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I have been working through trying to get the NOAA ridge radar image to act as an overlay. Looking at other entries on the site I have worked with the image and have it projecting correctly but the png has a semi opaque white background I can't seems to get rid of.

I have tried setting transparent = true

it appears that the warp is adding the white background

gdalwarp -t_srs '+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs' radartemp1.png radartemp2.png

i tried also adding -dstalpha but then the layer comes out black...

anyone know how to solve this problem

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Which "site" are you referring to? – whuber Jun 16 '12 at 12:27
this I have searched the site for answers but have come up stumped on this background issue. and also Google etc. – MB. Jun 16 '12 at 16:04

Ok this was due to the fact that I had not used the correct projection should have been projection: "EPSG:3857"

Answered here.

Can't display overlay

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