gdal_polygonize not converting raster values

Question

I am trying to convert a weather radar geoTIF to geoJSON using gdal_polygonize.

I am sharing the original .tif on google drive :
https://drive.google.com/file/d/1p2eE0QUtNypNjs5Qb9JBfXrDdMd8Ifpb/view?usp=sharing
My command to convert is :
python gdal_polygonize.py -q KEWX_L2_BREF_RAW_20210624_165114.tif -f "GeoJSON" myPolygonizedImage.geojson

It produces a file with lots of data that looks to be correct, but there is no information about the color values. Example of the output for a random polygon :
{ "type": "Feature", "properties": { }, "geometry": { "type": "Polygon", "coordinates": [ [ [ -95.429, 32.3965 ], [ -95.429, 32.394 ], [ -95.4265, 32.394 ], [ -95.4265, 32.3965 ], [ -95.429, 32.3965 ] ] ] } },

Is there a way to also have the script place color value data in the output? I am new to gdal_polygonize - maybe I am not understanding the basics? I am using GDAL 3.1.0, released 2020/05/03.

user30184 · Answer

As documented https://gdal.org/programs/gdal_polygonize.html gdal_polygonize should create an attribute.

This utility creates vector polygons for all connected regions of
pixels in the raster sharing a common pixel value. Each polygon is
created with an attribute indicating the pixel value of that polygon.

By default the field is named "DN"
I used your command with GDAL 3.1.4 installed with OSGeo4W installer on Windows
and I got a result that contains features with DN attribute
{ "type": "Feature", "properties": { "DN": 89 }, "geometry": { "type": "Polygon", "coordinates": [ [ [ -98.959, 33.4565 ], [ -98.959, 33.454 ], [ -98.9465, 33.454 ], [ -98.9465, 33.4565 ], [ -98.959, 33.4565 ] ] ] } },

I do not what goes wrong for you.

gdal_polygonize not converting raster values

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