Removing black background on stock footage

[Wayne Waag]

If I’m not mistaken, Vegas pro only reads the alpha channel from an uncompressed avi. Here is a link of someone asking a similar question a couple of years ago.

https://www.sonycreativesoftware.com/forums/showmessage.asp?messageid=887405

Here is a link on converting a mov with alpha to uncompressed avi. One option that seems to work is to convert the mov to a png sequence with ffmpeg.

https://forum.videohelp.com/threads/365319-convert-mov-with-alpha-channel-to-AVI-with-RGBA

In any case, good luck and report back if you find something that works for you.

wwaag

[John Rofrano]

What codec do the files use? Open them in QuickTime Player and use Ctrl+I to bring up the inspector windows and see what codec the video uses. It needs to be able to carry an alpha channel in order for Vegas Pro to see it.

~jr

http://www.johnrofrano.com
http://www.vasstsoftware.com

[John Rofrano]

[Wayne Waag] “Vegas pro only reads the alpha channel from an uncompressed avi.”

Actually, Vegas Pro handles alpha channels in QuickTime MOV files just fine. The link you pointed to in your post had to do with MOV files created in Avid. No one supports Avid’s alpha channels because they are backward. Vegas Pro supports QuickTime alpha channels with the Animation codec, the PNG codec, and ProRes 4444 codec in addition to uncompressed.

~jr

http://www.johnrofrano.com
http://www.vasstsoftware.com

[Linda Long]

Here is a link to two files I was trying to use:
https://www.dropbox.com/s/2z6kyuk73cnyzlj/99175_goldenFiligree_HD1_Alpha.mov?dl=0
https://www.dropbox.com/s/ajorscwkwh90gu8/99175_goldenFiligree_HD1_DA_Wipe.mov?dl=0

[John Rofrano]

[Linda Long] “Here is a link to two files I was trying to use:”

Hi Linda,

Those files are Photo JPEG and do not contain an Alpha Channel. What you have is Matte video that can be used to mask the Wipe video. You need to:

• Place the 99175_goldenFiligree_HD1_Alpha.mov video on the top track.
• Place the 99175_goldenFiligree_HD1_DA_Wipe.mov video on the track below it.
• Place your background video on a track below both of those.
• Change the Compositing Mode of the top track to with the matte video to Mask (Multiply)
• Change the second track with the Wipe to be a Compositing Child of the top track.
• Add the Mask Generator to the Alpha matte Event to make the black turn transparent.

Here is a picture of what you should see:

~jr

http://www.johnrofrano.com
http://www.vasstsoftware.com

[Linda Long]

Thank you so much for taking time to post such a nice set of instructions. I will work on this a bit later this a.m. and get back to you!

[Linda Long]

That worked! Thank you so much!

Check out my blog full of reading lists of some of the best books for children, homeschool or unit studies.
https://readingvoyages.blogspot.com/

[Wayne Waag]

[John Rofrano]

As always, I learn something new which invariably, for me at least, suggests the need for a database of tips, tricks, and techniques. Oftentimes, these gems are buried within a thread and unlikely to be found through normal searches. How to organize and maintain such a database is another matter. Just an idea.

One other thing–what screen shot software do you use? It’s really nice

wwaag

[Linda Long]

Ok, one more question along these lines. I have some other .mov files that I got from digitaljuice.com that are supposed to be used for transitions. They only have one file and I am a loss as how to use these. I have the same black background instead of transparency issue.

Since I only have one file, I’m not sure how to use these.

Here is a sample file:
https://www.dropbox.com/s/eru9z6v1qk2syaq/colored-stripes-closing-door-transition-yellow_Zy4_ZRdeB.mov?dl=0

Check out my blog full of reading lists of some of the best books for children, homeschool or unit studies.
https://readingvoyages.blogspot.com/

[Andrew Lenczycki]

I have quite a bit of the Digital Juice products. You would position the “colored stripes closing” event on a track above the two events you will be transitioning from (A to B). At the point where the A & B events meet, you will position the “colored stripes” event so the stripes are where they completely obscure the two events below, AND you must right click on that event and set the Properties|Media|Alpha Channel to Straight (Unmatted).) This will make the black portions of the “colored stripes” video transparent (so you can see your other 2 video events “behind” the “colored stripes”).

Andrew Lenczycki