vendredi 30 octobre 2015

The fastest way to read binary files by bytes in Python

I am making a program, which should be able to encode any type of file using huffman algorithm. It all works, but using it on large files is too slow (at least I think it is). When I tried to open an 120MB mp4 file to unpack it, it took me about 210s just to read the file. Not to mention that it took a large chunk of memory to do so. I thought unpacking using struct would be efficient, but it isnt. Isn't there more effiecent way to do it in python? I need to read any file by bytes and then pass it to the huffman method in string.

if __name__ == "__main__":
    start = time.time()
    with open('D:\mov.mp4', 'rb') as f:
        dataL = f.read()
    data = np.zeros(len(dataL), 'uint8')

    for i in range(0, len(dataL)):
        data[i] = struct.unpack('B', dataL[i])[0]

    data.tostring()

    end = time.time()
    print("Original file read: ")
    print end - start

    encoded, table = huffman_encode(data)

Aucun commentaire:

Enregistrer un commentaire