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View Full Version : App to visually verify field order?


miamicanes
15th September 2007, 23:15
Is there any program that allows you to view arbitrary video files that:

* allows you to step forward or backwards through them exactly one field at a time

* Displays the video some exact multiple of the monitor's resolution, cropping the playing video if necessary, and NOT blending or modifying it in any way. In other words, it might show a 720 x 480 DV video on a display that's 1280 x 1024 by decoding each field, and showing each pixel four times... two side by side, above another two identical pixels. Or 3x3. Or 4x4. If it exceeds the monitor's resolution, it just crops it to the window size and allows you to pan around to see different parts of the field.

* Displays the non-current scanlines in either black or dimmed to a fraction of their previous value, to make it visually obvious that they belong to the previous field.

The problem I have is a video that seems to shift back and forth after noise bursts from the original capture between having the fields in order and having the fields out of order. I'm having a hell of a time trying to conclusively confirm the behavior, because all of the viewing apps I have are designed for viewing content rather than debugging it, and make it really hard to tell what's actually going on at any given instant because of the way they scale and blend everything together.

Guest
15th September 2007, 23:37
Use Avisynth and its SeparateFields() function. You can view the fields directly.

Use AssumeTFF() and AssumeBFF() to see the effect of forcing different field orders. E.g., to see the effect of assuming it is TFF:

AssumeTFF().SeparateFields()

A motion sequence should move steadily and not jump forward and backward.

Sorry for being cryptic, I have to go swim some sprints with the ten-pound weight belt. Hammer down!