7

I'm doing some tests with QField at the request of the company I work for.

I was wondering what is the best (most efficient and practical) raster format with regard to the fluidity and the loading speed while using the app on-the-field ?

6

The QField documentation recommends using GeoPackage raster for this purpose.

Other sources (citation needed) recommend mbtiles format.

Whatever you choose, here are a couple of things to consider:

  • Tiling tiled data sources allow for loading only parts of the data and not always reading the whole dataset while rendering.

  • Pyramids if pyramids are built, it's possible to render raster images much more efficient at small scale (zoomed out) because aggregated information is already available pre-calculated.

  • Compression to make files small enough to fit on a handheld device, consider turning on some sort of compression. Raster data, like any non-random imagery, can normally be compressed very well (jpeg, png, ...) and for visual purpose like you have here, there's not even a need for a loss-less compression.

Have a look at the above link that provide some hints how to prepare the data using gdal commands (many of them are also available as QGIS processing algorithms)

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy