I am new to XML. I have an XML document that I am inserting data manually. I wanted to know if it is possible to include an image in an XML file and not by using the file path. I have found something about encoding but I do not understand how this work and the option is not even available in the XML editor. After storing the images in the XML file, I will access it using javascript. Please provide further information on this matter.
An image is binary data, and the usual way to store binary data in an XML document is by encoding it in base64 (which turns it into ASCII characters). Libraries to convert from binary to base64, and back, are widely available, but the details depend very much on your programming environment. There are also online services where you can upload an image and get back its base64 representation: an example is here https://www.base64encode.net/base64-image-encoder
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I have a successfully running script that loads Word files from SharePoint and inserts them into Word 2017 (Office 365 Word local client, not online)
The current scripts reads up the files using Ajax and extracts the base64 file and uses
body.insertFileFromBase64(myBase64, end)
I now need to extend the functionality to support Word 2013 (i.e. use the Office.js instead of the Word JavaScript api). So the code has changed to
Office.context.document.setSelectedDataAsync(file, someCoercionType)
I hoped to be able to use a variant of
Office.context.document.setSelectedDataAsync(myBase64, {coercionType: Office.CoercionType.Ooxml}, function (
But I get an error back "The Format of the specified data object is invalid", which is correct enough as the Office API assumes a base64 file is an image.
Is it possible to convert the Base64 file to XML in JavaScript? (Elsewhere in my code I unzip the docx and extract bookmarks, but only from document.xml which lacks all formatting and images, footers etc.)
Base64 is simply an binary encoding and blissfully unaware of the underlying content type. So if you're source content was OOXML, decoding it would give you that OOXML back. What you cannot do is type conversion. For example, a Base64 encoded JPEG can not be decoded directly into a BMP. To do that you would need to first decode and then convert from JPEG to BMP using some other tool.
If you're seeking to manipulate or extract content an existing document, you may want to look at Aspose.Words. Aspose provides tools that allow you to programmatically work with Word documents (they have similar tools for a flew of other file types as well). Using this, you may be able to extract the OOXML you're looking for so you can then insert it into Word using Office.js.
At the moment, the only Coercion Type that accepts Base64 encoded content is Office.CoercionType.Image.
I am browsing the deck.gl repo. It ships with some examples with text files, for example this one. These files have a .txt extension, but aren't plain text:
!OohmwFjqwbMg#[?ADKJYXF#^?N?FAD
=wnmwFvvwbM_#WNg####C?C_#UA?AD#?Of#_#UTu#??BK?A??FUVP?#JF?AVP?#JF?AVPGTA?EL#?
=urmwF|swbM_#UFS##BK?C#C#A#E?CIGA?GE?CIGA#CF?#ABA#CJ##GR]Ud#wA\T?#DB?AXP?#DB?A\T
<aymwFnvwbMaAOKCA#OKPk#CCDKAADKAADKAADKAADKAAL_#fBjAIVCCEL
The examples also contain JavaScript files that look as though they are used to decode these files, for example this one for the file above.
What exactly is going on here? I assume this is a way of reducing the size of the data, but why not just rely on browser gzipping?
And why use a plain text extension when the file is clearly plain text? And why have a custom decoder at all?
It looks like a custom encoding that uses byte values to encode coordinates/GeoJSON features.
For example, this line from /dist-demo/data/building-data.txt:
!GqgmwFrhwbM}C}##K#IBO#IlBh#BOBMn#PHBGd#KC
is decoded using the decodePolyline() utility function into this array:
[
[0.00004,0.00001],
[40.70541,0.00002],
[40.7062,-74.01624],
[40.70619,-74.01593],
[40.70618,-74.01587],
[40.70616,-74.01582],
[40.70615,-74.01574],
[40.7056,-74.01569],
[40.70558,-74.0159],
[40.70556,-74.01582],
[40.70532,-74.01575],
[40.70527,-74.01584],
[40.70531,-74.01586],
[40.70537,-74.01605],
[40.70537,-74.01603]
]
which is substantially larger in JSON format.
So my guess would be that the main reason is to be able to use smaller data files that are still portable/cacheable. It's still line-based clear text, so it's diffable as well.
Also, these files are still compressible. I assume that a full JSON file is not only larger to begin with but also exhibits less favorable compression characteristics than this file. A quick test on building-data.txt shows a compression ratio of roughly 2:1 for gzip/deflate (139,089 bytes to 72,660 bytes compressed). The compression result for the same file in raw JSON won't be anywhere near that.
I have a REST service that returns a base64 representation of a file, could be any variety (assuming for now its application/pdf), and am wondering if there's a simple way to trigger the browser to save that base64 string into a file download that can be processed within JavaScript. I've looked at download.js but it doesn't seem to do what I intend it to do, unless its tied to a click event (something I really can't do here). Are there any other suggestions to implement this?
I heard a lot about Baase64 Encoding for Images in Webdesign.
And i saw a lot of developers they use it for thier headlines with: data:image/png;base64,iVBORw0...
Is there any automatism (with javascript) behind?
Or have they all converted & inserted ? (could not belive)
Example: http://obox-inkdrop.tumblr.com/ (- Headlines)
First of all, the encoding has to be done on the server-side, be it :
automated with a script, that reads the original image file, and returns the base64 encoded string to inject it into the HTML that's being generated
or by hand, and directly placed into the HTML.
The base64 encoding cannot be done on the client-side, as the goal is to avoid sending the image file from the server to the browser (to minimize the number of HTTP requests).
Depending of the language that's used on the server-side, you'll probably find some function to do base64 encoding.
In PHP, you might be interested by base64_encode()
I'll cut right to the chase. Right now I am developing a web based application. It has a PHP REST based architecture that serves up XML documents. On many of these documents attributes are hex encoded picture strings.
On the client side jQuery AJAX fetches an XML document with a picture in it. I need to display said picture in some <img> tags. However my knowledge on such methods is lacking so here I am asking for help.
Goal:
JavaScript String variable in hex or base64 >>> HTML displayed image.
Cross browser is required, or a hack for the ones that do not support it is fine.
Thanks,
Gunnar
Encode the images using base64 and write them out in a CDATA string into your XML with this format:
data:[<MIME-type>][;charset="<encoding>"][;base64],0123456789abcdefg...
When constructing your document, use this string as your src
<img src="data:image/png;base64,0123456789abcdefg..." />
Is it possible to use a php file just for rendering the image? That php file could write some base64 encoded values via
echo base64_decode($_GET['data']);
while you embed images like
<img src="http://host/yourPhpFileForDecode.php?data=base64encoded.../>