.JNG File Extension
JPEG Network Graphic
| Developer | PNG Development Group |
| Popularity | |
| Category | Raster Image Files |
| Format | .JNG |
| Cross Platform | Update Soon |
What is an JNG file?
The JPEG Network Graphic (JNG) file format is a lesser-known cousin of the popular PNG (Portable Network Graphics) format.
It was designed to incorporate the best features of both JPEG (Joint Photographic Experts Group) and PNG formats, offering a versatile solution for handling images with both lossy and lossless compression.
JNG files are often used in situations where it’s beneficial to combine the strengths of JPEG’s compression efficiency with PNG’s support for transparency and lossless data.
More Information.
JNG was introduced in the late 1990s alongside the MNG format by the same group that developed PNG.
The primary goal was to offer an efficient image format that could leverage JPEG’s lossy compression to reduce file sizes while also supporting alpha transparency through an associated lossless grayscale or color image.
This combination made JNG a flexible choice for web graphics and other applications where transparency and efficient compression were required.
Origin Of This File.
The JNG format was created as part of the MNG (Multiple-image Network Graphics) suite of formats, which were developed to provide an animated image format that was free of patent restrictions.
The MNG format, which is an extension of the PNG format, aimed to replace the GIF format for animated images.
JNG, in this context, was designed to support the storage of individual frames in MNG animations using JPEG compression.
File Structure Technical Specification.
A JNG file is structured to include both a lossy JPEG-encoded color image and an optional lossless grayscale or color image for the alpha channel.
This allows for the storage of transparent images with efficient compression. The technical specifications of a JNG file are as follows:
- Signature: A JNG file starts with an 8-byte signature similar to PNG.
- Chunks: The file is divided into chunks, each serving a specific purpose. The main chunks include:
- JHDR (JPEG Header): Contains information about the color and alpha image, such as dimensions and bit depth.
- JDAT (JPEG Data): Stores the JPEG-compressed color image.
- IDAT (Image Data): Stores the optional lossless alpha image.
- IEND (Image End): Marks the end of the JNG file.
How to Convert the File?
Converting JNG files can be done using various image conversion tools and software. Here are some methods:
- Image Conversion Software: Programs like XnConvert, ImageMagick, and IrfanView can handle JNG files and convert them to other formats like PNG, JPEG, or TIFF.
- Online Converters: Websites like Online-Convert, Convertio, and Zamzar offer online tools to upload JNG files and convert them to more widely supported formats.
- Command Line Tools: For users comfortable with command line interfaces, tools like ImageMagick provide powerful options for converting JNG files.
Advantages And Disadvantages.
Advantages
- Efficient Compression: The use of JPEG compression for the color image allows for smaller file sizes compared to fully lossless formats.
- Alpha Transparency: Supports alpha channels, enabling transparency in images, which is not possible with standard JPEG files.
- Flexibility: Combines the benefits of JPEG and PNG, making it versatile for different use cases.
Disadvantages
- Limited Support: JNG is not widely supported by modern image viewers and web browsers, limiting its usability.
- Complexity: The format’s structure is more complex than JPEG or PNG alone, which can make implementation and processing more challenging.
- Lossy Compression: While efficient, the lossy nature of JPEG compression means that some image quality is sacrificed.
How to Open JNG?
Open In Windows
- XnView: A versatile image viewer that supports JNG files along with many other formats.
- IrfanView: Another popular image viewer with support for JNG through plugins.
- ImageMagick: A powerful tool for image manipulation that supports JNG.
Open In Linux
- ImageMagick: Available through most package managers, providing robust support for JNG files.
- GIMP: With the necessary plugins, GIMP can open and edit JNG files.
- XnViewMP: A cross-platform image viewer that supports JNG.
Open In MAC
- XnViewMP: The macOS version of XnView, supporting JNG files.
- ImageMagick: Can be installed via Homebrew and used to open and convert JNG files.
- GIMP: The GNU Image Manipulation Program can open JNG files with the proper plugin installed.
