Hey, I just came across an explanation for the render setting “Seconds per keyframe” found in the WMV9 custom template video tab. If there’s a discussion on this in the manual, I somehow missed it. Thanks SonyTSW.
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Subject: RE: Problem with WMV file
Posted by: SonyTSW (Ignore This User)
Date: 5/27/2003 11:02:27 PM
Some WMV files have been encoded with very few keyframes (this is Windows Media terminology, not to be confused with Vegas keyframes). These keyframes are frames that are independent from other video frames in the video stream and are needed for random seeking.
If your WMV files have very few keyframes then you will have trouble incorporating them into your Vegas projects. I've come across some WMV files that had only one single keyframe, which was the very first frame in the file.
Vegas needs to do somewhat random seeking, in order to display thumbnails for the video frames in the events, in the media pool for the Thumnail view, in the trimmer if you've got the animate video frames in trimmer preference enabled, and so on. WMV files which have very few keyframes are likely to display black frames for these thumbnails and animations, and also will show black frames in the video preview window when you click the cursor around to different places in the timeline.
One simple test is to first start playing the WMV file in the Windows Media Player. While it is playing, drag and drop the seek cursor to another location. If it jumps only a few different locations (depending where you dropped it), or worse it always returns to where it is currently playing, then it is a good bet you are going to have trouble with that file in a Vegas project.
You may need to use the Windows Media Encoder to re-encode such WMV files so they have more keyframes for better seeking behavior in Vegas. Make sure the keyframe interval is set to several seconds or less (WME 9 defaults to 2). The encoder is a free download from Microsoft.>>>
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Subject: RE: Problem with WMV file
Posted by: SonyTSW (Ignore This User)
Date: 5/27/2003 11:02:27 PM
Some WMV files have been encoded with very few keyframes (this is Windows Media terminology, not to be confused with Vegas keyframes). These keyframes are frames that are independent from other video frames in the video stream and are needed for random seeking.
If your WMV files have very few keyframes then you will have trouble incorporating them into your Vegas projects. I've come across some WMV files that had only one single keyframe, which was the very first frame in the file.
Vegas needs to do somewhat random seeking, in order to display thumbnails for the video frames in the events, in the media pool for the Thumnail view, in the trimmer if you've got the animate video frames in trimmer preference enabled, and so on. WMV files which have very few keyframes are likely to display black frames for these thumbnails and animations, and also will show black frames in the video preview window when you click the cursor around to different places in the timeline.
One simple test is to first start playing the WMV file in the Windows Media Player. While it is playing, drag and drop the seek cursor to another location. If it jumps only a few different locations (depending where you dropped it), or worse it always returns to where it is currently playing, then it is a good bet you are going to have trouble with that file in a Vegas project.
You may need to use the Windows Media Encoder to re-encode such WMV files so they have more keyframes for better seeking behavior in Vegas. Make sure the keyframe interval is set to several seconds or less (WME 9 defaults to 2). The encoder is a free download from Microsoft.>>>