| SAEC_/_Kinetic_Vision_-_Design_Visualization Offering 3D Studio MAX network render and videotape transfer services. Please contact for more information. |
| American_Design_Drafting_Association The ADDA is an individual membership society for the design drafting community across all industries. |
| CAD_Society A not-for-profit organization which has the goal of encouraging open communication among those in the CAD industry. |
| Enter An open source Enterprise 128 emulator for Windows. |
| Enterprise_64/128_Depository Enterprise 64/128 depository and Emulator Project. |
| EPTE Enterprise Tape Emulator. EPTE is a free virtual tape recorder for the Enterprise 128k home computer. |
| Zilog_Realms EP32 an open source 128 emulator for Windows based on Kevin Thackers "enter" emulator, and a small collection of demos and programs. |
| Bioeddie\'s_Psion_emulators Various emulators for Psion. |
| pocketemulator_com Emulators for Pocket PC. |
| Adobe_Systems Adobe Type Library offers a collection of quality fonts from internationally renowned foundries, as well as individual type designers and distinguished design studios. |
| Agfa_Monotype_Corporation Purchase libraries of typefaces from designers, and independent foundries. Also offers custom font design and font technology development. |
| Altemus_Collection Thousands of decorative and dingbat designs, fonts for Mac and PC. Over 50 unique fonts; stars, bursts, borders, sports, and spirals printers cuts. |
| Berthold_Font_Store A source of high-quality fonts for design professionals and other font users available for immediate purchase and download. |
| BuyFonts Vendor of TrueType and PostScript fonts, including Braille, OCR, bar codes, phonetic, mathematical, and symbolic fonts. |
| Chank The Chank Company manufactures and distributes a large selection of freeware and commercial fonts by type designers from all over the world. |
| Download-fonts_com Download mac fonts and windows fonts. Browse and download truetype fonts and postscript fonts. |
| Educational_Fontware,_Inc Handwriting fonts for teachers and homeschoolers. Very comprehensive list, many variations (dotted, outlines, arrows, rules) of each family (D'Nealian, Zaner-Bloser, Getty Dubay). |
| Faces Offers fonts from a number of foundries, royalty free photographs, picture fonts and clip art for download or on CD. |
| Font_Technology_-_Bitstream Bitstream is the leading developer of font technology, digital fonts, and custom typeface designs for a wide variety of markets. |
| Font_Works_Digital_Retail UK's principal font supplier representing over 100 foundries worldwide, |
| Fonts4eva Free and for-sale fonts and software which you can purchase to make your own fonts. |
| FontShop Offers font search by name, designer or foundry. Also provides custom creation and conversions, Font Feed, blog and magazine. |
| GraphicObsession Royalty free images, footage and fonts. Search, compare, test, purchase and download thousands of images and fonts. |
| Graphx_Edge Windows TrueType downloadable font collections includes script fonts, headline, unique and dingbat fonts. |
| ITC_Fonts The site of the International Typeface Corporation. A comprehensive typeface library,up-to-date and accurate information on new fonts, and an interactive online typesetter to view fonts with. A lot of |
| Kanecal Offers symbols used in drafting/blueprint callouts. Geometric Dimensioning and Tolerancing (GD&T) symbols (with Feature Control Frames) plus Statistical Process Control (SPC) symbols. Barcodes for |
| MICR_Encoding_Fonts__com Distributors of MICR E-13B and CMC-7 fonts for bank check printing. Fonts are available as PostScript, TrueType and PCL for Windows, Macintosh and UNIX. |
| MyFonts E-commerce offering a variety of choices, as well as an area to upload images. Includes information about designers and foundries. |
| Nextag_com-_Fonts_Software Several font collections on CDs |
| Phil\'s_Fonts Source for type and graphic software. Distributor of Postscript and TrueType fonts, from more than 75 foundries around the world also specializes in creating custom fonts. |
| School_Fonts Font sets compatible with the D'Nealian, and Zaner-Bloser methods of learning handwriting. Offers, cursive handwriting, Block letters, and kindergarten dingbats. Exercise sheets, free samples and comp |
| Terrapin_Solutions_Limited UK based company supplies typefaces from all of the major font manufacturers as well as a range of more modern and experimental designs from around the world. Language fonts, bar code and OCR fonts ar |
| Typos_Type_&_Image_Design Provides fonts, typographic and corporate identity services, updates and licensing. |
| ACE_32 The Jupiter ACE Emulator for MSDOS |
| Spectravideo_software_tools Support site for the SVI-318/328 emulator by Jimmy Mårdell. Features a cas to wave and wave to cas converter, a frontend, and a manager for the cassette files. |
| SVI-318/328_emulator An open source SVI-318/328 emulator for DOS. |
| FLEX-ES System/390 on Intel-based servers. |
| IBM_7094_Emulator An open source IBM 7094 series emulator for Windows written in Delphi. |
| IBM_Mainframe_Computer_Time_to_Rent Systems include OS/390, VM/ESA, and VSE/ESA. |
| s709_-_IBM_709/7090/7094_emulator An open source IBM 709/7090/7094 emulator for Windows. |
PSNR = 20 * log10 (255 / sqrt(MSE)) where I(x,y) is the original image, I'(x,y) is the approximated version (which is actually the decompressed image) and M,N are the dimensions of the images. A lower value for MSE means lesser error, and as seen from the inverse relation between the MSE and PSNR, this translates to a high value of PSNR. Logically, a higher value of PSNR is good because it means that the ratio of Signal to Noise is higher. Here, the 'signal' is the original image, and the 'noise' is the error in reconstruction. So, if you find a compression scheme having a lower MSE (and a high PSNR), you can recognise that it is a better one. The Outline We'll take a close look at compressing grey scale images. The algorithms explained can be easily extended to colour images, either by processing each of the colour planes separately, or by transforming the image from RGB representation to other convenient representations like YUV in which the processing is much easier. The usual steps involved in compressing an image are Specifying the Rate (bits available) and Distortion (tolerable error) parameters for the target image. Dividing the image data into various classes, based on their importance. Dividing the available bit budget among these classes, such that the distortion is a minimum. Quantize each class separately using the bit allocation information derived in step 3. Encode each class separately using an entropy coder and write to the file. Remember, this is how 'most' image compression techniques work. But there are exceptions. One example is the Fractal Image Compression technique, where possible self similarity within the image is identified and used to reduce the amount of data required to reproduce the image. Traditionally these methods have been time consuming, but some latest methods promise to speed up the process. Literature regarding fractal image compression can be found at <findout>. Reconstructing the image from the compressed data is usually a faster process than compression. The steps involved are Read in the quantized data from the file, using an entropy decoder. (reverse of step 5). Dequantize the data. (reverse of step 4). Rebuild the image. (reverse of step 2). Details Details about classifying image data (using the Discrete Wavelet Transform). Details about bit allocation (using the Rate-Distortion optimization procedure). Details about quantization. Details about entropy coding. Some interesting sites Fractal Image Encoding at http://inls.ucsd.edu/y/Fractals/ . Contains a real LOT of interesting papers and software related to Fractal image encoding. Compression newsgroup at comp.compression Wavelet Image Compression Kit at http://www.geoffdavis.net/dartmouth/wavelet/wavelet.html Image Compression at http://www.iee.et.tu-dresden.de/~franz/image1.html 
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