83 Deinterlacing Video for Progressive Output

#83 Deinterlacing Video for Progressive Output

Most video acquisition formats like DV and the 1080i HDV codec used by the Sony and Canon HDV cameras are interlaced formats that contain two fields for every frame, usually shot 1/60^th of a second apart (1/50^th for PAL). In contrast, most streaming formats are frame-based. To produce frame-based video from interlaced sources involves combining the two fields into a single frame, which can produce the artifacts shown at the top of Figure 83a.

Figure 83a. The top frame sample is not deinterlaced; the bottom sample is.

Deinterlacing Large Projects

If your project has multiple video files, or multiple sections of the same video file, you have to deinterlace each instance on the timeline. If your project includes hundreds of files on the timeline, it may be faster to output the entire project into one file in DV-AVI format, then deinterlace that file before outputting into your final format.

To avoid artifacting and produce video more like the bottom of Figure 83a, you have to tell Premiere Pro to deinterlace the video. Here's how you do it:

1.	Right-click the video source on the timeline, and choose Field Options from the pop-up menu. Premiere Pro will open the Field Options dialog box.
2.	Select the Always Deinterlace radio button (Figure 83b). Figure 83b. Choose Always Deinterlace to deinterlace all frames in a clip bound for progressive streaming formats.
3.	Click OK to close the dialog box and render your video. Note Selecting the Deinterlace checkbox in the Output tab of the Export Settings dialog box (Figure 83c) doesn't deinterlace the footage; you must deinterlace it on the timeline. The Export Settings preview screen does provide an accurate preview, however, so if your video isn't deinterlaced there (as shown in Figure 83c), the final file won't be deinterlaced either. Figure 83c. As you can see, selecting the Deinterlace checkbox doesn't resolve the problem, as the deinterlacing artifacts are still evident.