Green screen experiment and timeline questions

[braindeadsoftwareguy]

I was horsing around with a silly green screen test. When I dragged my video to the timeline, a dialogue box said that I had a solid color background and do I want to apply "videomerge". At first I said no, but the green screen affect did nothing to the video. I then tried it with videomerge and the video became a darkened background already. The green screen effect was redundant after that.

Do I need videomerge or was my green screen video just plain wrong?

Second question is, I had one solid frame on the timeline. I toggled the icon on the left, but couldn't get the multiple frames. How to I do that from a one frame image there?

[Steve Grisetti]

When you apply a Chroma Key (or Green Screen or Blue Screen Key) you need to define the key color (your background) in the Properties panel in order to make your background transparent.

Videomerge defines your key color automatically, based on whatever smooth color it sees in the background.

So Videomerge is a more automatic version of a Key effect.

The reason your background becomes black is because you don't have any video on the video track below your current clip. So, when Videomerge made your background transparent, it appeared black.

[Bob]

Second question is, I had one solid frame on the timeline. I toggled the icon on the left, but couldn't get the multiple frames. How to I do that from a one frame image there?

Are you sure you clicked the icon on the left of the track name that looks like a frame from a piece of film? Each time you click that icon, the style should change. Keep clicking it until you get the one you want. The styles are: multiple frames, single frame on left, two frames -- one on each end of the clip, and no frames.

[braindeadsoftwareguy]

I clicked the icon to the left that looks like a frame over and over again, but it just went between a single frame with a picture and a single frame with a line. No other choices? I did have the individual frames once before when I was messing around some weeks ago, but not this time.

I once watched a Youtube tutorial and the woman didn't choose the color from the properties first, just did the green screen key? This shows my original sentiments from my original posts, that there is always assumptions when someone is teaching these programs. They often leave out key points and don't detail each and every step. Maybe because of their own familiarity.

[Bob]

I don't have PrE 10, so I can't try it myself. But, the PRE 10 documentation says it works the way I described. And, it certainly works that way in the earlier versions I have used. It may be a bug or an undocumented change in the behavior of PRE 10. Sorry.

Videomerge is a different type of key extractor than the green screen effect. And, it can be very effective in many situations. In other situations, you may be able to pull a better key from the other key effects. By default, it attempts to select the keying color. If you go into the properties panel, you can override that and select your own color. There is also a tolerance bar that can modify the color range removed. Don't go too far or you will likely introduce semitransparency where you don't want it or affect color balance.

The green screen key effect doesn't let you select the color, but you almost always need to adjust the threshold and cutoff controls to get a good key. You want to lower the threshold until you get an optimum green removal and raise the cutoff to prevent excess transparency in the subject. If you check the mask only box, you'll see the black and white mask used for the extraction and you can easily see the result of changing the threshold and cutoff values. Here's an example. The left image has the threshold too high, the middle image has the cutoff too low, the right image has good threshold and cutoff values. Black is totally transparent, gray is partially transparent, white is opaque.

greenscreenmask.jpg

[braindeadsoftwareguy]

I don't have PrE 10, so I can't try it myself. But, the PRE 10 documentation says it works the way I described. And, it certainly works that way in the earlier versions I have used. It may be a bug or an undocumented change in the behavior of PRE 10. Sorry.

Videomerge is a different type of key extractor than the green screen effect. And, it can be very effective in many situations. In other situations, you may be able to pull a better key from the other key effects. By default, it attempts to select the keying color. If you go into the properties panel, you can override that and select your own color. There is also a tolerance bar that can modify the color range removed. Don't go too far or you will likely introduce semitransparency where you don't want it or affect color balance.

greenscreenmask.jpg

The green screen key effect doesn't let you select the color, but you almost always need to adjust the threshold and cutoff controls to get a good key. You want to lower the threshold until you get an optimum green removal and raise the cutoff to prevent excess transparency in the subject. If you check the mask only box, you'll see the black and white mask used for the extraction and you can easily see the result of changing the threshold and cutoff values. Here's an example. The left image has the threshold too high, the middle image has the cutoff too low, the right image has good threshold and cutoff values. Black is totally transparent, gray is partially transparent, white is opaque.

Thanks Bob. I can see those image changes. Again, I have to say that I'm sure this program has all sorts of ability but one should not have to spend ages trying to sort it all out on their own or asking questions online. There should be a manual like Steve's supplied with the program. I go back to my analogy of plunking a person into a pilot's seat without a manual and expect him to take off and fly the plane, then land, even though he knows what a plane should do.

[Steve Grisetti]

But that's not really fair, bd. Green Screen and Chroma Key are pretty high-level special effects!

Videomerge does them nearly intuitively, as you've already found. But you do have to come at an effect like this with some basic understanding of what's going on. After all, you'd never open up a copy of Word and try to lay out a newsletter without understanding how layout, columns and text wraps work, right?

BTW, I hear you've now got a copy of my book! Check out the special articles on Chroma Key and Videomerge in the Effects chapter! It should make the steps for achieving this effect simple and clear.

