MSP: Twinkle a Star....using REGION

[Terry Stetler]

In another thread this question was posed;

What would be the best way to create a "twinkle" on a lone star on a black background in an introduction? I have been experimenting with this in CG Infinity and the results were resonable but if there is an easier or different way to achieve a better result I would be very grateful for any help.

There are a couple of ways to do this in either MSPro7 or MSPro8.

One would be to use the Star video filter and keyframe it to create and vary the intensity/size/color of one or more stars, but that's too simple

More instructive is to use this as a way to teach the use of the REGION function for video filtrers like Brightness & Contrast. Here's the step by step;

1. draw your starfield in the same size as your video frame and save it as a BMP.

I like to use a tool like Diard Softwares Universe Image Creator to do this as it lets one add features to the image like starfields, nebulae, galaxies, gas clouds, globular clusters, planets etc. While full features require paying and registering, the shareware version is more than enough for 90% of people as it can still do starfields, nebulae, gas clouds and globular clusters;

http://www.diardsoftware.com/index.html

Example:



The below image wasn't done in UIC, but in PhotoImpact using the Particle/Stars tool. This "look" is simpler for purposes of an online example w/small images;



2. load the saved image into your image editor and ERASE to BLACK all but the star you're interested in. Easiest done by choosing a large brush and black as the color;



3. now choose a brush about the same size as your star and set the image editor to feather the edge of the brush. In Photoshop this is done by choosing a gradient brush, but in PhotoImpact this is set by a slider in the brush toolbar. Now pick the color WHITE and just stamp directly over the star. This was done in PhotoImpact with a brush size of 20 (zoomed for clarity);



Now save this image as a BMP but with a different name. This is your matte.

4. now that the drudgery is over here's the fun part. Place the starfield on Va or Video1 (depending on your version) and open the context menu's Video Filters dialog. Pick the Brightness & Contrast filter.

5. still in the Video Filters dialog click the REGION button. In REGION set the Type to "Gray Key" and the Mask to "Image Matte", which will bring up a file dialog from which you load your matte image. Set the Threshold to a rather low, but steady, value. I use about 20 or so.

6. now keyframe the Brightness & Contrast filter to suit. I keep the brightness no higher than +20 and with a minimum of -20 to -50. Set the gamma and contrast to be constant. More keyframes closer together make for a faster, more natural looking twinkle.

Here's what you'll get;

http://digitalvideo.8m.net/tutorials/tw ... /stars.wmv

Full sized bitmaps used in this tutorial;

http://digitalvideo.8m.net/tutorials/tw ... /stars.bmp
http://digitalvideo.8m.net/tutorials/tw ... smatte.bmp

[Martin Keith]

Thank you Terry, now I know why I joined this forum. I hope I can give something back in the future.

[DarrenD]

Terry

I get a 404 error when accessing the .WMV file. Have you moved it?

[sjj1805]

Terry
Another "Well done" now why on earth didn't you put these into the "Best Practice" competition. I am sure you would have won!!

Best regards
Steve J

[Terry Stetler]

Terry

I get a 404 error when accessing the .WMV file. Have you moved it?

The link works here. Try right-clicking and downloading it. It's not that big at 64k.

[Terry Stetler]

Terry
Another "Well done" now why on earth didn't you put these into the "Best Practice" competition. I am sure you would have won!!

Best regards
Steve J

Thanks Steve, but I already have an IPod and about every Ulead program. IMO it's better to have someone win a prize that doesn't already have it.

[Greg]

And now to demonstrate the sheer beauty of the nested timeline!

Follow Terry's instructions for creating the starfield and matte, then repeat on a different star and save the output to matte2.bmp

In MSP, create a second timeline, and follow Terry's instructions for creating the twinkling effect. Then go to the main timeline and insert from timeline 1, and again follow the instructions, only space your keyframes differently, and set the upper and lower brightness values differently.

Repeat as many times as you like.

The effect? -- multiple stars all twinkling at different rates and brightness.

This is really serious fun!

Regards,
Greg

[TubaDad]

Terry, I am having the same problem with getting a 404 error when trying to access your WMV file.

I also wanted to tell you how much I appreciate the tutorials that you have written and shared. They would have easily taken the prizes. Your selflessness is a rare thing now days. Thanks again.

Hopefully, Ulead and the moderators will take Steve's suggestion from another thread and keep a place that tutorials can be stored. I have always found it better to go through tutorials of users than vendors.

Thanks again.

[Terry Stetler]

As noted right-clicking and selecting Save As should let you download it. I've tried it on this and a neighbors machine and that works so....

Given the response to this tutorial, and the lack of my ability to upload this to a tutorial forum, I'm making this post a Sticky so it'll stay readily avaiable.

Thanks for the good words guys

[Terry Stetler]

Found the problem with the link: my space provider turned off remote file access when I upgraded my account. Go figure

[sjj1805]

Terry,
The link is working now. just double click the link and it opens up in Windows Media Player.



Steve