The Wyko Vision ASCII File Format

Summary

The Wyko Vision has three different measurement output data formats: the WYKO dataset (.opd), ASCII dataset(.asc), and SDF dataset (.sdf). The .opd and .sdf are binary and so far closed standards. Therefore, currently the ASCII format is the only available format as the input to our algorithms.

A .asc file consists of three major parts: the header, the z-profile array, and the intensity array (optional). A typical floating point, XYZ-triplet-pixel data file looks like:

The header: (partial)

Wyko ASCII Data File Format 1,0,1
X Size,640
Y Size,480
Block Name,Type,Length,Value ......

The z-profile array: (partial)

0,0,399.202118
0,1,397.400635
0,2,395.085144
......

The intensity array: (partial)

Intensity,3,1228800,
0,0,14.362668
0,1,8.262820
0,2,1.813468
......

Various combinations of file saving options can affect the content of each part. The influences on data layout format are summarized in Various File Saving Options and the Data Format. See the following sections for detail.

Header

The header is an array of lines of data blocks. Each block consists of fields of title, byte-length, and value separated by delimiters. See The Table of the Complete Header Information. See Various File Saving Options and the Data Format for detail on how different file saving options affect the header information.

Data Arrays

See Various File Saving Options and the Data Format for detail on how different file saving options affect the data.

Various File Saving Options and the Data Format

There are five independent option pairs that affect the output data format.

There is another option of saving bad pixels as Null. However, this proves to cause Vision to incorrectly read the data. So the option is banned for now.

Existing Problems

Reference

Veeco Metrology Group. 2003. WYKO NT8000 setup and operation guide. Tucson: Veeco Instruments, Inc.