Just for the record. It is merely used to represent binary data using printable characters. But not only for Magento, for any source code which is encrypted using base Thanks Pavel. Agree, forgot to mention that for default abse64 even if I often use both of the functions to check some values…. You should also use urlencode function before sending and urldecode while accepting data to be sure that there is no any encoding error in your query string.
Your email address will not be published. Does gmail use base64? You can also build your own base64 algorithm for your specific needs! Stay tuned! Published in: Administration Debugging Magento. You made it all the way down here so you must have enjoyed this post! You may also like: Zrinka Antolovic , Oct 08, 4. Zrinka Antolovic , Oct 15, 6. Aron Stanic , Apr 09, 0. The images are binary data, while the XML document is text. But XML cannot handle embedded binary data.
So how do you do it? One option is to encode the images in base64, turning the binary data into text that XML can handle. Why not look to the RFC that currently defines Base64? Base encoding of data is used in many situations to store or transfer data in environments that, perhaps for legacy reasons, are restricted to US-ASCII [1] data.
Base encoding can also be used in new applications that do not have legacy restrictions, simply because it makes it possible to manipulate objects with text editors. In the past, different applications have had different requirements and thus sometimes implemented base encodings in slightly different ways. Today, protocol specifications sometimes use base encodings in general, and "base64" in particular, without a precise description or reference.
Multipurpose Internet Mail Extensions MIME [4] is often used as a reference for base64 without considering the consequences for line-wrapping or non-alphabet characters. The purpose of this specification is to establish common alphabet and encoding considerations. This will hopefully reduce ambiguity in other documents, leading to better interoperability.
Base64 was originally devised as a way to allow binary data to be attached to emails as a part of the Multipurpose Internet Mail Extensions. Media that is designed for textual data is of course eventually binary as well, but textual media often use certain binary values for control characters. Also, textual media may reject certain binary values as non-text.
It is more that the media validates the string encoding, so we want to ensure that the data is acceptable by a handling application and doesn't contain a binary sequence representing EOL for example. Imagine you want to send binary data in an email with encoding UTF-8 -- The email may not display correctly if the stream of ones and zeros creates a sequence which isn't valid Unicode in UTF-8 encoding.
All we are doing is ensuring there is a 1-to-1 mapping between a known good, acceptable and non-detrimental sequence of bits to another literal sequence of bits, and that the handling application doesn't distinguish the encoding. In your example, man may be valid ASCII in first form; but often you may want to transmit values that are random binary ie sending an image in an email :.
MIME-Version: 1. Here we see that a GIF image is encoded in base64 as a chunk of an email. The email client reads the headers and decodes it. I'll give you a very different but real example: I write javascript code to be run in a browser.
But I want my ID to losslessly refer to files in my file system. Files in reality can have all manner of weird and wonderful characters in them from exclamation marks, accented characters, tilde, even emoji!
I cannot do this:. With Base64 I can refer to something complicated without worrying about which language allows what special characters and which need escaping:. Unlike using an MD5 or some other hashing function, you can reverse the encoding to find out what exactly the data was that actually useful. I wish I knew about Base64 years ago.
If you're trying to pass complex data over ssh e. This is how you would do it with base 64 I know you can use SCP, but that would take multiple commands - which complicates key bindings for sshing into a server :.
One example of when I found it convenient was when trying to embed binary data in XML. Some of the binary data was being misinterpreted by the SAX parser because that data could be literally anything, including XML special characters. Base64 encoding the data on the transmitting end and decoding it on the receiving end fixed that problem. Most computers store data in 8-bit binary format, but this is not a requirement. Some machines and transmission media can only handle 7 bits or maybe even lesser at a time.
Such a medium would interpret the stream in multiples of 7 bits, so if you were to send 8-bit data, you won't receive what you expect on the other side. Base is just one way to solve this problem: you encode the input into a 6-bit format, send it over your medium and decode it back to 8-bit format at the receiving end. That those protocols were designed to handle text often, only English text instead of binary data like.
But the converse is not true. A protocol designed to represent text may improperly treat binary data that happens to contain:. So you can't just send binary data over a text-based protocol. You're limited to the bytes that represent the non-space non-control ASCII characters, of which there are The reason Base 64 was chosen was that it's faster to work with powers of two, and 64 is the largest one that works.
One question though. How is that systems still don't agree on a common encoding technique like the so common UTF-8? On the Web, at least, they mostly have. A majority of sites use UTF And the fact that Microsoft seems to have still not gotten over having picked the wrong UTF encoding. This makes it painful to use UTF-8 because you have to convert all the time. In addition to the other somewhat lengthy answers: even ignoring old systems that support only 7-bit ASCII, basic problems with supplying binary data in text-mode are:.
It is used so that typical binary data such as images may be safely sent over legacy "not 8-bit clean" channels. So many early comm protocol standards were designed to work over "7-bit" comm links "not 8-bit clean". Scheme efficiency is the ratio between number of bits in the input and the number of bits in the encoded output. People jumped through all sorts of hoops to get these transferred over the wire without losing out information.
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