Field misalignment
Field misalignment happens when video is resized as separate fields without taking into account that when a video is stored as fields, those fields each have a unique spatial offset relative to the other. It can be fixed within the limits of linear interpolation if you know the exact way in which the misalignment was introduced, obviously such information is not usually available. Barring an exact solution you are left with various flavors of blur, which all essentially function by removing the aliased high frequency vertical information that differentiates the fields from each other. (source: *.mp4 guy)
The lines “less oblique than the actual lines” are generally caused by fields individually resized without taking their vertical positions into account. Fortunately the process is more or less non-destructive in the upscale case and can be reverted by resizing the fields to their original size. Finding the exact size is a matter of trial and error. When you get close, it shows some beating patterns that become larger and larger until they disappear completely when you hit the exact size. (source: cretindesalpes)
External Links
- Doom9 Forum - How to deal with this? (field misalignment)
- Doom9 Forum - Need help TIVTC'ing/Deinterlacing a clip...
- Doom9 Forum - Help with Babylon 5 scaling
