>- on initial load of a raster, generate a quicklook that is the larger >of 1/4 screen resolution or 500x500 pixels by sampling every nth pixel >- generate a histogram from the quicklook >- calculate clipped 2% - 96% range min max for each band >- apply a histogram stretch based on the above >- the histogram could be used for generating the graph in raster >props, and the quicklook could be used to create thumbs and previews >etc >- ideally we should cache these quicklooks and only regenerate them if >the underlying dataset has changed > >I believe if we do this we will have fast initial load and the images >(grayscale and rgb) will 'look right' when first loaded (i.e with good >contrast) and it would not be necessary to assign any color value to >grayscales by default. > >Regards
Hi, just my 2 ct. I guess the more important capability with raster is to open they faster possible. I fear calculate all these values on first opened take more time than what is waitable for the open of a raster. Perhaps this action should be choosable by settings ? Of course I see our situation. Our situation is of more sets of raster (7-800 each set) where every raster is grey level or true color of 3-400 Mbyte each. And all these raster are accessible by a remote shared server to our users. For a total, actually, of about 13.000 rasters. I don't understand if this new feature could be really usable in a situation like our. -- ----------------- Andrea Peri . . . . . . . . . qwerty àèìòù -----------------
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