Requirement specification for large amounts of imagery data

Format

The submitted image data should consist of uncompressed TIFF images without image pyramids. Images in compressed formats such as JPEG, ECW, MrSID and JP2000 cannot be edited and may therefore be denied dissemination permit.

Multispectral image information

For material containing both color (RGB) and near-infrared (NIR) imagery, we prefer that you submit merged four-band imagery (RGB+NIR) rather than two separate files (RGB+CIR). Separate files take up more storage space and result in extra workload during processing.

Aerial imagery

Consider the following before submitting the material for review. The submitted imagery should be radiometrically corrected. If you use an aerial camera that has one or more high-resolution panchromatic sensors and/or multiple color information sensors such as the Vexcel's UltraCam series. The imagery should be PAN-sharpened before submission. Unsharpened RGB images with associated PAN images take up more storage space and result in extra workload during processing.

For each aerial image, there should be a polygon showing the full extent of the image on the ground. Each polygon should have an attribute with the file name of the aerial image. If the files do not have unique names, the full path to each file should also be included in the file name. All polygons should be delivered as an ESRI shape file.

If there are multiple images from the same exposure or multiple images with the same file name, each such image should have its own polygon. For example, one polygon for a RGB image and one polygon for a CIR image.

Refined products such as orthophotos, 3D models and surface models should be generated from the already approved material. In that case, these products do not need to be submitted for dissemination approval unless otherwise stated in the decision.

Orthophoto

Do not apply for a dissemination permit for orthophotos if you intend to apply for and disseminate the underlying aerial imagery. If you apply for both, it leads to longer processing times. Instead, generate orthophotos from the returned aerial imagery after these have been approved for dissemination.

If the depicted area covers a larger area (>10 km²) or if each image is larger than 4 GB (uncompressed), the data set should be divided into smaller non-overlapping boxes, so-called tiles.

Orthophotos should be georeferenced using TFW and PRJ files, alternatively the material should be sent in GeoTIFF format. If georeferencing is missing, a footprint for each included TIFF file should be sent in the form of polygons in an ESRI shape file with the image filename as an attribute. Don't forget to include associated PRJ files.

Other

If you are going to apply for a dissemination permit for several projects, you should apply for each project separately. The material for each project/case should be placed on separate storage devices such as USB flash drives or external hard drives. Each storage unit should be marked with the case number. If you submit material for multiple cases on the same storage device, all material will be returned when the last case has been processed.

Only send the material for which you want to obtain a dissemination permit. Data that is not to be disseminated should not be included in the delivery.

For conceptual explanations, see HMK Glossary (pdf, opens in new window)