TL;DR: Apparently the compression setting was set to the minimum value. Changing that fixed the problem.
--- Investigation log: 1. Pointing LD_LIBRARY_PATH to a restored backup of /usr/lib/x86_64-linux-gnu does not help. 2. "strace -f" shows no external programs are called to handle compression/saving. 3. Looking at the simple-scan sources, there must be a quality setting somewhere in the GUI? But it's not in Preferences, where I believe there used to be such an option? 4. Found it: when the file format at the bottom of the save dialog is set to JPEG or PDF, a small "Compression" slider is shown next to it, which I had never noticed before (I always change file format by editing the file name + extension at the top). This was set to its minimum value. 5. Moving the slider to the right fixes the issue for me. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to simple-scan in Ubuntu. https://bugs.launchpad.net/bugs/2024887 Title: Bad image quality when saving JPEG or PDF scans Status in simple-scan package in Ubuntu: New Bug description: Description: Ubuntu 22.04.2 LTS Release: 22.04 simple-scan: Installed: 42.0-1 Candidate: 42.0-1 Version table: *** 42.0-1 500 500 http://be.archive.ubuntu.com/ubuntu jammy/main amd64 Packages 100 /var/lib/dpkg/status When saving a document scanned using "Image" settings to JPEG or PDF format, the resulting quality is really bad. The image shown in the scan window looks fine, so this is not a scanner issue. When saving to (lossless) PNG, the quality is also fine. This is also reflected in the file sizes, e.g. for a 600 dpi scan of a 19x13 cm photo: - PNG: 12575069 bytes (OK) - JPEG: 227595 bytes (BAD) - PDF: 229414 bytes (BAD) It looks like the compression rate for (embedded) JPEG files is way too large. When scanning using "Text" settings, the resulting quality is fine (I rescanned an old document and compared the results). The difference with a scan using the "Image" settings is very clear, even for text documents. Version 3.36.3-0ubuntu0.20.04.0 did not have this problem. I downloaded and installed 42.5-1 from kinetic, but that did not fix the issue. Thanks! To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/simple-scan/+bug/2024887/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
