Using the New Adobe MPEG Encoder


Before we get into the exporting/encoding details, I want to give you a little background on this new Premiere plug-in. To begin, select File, Export Timeline, Adobe MPEG Encoder.

Figure 20.1 shows the encoder's main interface. You'll note in the upper-right corner it says, " Powered by MainConcept." This is a long-standing German firm (from the days of the Amiga) with a solid reputation as a creator of powerful multimedia tools and codecs.

Figure 20.1. The new Adobe MPEG Encoder, "powered by" MainConcept.

As I mentioned in Hour 19, "Exporting Premiere Frames , Clips, and Projects: Part 1," including a software MPEG encoder in Premiere is a big deal . Up until now, if Premiere users wanted to create MPEG-2 videos , they had to buy a third-party plug-in, such as the $250 Ligos LSX-MPEG, or use a hardware encoder. Now Windows users get a powerful encoder for free . In a head-to-head competition with the Ligos encoder ( conducted by MainConcept), the Adobe MPEG Encoder came out on top in speed and image quality.

Its two-layer interfaceMain and Advancedmakes the most commonly used settings available in the main dialog box while giving "power users" the ability to tweak a variety of parameters in the Advanced dialog box. Another strength is its integration with Premiere and DVDit!, the DVD-authoring software I'll go over in Hours 2124.

MainConcept has a support/resource site for the Adobe MPEG Encoder. It includes a FAQ about the encoder and MPEG in general, new settings files to download, test results, and a link to the Adobe MPEG Encoder User-to- User forum on Adobe.com. The link to the support/resource site is http://www.mainconcept.com/adobempeg.html. You also can get to the Web site using a hotlink accessed by clicking the Encoder's About button.

MainConcept's Web site is worth a visit at the very least because it offers free "texture loops "four-second (1MB) motion video clips you can drop into Premiere for some dazzling background animation. Figure 20.2 illustrates how one looks. One use for them is as text backdrops.

Figure 20.2. Visit www.mainconcept.com to pick up a few texture loops like this one for use within Premiere.

It's a simple matter to copy/paste the same loop several times to create a smooth background animation. When placed end to end, there is a seamless transition from one copy of the clip to the next . You may also change the speed/duration of the clips to alter the character of the animations.


Task: Encode an MPEG-2 File

To export or convert a Premiere project or timeline segment to MPEG-2, follow these steps:

  1. For the moment cancel out of the encoder and go back to your timeline.

  2. Load a project and place the work area bar over a small segment15 seconds or so. No need to encode an entire project for this task. Despite MainConcept's successful speed trials, MPEG-2 encoding still takes about as long as the duration of your project.

    As a reminder, use the N hotkey to set the work area bar boundaries. Press N once, roll it over the work area, highlighted in Figure 20.3, and see which direction the triangle is facing . Click to set one endpoint for the work area bar, press N to switch the triangle's direction, and set the other endpoint. Press V to switch the cursor back to the Selection tool.

    Figure 20.3. Use the N hotkey to set endpoints for the work area bar.


  3. Select File, Export Timeline, Adobe MPEG Encoder to return to the MainConcept interface. Your first option is to choose an MPEG stream. The selections are shown in Figure 20.4.

    Figure 20.4. Select an MPEG "stream."

    Here's what these options mean:

    DVD Selecting this option means the MPEG Encoder will create two MPEG-2 filesone for video and the other audiofor inclusion on a DVD. DVDs can hold up to 4.7GB of data (133 minutes of MPEG-2 video) per side. You also can place VHS-quality MPEG-1 video on them. They play in both standalone DVD players and in computers with DVD drives .

    DVD is not an official acronym. Most companies say DVD stands for Digital Versatile Disc , but that's not the case. DVDs started as "digital video discs," but industry politics killed that idea. A journalist suggested "versatile" and through repeated usage that has become the de facto, standardized name .


    VCD (Video CD) If you select this option, the Adobe MPEG Encoder will make an MPEG-1 file of your project. Later, using standalone CD-authoring and/or writing software that supports VCD, you can "burn" up to about an hour of MPEG-1 video onto a CD that will play on most consumer DVD video players and computer DVD and CD drives. A good online resource for VCD and SVCD issues is http://www.vcdhelp.com/svcd.htm.

    The documentation accompanying the MPEG Encoder notes that DVDit! LE, the DVD-authoring product bundled with Premiere, does not support VCD creation. I tried running VCD (and SVCD) MPEG files in DVDit! and they both worked fine. The folks at Sonic Solutions, the company behind DVDit! tell me they have not run these file types through their extensive test matrix to check that everything works. It can sometimes be the case that such "untested" files will work, but Sonic Solutions cannot guarantee they'll work on every system.


