IMERGE

Merge images


EnvironmentsPYTHON :: EASI :: MODELER
Batch ModeYes
Quick linksDescription :: Parameters :: Parameter descriptions :: Details

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Description


IMERGE automatically merges a set of geocoded images or digital elevation model (DEM) files into a single image or DEM file. You can, optionally, specify a different projection for the output data.
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Parameters


Name Type Length Value range
Input: Input image layer(s) Raster port -   1 - 4096
Output: Output raster channel Raster port 0 - 1  
Projection for Output Merged Layer String 0 - 1 LONG/LAT, SPAF, SPCS, SPIF, UPS, UTM
Projection Zone Integer 0 - 1  
Projection Row (A - Z) String 0 - 1 A - Z
Model to Define the Shape of the Earth String 0 - 1  
Longitude or Latitude Image Bounds String 0 - 1 Y, N
Default: Y
Up Left (Longitude or Easting) String 0 - 1  
Up Left (Latitude or Northing) String 0 - 1  
Low Right (Longitude or Easting) String 0 - 1  
Low Right (Latitude or Northing) String 0 - 1  
Horizontal Pixel Size String 0 - 1  
Vertical Pixel Size String 0 - 1  
Non-Image Background Value for Input/Output Float 0 - 1  
Resample Mode String 0 - 1 NEAR, BILIN, CUBIC
Default: NEAR
Text file with Control Information for Merging String 0 - 1  
FOPTIONS String 0 - 1  
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Parameter descriptions

Input: Input image layer(s)

Specifies the input layers to be merged.

Output: Output raster channel

Specifies the output channel to receive the merged image data. The default value is 1; if DBOC (Output) does not exist, IMERGE adds a new channel and automatically sets the value of DBOC (Output) to the index of the newly created channel.

Projection for Output Merged Layer

Specifies the projection of the output file. If not specified, uses the map projection from the input files.

Supported projections include:

Projection Zone

If the projection is equal to UTM or State Plane, specifies the zone number of the output projection; otherwise, this parameter is not used.

Projection Row (A - Z)

If the projection is equal to UTM or UPS, specifies the row number for the projection; otherwise, this parameter is not used.

Acceptable values for this parameter are A through Z.

Model to Define the Shape of the Earth

Specifies the output ellipsoid or datum code to use to define the shape of the Earth. If defaulted, the earth model from the input files is used.

For a detailed list of supported ellipsoids, see the Projections reference section.

Longitude or Latitude Image Bounds

Specifies whether the bounds are longitude and latitude coordinates. If they are, set this parameter as Y or y (for YES). This is the default value.

If they are projection meters or feet, set as N or n.

Up Left (Longitude or Easting)

Specifies the X (horizontal) bound of the upper left corner of the output image. If not specified, the minimum X coordinate from the input files is used.

Up Left (Latitude or Northing)

Specifies the Y (vertical) bound of the upper left corner of the output image. If not specified, the maximum Y coordinate from the input files is used.

Low Right (Longitude or Easting)

Specifies the X (horizontal bound of the lower right corner of the output image. If not specified, the maximum X coordinate from the input files is used.

Low Right (Latitude or Northing)

Specifies the Y (vertical) bound of the lower right corner of the output image. If not specified, the minimum Y coordinate from the input files is used.

Horizontal Pixel Size

Specifies the horizontal pixel size of the output image. If defaulted, uses the minimum horizontal pixel size from the input files.

Vertical Pixel Size

Specifies the vertical pixel size of the output image. If defaulted, uses the minimum vertical pixel size from the input files.

Non-Image Background Value for Input/Output

Specifies the background value of the input image channel.

Pixels having the specified background value are interpreted as non-image values and are not transferred to the output file; this ensures that the output image contains only valid data from the input images.

If defaulted, the background value is zero (0).

Resample Mode

Specifies the resampling method to use for the output image.

Supported resampling methods include:

Text file with Control Information for Merging

Specifies the name of the text file containing information for merging the input files. If this parameter is not specified, no text file is read from or written to. If this parameter is specified and exists, the steps in the file are used when IMERGE is run, and the steps followed are recorded in the file before IMERGE exits. In addition to acting as a processing log for IMERGE, this parameter is a means of controlling IMERGE.

The text file specified by TFILE consists of several records. Each record starts with the record identifier of four or more characters. (Any characters after the fourth character are not used, but may be present. The characters may be lower- or upper-case.) Other fields on the record are separated by one or more spaces. Commas may also be used as field separators. Each record may be up to 132 characters and is terminated by the Return key (or the Enter key).

The order of the FILE records specifies the order of processing, but the order of any other records in the text file does not matter. Any LONG/LAT values are specified either as degrees, minutes, seconds, and hemisphere, with no spaces or commas separating the subfields, or as decimal degrees.

The TFILE records are as follows:

FOPTIONS

Specifies the options for creating the output file. These are specific to the file format, and in each case a no-option default is allowed. FOPTIONS can be used to specify the compression schemes, file format subtype, or other information.

For example, FOPTIONS="LZW", which means to use a Lempel-Ziv Welch compression.

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Details

IMERGE automatically merges a set of geocoded images or digital elevation model (DEM) files into a single image or DEM file. This function is most commonly used to merge DEM files.

The area of interest to use for the output image can be specified (ULX, ULY, LRX, LRY); otherwise, the maximum bounds of the input image files are used.

LLBOUND specifies whether ULX, ULY, LRX, and LRY are longitude and latitude values (LLBOUND="Y") or output projection units (LLBOUND="N").

The pixel resolution for the output image can be specified (BXPXSZ, BYPXSZ); otherwise, the minimum pixel resolution from the input files is used.

If ELLIPS is defined, it takes precedence over any ellipsoid defined in the PROJECT parameter.

Note: This algorithm is available only in canvas mode.

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