Question

i converted the output XImage of my code to Bitmap, but the output file is massive, so i thought about compressing it using lzrw
i use this code to write the bitmap to file

fwrite(&bmpFileHeader, sizeof(bmpFileHeader), 1, fp);
fwrite(&bmpInfoHeader, sizeof(bmpInfoHeader), 1, fp);
fwrite(pImage->data, 4*pImage->width*pImage->height, 1, fp);

is there anyway i could write it to a (char *) insted of (FILE *) so i can use lzrw compression on it?
or even better, some way to convert the XImage to PNG directly…

thanks;

Answer 1

Use memcpy instead of fwrite

char* tmp = buf;
memcpy(tmp, &bmpFileHeader, sizeof(bmpFileHeader));
tmp += sizeof(bmpFileHeader);
memcpy(tmp, &bmpInfoHeader, sizeof(bmpInfoHeader));
tmp += sizeof(bmpInfoHeader);
memcpy(tmp, pImage->data, 4*pImage->width*pImage->height);

EDIT: I update code, thaks @bdk for pointing out