    SVCD (Super Video CD) This is a step up from VCD. In this case, the Adobe MPEG Encoder will create a reduced bitstream rate, specialized MPEG-2 file. Depending on parameters you set, you can put up to about 45 minutes of video on a CD using this low-end MPEG-2 (still better than MPEG-1) video. Again, you need authoring- and/or CD-burning software that supports SVCD to create an SVCD CD-ROM.

    SVCD creates videos in a 480x480 resolution. If you play them back on standard video players such as the Windows Media Player or within Premiere in the Source window, they'll look "tall" (that is, squashed in at the sides). If you open these files in software that recognizes this standard MPEG format, such as DVDit!, they will play in the proper aspect ratio. If you place them on Premiere's timeline and play them in the Monitor window, they will display in the proper aspect ratio, but as noted later in the sidebar, "Why Premiere Does Not Edit Native MPEG Video," Premiere is not designed to handle any MPEG format.


    What about cDVD? Although DVDit! may or may not create VCDs or SVCDs, it certainly does create cDVDs. This is a Sonic Solutions proprietary product that puts MPEG-1 or MPEG-2 files at virtually any quality level on CDs that are playable on PC CD-ROM and DVD-ROM drives. When you use DVDit! to burn a file onto a recordable CD, that authoring product adds an MPEG player on the disc. That player runs directly from the CDnothing is installed on the user's hard drive. A cDVD should play smoothly on any Windows PC CD-ROM drive. The downside to this is that you cannot play cDVD discs in standalone DVD players.


    Advanced This option takes you to another interface that I'll cover in a few minutes.

  4. Select an MPEG stream. In this case, select DVD (MPEG-2). The default settings show up in the MPEG Settings Summary, shown in Figure 20.5.

    Figure 20.5. The MPEG Settings Summary displays the default settings for each MPEG stream.

  5. Select a video standard: NTSC or PAL.

  6. In Output Details, shown in Figure 20.6, you can give your file a name and a file folder location.

    Figure 20.6. Output Details is used to set the filename, location, and other basic options.

    If you plan to use DVDit! to create DVDs, then check the Save to DVDit! Media Folder box. That automatically places the folder name in the Location window. If you want to launch DVDit! after the export, check that box as well.


  7. As you did with the Export Movie Settings dialog box, choose an export range: Entire Project or Work Area.

  8. Finally, select the Fields option. This is something of a hit-or- miss proposition. It sets the so-called field order or interlace . Most DV starts with Lower Field First, but analog capture cards can use Lower or Upper Field First.

    If you're unsure about the Fields setting, select No Fields to produce acceptable but not optimal video. The workaround is to experiment by creating a file with one setting and watching the clip to see whether it's jittery. If so, switch settings.


  9. Click Export.

The MPEG encoding begins. Because you accepted the default settings, the Adobe MPEG Encoder compresses more or less in real time (that is, it takes as long to encode as the length of your project). In this case, it takes about 15 seconds.

To view and listen to your newly created MPEG-2 files, you may import them to your Project window or open DVDit!, start an MPEG-2 session, and view them in its window.

Just to make sure all is in order, import the video and audio files into Premiere and drag them to the timeline. Place the audio directly under the video and link them together.

As a reminder, the Link tool hotkey is U. (You may need to cycle through the Crossfade and the Fade Adjustment tools first.) Once it's selected, click both the video and audio clips to link them.


Advanced Interface

Accepting default settings for any of the three MPEG stream types may be all you'll ever need to do, but the more you use this encoder the more likely you'll want to fine-tune it. Here's how:

  1. Open the MPEG Encoder again by going to the main menu and selecting File, Export Timeline, Adobe MPEG Encoder.

  2. Click the Edit button next to Advanced in the MPEG Stream section. That opens the Advanced MPEG Settings dialog box, shown in Figure 20.7.

    Figure 20.7. The Advanced MPEG Settings dialog box lets you fine-tune your MPEG encoding process.

There's no need to click the check box next to Advanced in the MPEG Stream window. Doing so keeps the current default settings in the Settings Summary window.


The depth of customizability in this interface is remarkable too much to discuss in detail here. Of the five tabs, you may never access more than two: Basic Settings and Multiplexer Settings. Here are some highlights:

Basic Settings This is one of the simpler of the settings pages. Select the preset drop-down list and note that half (nine) are for NTSC and the other half for PAL. Three are for 16:9 (wide-screen) aspect ratios; the rest offer higher or lower bitrate settings than the default presets:

  • Video Type provides a simple way to revert to the default settings for an MPEG stream.

  • Video Bitrate adjusts the maximum bitrate.

    The bitrate settings are generally safe to adjust when encoding for DVD only.

    VCD and SVCD High Bitrate CBR (Constant Bitrate) have very narrow allowable bitrate values. Parameters need to be within the legal limits for the format. The Adobe MPEG Encoder will present warning messages when invalid settings are chosen .


