def compress(src, fmt="png"):
			fmt = fmt or "png"
			cmd = {
				"bmp": [ "ffmpeg", "-i", "pipe:0", "-f", "image2", "-codec:v",   "bmp", "pipe:1" ],
				"tga": [ "ffmpeg", "-i", "pipe:0", "-f", "image2", "-codec:v", "targa", "pipe:1" ],
				"png": [ "ffmpeg", "-i", "pipe:0", "-f", "image2", "-codec:v",   "png", "-compression_level", "9", "-pred", "mixed", "pipe:1" ],
				"jpg": [ "ffmpeg", "-i", "pipe:0", "-f", "image2", "-codec:v", "mjpeg", "-global_quality", "75", "pipe:1" ]
			}
			cmd = cmd[fmt] if fmt in cmd else cmd["png"]
			try:
				proc = Popen(cmd, stdout=PIPE, stdin=PIPE, stderr=PIPE)
				res = proc.communicate(input = src)
				out = res[0] ; err = res[1] ; msg = err.decode("ascii")
				if proc.returncode != 0:
					raise Exception(f"ffmpeg: {msg}")
			except Exception as e:
				out = src
				print(f"Error: {str(e)}")
				# raise e
			return out