The most popular video format on the Internet is QuickTime; the video quality is excellent and all users have to do to watch QuickTime videos is download and install the QuickTime player, which is free.
With the ever-increasing speed of Internet connections and the efficiency of video compression, we are enjoying unprecedented opportunities to showcase videos on the Internet. This article deals with how to encode a video file in the QuickTime format for use on the internet.
Encoding video with QuickTime Pro: the video settings
1. Buy QuickTime Pro and install it on your computer. Export your video from your editing program as an AVI file or something similar, and open the video in QuickTime Pro.
2. Go to the File tab and click on Export. In the export field, select Movie to QuickTime movie.
3. Click on Options. This will take you to the Movie settings panel of the QuickTime encoder. Under Video there are three tabs: Settings, Filter and Size.
(a) In the Settings tab you choose the codec: Sorenson Video 3 is an excellent codec, and the new h.264 is even better. Select the frame rate: 29.97 fps for NTSC video, 25 fps for PAL video – in theory you can reduce the frame rate to make the file size smaller, but if there is significant movement in the video this will result in jittery motion.
Now select the quality: the higher the quality, the larger the resulting QuickTime video file and the longer users will have to wait before they can watch your video, so choose wisely. It is generally a good idea to have two or more versions of the video: a large one aimed at users with broadband internet, a small one for those on slower connections and possibly a medium one. Remember that the smaller the frame size of your video, the lower the quality of the video can be without anyone being put off.
Now select the keyframe rate: one keyframe for every 300 frames in NTSC video and one keyframe for every 250 frames in PAL video generally works well. If you find that the image breaks down in between cuts, you might have to use more frequent keyframes, but this will be at the expense of the video’s overall quality, as fewer bits will be available for all other frames.
(b) The Filter tab has options such as brightness, contrast, alpha gain, color adjustment, blur and special effects such as film grain and lens flare. QuickTime compression tends to darken the video slightly, so you may have to compensate for this using the brightness adjustment tool.
(c) You now adjust the frame size. Make sure that the frame size you select is consistent with your video’s aspect ratio. Also, the height and width of the frame should ideally be divisible by four or, even better, by 16.
The bigger the frame size, the larger the Quicktime file will be. The optimum compromise between video quality, frame size and file size is generally found by trial and error.
Tweaking the audio settings is much simpler. A compressor that yields excellent results is the IMA 4:1 compressor. You then have a choice of sample rate (between 8000 and 48000 kHz) and sample size (8 bit or 16 bit), and between mono and stereo. Again, the better the quality of the sound, the bigger the QuickTime file will be. Mono at 16 bit and 32 kHz is a good compromise, but you may decide that stereo is important to your viewers’ experience.
If you want users to be able to start watching the QuickTime video before it has all been downloaded, check the “Prepare for Internet streaming” box and select “Fast start” from the menu. Using the fast start option is highly advisable, because without it users will not see anything apart from the QuickTime logo until the whole video has downloaded, and many people can become discouraged and give up before your video has started playing.
Click on OK. This will close the settings box. Type in a file name for your video and click on “save.” The QuickTime encoder will start compressing your video.
You will probably have to repeat the process several times with different settings in order to find the best compromise between frame size, file size and image quality .