arcgis desktop - Selecting pixels in raster using polygon selection tool?

I want to reclassify landcover image manually with respect to online imagery. I am looking for a software/plugin/script to manually select raster pixels using polygon selection tool and could be able to enter new value.

I have Arcgis with spatial analyst license.

Answer

Edit your polygons to cover where you want to change the landcover raster, be sure to use the same pixel codes, for example if grass = 8 then make sure your grass polygons has a numeric field with a value of 8. It is also best for the vector to be in the same coordinate system as the raster.

Set your environments snap raster and extent to match your existing landcover raster and convert polygon to raster using the value field which matches the classes, be sure to use the same cell size as your existing raster, this will ensure your cells match exactly. Your polygon raster will now have values where the polygons are and everything else should be nodata.

Using the Raster Calculator use an expression like:

Con(IsNull(PolyRaster),OriginalLandCover,PolyRaster)

Substituting the values for your polygon raster and landcover raster, this will use original landcover where your polygons aren't (is null) and polygon raster where a value exists (is not null). The Con tool is a true/false decision tool, paired with IsNull which is true where the raster is NoData and false where it has a value.