为什么我的 Python 读取的位比我设置的多？

Question

I'm trying to read the values from a binary file but I'm having some trouble. This is what I'm doing:

from struct import unpack

with open("pixelValues.txt", "rb") as f:
    byte = f.read(8)
    foo = unpack("<Q", byte)
    print(foo)

When I run the program the output is (4244912790557L,) which doesn't make sense to me because it should be 1485102109 . Does anyone see what I'm doing wrong?

Here is a screenshot of the file:

Answer 1

You're reading too much. Change f.read(8) to f.read(4) and change unpack("<Q", byte) to unpack("i", byte) and that will fix your problem.

Answer 2

pack('<Q', 1485102109) 

Returns:

'\x1d\xdc\x84X\x00\x00\x00\x00'

Which is not consistent with your file. How did you write it?

Edit:

You have written the number with a %d specifier, which means that you've written it as a 4-byte integer, not as an unsigned long long, but as an unsigned int. You should read it like this:

from struct import unpack

with open("pixelValues.txt", "rb") as f:
    num = f.read(4)
    foo = unpack("<I", num)
    print(foo)