In order to improve the browsing and access efficiency of the image service, the dynamic cache scheme can be enabled. After the scheme is enabled, the existing Tile resources under the cache directory will be directly loaded when the front-end browses the Image Map. If no available Tile is found, the image will be dynamically plotted.

The existing Tile resources in the cache directory come from the following two ways:

• First, enable dynamic cache. When the front-end browses Image Map, the result tile of dynamic plotting will be stored in the cache directory.
• Second, enable silent slicing and pre-generate image map tiles in the cache directory.

Cache directory

The default cache directory path of the image service: installation directory \webapps\iserver\output\"Image Service Name"\. The folder named "Image Collection Name" under this directory stores the tile of the corresponding collection.

The image service cache directory can be modified as follows:

1. Enter the service management page and click "Service Provider", as shown in the following figure.

2. Expand "Advance Settings", where the tile storage path is the cache directory; Tile storage type: supports raw, compact, and MongoDB.

3. After completing the configuration, click the "Save" button to make the configuration effective.

Dynamic cache tiles and silent slice tiles of all image collections in the image service share the cache directory (tile storage path) and tile storage type configuration described above.

Turn on dynamic caching

1. Enter the management page of the image service, as shown in the following figure.

2. Click the target collection name to enter the collection configuration page.

3. Switch to the "Tile Cache Config" page and turn on "CacheEnable".

After the dynamic cache is enabled, the dynamically generated tile will be cached when browsing the image data of the set. When browsing the image again, the tile under the cache directory will be reused to improve the response efficiency. If this item is not enabled, the dynamically generated tile will not be cached.

Configuring the Dynamic Cache Tile Scheme

To configure the tile scheme for dynamic plotting, proceed to the "TileCacheConfig" page to complete the following parameters:

• Accessible Level Range: Limit the tile level range that can be requested by the front-end. If the request exceeds this range, the tile will not be accessed. The level, row and column numbers of

  the tile are divided by the global rule. Based on the global of the image ccollection coordinate system, the X index (column number) starts from the top left corner of the global. The index number is 0 and increases from left to right; The Y index (row number) starts from the top left corner of global, the index number is 0, and increases from top to bottom; the Z index (level) starts from 0, and the corresponding scale bar is: 1:591658710.9091.

• Tile Format: The picture type of the tile.
• Tile Size: 256 * 256 pixels.
• DPI：96。
• Transparent: Is on, indicating Tile Background Transparency.

The tile scheme is configured in the image collection, and different collections in the service can be configured with different tile schemes.

Dynamic cache tile and silent slice tile for imaging services, share this tile scheme configuration.

Save the configuration

After Completing the configuration, click the "Add" button to make the configuration effective.

Note: Currently, the result Tile of dynamic plotting does not support caching to the MongoDB database.