Encoding quality of background layer, expressed as integers ranging from 1 to 140. The default is 72+11+10+10. Each number corresponds to the quality of the successive wavelet refinements, for example:
72: wavelet layer
11: refinement 1
10: refinement 2
10: refinement 3
NOTE: --bg-slices is not compatible with --bg-quality. The default corresponds to --bg-quality.
Example
pdftodjvu
--bg-slices=80+12+50+50 document.pdf [document.djvu]