solv.py

d = open('report2.xls', 'rb').read()

data_chunk = -1

start_address = [0xace1,
				 0xcc88,
				 0xecac,
				 0x10cd0,
				 0x12cf4,
				 0x14d18,
				 0x16d3c,
				 0x18d60,
				 0x1ad84,
				 0x1cda8,
				 0x1edcc,
				 0x20df0,
				 0x22e14,
				 0x24e38,
				 0x26e5c,
				 0x28e80,
				 0x2aea4,
				 0x2cec8,
				 0x2eeec,
				 0x30f10,			#301
				 0x30f10+0x2024,	#302
				 0x30f10+0x2024*2,	#303
				 0x30f10+0x2024*3,	#304
				 0x30f10+0x2024*4,	#305
				 0x30f10+0x2024*5,
				 0x30f10+0x2024*6,
				 0x30f10+0x2024*7,
				 0x30f10+0x2024*8,	#309
				 0x30f10+0x2024*9,
				 0x30f10+0x2024*10,	 #311
				 0x30f10+0x2024*11,	 #312
				 0x30f10+0x2024*12,	 #313
				 0x30f10+0x2024*13,	 #314
				 0x30f10+0x2024*14,	 #315
				 0x30f10+0x2024*15,	 #316
				 0x30f10+0x2024*16,	 #317
				 0x30f10+0x2024*17,	 #318
				 0x30f10+0x2024*18,	 #319
				 0x30f10+0x2024*19,	 #320
				 0x30f10+0x2024*20,	 #321
				 0x30f10+0x2024*21,	 #322
				 0x30f10+0x2024*22,]
cnt = len(start_address)-2
lens = [0x2020-0x4D-0x30]
#lens.append(0x4d)
lens.extend([0x2020]*cnt)
lens.append(0X1B9E)

has_data = False
addr = None
def get_data():
	global data_chunk, addr

	while True:
		data_chunk += 1
		print(f'Next chunk {data_chunk}')
		if data_chunk >= len(start_address):
			print('Finished')
			break

		off = start_address[data_chunk]
		addr = off
		l = lens[data_chunk]
		data = d[off:off+l]		

		for c in data:
			yield c,addr
			addr += 1

i = 0

from struct import pack, unpack
file_data = bytearray()
_iter = get_data()
temp = bytearray()

for c,a in _iter:
	print(f'{a:4X}')
	temp.append(c)
	if b'IDAT' == temp[-4:]:
		if i == 0:
			file_data.extend(temp)
		else:
			l = list(temp)
			print(f'Ditching {len(temp)-8} chars.')
			file_data.extend(l[-8:])
		temp = bytearray()
		print(f'Contains IDAT chunk.')
		size = file_data[-8:][0:4]
		print(size)	
		chunk_len = unpack(">I",size)[0]
		print(f'Size: {chunk_len}.')
		for r in range(chunk_len+4):	#data + crc			
			p,a = next(_iter)
			print(f'{a:4X}')
			file_data.append(p)

		i += 1
		print(f'PNG IDAT chunk {i}')

	if b'IEND' == temp[-4:]:
		p,a = next(_iter)
		temp.append(p)
		p,a = next(_iter)
		temp.append(p)
		p,a = next(_iter)
		temp.append(p)
		p,a = next(_iter)
		temp.append(p)
		break
	
	if i == 50:
		break

if len(temp) > 0:
	file_data.extend(temp)


open('file.png','wb').write(file_data)