[Chuck Engels]

Just because I drive a car doesn't mean I could rebuild the engine, or simply replace the brake pads.
A good manual and the internet are definite must haves these days.

I do a lot of work on our appliances at home; washer, dryer, disposal and a few other things.
I can wash clothes and dry them but would be lost trying to fix either machine without the help of the internet. Some people could simply fix the machines without much help, not me.

Software is no different, some people find it intuitive, others struggle to understand.
Most times we struggle because we make it too difficult, in most cases it isn't as hard as we try to make it. The answers are as close as your computer, easier than taking your car to the repair shop

People take classes given by professionals in how to use these kinds of programs. Photoshop, Premiere (whether pro or elements), After Effects, Dreamweaver, and others are not simple programs. They are complex and require instruction, more instruction than you can get out of a manual most times. That's why we provide help in the community, video tutorials and books as well as articles. There is so much to learn, so many ways to do things, and so many kinds of people with different learning abilities, we need to provide many vehicles to learn the software.

Steve's book will be a great help and you still will probably have some questions. That's what we are here for. I don't think you can find any similar software that doesn't require any help, it just doesn't exist. Be glad that you picked something that has so much support available it will be hard not to learn how to use it

[braindeadsoftwareguy]

"After all, you'd never open up a copy of Word and try to lay out a newsletter without understanding how layout, columns and text wraps work, right?"

I don't have Word or even understand most of it, especially the Spread Sheet stuff. I simply do letters and notepad, etc. Heck, I can't even type. I'm not really a computer type guy. Unfortunately this is where the systems are to do things I want to do. If I could stay with mechanical devices to do my work, I'd be much happier. I have a guitar amp that has your basic knobs. I gave it to my son and so bought this little amp that is totally digital with bandtracks and modelling, etc. I have had the same heartaches trying to figure this thing out too as it's all menus and virtual stuff. It is a learning curve I didn't really want to waste my time on. I just wanted to play a tune.

[Steve Grisetti]

A guitarist, eh? Well, that's an even better metaphor!

I bought my first guitar about 10 years ago. Believe it or not, it was every bit as intimidating to me then as this program was to you!

After a couple of weeks, I'd built up some calluses, learned some basic chords and some notes and, of course, how to tune it.

But, funny thing, I still can't play like Angus Young!

As with any thing, you get as much out of it as you put into it. If you're happy playing playing simple songs using tabs you downloaded from the internet, you can probably get there in a month or two. But, if you want to be a real musician, you have to work at it, right?

And that's not Yamaha's fault for making my guitar, is it?

[braindeadsoftwareguy]

Steve,
A Yamaha guitar is different in that it is analogue The strings and frets are right there in plain sight and you just practice a physical motion. Software is hunting and guessing and strange terminology and too much hits and misses. Things like this:
I still haven't had an answer to why I cannot get my one image clip on the timeline to expand out to many frames? I have clicked until my face is blue on the little film frame icon, but it just toggles between the image and a blue background with a line. How would I ever edit individual frames if I can't do that?

I don't know what to index in your book to look up that question for myself.

[Chuck Engels]

I think Steve's Free Basic Training tutorial will help you out Guy
http://muvipix.com/products.php?searchp ... 12&btn.y=8

ib-Premiere Elements 8 Basic Training (8 parts)
Watch part 3

[Steve Grisetti]

No, it makes no difference that it's analog or digital. You have to learn that when you do certain things on a guitar it produces certain sounds. And even knowing that I still can't play like Angus Young. It's only easier to you because it's your world and you know it better than I.

Meantime, are you talking about changing the view of the video on your timeline? It's as we've said. You select the clip on the timeline and then you click the film icon on the track header to toggle through the views -- as in the illustration below.

[Chuck Engels]

I'm thinking that you need to zoom in on the timeline, if you are on the timeline.
If you are on the Sceneline view then you would only see one image, so you would need to switch to Timeline view. Steve's tutorial explains it all

[braindeadsoftwareguy]

No, it makes no difference that it's analog or digital. You have to learn that when you do certain things on a guitar it produces certain sounds. And even knowing that I still can't play like Angus Young. It's only easier to you because it's your world and you know it better than I.

Meantime, are you talking about changing the view of the video on your timeline? It's as we've said. You select the clip on the timeline and then you click the film icon on the track header to toggle through the views -- as in the illustration below.

My film icon will only toggle between the way your picture shows or without the scene showing and a line on a blue background instead. I discovered that if I grab the timeline image and drag it to the right, I will see all the scenes, but that slows down the playback in the monitor window? There is no mention right here of dragging the timeline, so why doesn't my clicking the icon, produce the example you've shown here?

Re: the guitar. My linear brain is making me have trouble expressing my thoughts on that. I'll give it one more shot. Instead of the guitar being in front of you, it is a virtual guitar program on the PC. The workspace looks nothing like a guitar, and without instructions (even though you can play a real one) you're expected to hunt and peck throughout the menus and unfamiliar icons to both tune and play the thing. That would be a more difficult learning for me than the real deal.