Poor score recognition (2)
Far more than a human spectator capella-scan relies on distinct, unchanging shapes. In spite of sophisticated technology the scope is limited: An experienced musician might perceive a score as still quite legible whereas capella-scan cannot process it at all.
Pale photocopies with broken lines, holey note heads, stems not meeting heads are causing difficulties. You can perceive them when you enlarge the image.
Handwritten notes or smudges will also affect recognition.
When your score looks like this, capella-scan will be able to recognize only little:
This quality is not suitable as well:
Here is a grayscale scan with too low resolution - hopeless:
