What is MIME type "video/x-jng"?

A MIME type is a string that tells browsers and other tools how to handle a particular kind of file.

The video/x-jng MIME type identifies files using the JNG format. It was defined as part of the MNG (Multiple-image Network Graphics) suite.

Despite the “video” prefix, this type handles still images. The format combines JPEG-style compression for color data with lossless methods for the alpha channel. This mix supports high-quality graphics with smooth transparency.

Main use: Display high-quality images with transparent areas.
Component in animation containers where still images play a role.
Facilitates blending lossy and lossless compression techniques.

This MIME type is mostly seen in specialized multimedia projects and legacy systems. For more details, visit MNG on Wikipedia.

Associated file extensions

.jng

Usage Examples

HTTP Header

When serving content with this MIME type, set the Content-Type header:


    Content-Type: video/x-jng

HTML

In HTML, you can specify the MIME type in various elements:


    <a href="file.dat" type="video/x-jng">Download file</a>

Server-side (Node.js)

Setting the Content-Type header in Node.js:


    const http = require('http');    
    
    http.createServer((req, res) => {    
      res.setHeader('Content-Type', 'video/x-jng');    
      res.end('Content here');    
    }).listen(3000);

Associated file extensions

.jng

FAQs

Why is the MIME type video/x-jng used for still images?

The video/ prefix is a historical artifact because JNG is a sub-format of MNG (Multiple-image Network Graphics), which handles animations. JNG files are essentially JPEG images with an added alpha channel (transparency) intended to be used as frames or components within MNG video streams.

Do modern web browsers support .jng files?

No, major browsers like Chrome, Firefox, and Safari do not natively support the video/x-jng type or JNG files. If you need to display these images on a website, you must convert them to standard formats like image/png or modern formats like WebP that support transparency.

How do I configure Apache to serve JNG files correctly?

To ensure your Apache server sends the correct video/x-jng header, add the following line to your .htaccess file or main server configuration: AddType video/x-jng .jng.

What is the advantage of JNG over standard JPEG?

A standard image/jpeg does not support transparency. The JNG format allows for the high compression ratios of JPEG while adding a lossless alpha channel (transparency), a feature usually reserved for larger PNG files. However, modern formats like WebP now offer this same capability with better compatibility.

How do I add video/x-jng support to Nginx?

You can define the MIME type in your Nginx configuration. Open your mime.types file (often in /etc/nginx/) and add the line: video/x-jng jng;. Be sure to reload the server with sudo service nginx reload to apply the changes.

How can I open or convert a .jng file?

Because standard operating system viewers rarely support this format, you will need specialized image viewing software like XnView, IrfanView, or Konvertor. These tools can display the image and convert it to a more common format like JPG or PNG.

General FAQ

What is a MIME type?

A MIME (Multipurpose Internet Mail Extensions) type is a standard that indicates the nature and format of a document, file, or assortment of bytes. MIME types are defined and standardized in IETF's RFC 6838.

MIME types are important because they help browsers and servers understand how to process a file. When a browser receives a file from a server, it uses the MIME type to determine how to display or handle the content, whether it's an image to display, a PDF to open in a viewer, or a video to play.

MIME types consist of a type and a subtype, separated by a slash (e.g., text/html, image/jpeg, application/pdf). Some MIME types also include optional parameters.

How do I find the MIME type for a file?

You can check the file extension or use a file identification tool such as file --mime-type on the command line. Many programming languages also provide libraries to detect MIME types.

Why are multiple MIME types listed for one extension?

Different applications and historical conventions may use alternative MIME identifiers for the same kind of file. Showing them all helps ensure compatibility across systems.