For example, a hillshade grid with cell values of 0 to 255, which then has NoData added to it, will be represented as unsigned 16 bit in order to store a value that is not being used to represent a valid value, such as 256. When NoData is added to a file-based raster that already has a full-bit range (meaning that all the values in the bit range, for example, 0 to 255, are all represented by at least one cell), it will be promoted to the next higher bit depth. The bit mask will be read, and NoData areas will be extracted at the time of retrieval. In geodatabases, if the original raster data contains NoData cells, a bit mask will be generated when loading the raster, and it will be stored in the database. For example, -9999 is a common value for storing NoData. NoData is stored as a mask that is part of the raster dataset, or using a pixel value in the dataset that is not used as a valid value elsewhere in the dataset.
A value must be estimated, and NoData cannot be returned.NoData is ignored, and a value is computed using any available values.Raster Calculator isnt one of them - when looking at a cell stack (ie same pixel in however many rasters) and performing a math operation on said stack, if any one of the cells is nodata, the result is nodata. NoData can be returned for the location no matter what Nodata (or null) in rasters is treated one of three ways.Some tools allow you to ignore nodata cells.When performing operations on raster data containing NoData values, there are typically three ways that NoData is treated for each cell: When calculating the statistics for a raster dataset, you can choose to ignore any cells with NoData. The image on the left shows a NoData area with a black background, and the image on the right shows that same area using no color. The fastest way to convert NoData value to 0 in ArcGIS is to use map algebra with the Con operator Con(IsNull(yourraster), O, yourraster) Now if you want to avoid creating those NoData values when you extract some values and there is no simple conversion rule, you can use the 'reclassify tool' making sure that you have an output value (which. When displaying rasters with NoData values, all renderers allow you to set the NoData value to a color or no color however, the Stretched renderer allows you to identify a specific background value and display color or no color.
Sometimes these are expressed as NoData values, although other times they may have real values. These can include borders, backgrounds, or other data considered to not have valid values. Sometimes there are homogeneous areas in a raster dataset that the you do not want to display. Cells can also have a NoData value to represent the absence of data. Cell values can be either positive or negative, integer, or floating point.
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