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I have encountered a serious problem when using tracking markers: I tracked a single point over a range of 3000 frames in small steps e.g. I manually corrected the position every 50 frames. When rewatching the 50 frames, all the tracking seems to be very accurate. However, when I rewatch the whole footage, suddenly in some ranges the accuracy is terrible. But somehow these ranges vary and are at different positions from time to time. Even more surprising is that even those frames at the beginning of the 50 frames, which HAVE to be correct, aren't. To me it seems like there is either some offset in the displaying of the markers, or they get saved wrongly somehow. Has anyone an idea, what could be the reason for this?
EDIT: Just changing the input format from .mp4 to .png solved the problem completely.