(Joint Photographic Experts Group) An ISO/ITU standard for compressing still images. Pronounced "jay-peg," the JPEG format is very popular due to its variable compression range. JPEGs are saved on a sliding resolution scale based on the quality desired. For example, an image can be saved in high quality for photo printing, in medium quality for the Web and in low quality for attaching to e-mails, the latter providing the smallest file size for fastest transmission over dial-up connections.
Not Great for Text
JPEGs are not suitable for graphs, charts and explanatory illustrations because the text appears fuzzy, especially at low resolutions. Compressing images in the GIF format is much better for such material (see GIF).
JPEGs Are Lossy
Using discrete cosine transform, JPEG is a lossy compression method, wherein some data from the original image is lost. It depends on the image, but ratios of 10:1 to 20:1 may provide little noticeable loss. The more the loss can be tolerated, the more the image can be compressed.
Compression is achieved by dividing the picture into tiny pixel blocks, which are halved over and over until the desired amount of compression is achieved. JPEGs can be created in software or hardware, the latter providing sufficient speed for real time, on-the-fly compression. C-Cube Microsystems introduced the first JPEG chip. See JPEG2000, JPE file and GIF.
File Extensions
JPEGs use the JPEG File Interchange Format (JFIF), and file extensions are .JPG or .JFF. M-JPEG and MPEG are variations of JPEG used for full-motion digital video (see MPEG). See graphics formats.
Saving JPEGs
At first glance, these two dialogs seem contradictory because the larger number means high quality in one and low quality in the other. Photoshop (top) uses a 1-to-12 scale for quality, while Epson (bottom) uses a percentage for the amount of compression. The more compression, the more loss in the result. Standard is the original JPEG format, while Optimized compresses more effectively. Progressive causes the image to display incrementally from top to bottom. Web users with slow connections see the image form on screen right away rather than wait for the entire file to download first.
Not Great for Text
JPEGs are not suitable for graphs, charts and explanatory illustrations because the text appears fuzzy, especially at low resolutions. Compressing images in the GIF format is much better for such material (see GIF).
JPEGs Are Lossy
Using discrete cosine transform, JPEG is a lossy compression method, wherein some data from the original image is lost. It depends on the image, but ratios of 10:1 to 20:1 may provide little noticeable loss. The more the loss can be tolerated, the more the image can be compressed.
Compression is achieved by dividing the picture into tiny pixel blocks, which are halved over and over until the desired amount of compression is achieved. JPEGs can be created in software or hardware, the latter providing sufficient speed for real time, on-the-fly compression. C-Cube Microsystems introduced the first JPEG chip. See JPEG2000, JPE file and GIF.
File Extensions
JPEGs use the JPEG File Interchange Format (JFIF), and file extensions are .JPG or .JFF. M-JPEG and MPEG are variations of JPEG used for full-motion digital video (see MPEG). See graphics formats.
Saving JPEGs
At first glance, these two dialogs seem contradictory because the larger number means high quality in one and low quality in the other. Photoshop (top) uses a 1-to-12 scale for quality, while Epson (bottom) uses a percentage for the amount of compression. The more compression, the more loss in the result. Standard is the original JPEG format, while Optimized compresses more effectively. Progressive causes the image to display incrementally from top to bottom. Web users with slow connections see the image form on screen right away rather than wait for the entire file to download first.
 | Reproduced with permission from Computer Desktop Encyclopedia. Copyright (c) 1981-2008 The Computer Language Company Inc. All rights reserved. |
Additional Resources
- Lossless JPEG Rotator (exe)
- Digital photos can be made with different shot orientaton. To easily view these photos they will have to be rotated to the correct position. With Lossless JPEG Rotator you can do this easily, without loss in quality and in most cases automatically. Rotated photos keep their original date and time....
- Software downloads 2008-09-03
- SpeedRename (msi)
- SpeedRename lets you rename your photographs in bulk. You specify the name template, and let SpeedRename do the rest. You can even extract EXIF information to form part of the name. If you have JPEG and RAW photographs, SpeedRename will rename them both at the same time. To top it...
- Software downloads 2008-09-03
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- When Toshiba finally pulled the plug on HD DVD, nobody was quite sure what the next step for the company was going to be. Would it go back to making DVD players, or would it forget the tensions of the format war and release a Blu-ray player? Well, instead of...
- Product reviews 2008-09-02
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- Face Recognition Based On Overlapping DCT - Matlab source code. In the JPEG image compression algorithm, the input image is divided into 8-by-8 or 16-by-16 blocks, and the two-dimensional DCT is computed for each block. The DCT coefficients are then quantized, coded, and transmitted. The JPEG receiver (or JPEG file...
- Software downloads 2008-08-31
- myFolder (exe)
- myFolder by Fusion|Ace Enterprises allows you to change any folder's background to any custom designed image. Bitmap, JPEG ,PNG, and any other common image formats. Simply open the software select the folder and select the image and get a brand new folder. This version is the first release on CNET...
- Software downloads 2008-08-28
- CinemaForge (exe)
- CinemaForge is a video player, video converter, and download/upload utility. The player supports FLV and (H264) video formats like (MP4). The converter supports Ipod (MP4), Flash SWF, Flash FLV, Motion Pictures Group MPEG, Audio Video Interleaved AVI, Window Media Video WMV, Real Video RM, QuickTime MOV, MP3, Advanced Streaming Format...
