Merge pull request #19 from stac-extensions/nodatavalues

Add "inf" and "nan" as valid nodata values

Author: emmanuelmathot

CHANGELOG.md

@@ -8,6 +8,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- Allow "inf" and "nan" as valid nodata values [#18](https://github.com/stac-extensions/raster/issues/18)
+
 ### Changed
 
 ### Deprecated

README.md

@@ -35,7 +35,7 @@ to specify information about the raster projection, especially `proj:shape` to s
 
 | Field Name         | Type                                    | Description                                                                                                                                                                      |
 | ------------------ | --------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
-| nodata             | number                                  | Pixel values used to identify pixels that are nodata in the band .                                                                                                               |
+| nodata             | number | string                                  | Pixel values used to identify pixels that are nodata in the band either by the pixel value as a number or `nan`, `inf` or `-inf`.                                                                                                               |
 | sampling           | string                                  | One of `area` or `point`. Indicates whether a pixel value should be assumed to represent a sampling over the region of the pixel or a point sample at the center of the pixel.   |
 | data_type          | string                                  | The data type of the pixels in the band. One of the [data types as described above](#data-types).                                                                                |
 | bits_per_sample    | number                                  | The actual number of bits used for this band. Normally only present when the number of bits is non-standard for the `datatype`, such as when a 1 bit TIFF is represented as byte |

examples/item-sentinel2.json

@@ -562,6 +562,13 @@
           "full_width_half_max": 0.026
         }
       ],
+      "raster:bands": [
+        {
+          "data_type": "uint16",
+          "spatial_resolution": 60,
+          "nodata": "nan"
+        }
+      ],
       "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/B09.tif",
       "proj:shape": [
         1830,

json-schema/schema.json

@@ -132,7 +132,19 @@
           },
           "nodata": {
             "title": "No data pixel value",
-            "type": "number"
+            "oneOf": [
+              {
+                "type": "number"
+              },
+              {
+                "type": "string",
+                "enum": [
+                  "nan",
+                  "inf",
+                  "-inf"
+                ]
+              }
+            ]
           },
           "scale": {
             "title": "multiplicator factor of the pixel value to transform into the value",