A GIF file or image is a raster file extension developed to support relatively simple online images. GIF stands for Graphic Interchange Format, and it can be identified using various single-byte sentinels, including the trailer, the extension block, the image type, or the “.gif†file extension.
GIF images are smaller in size but comparatively larger than WEBP files. Unlike lossy JPG files, smaller files download faster without distorting image quality. GIF’s ability to retain quality after compression makes it appropriate for image backgrounds with limited computing resources and bandwidth, unlike JPG and PNG.
GIF files or images have two close variations, GIF89a and GIF87a, using the .gif file extension. GIF89a file is the newly improved GIF version with animations and transparency capabilities. On the other hand, GIF87a serves as the original GIF file format used in indexed colored images.
GIF's most unique attributes include support for animation, transparency, and a wide color channel. It allows website owners and developers to merge image background animations, colors, and images to develop inventive website designs. GIF supports the color image format for the download region.
History of GIF files
GIF boasts a rich history dating back to the early 1980s when Steve Wilhite started working on the file format. However, CompuServe Ltd. created and launched its first version in June 1987 to replace the old black-and-white Run Length Encoding (RLE) file format.
GIF immediately became popular among browsers because it used the efficient Lempel Ziv Welch data compression technique, which is uncommon in other file formats. CompuServe encouraged users to adopt the file format because it offers downloadable conversion capabilities for most computers.
GIF image formats are of different types: technical GIF, Perfect Loop GIF, Cinemagraph GIF, and Reaction GIF. The Technical GIF creates exciting image information, including graphs, diagrams, or product descriptions, using dull data.
The Perfect Loop GIF integrates event information through smooth looping, making it livelier. It combines recorded events, which are smoothly lopped. Conversely, the Reaction GIF expresses feelings and reactions by enhancing online users’ comments.
The Cinemagraph GIF is a fusion of animation and photography. It integrates slight regions of motion, namely city streets or distant waterfalls, giving accompanying images of peaceful tones and professional appearance.
GIF images or file formats were created to help solve the problem of limited device capacities and bandwidth during the early periods of the Internet. The compression technique used in GIF enhanced the ability to serve image content online with standard performance.
GIF enables the integration of many frames or images into a single image file and sequential display to produce a short video or animated clip. Thus, it led to the creation of video formats and compressed animated GIFs while accelerating the speed of downloading large images.
GIF has become increasingly popular and a comical internet sensation. Over the last three and a half decades, it has helped complete browsers' favorite group chats. It makes communication easier across social media platforms, making it a popular go-to globally.
Reaction GIF file images, typically video-based, have taken over social media platforms and instant messaging. Besides, GIF videos are usually quick and funny clips from TV scenes or movies, attracting many viewers worldwide.
The consistency and instant delivery make it even more popular. For example, ‘Friends’, the famous NBC TV show, used multiple GIF file formats based on favorite lines and scenes from GIPHY characters, resulting in 1 billion views.
Properties of GIF files
GIF files have many features, including a limited color palette, dithering, LZW compression, support for transparency, interlacing, and animation, and perfect on-screen broadcasting resolution.
Structure
A GIF file or image is a raster graphics file format created or developed for comparatively simple images that appear mainly online. The GIF structure defines the logical screen with a graphical range of static size.
The screen either contains zero, one, or even multiple images. It splits the screen into discretely smaller pictures or a distinct image filling the logical screen. The images operate like animation edges in lively GIF files.
The file format begins with a fixed-length header such as GIF89a or GIF87a. The file offers the logical screen descriptor and file version with fixed length but specifies more GIF features and the logical screen scales in pixels.
The logical screen checks for the presence of the Global Color Table and size description. The GIF file then divides into segments led by a one-byte sentinel, including an image, extension block, and trailer.
The GIFs image module starts with a fixed-length picture descriptor specifying a global color table's presence and size. The descriptor is followed by image data having one byte that provides the unencoded icon width.
The image data is followed by an allied list comprising sub-blocks that define information encrypted using the LZW compression algorithm. The extension block stretches the GIZ87a description using a pre-defined tool from the GIF87a specifications.
Every block comprises a byte specifying the kind of extension and a sentinel, trailed by a related list with a sub-block for the extension info. The extension block modifying the GIF image heads the GIF file subdivision that contains the applicable image.
The image data and extension blocks utilize connected lists comprising various sub-blocks. A single byte starts each sub-block and specifies the quantity of data bytes following it inside the sub-block. Every sub-block sequence concludes with a blank or zero-byte sub-block.
GIF is considered a low-quality file format because it supports only 8 bits per pixel and holds a maximum or limited color space of 256 indexed colors. The bit depth allows a single GIF file to reference its palette of up to 256 various colors. Besides, GIF permits multi-sample pixels.
The file format can store multiple images per file. For instance, GFI87a offered support for multiple images per stream. It incorporated multiple blocks, each with a 256-color palette, and every block was tiled to make a comprehensive image.
The colors are selected from the 24-bit RGB color space. Nevertheless, the format supports multiple images in a single file but allows separate palettes containing 256 colors for every frame. While it accesses over 16.8 million colors, a single GIF image can only reference a maximum of 256 colors.
The GIF file’s size limit should be below 2MB and 3MB. This is the maximum file size for any text documents or messages, implying that for a GIF file to be sent as a text message, it should be smaller than these limits.
GIF is a low-resolution file format. Its smaller pixel dimensions are necessary for low-resolution apps, thumbnails, or simple web displays. Most GIF images have resolutions from 72 dpi to 90 dpi, which are only perfect for on-screen broadcasting.
