Final Cut Studio: August 2008 Archives

During Editing

You've laid down your sequence, you've got your clips sounding consistent relative to each other - now you should check for peaks.  In Final Cut, this is as simple as picking Mark Menu -> Audio Peaks -> Mark.  Markers will appear above the sequence anywhere there's a peak.  Now, you could just pot down the gain on those clips, but if you do that you'll lose the consistency between your clips' audio levels.  So instead, you can hack out the individual peaks themselves.

You can do it by hand, or you can do it with a single step in Soundtrack Pro.  Read on ...

During Shooting

The first step comes while you're producing your footage in the first place: if you happen to be a one-man show and you're doing your own taping, be absolutely sure to check your audio levels on your camera as you're shooting.  Most cameras can be set up to show some kind of audio meters on their display; as a last resort, though, almost all will let your plug in headphones and listen for gross distortion.

Ever seen your audio meters go into the red?  Marked those unsightly peaks in your audio?  Heard the raging distortion that happens when somebody shouts into a mic?

Creating a photo montage to the beat of music in Final Cut Pro can be much easier with a couple simple steps. The first step is to establish the beat of the music. Before doing this you will want to make sure your audio is ready for Final Cut. Once in your sequence you will want to set markers in the audio track to the beat of the music. By playing the music, and hitting the "M" key to the desired interval, you will create a template for your montage. If you have limited ability in this regard, another option is to load the audio into the Viewer, and apply the Markers visually, by looking at the wave form in the Audio Tab.

Application: Fonts and Vector Images
Antialiasing also has something to do with why fonts and vector images always look good, even if they're really big or really small.  Actually, fonts are vector images, so that's a bit of a strange thing to say - but at any rate, vector images are simply a set of mathematical equations that describe the curves that make up a shape.  So, like the real world, the computer can "look at" these images with infinite precision.  Therefore, it knows enough about the shapes to behave like our eyes do, and approximate the way we would see the fonts and such if they didn't have to be on a quilt of pixels.

Application: Photoshop
One place where this knowledge might help you think is in Photoshop, especially if you're designing for compositing software or DVD production.  Say you're doing a glass bug for your video: did you notice the anti-alias checkbox when you used the Magic Wand tool?  That checkbox means that the computer will actually select fractions of pixels on the edge of the selection it shows - "blurring" the selection boundary in the same way that it did to the red channel in the example reproduced below.

We know antialiasing best as "smoothing" the jagged edges that any digital editor will eventually happen across.  Why do we need to antialias, and where do aliasing artifacts come from in the first place?  The answer is a little mathy, but we'll bring it down to size.

Masks vs. Alphas

Alpha channels are our most sophisticated way to handle transparency, but they're by no means the only way.  We commonly use the term "Mask" to refer to something similar to the alpha channel above - that is to say, a full range of "see-through-ness" for each point.  Photoshop, for example, uses the term "Mask" to mean just that.  But more primitive incarnations of "image masks" in applications like DVDs and some still image files like GIFs use a different approach.

Whether you're using titles, creating supers, or doing any other sort of compositing, you're trying to tell the computer to show some parts of an image but to hide other parts.  

I've been surprised by the number of folks who were never really taught how that process works from the computer's point of view.  After the jump, an easy little primer that may help you understand --

To avoid any issues with your audio, you will want to convert your audio files to AIFF. An easy way is to export using the Quicktime Conversion.  I had always done this in iTunes, but just discovered an easier way.

I locate the audio file I need in the finder, and drag it into the Viewer. If you don't know where it is, use the Spotlight to locate it. Once your audio file is in the Viewer, you will Export Using Quicktime Conversion. This is a good function to map to a key, because we are often exporting thru the Quicktime Conversion. When the Quicktime Conversion window pops up you will want to choose the location you want the converted to go to, and change the Format from Quicktime to AIFF.

When iTunes did the conversion it would put the converted file into the same folder the source was from. Using this method we can skip the step of moving the file from where it was saved to our Project Folder.

When using a still image in Final Cut Pro, consider down sizing the image based on the application. For example if you are using a 3456 x 2304 (8 Megapixel) photo in a DV sequence (720 x 480) then Final Cut needs to do the scaling. If you were doing a photo montage with 200 pictures, this would cause a serious slow down in performance, and you would have plenty of opportunities to stare into the spinning beach ball.

Depending on how much you are planning to zoom in on an image, you will choose the size to reduce to. If you are working in a DV sequence and not zooming in on the photo at all, or applying a subtitle Ken Burns effect setting the height to 700 will provide a 1050 x 700 image. which will work great. When working in an HD sequence size your pictures to a height of 1500, which will give you a 2250 x 1500 image. You can do the down sizing using iPhoto, Aperture, Photoshop, or many other applications. You can export 1 image, or an entire folder of images.

Not working with images larger than they need to be is certainly a easy way to increase your productivity with Final Cut Pro.

This time, we'll write a script to detect whether the DVD player is showing in widescreen (16:9 anamorphic) mode or standard (4:3) mode - and automatically play the video in the appropriate format.

I hope that this tutorial will be a practical one for those of you who are putting both regular NTSC-DV content and anamorphic on the same disc, but more importantly I hope that the introduction to bit math might be useful if you need to extract other characteristics from the bitwise SPRMs, like SPRM14 (Video Config), SPRM15 (Audio Config), and SPRM11 (Karaoke).

You'll have to excuse me for getting all technical up in here; "bitwise" just means that the single SPRM stores a lot of pieces of information in one number. Read on for what I promise will be a painless introduction ...

Let's say your title is a bit ... racy. And maybe, because you're a good citizen, you don't want it to play on sets where parents have enabled parental control.

Using DVD Script, the solution is surprisingly simple. First, create a script - call it, say, "Verify Parental Controls" ...

Finally, a practical example! And we won't even need all the SPRMs or most of the GPRMs from last time as we create a video that plays its tracks in random order.

In fact, we'll only use a single GPRM - those are the variables that are ours-all-ours, remember? - plus a jump or two, a little math, and the conveniently-named Set GPRM Random command. Let's say you have four tracks of video, and you want them to cycle randomly ad infinitum - maybe you're at an exhibition or something, who knows.