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Chengbin
9th September 2009, 04:05
Videos encoded with MBtree seems to have strange seeking. i.e. it would skip in large blocks. Therefore I almost always jump too far, even though I didn't hold the FF key for very long. Videos without MBtree seems to skip to every I frame. The seeking is smooth.

Sagekilla
9th September 2009, 07:12
MBtree shouldn't affect decoding in any noticeable way.

Have you checked the distribution of I Frames? Are there fewer I's with MBtree on? If so, that could be the cause why.

Chengbin
9th September 2009, 13:05
How do I check for the distribution of I frames?

juGGaKNot
9th September 2009, 13:32
Yes, lately i noticed that on a 3 minutes sample i only get 4 i frames, before 28 i think

Sagekilla
9th September 2009, 18:45
How do I check for the distribution of I frames?

--stats "file.stats"

x264 also prints the number of I Frames that get encoded by default

benwaggoner
13th September 2009, 22:48
Yes, lately i noticed that on a 3 minutes sample i only get 4 i frames, before 28 i think
If random access performance isn't good enough, a smaller max GOP duration is probably in order. The default of 250 is pretty darn long. I tend to use 4 second GOPs for most HD content, so 96 frames with 24p.