I have some trouble in understanding how does html convert base64 to img
From https://www.lucidchart.com/techblog/2017/10/23/base64-encoding-a-visual-explanation/ I learn how string convert to base64,but what dose it happen when base64 encoding to rgb
Base64 is a way to encode binary data as text (so it can be put anywhere you can put text, such as in an HTML attribute value).
The browser converts the Base64 data into whatever form it was in originally.
If that was a PNG it converts it back to a PNG. If it was a JPEG then a JPEG. And so on.
The browser doesn't convert the Base64 data directly to pixel values at all.
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I have some text in a database that is encoded in some way, but I don't know what exactly, and the person who built the database and website left no documentation or comments of any kind. Ask an example, ÌÈÑÇä-1914 is stored in the database, but on the website, it is displayed as جبران-1914. How do I decode ÌÈÑÇä-1914 in order to get the Arabic text?
I've tried decoding ÌÈÑÇä-1914 into windows-1256, ISO-8859-1, UTF-8, but when I put it in an html file and lang-eg in the html tag, and meta charset=utf-8, but nothing is letting me display it as Arabic text instead of some indecipherable characters. How can I convert the encoded text into Arabic?
I realized the problem was that I was exporting the data incorrectly--when I exported it as ISO 8859-2 and converting it to windows 1256 in atom it displayed properly.
I am using angular 7 and need to upload image and send it to server to put it in database. So i wondering how to convert image into string and latter back in image so i can display it in app?
This SO answer explains how to convert an image into base64 encoded data.
You can use the HTML5 for it:
Create a canvas, load your image into it and then use toDataURL() to
get the base64 representation (actually, it's a data: URL but it
contains the base64-encoded image).
I don't think that's how you want to save your images though. Continue researching perhaps.
Let's suppose that an chracter encoding format called X exists (for example UTF-8), if I insert in the HTML file the tag <meta charset="X"> and then I save the file, obviously, with the same encoding, how can the broswer read the file later?
I mean, how can the broswer know the encoding of an HTML page if, to get encoding, it must read the file? It seems a sort of loop.
According to https://www.w3.org/TR/html4/charset.html#h-5.2.2, a browser gets the correct encoding from the Content-Type header field of the HTTP response. If this field is not present, the browser reads the HTML page until the META tag, assuming all bytes were ASCII characters. So this only works if ASCII is a subset of the actual encoding.
I know how to convert the common NSAttributedString (which has no image) into HTML. I set the Images as NSTextAttachment to NSAttributedString (these attributed strings are set as attributeText of a UITextView). How could I convert the whole attributed string into HTML?
I‘ve found an answer related solution,which mentions:
Simple idea for image: encode it with base64 and put it directly in a < img > tag with the right frame.
But how could i implement that?
I have an HTML text input to store the base64 string from an image canvas.
Apparently when I tried sending a long base64 string to the server, part of the string is not sent which results in grayed out image.