TOPIC
Sometimes when I play back a digital video (DV) clip that I captured with my DV camera, it appears blotchy, blocky, out of focus, and the colors are washed out. Why is this?
DISCUSSION
Reason: The process of decoding DV data, even over FireWire, requires large amounts of data and many computations. To maintain frame rate and view the movie at a normal size, only about one-fourth of the DV data is used in displaying the movie to the screen. However, the underlying DV data is still at full quality. Computer Display Solution : The QuickTime Pro-enabled QuickTime Player can be used to display a DV movie at High Quality. To do this, open the movie with QuickTime Player, and select Get Info in the Movie menu. In the Movie Info window, select Video Track in the left popup menu, and select High Quality in the right popup menu. Check the High Quality Enabled checkbox to view the movie at full quality. Frame rate will decrease substantially with this setting. The movie can be saved with this setting and from then on, when the Movie is played back in any application, it will be played at High Quality. In order to maintain full frame rate during the editing and playback of DV clips, Final Cut Pro, iMovie, and other QuickTime-based applications typically default to using Low Quality. The important thing to remember is that Low Quality is strictly a playback mode for computer monitors, and does not affect the quality of the DV image that is sent out through FireWire to the DV device or NTSC monitor. The Apple FireWire output is always High Quality. Note : NTSC is a set of standard protocols for television (TV) broadcast transmission and reception in the United States. NTSC Monitor Solution : If you are using a NTSC monitor to view the DV video during capture, you should see full-quality, full-frame rate video. However, if the video is choppy on the NTSC monitor you can determine if this choppiness is cosmetic or a symptom of actual frame loss. To determine this import the clip, then export the clip to tape and view it on a NTSC monitor. If the video is still jumpy on the NTSC monitor turn off AppleTalk and TCP/IP. Note : If you are using iMovie and you have 64 MB of RAM, enable virtual memory in the control panel. When using iMovie with more than 64 MB of RAM, virtual memory should be disabled. Other items that can cause choppy, jittery, or what may appear as dropped frames during video capture/playback: If these steps do not help then be sure to run through basic troubleshooting steps such as: |
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| Document Information | |
| Product Area: | Mac OS System Software |
| Category: | General OS |
| Sub Category: | General Topics |
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