I'm having an issue with jumpy playback on a file that originated as an Avid export (29.97 fps, Avid DNxHD codec) and, using Quick Time 7 Pro, got transcoded to H.264 to meet YouTube's and Vimeo's upload specs.
Here's the issue: tilts on still photos, which are smooth as silk in the direct Avid export (file size 900 MB) are jumpy on QT conversions to H.264. (They get even jumpier after being uploaded to YouTube and Vimeo.) I've tried various QT settings: native frame rate (29.97 fps) and 30 fps; key frames set to automatic; frame reordering checked and unchecked. I've also tried bit rate settings from automatic to 3000 and upwards, by 1000 increments, to 10,000. I'm wondering if this could have something to do with the smaller file size produced by the conversion. The biggest file I've gotten, coming out of QT, is about 73 MB (from an original that's 900 MB). My system is Avid Media Composer 6.5.2 Academic on an iMac (OS 10.8.4 with 16 GB RAM.) Thanks.↧