Auto-Screenshot

The Auto screenshot feature can generate a screenshot of a WaveView window at regular intervals, and save the image to a file in PNG (Portable Network Graphics) format. Scream can then run a user-specified program, supplying the image file name as a parameter. This allows the user to automate many display-related tasks, including a regular update of waveform data on a web site, or periodic sampling of data quality for quick visual inspection, etc.

To access the auto-screenshot options, click the down arrow on the print button , and select "Auto-Screenshot..." from the menu. The following options are available:

Every [X] [Seconds | Minutes | Hours | Days ]

Specifies how often scream should generate a screenshot

Save to File

Enter the file name, and full path of the file you want the image saved to. Extension should be '.png'.

Execute Command

After the image is saved, Scream will run this command line, adding the file name as parameter. Useful for handling the file automatically, e.g. FTP to web site, email, etc.

Force Size [X] x [Y] pixels

Fixes the size of the WaveView window so that the generated image will be exactly this size.

Null before capture

This option is equivalent to the user pressing the "Null Offsets" button immediately before the image is captured. Note that this will cause the window to be re-drawn, so any spectrogram display will be erased.

Auto-Scale before capture

This option instructs scream to automatically re-scale the amplitude scaling to ensure all data is visible. Note that this will cause the window to be re-drawn, so any spectrogram display will be erased.

Note that it is not necessary to specify a file name for the saved image. In this case, no screenshot will be taken, but any other option that is selected will still operate. For example, enabling only "Every 1 minute" and "Auto-Scale" has the effect of keeping the WaveView window display always on-scale.

See Also: Print Features