Routines (alphabetical) > Object Classes > File Format Object Classes > IDLffMrSID::GetProperty

# IDLffMrSID::GetProperty

Syntax | Arguments | Keywords | Examples | Version History

The IDLffMrSID::GetProperty function method is used to query properties associated with the MrSID image.

## Syntax

Obj->[IDLffMrSID::]GetProperty [, CHANNELS=nChannels] [, DIMENSIONS=Dims] [, LEVELS=Levels] [, PIXEL_TYPE=pixelType] [, TYPE=strType] [, GEO_VALID=geoValid] [, GEO_PROJTYPE=geoProjType] [, GEO_ORIGIN=geoOrigin] [, GEO_RESOLUTION=geoRes]

## Arguments

None

## Keywords

### CHANNELS

Set this keyword to a named variable that will contain the number of image bands. For RGB images this is 3, for grayscale it is 1.

### DIMENSIONS

Set this keyword equal to a named variable that will contain a two-element long integer array of the form [width, height] that specifies the dimensions of the MrSID image at level 0 (full resolution).

### GEO_ORIGIN

Set this keyword to a named variable that will contain a two-element double precision array of the form [x, y] that specifies the location of the center of the upper-left pixel.

### GEO_PROJTYPE

Set this keyword to a named variable that will contain an unsigned integer that specifies the geoTIFF projected coordinate system type code. For example, type code 32613 corresponds to PCS_WGS84_UTM_zone_13N.

For more information on the geoTIFF file type and available type codes see:

http://www.remotesensing.org/geotiff/geotiff.html

### GEO_RESOLUTION

Set this keyword to a named variable that will contain a two-element double precision array of the form [xres, yres] that specifies the pixel resolution.

### GEO_VALID

Set this keyword to a named variable that will contain a long integer that is set to:

- 1 - If the MrSID image contains valid georeferencing data.
- 0 - If the MrSID image does not contain georeferencing data or the data is in an unsupported format.

Note: Always verify that this keyword returns 1 before using the data returned by any other GEO_* keyword.

### LEVELS

Set this keyword equal to a named variable that will contain a two-element long integer array of the form [minlvl, maxlvl] that specifies the range of levels within the current image. Higher levels are lower resolution. A level of 0 equals full resolution. Negative values specify higher levels of resolution.

### PIXEL_TYPE

Set this keyword to a named variable that will contain the IDL basic type code for a pixel sample. For a list of the data types indicated by each type code, see the “IDL Type Codes” section of the SIZE function.

### TYPE

Set this keyword to a named variable that will contain a string identifying the file format. This should always be MrSID.

## Examples

PRO MrSID_GetProperty

; Initialize the MrSID object.

oFile = OBJ_NEW('IDLffMrSID', FILEPATH('test_gs.sid', $

SUBDIRECTORY = ['examples', 'data']))

; Get the property information of the MrSID file.

oFile->GetProperty, CHANNELS = chan, LEVELS = $

lvls, Pixel_Type = pType, TYPE = fileType, GEO_VALID = geoQuery

; Print MrSID file information.

PRINT, 'Number of image channels = ', chan

; IDL returns 1 indicating one image band.

PRINT, 'Range of image levels = ', lvls

; IDL returns -9, 4, the minimum and maximum level values.

PRINT, 'Type code of image pixels = ', pType

; IDL returns 1 indicating byte data type.

PRINT, 'Image file type = ', FileType

; IDL returns "MrSID"

PRINT, 'Result of georeferencing data query = ', geoQuery

; IDL returns 0 indicating that the image does not contain

; georeferencing data.

; Destroy object references.

OBJ_DESTROY, [oFile]

END

## Version History

5.5 | Introduced