I'll leave the original text, but suffice it to say that the MC encoder does appear to be placing I-frames accurately; the confusion arose because of the assumption that the I-frame needed to be placed in the presentation order position, and no such requirement exists.
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Just a quick "beware" for folks using the new V7 feature with having I-frames set at markers from Vegas.
After I lot of research into a different problem, I've found that the MC encoder is not always frame accurate when placing the I-frames, and DVDA lies about it (or at best, doesn't really know the truth, since it appears to be only taking it's cues from the marker info exported from Vegas and isn't confirming it against the actual MPEG data).
Anyway, I had a project that I put the timecode on the video showing frame numbers, with a marker at frame 663. GSpot was claiming that the I-frame was actually on frame 665, DVDA said the marker (chapter 7 in this case) was on 663 (and even showed me a preview showing frame 663).
However, when I authored this with DVDA and examined the result with PGCedit, asking it to display the frame at Chapter 7, the resulting image was frame 665, just as GSpot had been claiming was the location of the nearest I-frame.
This didn't just happen once in the project, but a total of 3 times in 8 chapters where things were off by 1 or 2 frames.
This wouldn't be noticed probably if you had a few frames around the area that were similar.
--Scott
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Just a quick "beware" for folks using the new V7 feature with having I-frames set at markers from Vegas.
After I lot of research into a different problem, I've found that the MC encoder is not always frame accurate when placing the I-frames, and DVDA lies about it (or at best, doesn't really know the truth, since it appears to be only taking it's cues from the marker info exported from Vegas and isn't confirming it against the actual MPEG data).
Anyway, I had a project that I put the timecode on the video showing frame numbers, with a marker at frame 663. GSpot was claiming that the I-frame was actually on frame 665, DVDA said the marker (chapter 7 in this case) was on 663 (and even showed me a preview showing frame 663).
However, when I authored this with DVDA and examined the result with PGCedit, asking it to display the frame at Chapter 7, the resulting image was frame 665, just as GSpot had been claiming was the location of the nearest I-frame.
This didn't just happen once in the project, but a total of 3 times in 8 chapters where things were off by 1 or 2 frames.
This wouldn't be noticed probably if you had a few frames around the area that were similar.
--Scott