Subtitles of the Movie

In this tutorial we're going to talk about Progressive and Interlaced Scanning, and these are two different ways of displaying video. When video is displayed it's displayed one line at a time, and each one of these lines is called a Scanline, and they're displayed very quickly to create the illusion of a complete image. In Progressive Video, the scanlines are displayed just from top to bottom, 1, 2, 3, 4, 5, 6, 7 and so on. In Interlaced video, the lines are divided into two groups: the odd lines and the even lines. Each of those groups is called a Field and it displays one field first, let's say 1, 3, 5, 7, and so on, all the way to the bottom, and then the other field; in this case, 2, 4, 6, 8 and all the way to the bottom. So it takes two fields to make up a complete image, one frame. So let's see how this could affect you when you're creating video for Flash. Computer screens are designed to display Progressive video, so if you try to display interlaced video on a computer screen you're likely to get artifacts. This is an example of that; this is an Interlaced Video. If you look here outside the hair, you see sort of a shadow that's actually kind of a cone pattern, and what happened there is one field was displayed, but before the other field could be displayed she moved, and therefore you only get one field shown here. You get the same thing right here just above the shoulder. This is an FLV created from this. When this FLV was created, the Adobe Media Encoder automatically de-interlaced this when creating the Progressive video, so those artifacts are no longer there. So, let's take a look at this in the Media Encoder. So, here's that file in the Media Encoder. Let's double-click, go to the Export Settings. Right now we're set up for FLV. You won't see anything here about Progressive video, or interlacing, or de-interlacing, because it simply assumes that you want Progressive video, and it automatically de-interlaces where necessary. By the way, these artifacts here are in the original. It has nothing to do with interlacing or de-interlacing. In the previous version of the Media Encoder for CS3 there was actually a box for de-interlacing, but now it's done automatically where appropriate. For F4V you actually have an option to choose Progressive or two forms of Interlaced: Upper field first or Lower field first, but you almost always want to use Progressive and in fact, every Preset for F4V chooses Progressive, even, for example, when it starts with an NTSC Source, which is probably interlaced. So, interlacing shouldn't really cause you a lot of problems when you're working with the Media Encoder because it takes care of it automatically. But if you ever run into a situation where you're seeing artifacts like this, know that you're probably trying to display interlaced video on your computer screen and you need to de-interlace that video and create a Progressive video that will display properly on your computer. And that concludes this tutorial on Progressive and Interlaced video.