Routines (alphabetical) > Routines: Q > QUERY_PPM

# QUERY_PPM

QUERY_PPM is a method of obtaining information about a PPM image file without having to read the file. See QUERY_* Routines for more information.

## Syntax

Result = QUERY_PPM ( Filename [, Info] [, MAXVAL=variable] )

## Return Value

This routine returns a long with the value of 1 (one) if the query was successful (and the file type was correct) or 0 (zero) on failure.

## Arguments

### Filename

A scalar string containing the pathname of the PPM file to query.

### Info

Returns an anonymous structure containing information about the image. The Info.TYPE field will return the value ‘PPM’.

Additional field in the Info structure: MAXVAL - maximum pixel value in the image.

Note: See General Query * Routine Info Structures for detailed structure information.

## Keywords

### MAXVAL

Set this keyword to a named variable to retrieve the maximum pixel value in the image.

## Version History

5.2 | Introduced

## See Also

QUERY_* Routines, READ_PPM, WRITE_PPM