int DIB = 40; //Number of bytes in the DIB header (from this point)
	int Width;
	int Height;
	short ColorPlanes = 1;
	short BitsPerPixel = 24;
	int Compression = 0; //BI_RGB, no pixel array compression used
	int DataSize; //Size of the raw data in the pixel array (including padding)
	int HorizontalResolution = 0;
	int VerticalResolution = 0;
	int ColorPalette = 0; //Number of colors in the palette
	int ImportantColors = 0; //0 means all colors are important
	/*Data start */
	
	char RawName[FILENAME_MAX], BmpName[FILENAME_MAX] = "bmp.bmp";
	if(argc > 1)
	{
		strcpy(RawName, argv[1]);
		if(argc > 2)
			strcpy(BmpName, argv[2]);
	}
	else
	{
		printf("bmp [RawFile]\n");
		return -1;
	}

	FILE *raw = fopen(RawName, "rb+");
	if(raw == NULL)
	{
		printf("File \"%s\" not found.\n", RawName);
		return -1;
	}
	FILE *bmp = fopen(BmpName, "wb");
	if(bmp == NULL)
	{
		printf("Can not create \"%s\".\n", BmpName);
		return -1;
	}
	fseek(raw, 0, SEEK_END);
	DataSize = ftell(raw); //donnees
	int tmp = DataSize;
	while(1)
	{
		if(tmp%3 == 0 && tmp%4 == 0 && (float)sqrt(tmp/3)-(int)sqrt(tmp/3) == 0 && (int)sqrt(tmp/3)%4 == 0) //Pour avoir un nombre de données multiple de 3 (RGB), aucun padding (multiple de 4), ainsi qu'un carre.
			break;
		else
			tmp++;
	}
	printf("Bits de plus : %d\n", tmp-DataSize);
	Width = sqrt(tmp/3);
	Height = sqrt(tmp/3);

	DataSize = tmp;
	FileSize = 54 + DataSize;//header + donnees
	printf("File Size = %d bits (%.0f kb)\n", FileSize, (float)FileSize/1024);
	
	fwrite(BM, 1, 2, bmp);
	fwrite(&FileSize, 4, 1, bmp);
	fwrite(&Creator1, 2, 1, bmp);
	fwrite(&Creator2, 2, 1, bmp);
	fwrite(&DataStart, 4, 1, bmp);
	fwrite(&DIB, 4, 1, bmp);
	fwrite(&Width, 4, 1, bmp);
	fwrite(&Height, 4, 1, bmp);
	fwrite(&ColorPlanes, 2, 1, bmp);
	fwrite(&BitsPerPixel, 2, 1, bmp);
	fwrite(&Compression, 4, 1, bmp);
	fwrite(&DataSize, 4, 1, bmp);
	fwrite(&HorizontalResolution, 4, 1, bmp);
	fwrite(&VerticalResolution, 4, 1, bmp);
	fwrite(&ColorPalette, 4, 1, bmp);
	fwrite(&ImportantColors, 4, 1, bmp);
	
	printf("Creating %s...\n", BmpName);
	char *p = calloc(DataSize,sizeof(char)); //calloc pour avoir des 0 (noir) pour les pixels supplementaires
	if(p == NULL)
	{
		printf("Dynamic memory allocation failed.\n");
		return -1;
	}
	fseek(raw, 0, SEEK_SET);
	fread(p, 1, DataSize, raw);
	fwrite(p, 1, DataSize, bmp);

	printf("%s created.\n", BmpName);
	free(p);
	
	fclose(raw);
	fclose(bmp);
}