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copied!<p>Byte sequences in Python are represented using strings. The series of letters and symbols that you see when you print out a byte sequence is merely a printable representation of bytes that the string contains. To make use of this data, you usually manipulate it in some way to obtain a more useful representation.</p> <p>You can use <code>ord(x)</code> or <code>bin(x)</code> to obtain decimal and binary representations, respectively:</p> <pre><code>>>> f = open('/tmp/IMG_5982.JPG', 'rb') >>> data = f.read(10) >>> data '\x00\x00II*\x00\x08\x00\x00\x00' >>> data[2] 'I' >>> ord(data[2]) 73 >>> hex(ord(data[2])) '0x49' >>> bin(ord(data[2])) '0b1001001' >>> f.close() </code></pre> <p>The <code>'b'</code> flag that you pass to <code>open()</code> does not tell Python anything about how to represent the file contents. From <a href="http://docs.python.org/library/functions.html#open" rel="nofollow">the docs</a>:</p> <blockquote> <p>Append 'b' to the mode to open the file in binary mode, on systems that differentiate between binary and text files; on systems that don’t have this distinction, adding the 'b' has no effect.</p> </blockquote> <p><em>Unless you just want to look at what the binary data from the file looks like, Mark Pilgrim's book, Dive Into Python, has <a href="http://www.faqs.org/docs/diveintopython/fileinfo_divein.html#fileinfo.divein" rel="nofollow">an example</a> of working with binary file formats.</em> The example shows how you can read IDv1 tags from an MP3 file. The book's website seems to be down, so I'm linking to a mirror.</p>

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