AlgART HTML Packer (AHP)


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AlgART HTML Packer (AHP)

Компания SIAMS представила новую уникальную утилиту, позволяющую создавать самораспаковывающиеся HTML страницы и JavaScript программы, сжатые c использованием популярных алгоритмов Хаффмана и Лемпеля-Зива.

С помощью утилиты AlgART HTML Packer (AHP) вы можете значительно уменьшить время загрузки ваших web-страниц и сократить Интернет-трафик. AHP создает самораспаковывающиеся HTML страницы, распаковка которых производится с помощью небольшой JavaScript функции. Таким образом, для просмотра сжатых страниц пользователю не требуется никакого специального ПО кроме браузера c поддержкой JavaScript (IE 3.0-5.x, NN 3.0-4.x, Opera 3.51-3.6x, HotJava Browser 3.x).

Качество сжатия, получаемое с помощью AHP сравнимо с качеством сжатия, получаемым популярными архиваторами, такими как Arj, PKZip, Rar. Типичная HTML-страница может быть ужата в 1.5-5 раз, причем, чем больше размер страницы, чем сложней ее структура, тем лучше она сжимается. При этом скорость распаковки кода значительно выше, чем скорость загрузки страниц через Интернет. Для сравнения: самораспаковка, в зависимости от использованного алгоритма сжатия, происходит со скоростью 10-100 Кбайт в секунду на усредненном ПК с Pentium-200.

The new utility AlgART HTML Packer (AHP) allows You to compress HTML pages and embedded JavaScript code, by means of Lempel-Ziv and Huffman packing algorithms. So, You can reduce the time of loading your page and retrench Internet traffic, especially for large Web pages with 50-150 Kbytes of HTML or JavaScript text.

About AHP

AHP generates the compressed self-unpacking HTML page, which is equivalent to your source page, but has the smaller size. The unpacking is performed by means of several small JavaScript functions added at the beginning of the page.

The compression ratio given by AHP compares with the compression ratio of such popular archivers as PKZip, Arj, Rar: a typical HTML-page can be compressed by 1.5-5.0 times. Usually, the large pages can be packed better than small ones and the pages with complex HTML structure and many HTML tags can be packed better than the simple ones.

The unpacking speed is greater than the speed of loading the same data through Internet for most situations: the self-unpacking code unpacks 10-100 Kbytes per second on Pentium-200.

The built-in unpacking functions don't require any software installed on the client computer except the Web-browser: they are written on the minimal version of JavaScript, which is supported by the most of browsers. The unpacking functions were tested under Microsoft Internet Explorer 3.0-5.0, Netscape Navigator 3.0-4.5, Opera 3.51-3.60, HotJava Browser 3.0 (Windows platform).

AHP is implemented as HTML- or ASP-page by means of JavaScript. No components such as COM, ActiveX, Plug-Ins, Java-applets are used. So, this utility is more portable and safe to install and use than usual applications.

AHP is used in following Web-sites:

www.midural.ru - official server of Sverdlovsk region (Russia);

www.sov.mplik.ru - official server of Ekaterinburg city, the administrative centre of Sverdlovsk region.

The delivery package

We offer AlgART HTML Packer in 2 editions: user and professional.

The user edition of AHP comprises:

The client-side utility ahp.htm, which allows the easy packing of your HTML-page, the fragment of HTML-page, JavaScript code or any text data used from JavaScript. This utility is a Web page; it requires Microsoft Internet Explorer 4.0+ or Netscape Navigator 4.0+ to work.

On-line help for this utility.

This edition is intended to be used by Web-designers and any other users, who write HTML pages. It is very easy to use and doesn't require high qualification.

The professional edition of AHP also includes:

The server-side version of the packing utility ahp.asp; this utility must be placed into your ASP-server and can be used with any browser.

The JavaScript server-side ASP library apack.js.asp with built-in documentation, designed for professional JavaScript programmers, with complete set of functions for packing and unpacking text data. It allows You to design your own packing solutions.

This edition is designed for Web-programmers, developers of large Web-sites or information servers.

Requirements

The user edition of AHP (ahp.htm) requires Microsoft Internet Explorer 4.0+ or Netscape Navigator 4.0+.

The professional edition of AHP (ahp.asp and ASP-library apack.js.asp) requires ASP-server, which completely supports JavaScript 3.0+ (in Microsoft terms) on the Web-server. For example, AHP will work under Microsoft Internet Information Server 4.0+. On the client computers, You can use any Web-browser.

The unpacking algorithm embedded in the Web pages built by using AHP doesn't require any software installed on the client computer except the Web-browser which supports JavaScript (such as Microsoft Internet Explorer or Netscape Navigator).

In any case, we recommend to run AHP under Microsoft Internet Explorer 4.0+: it works faster, and You can pack large HTML texts at a go - many other browsers cannot place >30000 characters in 1 text input box (textarea).