WOH waveform is used to generate waveform images used by the video editor. While it is possible to statically configure the image size of the generated waveform image, this can't be done dynamically in means of per-execution (using a workflow configuration key).
Depending on the use of the waveform image, it would be desirable, however, to be able to extract low-res waveform images.
Use case example:
In https://opencast.jira.com/browse/MH-12814, for example, we envision using waveform images as visual representation of audio tracks ("more sexy"). A resolution of something like 640x40 pixels would be more than sufficient for this use case.