  • Encoder Quality means the lower the quality the faster the encoding.

The Video Encoder Quality slider controls a few different parameters that tell the encoder how big of a search area within each video frame to examine for matching blocks of pixels. The surprising thing is that with many videos you can turn the slider down significantly (resulting in faster encoding) without any noticeable quality loss. For general use, a Video Encoder Quality setting of 28 will usually provide a very happy medium of fast encoding and great quality. See Advanced Settings, later in the list, for additional Video Encoder Quality tips.


DVDit! LE does not support 16:9 screen widths. The Adobe MPEG Encoder does. Adobe included this option in the encoder in case you have other authoring software that works with 16:9. DVDit! PE (Professional Edition, a $500 upgrade from DVDit! LE) does.

Selecting a high bitrate means you will experience long encoding times. Use this only to preserve high-quality video or film images.


You may load presets obtained from other sources into the MPEG Encoder. The MainConcept/Adobe support Web site will be one source. Simply download themthey're small filesand use the Load button to select them. If you want to add one to the Preset drop-down list, save it to the default Settings folder.


Video Settings This page offers up some complexity, including GOP (Group of Pictures) settings, and is only for those who are steeped in MPEG arcana.

Advanced Video Settings Even the folks at MainConcept make a point of admonishing Premiere users to forgo this collection of complex selections. Unless you're dripping with knowledge about ITU-R Rec, 624-4 System B, and G matrix coefficients, take a pass (with two exceptionssee the following tip).

If you adjusted the Video Encoder Quality slider, you may want to fine-tune that by tweaking two values in the Advanced Video Settings page:

Motion Search A setting of 5 to 8 is appropriate for most material. 5 provides faster encoding but with the potential for quality loss (although at higher bitrates or in material with low movement, this potential is reduced significantly).

Noise Sensitivity This control sets a motion search threshold, depending on the noise in the video. The noisier the video the higher this should be set, but it generally is not advisable to go over 15. The higher the setting, the faster the encoding. Here are some recommended values:

  • 05 for material with no noise at all, such as computer animation

  • 39 for material with nearly unnoticeable noise (such as DV)

  • 713 (or higher) for material with high noise, such as TV capture


Audio Settings Same story here. Unless you have a specific need to change the audio frequency, type, or bitrate, skip this page.

Multiplexer Settings This is the other page you may want to access. As you noted when you created the MPEG-2 video (by selecting the DVD MPEG stream), you ended up with two files: video and audio. This page, shown in Figure 20.8, lets you multiplex (combine audio and video into one file). That means software such as Windows Media Player and RealOne Player will play audio while playing video. Of the three MPEG stream types, only DVD does not multiplex by default. To change that, simply select MPEG-2 from the Multiplexing Type drop-down menu. I've highlighted that in Figure 20.8.

Figure 20.8. Selecting MPEG-2 in the Multiplexing Type drop-down list combines video and audio into one MPEG-2 file.

DVDit! can work with multiplexed (or muxed ) files. But it works more efficiently with "elementary stream" (separate video and audio) MPEG files.


Why Premiere Does Not Edit Native MPEG Video

As I put together this hour on MPEG encoding, I swapped several emails with the MainConcept U.S. subsidiary Chief Operating Officer, Mark Bailey.

Bailey is the company's primary liaison with Adobe. His solid grasp of the MPEG compression universe completely impressed me. After reading several emails from several Beta testers on the Premiere forum asking why Premiere didn't offer MPEG editing, I asked Bailey for his take on this topic. The remainder of this sidebar summarizes what he had to say.

Although MPEG is an excellent way to deliver material, it has some limitations as an editing format. Because of its high compression and the way that some frames are calculated, MPEG material can be subject to significant quality degradation when rendered multiple times. Because video editing and compositing projects often involve many generations of rendering, there is the potential for noticeable loss.

Of course, it's best to start any editing or compositing project with the least-compressed source material available. Using highly compressed media from the start could present serious problems.

The workflow explained in this bookediting in DV and encoding the finished project to MPEGworks very well.

There are some cases in which people might need to edit MPEG, and some companies offer plug-ins that enable it with varying results. Of course, MainConcept could create a superb MPEG-editing plug-in, offering the best possible results given the nature of the format. Even so, editing MPEG still isn't the best way to go in many cases.

One of the most popular arguments for MPEG editing is to save the time-consuming process of MPEG encoding. However, in our tests the Adobe MPEG Encoder is running at nearly real-time on a 2.2 GHz Pentium 4 system. Therefore, MPEG encoding is not the lengthy ordeal it once was, and it will be even less painful as CPU speeds continue to increase.



Sams Teach Yourself Adobe Premiere 6.5 in 24 Hours
Sams Teach Yourself Premiere 6.5 in 24 Hours
ISBN: 0672324288
EAN: 2147483647
Year: 2002
Pages: 249

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