Hello,
I continue to have problems with making no data values in a source Geotiff transparent. I have tried 1. using a SLD to implement this functionality, and I have also 2. assigned the value of 'InputTransparentColor' to '000000'. The following processing steps are relevant:
I made sure to set the alpha channel on the image using gdalwarp:
gdalwarp -s_srs epsg:4326 -t_srs epsg:4326 -srcnodata 0 -dstalpha pm25_NOGEO.tif pm25_GEO.tif
I also used the following SLD definition:
<?xml version="1.0" encoding="UTF-8"?>
<StyledLayerDescriptor xmlns="http://www.opengis.net/sld" xmlns:ogc="http://www.opengis.net/ogc" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.opengis.net/sld
http://schemas.opengis.net/sld/1.0.0/StyledLayerDescriptor.xsd" version="1.0.0">
<UserLayer>
<Name>raster_layer</Name>
<UserStyle>
<Name>PM 2.5</Name>
<Title>PM 2.5 Layers</Title>
<Abstract>Color Scheme for PM 2.5 Rasters</Abstract>
<FeatureTypeStyle>
<FeatureTypeName>Feature</FeatureTypeName>
<Rule>
<RasterSymbolizer>
<ColorMap>
<ColorMapEntry color="#fafafa" opacity="0.0" quantity="0.0" />
<ColorMapEntry color="#fafafa" opacity="0.5" quantity="1.0" />
<ColorMapEntry color="#fa0808" opacity="0.5" quantity="100.0" />
</ColorMap>
</RasterSymbolizer>
</Rule>
</FeatureTypeStyle>
</UserStyle>
</UserLayer>
</StyledLayerDescriptor>
In neither case do these steps work. I continue to get a black background.....
I would appreciate any help someone might offer...
Thanks, Bill