- Software downloads 2008-08-21
- Smartparts SPX12 Digital Picture Frame
- There are only so many ways to make a digital picture frame stand out in a sea of off-brand, no-name manufacturers making cheap LCDs available to the masses. Wireless Web access is one, as is design and options for changing the frame to suit your decor. Smartparts went the ease-of-use...
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- ButterFly (zip)
- Butterfly is a enhanced version of FLY, code by C program that creates PNG, JPEG, WBMP, or GIF images. Using Thomas Boutell's gd graphics library with some enhanced functions for fast image creation, it provides a command-file interface for creating and modifying images. This version is the first release on...
- Software downloads 2008-08-15
- MasterSoft Multi Converter (msi)
- MasterSoft Multi Converter is a image conversion software with many additional features like batch conversion, gif animation features, printing features and many more. View, save and convert the file formats: bitmap (*.bmp), graphics interchange format (*.gif), joint photographic experts group file (*.jpg; *.jpeg), icon file (*.ico), portable network graphics file...
- Software downloads 2008-08-14
- JPicPuz (jar)
- JPicPuz is a java applet that creates a jigsaw puzzle out any JPeg image. It takes 4x3, 4x4, and 3x4 image ratios and makes 12 - 16 pieces jigsaw puzzles. A replay button makes a new puzzle. Place this on your website to offer people an opportunity to make a...
- Software downloads 2008-08-13
- ImageConverterPro (exe)
- ImageConverterPro is a powerful image processing application with more than three dozen graphical filters and operations that can be applied on images in batch mode. The program can convert, resize, watermark, annotate, add effects, touch-up and rename, hundreds of pictures in just one session. ImageConverterPro is designed to save time...
- Software downloads 2008-08-12
- PDF to Image 2009 (zip)
- PDF to Image 2009 is to convert PDF to PNG, JPEG, BMP, TIFF and PCX, output high quality image file, It is fast, affordable way to convert a lot of adobe PDF files to popular image format once, single or batch conversions are supported, providing a wide range of options...
- Software downloads 2008-08-07
- Photo Sorter Platinum (exe)
- Photo Sorter will sort photos of all types (jpg, jpeg, and bmp) automatically. Sort photos easily with such photo sorter as Photo Sorter Platinum. This full-automatic photo sorter sort photos at any location - photos, pictures, images, and photographies of any type will be sorted according to your preferences, sort...
- Software downloads 2008-08-04
- Free Word/Doc Txt to Image Jpg/Jpeg Bmp Tiff Png (exe)
- Free Word/Doc Txt to Image Jpg/Jpeg Bmp Tiff Png Converter is a versatile converting tool, which can help you convert different document formats to image in batches once with ease. It has cool and professional style interface. It supports converting so comprehensive documents including Microsoft office word(.doc, docx. docm), rtf,...
- Software downloads 2008-08-04
- AutoDWG DWG to Image Converter Pro (exe)
- AutoDWG DWG to Image Converter featured with batch converting, easy to use wizard, converting many DWG and DXF files to JPG JPEG, TIF TIFF, GIF, PNG, BMP in one go. AutoCAD not required.Supports AutoCAD 2009. Pro version supports command line. You may set the Image Size, Output Color (True Colors,Gray...
- Software downloads 2008-08-04
- PDF Image Stamp COM Component (zip)
- PDF Image Stamp software automates the process of applying JPEG Images to different sized pdf's PDF Image stamp contains many special features like starting from any page, 1 in nth pages, x,y positioning on the page, image size scaling, image opacity, flip horizontal page, flip vertical page, alignment (centre, left,...
- Software downloads 2008-08-04
- Screen Capture Utility (msi)
- Allows you to peform full screen capture using hot keys + . Get rectangle screen capture together with selected window size by pressing + . Save to GIF, JPEG or BMP is very easy way. Copy image to clipboard. This version is the first release on CNET Download.com.
- Software downloads 2008-08-04
- Nikon D3 (body only)
- Photos:Nikon D3For years, Nikon users had been asking their favored camera maker for a dSLR with a full-frame sensor (the same size as a 35mm frame of film). Finally, Nikon caved, delivering the 12-megapixel D3; the result is a camera that reaches new heights in imaging with extremely low noise...
- Product reviews 2008-07-31
- Free PowerPoint/PPT to Image Jpg/Jpeg Bmp Tiff Png (exe)
- Free PowerPoint/PPT to Image Jpg/Jpeg Bmp Tiff Png Converter is super and all-in-one solution for converting image format with ease. It supports converting different document formats including powerpoint (.ppt, .pptx, .pptm) to so comprehensive image formats in batches once. With the easy and simple interface the converting process is easy...
- Software downloads 2008-07-30
- Free Excel/Xls to Image Jpg/Jpeg Bmp Tiff Png Conv (exe)
- Free Excel/Xls to Image Jpg/Jpeg Bmp Tiff Png Converter can help you export image formats effortlessly. It allows you to effortlessly batch convert different document formats to image format once with high speed. It has easy-to-use style interface. It can create image formats from documents including excel (.xls, .xlsm, xlsx)...
- Software downloads 2008-07-30
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