How do I convert a binary image into an in-memory data structure in python?

Question

Context:

Goal:

Read a binary image file and represent it in-memory. Then run a checksum on it. Deliver the binary representation to be stored as a blob in mysql.

Comments:

I have read this SO thread.
I have looked at the struct module.
I also have bumped into the io module.
With all the available options, I am not certain which is the best solution. The BytesIO data structure seems to be suitable for my needs. Which one do you think will meet my requirements ?

When you read the blob back from mysql, will you be working with it as an image or just writing it back to a file? — Mark Ransom, Feb 22 '12 at 21:42
Please up vote and select one of the 2 below and select an answer if applicable — Matt Alcock, Feb 23 '12 at 00:13

score 4 · Answer 1 · edited Aug 11 '13 at 14:54

4

I'd recommend using PIL (Python Image Library)

Save it down to a string and then write to the db. Then you can use the string butter interface to PIL to read it back out.

edited Aug 11 '13 at 14:54

Jonathan Root

answered Feb 22 '12 at 21:37

Matt Alcock

score 0 · Accepted Answer · answered Feb 22 '12 at 12:40

0

>>> from binascii import crc32
>>> with open(filename, "rb") as f:
...     data = f.read()
...
>>> crc32(data)
361260080

answered Feb 22 '12 at 12:40

Janne Karila

This calculates a checksum of the file, not the checksum of image data. . This means it will generate a different checksum for 2 .pngs with identical image but different metadata. Might be relevant – Kos Aug 11 '13 at 14:57

2 Answers2