---
name: "lookamb"
section: "1"
platform: "linux"
package: "radiance"
version: "4R1+20120125-1+b1"
release: "Debian 7 (Wheezy)"
platforms: ["linux"]
url: "https://new.carta.tech/lookamb"
---

# lookamb(1)

examine ambient file values

## NAME

lookamb - examine ambient file values

## SYNOPSIS

**lookamb** \[ **-d** \]\[ **-r** \]\[ **-h** \] \[ **ambfile** \]

## DESCRIPTION

*Lookamb* examines an ambient file produced by *[rpict(1)](/rpict/1.md),* *[rtrace(1)](/rtrace/1.md),* or *[rvu(1)](/rvu/1.md).* The default mode prints the position, direction, level, weight, radius, value, position gradient and direction gradient for each stored ambient value preceded by a label appropriate for human interpretation. The  *-d* option prints the same quantities in 18 columns without any expanatory text, and is more appropriate as input to another program.

The *-r* option performs the reverse conversion, taking the output of lookamb and reproducing the original ambient file on the standard output.

The *-h* option causes lookamb not to print out the header information on the output, or not to expect it on the input with the *-r* option.

If no file is given, *lookamb* reads from the standard input.

## NOTES

Before release 2.2 of Radiance, ambient files were in a machine-dependent format. Since that is no longer the case, ambient files can now be moved freely between machines without any conversions. Thus, the only reason to use *lookamb* now is to examine the contents of an ambient file.

## AUTHOR

Greg Ward

## SEE ALSO

[getinfo(1)](/getinfo/1.md), [oconv(1)](/oconv/1.md), [pfilt(1)](/pfilt/1.md), [pinterp(1)](/pinterp/1.md), [rpict(1)](/rpict/1.md), [rtrace(1)](/rtrace/1.md), [rvu(1)](/rvu/1.md)