Raster histogram
From AWF-Wiki
(Difference between revisions)
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# Click the {{button|text=Add raster layer}} [[Image:QGIS_2.0_addrast.png|20px]] and select the file ''C:/OSGeo4W64/geodata/raster/s2/Subset_S2A_MSIL2A_20170619T.tif''. | # Click the {{button|text=Add raster layer}} [[Image:QGIS_2.0_addrast.png|20px]] and select the file ''C:/OSGeo4W64/geodata/raster/s2/Subset_S2A_MSIL2A_20170619T.tif''. | ||
| − | # After clicking {{button|text=Open}}, the raster layer appears on the QGIS canvas. | + | # After clicking {{button|text=Open}} , the raster layer appears on the QGIS canvas. |
# Right click the layer name in the Layers panel and select {{mitem|text=Properties --> Histogramm}} | # Right click the layer name in the Layers panel and select {{mitem|text=Properties --> Histogramm}} | ||
This dialog displays a histogram for all bands band. Left click and drag a box on the diagram to zoom in. | This dialog displays a histogram for all bands band. Left click and drag a box on the diagram to zoom in. | ||
| − | + | Click on {{button|text=Pref/Actions}} and activate ''Draw as lines'' (Figure '''A'''). | |
| − | The value range of the | + | [[Qgis_histogram_multiband.png|thumb|left|800px|'''Figure A:''' Line histograms of all bands]] |
| + | Click on {{button|text=Pref/Actions}} and deactivate ''Draw as lines''. Activate ''Show selected band'' and ''Always show min/max markers''. | ||
| + | The value range of the selected band data is evenly divided into bins. The histogram shows how many pixels of the image fall into each of the bins (Figure '''B''')[[Qgis_histogram_singleband.png|thumb|left|800px|'''Figure B:''' Histogram of a single selected band]]. Click on [[Qgis_save_icon.png|100px]]. The graphics may be saved as png file. | ||
[[Category: Working with Raster Data]] | [[Category: Working with Raster Data]] | ||
Revision as of 20:18, 22 October 2017
- Click the Add raster layer
and select the file C:/OSGeo4W64/geodata/raster/s2/Subset_S2A_MSIL2A_20170619T.tif.
- After clicking Open , the raster layer appears on the QGIS canvas.
- Right click the layer name in the Layers panel and select Properties --> Histogramm
This dialog displays a histogram for all bands band. Left click and drag a box on the diagram to zoom in. Click on Pref/Actions and activate Draw as lines (Figure A). thumb|left|800px|Figure A: Line histograms of all bands Click on Pref/Actions and deactivate Draw as lines. Activate Show selected band and Always show min/max markers. The value range of the selected band data is evenly divided into bins. The histogram shows how many pixels of the image fall into each of the bins (Figure B)thumb|left|800px|Figure B: Histogram of a single selected band. Click on 100px. The graphics may be saved as png file.
