QuickTime
You can start by making a new QuickTime preset from the Action popup, selecting New Setting, and then QuickTime Movie from the drop down sheet. Many of the QuickTime controls are the same as we’ve just seen, except that the default Frame and Frame rate are both set to Automatic. The real difference is in QuickTime settings, which defaults to Apple ProRes 422 HQ and is probably too high for anything that’s 1080 or smaller. If you click the Change button the QuickTime settings sheet will drop down. At the top is the Compression type popup with a huge list of available codecs (see Figure 19), including a long list of XDCAM compression types too long to show. Unless you have specific requirements for one of the many codecs such as an IMX codec, you probably should focus on the ProRes group or H.264 or x264, which is an open source variant of H.264 which you can download that produces better results for smaller file size.
Figure 19 QuickTime Codecs
If you need to carry a transparency channel with your video, there are a few codecs that do that, the old Animation codec at the top of the list, ProRes 4444, and ProRes 4444 XQ. If you select one of these and want to preserve an alpha channel make sure the Compressor Depth popup is set to Millions of colors+, the + being the alpha channel. If you don’t need the alpha and still want to use these very high quality, lossless codecs, then simply set it to Millions of colors.
Let’s look at setting up a preset for the web.
- • Using the basic QuickTime Movie setting, first in the General pane select video, audio or both. Switch off audio if you don’t need it.
- • In the Video pane set the frame size you want, for instance up to 720 or up to 1080.
- • Leave Frame rate on Automatic. It will not make much difference to file size because of the way modern codecs work.
- • Make sure Field order is set to Progressive. Never use interlaced media on the web.
- • Click the Change button for QuickTime settings and in the Compression Type pop-up select either H.264 or x264 for the web.
- • Never use Automatic for the data rate. Nor should you use the Quality slider. Always dial in a number in the Data Rate box. The higher the number the larger the file size will be, but the quality will be better. The larger the frame resolution the higher the data rate needed to maintain the quality.
- • For HD video for the web at 720p never use less than 1200 or 1400 kbps. For standard definition, 640x480, you can go down to 1000kbps. For smaller files like 480x360 you can go as low as 600 kbps.
- • For 720p a setting of 6-8000 kbps usually works well and for 1080p 10000kbps is plenty, and 8000 kbps is usually quite sufficient. You can use lower numbers with x264.
- • If you use H.264 you can set the Optimized popup to Streaming. You can’t switch this with x264.
- • Keyframes should be set to three to five times the frame rate of the output. With more action make the keyframes closer together, so set to three times the frame rate, for talking heads use five times the frame rate. The more keyframes used the greater the file size.
- • Frame Reordering should be checked on.
- • Encoding should be set to Faster encode (single-pass) unless you have complex media.
- • As you’re making video for your web video that will be seen on both Macs and PCs, in the Video pane you should use the Gamma Correction effect to make a small adjustment to the video that will be a good compromise for the different systems. Make the gamma (the midtones gray point) a bit darker by setting it to 1.05.
- • To improve the saturation of the video for web display, set the Color Correct Midtones filter to increase all three: red, green, and blue, by +3.
- • In the Audio pane for many jobs, especially for video with speech only, setting the audio to Mono will work as well as Stereo and will save some file size. For files with music you’ll want Stereo.
- • Set the Rate to 48K or 44.1, CD quality. For files with speech and natural sound only, you set it down to 22K. This will also reduce the file size.
- • Leave the Sample size at 16-bit.
- • Click the QuickTime settings Change button and set the format to AAC (see Figure 20).
- • When using AAC Mono at 22K, set the Target Bit Rate to 40. Otherwise, leave it at 128 for Stereo 48 or 44.1K.
Figure 20 Sound Settings
Before you output your file, in whatever compression setting you’re using, always, always test a short section, about 10 to 30 seconds, to see how your encoding will work. Use the In and Out points in the Viewer to select a section that has the most movement, or has the most complex images, or has transitions, such as cross dissolves, which are very difficult to encode well. Once you’re satisfied with the test results, you can encode the entire file.
Active Window
The Active window, which you’re automatically switched to after you click the Start Batch button in the Current window, gives you information about the encoding process.
Droplets
A Droplet is a tiny application that lets you apply a compression setting to a media file. You can put the Droplet anywhere you want. Usually you just leave it sitting on your desktop. You can make any preset, Apple or custom, into a Droplet. Simply right-click on it and from the shortcut menu select Save as Droplet. With a setting selected you can also use the Action popup at the bottom of the Settings pane.
In the drop down sheet give your new Droplet a name, something useful, like what settings the Droplet applies to your media (see Figure 22). Select where you want to save the Droplet, and select the Location folder for the output files.
Figure 22
To use a Droplet Compressor does not have to be running, nor does the application even launch when using a Droplet. Simply drag the files you want to compress onto the Droplet. The Droplet window will open, which allows you to confirm the setting and the output location.
With the Droplet window open, you can add more files to the job, simply by dragging them into the pane.
Job Chaining
Job chaining allows you to use the output of one compression job as the source file for subsequent jobs. I’m not a great fan of this feature as it means you’re double compressing your media, but sometimes it’s very useful, for instance if you have an H.264 file and you want to make a ProRes master from it and then compress a low res web version from that.
To create a job chain, import your master file and apply your master file setting. For instance you might select the Apple ProRes 422 HQ preset to create your master file. Then with the setting applied to the file, right-click on it and from the shortcut menu select New Job from Selected Output (see Figure 23). This will produce a new job with a chain link icon to which you can add whatever settings you want.
Figure 23 Job Chaining
Preferences
Compressor has some important preferences for you to set up, especially if you want to use distributed processing, having your media be processed by multiple machines to speed up your work. The preferences are of course in the Compressor menu. The first pane gives General preferences, the default setting, the default location, and the application behavior once a batch is started (see Figure 24).
Figure 24 General Preferences
The My Computer preference pane simply allows you to switch on your computer to be part of a distributed network and to add a password if you wish. The Shared Computers preference lets you add computers on your network to use for your distributed processing (see Figure 25).
Figure 25 Shared Computers
For distributed processing each of the computers needs to have Compressor installed, and they all need to be connected on a fast Ethernet network, not WiFi, which is too slow to be of value. You also need to ensure that in your General settings for each job you have checked on Allow Job Segmenting.
That’s it for our quick look at the latest version Compressor! I hope you found it useful and get a lot out of working with the application.
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