Velocity Envelope Problem - Vegas Pro

Douglass-Ray wrote on 12/18/2022, 2:15 PM

This may be complicated, but here goes: I'm finding that the velocity envelope works perfectly on MP4 and MOV clips, but not on mts or png clips. (This on both Pro 19 and Pro 20). Is this right? My problem is I'm superimposing png clips with graphics over video (the graphics have motion created via the pan/crop function, and I'm placing the clips on a title track) which works fine -- but then I need to vary the speed of the graphic's motion throughout the clip, and varying the speed is only possible with the envelope (and no other velocity alternative). But in order to get the velocity envelope to work, I have to convert the png clips to MP4. That works -- but you can't superimpose MP4s -- with graphics against black -- over another video. If this is really incompatibility between png and the envelope, is there another codec to which I can convert my png clip so that it CAN work with the velocity envelope without blocking the video on the the video track? Thanks.

Comments

jetdv wrote on 12/18/2022, 2:42 PM

You have to render to a format that supports alpha channel. Then the background will remain transparent. MP4 does not support alpha channel. ProRes does. Uncompressed AVI does. Or you could try using a Nested VEG file with that image in it.

I did add an image with a straight zoom and then popped a velocity envelope on it. The envelope did nothing to the zoom speed.

Dexcon wrote on 12/18/2022, 4:09 PM

Just to add to jetdv's comment about .AVI, the render process is to use the Video for Windows render option, choose your Frame Size (I use a custom setting for 4K), select Uncompressed in 'Video Format' and check the Render Alpha Channel checkbox. This will render to .AVI with an alpha channel, but the rendered video will be large.

After importing the render onto Vegas Pro's timeline, R click the .AVI video event, select Properties and then the Media tab, and select an alpha selection in the 'Alpha Channel' field.

Douglass-Ray wrote on 12/18/2022, 6:23 PM

jetdv: Thank you for your (Dexcon's) clarification . Regarding your point that a png is a still image -- I create the motion by using pan crop -- which creates steady movement in the png on the timeline (such as in scrolling -- which is what I need to do -- scrolling end-credits, ending with the scrolling of a company logo, which needs to slow to a stop in the center of the screen before fading out.) I'll follow your advice. Thanks!

fr0sty wrote on 12/18/2022, 10:20 PM

Are you familiar with using keyframes to move the clip around over a period of time? That is how your control the velocity of the movement. Also, track motion or the picture in picture effect might prove easier to use than pan/crop. PIP comes with the advantage of the controls being overlaid directly onto the preview monitor, vs. having to move it around in a separate window.