Storage
GIF data are stored in an interlaced and compressed format. The storage mediums for such files or data are hard drives, floppy drives, file systems, cloud storage, and Content Delivery Network (CDN). Depending on the conditions, GIF files can be stored indefinitely if appropriately handled.
Compression
The GIF image format uses lossless compression and the Lempel Ziv Welch (LZW) algorithm to compress image data. The decompressed image file becomes smaller during compression and preserves its quality, remaining identical to the original image.
GIF files support variable compression. Both lossless compression and LZW algorithm techniques include a multi-prolonged image transformation process, which is the basis of GIF lossless encoding.
The image is transformed by altering color space, merging local palettes, replacing alpha channels, spatial prediction of pixels, and merging different pixels in one pixel.
The GIF compression process is multi-prolonged. The file format uses Lempel Ziv Welch's (LZW) lossless compression technique to compress its files by allowing images to fit into smaller pictures and files.
The Lempel Ziv Welch (LZW) compression algorithm exploits repetition in information streams to efficiently store simple graphical images while taking advantage of flat colors.
GIF image compression is necessary when a less detailed file is needed. GIF’s lossless compression ensures users get smaller images without losing or distorting image quality. The smaller and less detailed file sizes increase website responsiveness or reduce web loading time.
Editing
GIF files support and are compatible with video editing programs such as Photoshop, Flixier, Kapwing, Imgflip, Canva, PhtoDirector 365, GIPHY, and Makeagif.
GIF images can be resized, and all image qualities can be preserved. Resizing its images reduces the physical dimensions and the quantity of information in a GIF file to the recommended sizes.
GIF files can be resized using Photoshop, Makegif, GIPHY, PhotoDirector, and Imgflip.
Animation
GIF supports animation. The GIF89a has specs that add various enhancers to the GIF image file header, allowing browsers to show many GIF pictures in a looped series or scheduled sequence.
The frames and images of a GIF file can be joined together to create basic animations. Nonetheless, the mechanism only permits the creation of small, crude animations.
Animated GIFs have numerous benefits. First, unlike animated PNG, animated GIFs allow for basic animation. Second, animated GIFs are easy to update and injectable, permitting a quick and pleasant iterative update cycle.
Third, animated GIFs can instantaneously hold multiple frames or images, giving them a video-like effect. Such a feature is not expected to be animated in PNG.
Animated GIFs similarly have disadvantages compared to animated PNG formats. First, unlike animated PNGs with flexible edges, animated GIFs have fixed edges or binary transparency that becomes blurry when scaled up.
Second, animated GIFs cannot be edited after LZW lossless algorithm compression, while animated PNGs can be edited. Animated PNGs are not flexible, while animated GIFs are flexible.
Transparency
GIF file or image format supports transparency. The GIF89a format has a transparency feature called the alpha channel, which permits the arrangement of one of the palette colors to be ignored.
The alpha channel simultaneously processes the image to be displayed on a device and its transparent backgrounds, giving such images a professional look.
Best uses of GIF Files
Suitable for designing simple logos and web graphics, which feature sharp edges, lines, and relatively few colors.
It is suitable for creating flip-book effects because it can integrate various related images, which gives a soundless video impression.
Suitable when creating humorous clips, online animations, and memes widely used across social media platforms.
Unrecommend use of GIF Files
It is unsuitable for online images such as photographs, making websites look unpredictable or fragmented.
GIF Browsers Support
A GIF file or image is supported by almost all old and modern Browsers like:
- Vivaldi
- Google Chrome
- Mozilla Firefox
- Safari
- Microsoft Edge
- Opera
- Internet Explorer
GIF is widely used and supported by most social media platforms, including:
- X (formerly Twitter)
- MySpace
- YouTube
- Snapchat
Possible GIF Browser Errors
The likely errors encountered when using GIF files include:
- Wrong file uploaded
- Server-test failure
- File not found error
- Corrupted file error
- File not supported error
Advantages of GIF
- Small File Size: GIF image files are small in size, download quickly, and hardly distort image quality during LZW lossless compression.
- Transparent Background: GIF supports different transparent backgrounds, allowing diverse animations, images, and color backgrounds to be merged easily.
- Easily Supports Animation: GIF supports the creation and consumption of animations on different devices, allowing developers, web owners, and designers to deliver an improved audience experience.
- Dithering: GIF uses designs of the adjacent pixels to excite the appearance of the inconspicuous colors while adding noise to an image and decreasing sharpness.
- Interlacing: The interlacing mechanism enables GIF images to look nearer to the screen as it displays a low-resolution image version and then progressively displays the complete version.
Disadvantages of GIF
- Heavier or Larger Files: GIF images load slower on webpages because their file sizes are heavier than those of other optimized WEBP video file formats.
- Cannot be Edited: Animated GIFs can hardly be edited since the animation and frames are encoded inside the files.
- Limited Color Schemes: Animated GIFs and GIFs only support 256 color palettes, making them appear less detailed and unattractive than other file formats.
- Pixelated: GIF images are often slightly pixelated or jagged.
How to open GIF
GIF files can be opened in software such as Bitberry File Opener, Free File Viewer, Irfan View, Corel PaintShop Pro, Adobe Photoshop, ACDSee, HoneyView3, SyncUp, QuickTime, ImageMagick, and Pixillion Image Converter.
GIF is compatible with nearly all operating systems, including Windows, iOS, Windows Vista, macOS, Android, and Linux. These operating systems have built-in programs that support GIF files.
Converting GIF
GIF files can be easily converted to different image formats or file types, such as JPEG, AVIF, JPG, and PNG. You can check out our full list of online GIF converters to test what is possible.