Bug 23963: Revert bug 21987 to restore image quality

Bug 23963: Revert bug 21987 to restore image quality

Bug 21987 had unexpected effects upon image quality for thumbnails.
Currently, we are working to resolve those issues but have not managed
to correct them inside the release window for this cycle. As such, I
have chosen to revert the original bug whilst we work on a resolution.

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
(cherry picked from commit 35670b0495e0333f57773b0375ea7aa1122d5372)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>