===== Image settings =====

In the image settings section image compression and tile related values can be configured.

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==== Image settings ====

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^ Field ^ Description ^
| Tile size | The size of each side of the served tiles in pixels. A value of 400 indicates that resulting tiles will be 400 x 400 pixels in size |
| Image format | The image format for all the served images (tiles, thumbnails, snapshots etc.). This can be JPEG ([[https://en.wikipedia.org/wiki/Lossy_compression|lossy compression]]) or PNG ([[https://en.wikipedia.org/wiki/Lossless_compression|lossless compression]]) |
| Tile quality | A value in the 1 to 100 range. This number defines the image quality for lossy compression schemes. Default value is 100 (equal to 100% quality). The parameter does //not// apply when the image format is set to PNG. [[impact_of_tile_quality_on_data_traffic|See what impact this has on data traffic]]. |

Don't forget to press the "Save" button before navigating away from this page.
==== Cache settings ====

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In the cache settings section the cache strategy of the system can be defined.

The learn more about what kind of data is cached in general, see [[caching|this page]].

^ Field	^ Description ^
| Use cache | Indicates whether or not the system caches requested tiles. By default, caching is turned off. |
| Cache path | The directory where cache files are stored. This is a web application relative path |
| Retention days | The number of days after which a cache file is automatically erased by the system | 
| Tile cache | Indication of current space consumption of cached tiles |
| S3 cache | Indication of current space consumption of cached chunks of slides that reside on S3 storage |
| Total cache size | Accumulated cache space consumption |

=== Operations ===

^ Operation ^ Description ^
| Empty cache older than retention days | Erase cache files that haven't been consulted recently |
| Empty cache for orphan slides | Erases cache files for slides that do not exist anymore |
| Empty all cache | Erases all cache files |
| Save | Saves the cache settings |

Don't forget to press the "Save" button before navigating away from this page.

==== Barcode settings ====
Settings about barcode recognition by PMA.core. This is an algorithm converting barcode images to text
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^ Field ^ Description ^
| Try harder to read barcode texts | Allow for more time consuming algorithms to read the barcodes. This can slow the system down but provide more accurate results |
| Disable barcode scanning | Disable barcode scanning completely for speed. You can disable this safely if you don't want the barcodes to be read in text  |