Cropping an image with Vegas Pro
by Gary Rebholz
The Event Pan/Crop tool that you find on every video event in your project gives you a lot of power to adjust the look of your video. You have probably used this tool to create zooms and panning moves on still images or even on video clips to emulate moves that the camera operator didn't shoot. This technique is becoming even more useful with the advent of higher and higher resolution footage.
You may not have realized that you can create true cropping with the same Event Pan/Crop tool. By this I mean that you can crop, or cut off, the edges of an image to remove something from the scene. This involves setting the tool up so that the image is not stretched to fill the frame when you change the size of the position box. In this article I will show you how to create this type of true cropping with the Event Pan/Crop tool.
Every video event in your project (whether it holds a video clip, a still image, or generated media) contains its own Event Pan/Crop controls. I'll use an event with a video clip in it to demonstrate. Click to place your cursor within the clip you're going to be working with so that you can see the clip in the Video Preview window. Then, click the Event Pan/Crop button. Sometimes the event is so small on your timeline that there isn't room to display the button. In those cases, right-click the event and choose Video Event Pan/Crop from the menu. Both of these techniques open the Event Pan/Crop window, shown in Figure 1.
The dotted box with the big F in it is called the position box. As an aside, to answer a common question, the F really has no significance other than that it shows you the orientation of the box. Since you can rotate, move, and flip the box, you could easily get confused about its orientation if we didn't supply the F as an orientation reference.
I want to use the rocks along the bottom of my image as a background for a lower third, so I'll need to crop the picture down to just the portion I want to use. First though, let's take a look at how the tool works with its default settings.
Position the Event Pan/Crop window on your screen so that you can see the Video Preview window at the same time. Now you can monitor the results of the changes you're about to make. I'll assume that you haven't changed any of the window's default settings. Drag one of the position box's corner points toward the center of the box and notice three important things as you do so.
First, as you drag the corner point, you realize that you cannot change the shape of the position box. No matter how you drag the point, the height and width of the box always remain in proportion. In other words, the box's aspect ratio is locked and you can't change it, even if you drag one of the side points instead of a corner point. That aspect ratio matches the aspect ratio of the media that the event holds.
Next, as you drag the point to resize the box, you see that the position box's center remains the same. As you drag toward the center, you create an ever smaller box whose center does not change. You see a dot in the lower horizontal bar of the F. That dot sits at the exact center of the box. Its main function is that it serves as the rotation anchor around which the box rotates when you change its rotation angle.
And finally, I want to point out what's happening in the Video Preview window as you resize the position box. As you make the box smaller, you change what appears in the Video Preview window. Only the portion of the clip that remains inside the box in the Event Pan/Crop window appears in the Video Preview window. Since that portion of the image doesn't fill the video frame at its regular size, the tool stretches that portion of video to fill the entire video frame. In other words, it enlarges the portion of the video that falls inside the position box to fill the entire frame. That's how you create a zoom that wasn't originally shot on camera. Of course, once you've changed the size of the position box, you can move it to zoom in on whatever specific area of the video frame you want to. Figure 2 shows my position box in the upper-left corner of the frame and the resultant zoom in the Video Preview window.
While this is a great technique and very useful in many situations, it doesn't give us what we want in this case. What I wanted was to crop down to just a strip of the rocks to use as my lower third, so we'll have to makes a few changes to the Event Pan/Crop window's default settings. Let's start by putting things back the way we found them so that we can start fresh. Right-click the position box and choose Restore from the menu. This sets the box back to its original size and position and you once again see the entire clip in the Video Preview window.
In order to have full control over the area you want to crop, we can change settings in the Event Pan/Crop window that address the three points I mentioned earlier. First, recall that as you move a point in the position box, the box's aspect ratio always remains the same. In order to accomplish what we want, we'll have to change the box's aspect ratio. To do so, click the Lock Aspect Ratio button to disengage it.
Next, it's helpful to be able to work with just one side of the box while you're setting your cropping, but you can't do that currently because as you saw earlier, the box's center always remains the same. But, of course, you can override that too. Click the Size About Center button to disengage it.
Now, drag one of the corner points to make the box smaller. You see that now you can change the aspect ratio of the position box and also that only the two sides of the box connected to the corner point move. The other two sides remain in their original positions. Right-click the position box and choose Restore again.
Since we want to crop down to a section that stretches all the way across the Video Preview window for our lower third, we want to crop out some of the top of the image as well as the bottom. So, drag the top midpoint down and the bottom midpoint up. Figure 3 shows my Event Pan/Crop window after I do so.
We're almost there. But look at your video preview window. Mine is shown in Figure 4.
You can see in the Video Preview window that you don't have exactly what you wanted yet. Recall the third point about changing the position box that I discussed earlier. That is, the Event Pan/Crop tool is always going to stretch the image within the position box to fill the entire frame. Remember, that's how we created the zoom effect earlier.
It's the tool's attempt to do so that causes the area you selected to be shown across the middle of the Video Preview window instead of in the natural position of what you chose in the position box. Compare Figures 3 and 4 to understand what I mean. The tool is attempting to stretch the image within the position box to fill the entire frame (using the center of the frame as an anchor point), but by default it won't distort the image, so it'll only stretch until it reaches the limits of either height or width. In this case, it reaches the width limit first, so you see empty space above and below the selected area.
To override the tool's default instructions to stretch the image to fill the frame, click the Expand button for the Source heading in the properties section of the Event Pan/Crop window. Then, change the Stretch to fill frame property setting from Yes to No. Now you can see in Figure 5 that the position of the selected portion in the Video Preview window exactly matches that of the position box in the Event Pan/Crop window (refer back to Figure 3). Just as we wanted!
Back in the Event Pan/Crop window, make more adjustments to the size and location of the position box. As you do, you see that you are literally showing the exact area of the clip that falls within the position box and hiding anything that doesn't. That's true cropping.
If you want to watch as I go through each of the steps in this article, check for the next video in the free video tutorials hosted by Les Stroud. Also check out our other free training videos and other training resources at http://www.sonycreativesoftware.com/training.
Gary Rebholz, is the training manager for Sony Creative Software. Gary produces the popular Seminar Series training packages for Vegas Pro, ACID Pro, and Sound Forge software. He is also co-author of the book Digital Video and Audio Production. Gary has conducted countless hands-on classes in the Sony Creative Software training center, as well as at tradeshows such as the National Association of Broadcasters show.