Maps | Map search | Technological description | Back to home page

Maps in Map deposit are scanned in 600 dpi resolution with 24 bites colour depth at MoD Mapping Non-Profit Limited Company. On Internet versions reduced to 100 dpi are used that are compressed with MrSid encoder software of LizardTech Inc.

Reasons of this solution are the following:

• Publication of 600 dpi resolution pictures cannot be carried out on Internet (the size of one picture is hundreds megabites)
• Size of the pictures reduced to 100 dpi is still around 10 megabites.
• In case of using GIF format, compression is inadequate.
• In case of using JPG format lined and textual items become indistinct.

Because of the reasons above SID format has been chosen. This technology provides that pictures are enjoyable even in case of highly efficient compression. SID format pictures are accessible through MrSid Image Server which provides the view of pictures in three ways:

• JPG or BMP
  in this case user space is very poor but it can be used with any browsers or operational systems
• Java applet
  it provides perspecious user space, it downloads automatically at the first usage but it can be used only with browsers supporting java
• MrSid plug-in
  this solution provides the most comfortable user space. Pictures can be saved in more kinds of file formats and it also supports printing. But it can be used only with Microsoft Internet Explore and Netscape browsers. Using MSIE, plug-in downloads and installs automatically, using Netscape browser, plug-in can be downloaded from the website of LizardTec Inc. (Note: Problems may occur while using some versions of Netscape browsers)

If pictures are downloaded in SID format, a free SID viewer, which can re-write the pictures in TIFF format (it can be downloaded from the website of LizardTech Inc. ) Additions (ex. Adobe Photoshop, Microstation 95, etc.) can be downloaded to several softwares. Those provide direct read.