IIPImage: Generating thumbnails of specific sizes

From National Gallery Research Wiki
Jump to navigation Jump to search

Example Synatax

Width Specific

  • iipimage-server-url?FIF=/Full/Pyramid/Path&SDS=0,90&CNT=1.0&WID=128&QLT=75&CVT=jpeg

Height Specific

  • iipimage-server-url?FIF=/Full/Pyramid/Path&SDS=0,90&CNT=1.0&HEI=128&QLT=75&CVT=jpeg

Minimal Details

  • iipimage-server-url?FIF=/Full/Pyramid/Path&WID=128&CVT=jpeg
  • iipimage-server-url?FIF=/Full/Pyramid/Path&HEI=128&CVT=jpeg

Variables

The order of the GET variables included in the URL is important, feel free to try and experiment :-)

  • FIF: Absolute file path for the pyramidal image.
  • SDS: Sets the data object store. Optional value.
  • CNT: Contrast adjustment, basically a scale value for the value of each pixel. Try decreasing or increasing this values by multiples of 0.1 to see the effect. Optional value. Please note that if you are working with 16-bit images the CNT value is used to scale an 8-bit derivative, for a full range 16-bit image you will probably want to start with a CNT value of about 0.004.
  • WID or HEI: Defined pixel dimension of the generated image, at the time of writing the specific dimension of the resultant image will be 1 below the defined number. I assume that this is a result of rounding issues or it may be related to the fact that many numerical systems within programming begin with 0 rather than 1. The maximum possible pixel dimension (width or height) irrespective of which variable is defined can be limited using the MAX_CVT server variable, see website for more details.
  • QLT: Jpeg compression quality. A default value can be set for this using the JPEG_QUALITY server variable, see website for more details. Optional value.
  • CVT: This lets the server know that you require a single full version of the image.

Notes

  • Please note in the examples given below the &.jpg suffix at the end of some of the address within the MediaWiki syntax is not needed by IIPImage, it is just required to ensure that MediaWiki treats it like a normal external image.

Examples

256px wide 256px high 128px wide 128px high 64px wide 64px high
N-1093-00-000328-PYR.tif&SDS=0,90&CNT=1.0&WID=256&QLT=75&CVT=jpeg&.jpg N-1093-00-000328-PYR.tif&SDS=0,90&CNT=1.0&HEI=256&QLT=75&CVT=jpeg&.jpg N-1093-00-000328-PYR.tif&SDS=0,90&CNT=1.0&WID=128&QLT=75&CVT=jpeg&.jpg N-1093-00-000328-PYR.tif&SDS=0,90&CNT=1.0&HEI=128&QLT=75&CVT=jpeg&.jpg N-1093-00-000328-PYR.tif&SDS=0,90&CNT=1.0&WID=64&QLT=75&CVT=jpeg&.jpg N-1093-00-000328-PYR.tif&SDS=0,90&CNT=1.0&HEI=64&QLT=75&CVT=jpeg&.jpg

Brightened Image Darkened Image Jpeg quality 100 Jpeg quality 10
N-1093-00-000328-PYR.tif&SDS=0,90&CNT=1.5&HEI=256&QLT=75&CVT=jpeg&.jpg N-1093-00-000328-PYR.tif&SDS=0,90&CNT=0.5&HEI=256&QLT=75&CVT=jpeg&.jpg N-1093-00-000328-PYR.tif&SDS=0,90&CNT=1.0&HEI=256&QLT=100&CVT=jpeg&.jpg N-1093-00-000328-PYR.tif&SDS=0,90&CNT=1.0&HEI=256&QLT=10&CVT=jpeg&.jpg

Related to page Dissemination_of_High_Resolution_Images.