Raster Editing Overview

Raster data editing is used to process, identify, export, and visually analyze raster layers such as imagery and DEM data. Common tools are available from the top Raster tab.

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Most raster tools require you to select the target raster layer in the layer list before running the operation.

Overview

In the current version, raster editing capabilities fall into three categories:

• Data processing: Process raster content through clip, mask, difference, composite, mosaic, and related operations.
• Identification and output: Identify and query cell values, then export results with specified parameters.
• Analysis and display: Create statistical charts and adjust raster display appearance without changing the source data.

Raster Tools

Common tools in the Raster tab include:

• Raster processing: Clip, mask, difference, composite, and mosaic.
• Cell identification: Read cell values and coordinate information at the clicked location.
• Export: Export a new raster by setting parameters such as coordinate system, extent, cell size, and compression method.
• Create chart / Update statistics: Generate statistical charts such as histograms and refresh statistical results.
• Resampling type: Switch between nearest neighbor interpolation and linear interpolation for display.
• Appearance adjustment: Opacity, brightness, contrast, Gamma, display quality, and related settings.

Raster Processing

Raster processing generates new raster result data. The source data usually remains unchanged. A typical workflow is:

1. Select the input raster. Some tools require multiple input layers.
2. Set processing parameters and the output path.
3. Run the processing tool and add the result to the current project.

Processing tools are suitable for scenarios such as:

• Keeping only an area of interest, using clip or mask.
• Comparing differences between two imagery periods, using difference.
• Combining multi-source imagery, using composite or mosaic.

For detailed parameters and examples, see Raster Data Processing and Operations.

Cell Identification

Definition

Cell identification queries the cell attributes at a location in raster data, based on a user click or input coordinates.

A cell is the smallest spatial unit in raster data. Each cell usually contains:

• Spatial position, such as row and column indices or geographic coordinates.
• Cell value, such as elevation, temperature, land-cover code, or index value.
• Optional additional information, such as NoData status, statistics, or band values.

Principle

Cell identification is essentially a spatial query. The core steps are:

1. Record the coordinates of the clicked point.
2. Use the raster georeferencing parameters to map the coordinates to row and column indices.
3. Read the cell value at that index.
4. Return the identification result, including coordinates, fields, cell value, and NoData status.

Export

Export generates a new output file from the current raster using specified parameters.

Parameter	Description
Output file name	User-defined name of the exported result.
Output path	Location where the exported file is saved.
Output format	The current interface supports TIFF by default.
Coordinate system	Spatial reference for the output data.
Output extent	Use the source data extent, use the extent of a specified layer, or manually set the four bounds.
Clip raster with vector	Use a vector extent as the clipping geometry.
Retain option	Keep either the inside or outside of the vector geometry.
Align bounds	Automatically adjust cell size and raster size so the result aligns with the specified extent.
Cell size	Output resolution in X and Y directions.
Raster size	Number of output columns and rows.
Pixel type	Output data type, such as 8U, 16S, or 32F.
NoData value	NoData value for the output raster.
Compression method	Supports LZW, PACKBITS, DEFLATE, LZMA, and ZSTD.
Compression quality	Controls quality when lossy compression is supported.

important

Export creates a new data file and does not overwrite the source raster. Before exporting, check whether the coordinate system, extent, and cell size meet your analysis requirements.

Raster Statistics

Raster statistics display the distribution of raster values in chart form. They are commonly used to quickly assess data range, dispersion, and distribution pattern.

A common workflow is:

1. Select a raster layer in the layer list.
2. Click Create chart.
3. In chart properties, choose parameters such as variable, transformation method, and number of bins.
4. View statistical results in the chart window, such as mean, median, standard deviation, maximum, and minimum.

For details, see Create Statistical Charts from Rasters.

Appearance Adjustment

Appearance adjustment optimizes display effects. It mainly affects visual rendering and does not change source raster cell values.

Common parameters include:

• Opacity
• Brightness
• Contrast
• Gamma
• Display quality
• Resampling type, such as nearest neighbor interpolation or linear interpolation

Applicable scenarios include:

• Improving basemap readability during overlay display.
• Enhancing imagery detail contrast to support visual interpretation.
• Quickly achieving a more suitable display effect without changing the data.