4.1.4 Partial uncompressing of Pleiades images in Monteverdi

The next very important thing one can do with Monteverdi is to select an area of interest in the Pleiades image so as to uncompress it to disk. To do so, open the Pleiades dataset into the Uncompress Jpeg2000 image module from the File menu. Figure 4.5, page 182 shows what this module looks like. On the left, one can find informations about the images: dimensions, resolution level, and number of Jpeg2000 tiles in image, dimension of tiles, and size of tiles in mega-octets. The center part of the module is the most important one: it displays a quick-look of the Pleiades image. On this quick-look, one can select the area to be decoded by drawing a rectangle with the mouse. The red rectangle shown by the module corresponds to this user-defined area. On the left, in red, one can find the start index and size of corresponding region.

The module also displays a green rectangle, which shows the minimum set of tiles to be decoded to decode the red area: this is the region that will actually be decoded to disk. On the left, in green, one can find information about this region: how many tiles it contains, and what will be the size of the corresponding decoded output file.

Once one chose her area of interest, one can click on the Save button, and select an output file. The module will write a geometry file (with the .geom extension) with all useful metadata in it, so that when reading back the file in Monteverdi or in OTB Applications, geometry and radiometry based functionalities can still be used.


Figure 4.5: A Pleiades image in Monteverdi Uncompress Jpeg2000 image module. CNES 2012