Adobe Premiere Pro 2.0 [Electronic resources]

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Using the Adobe Media Encoder

The Adobe Media Encoder is an export powerhouse tool that has been completely redesigned for Premiere Pro 2.0. It offers several flavors of MPEG encoding plus Macromedia Flash Video, Windows Media, RealMedia, and QuickTime streaming media (as opposed to the QuickTime MOV files you encountered in Export Audio and Export Movie).

Each of the five encoding engines has so many presets that few editors will need to do any parameter-tweaking. That said, there are customizable options aplenty.

Rather than attempt to explain each encoding engine's unique characteristics, I'll show you how to access them and explain a couple of general concepts. For detailed explanations of all the options for each encoder, open Premiere Pro Help and go to Video Output > Adobe Media Encoder.

Select File > Export > Adobe Media Encoder.

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The Adobe Media Encoder consists of a preview display on the left, and tabbed panels containing export settings on the right. In the preview display you can choose to view either your source or output video. The Source tab displays your sequence before any export settings have been applied. The Output tab shows how your video will look once it's exported.

A time ruler lets you scrub through your video. You can crop the source video using the Source display or switch to the Output display and deinterlace.

Note

Use the Deinterlace option if the video in the sequence is interlaced (all standard DV is interlaced) and you are exporting to a non-interlaced medium, such as progressive scan video. Interlaced video displays images in fields of odd-numbered, then even-numbered, horizontal lines. NTSC displays in 29.97 frames (or 59.94 fields) per second.

Export settings

When setting export options, you can choose from a number of presets or create your own custom settings. Custom settings can be saved as presets for future use. As you make changes to your export settings, the Output tab in the preview display updates to reflect your changes.

Adobe Certified Expert exam objective

Given a format, explain how to use the options available from the Export Settings panel when exporting from the Timeline to the Adobe Media Encoder.

Macromedia Flash video

Macromedia Flash Video is based on Flash Player technology so it's ready to play on any PC with a Flash-enabled browser. You don't have to worry about the platform or the format. With Flash Video, when the page loads, the video plays.

1.

Select Macromedia Flash Video from the Export Settings > Format drop-down list. Of the five encoders, Flash Video has the fewest options.

2.

Click the Video tab (below the Export Settings panel) and click Options.

3.

Choose an encoding profile from 150 kbps to 700 kbps. If you click Show Advanced Settings you can adjust the frame rate and frame size as well as a couple of other options.

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QuickTime

QuickTime offers the most options, but has a limited number of presetseight each for NTSC and PAL.

1.

Select QuickTime in the Format drop-down list.

2.

Select QT 256 Streaming NTSC from the Preset drop-down list.

3.

Open the Video tab, click the Video Codec drop-down list and note that as with QuickTime's Export Movie option, you can select from a list of more than 20 codecs. Several have additional options.

4.

Click the Audio tab and note that the options there are similar to those you encountered in the Export Audio option.

RealMedia

RealMedia takes more of a consumer-friendly, hand-holding approach and offers the fewest user options. Its collection of presets is similar to those in QuickTime with the addition of one for 24P (film frame rate) video.

1.

Select RealMedia.

2.

Click the Audiences tab.

This is where you can customize the bitrate from the selected preset and choose one- or two-pass encoding. Both RealMedia and Windows Media offer this option. If two-pass encoding is selected, the encoder analyzes the original video project before transcoding it. Encoding will take almost twice as long, but the resulting video will look better than a single-pass version using all the same parameters.

Windows Media

This is the most versatile video format for use in Windows PCs and for playback on the Internet. You can create single files with multiple bandwidth bit-stream rates (as a means to compensate for varying Internet user connection speeds), or you can create high-definition, wide-screen videos with 5.1 surround sound for playback in theaters or on HD TVs.

1.

Select Windows Media.

2.

Click its Preset drop-down list (the next figure shows fewer than half of the NTSC presets).

MPEG encoding

MPEG (Moving Picture Experts Group) is a working committee of the ISO (International Standardization Organization) and the IEC (International Electrotechnical Commission).

MPEG is in charge of the development of standards for digital audio and video compression. Established in 1988, the group has produced several compression standards, including:

  • MPEG-1 The standard on which Video CDs and MP3 audio are based. MPEG-1 video is VHS-quality video with CD-quality audio at up to a combined data rate of 1.5 megabits per second. Its resolution is only 352x240 (about 25% of full DV quality).

  • MPEG-2 DVD and satellite digital video with a data rate for standard definition video from about 3 to 15 Mbits/second (7-9 Mbits/sec is the generally accepted range for high-quality DVD video) and 15-30 Mbits/sec for HD. MPEG-2 also supports multi-channel surround sound audio encoding.

  • MPEG-4 Multimedia for the fixed and mobile web.

    All MPEG standards use similar encoding techniques. They compress video by selecting keyframes or

    Intra-frames (I-frames), then removing a few of the frames between I-frames and replacing them with B-frames (backward frames) and P-frames (predicted frames). The B- and P-frames store only the differences between I-frames.

Standard DV can't match broadcast-quality or film

You probably shot your videos using standard DV, also known as DV25, so named because of its 25 Mbits/second video data rate. Combined with audio and error correction data, DV25's actual bitrate is 3.6 MBytes/second. Broadcast quality DV DV50 has twice that data rate due to extra color information. So when you view DVDs that started as DV25 videos, do not expect them to have the visual quality of broadcast or satellite TV or Hollywood feature films.

1.

Click the Export Settings > Format drop-down list and note that there are five MPEG file formats:

  • MPEG1 1.7 Mbits/second with MPEG-1 audio.

  • MPEG1-VCD (Video CD) 1.15 Mbits/sec with MPEG-1 audio. This file format is specifically to view about an hour of less-than-VHS-quality video on a CD that will play on most consumer DVD video players and computer DVD and CD drives. You'll need to use stand-alone CD-writing soft ware to create a VCD.

  • MPEG2 The presets are geared to high-definition and progressive scan videos. If your goal is to create standard DVD content, select MPEG2-DVD. If you want to tweak the MPEG-2 parameters, select MPEG-2.

  • MPEG2-DVD Offers the most presets. Select a preset that gives you the best quality while not exceeding the 4.7 GB of space on a DVD. To help you find the right fit, the Media Encoder has an Estimated File Size display that updates each time you change a preset or a customized setting. You'll take a look at that in a moment.

  • MPEG2-SVCD Super Video CD. Like a VCD, SVCDs can play on most consumer DVD players. They hold about 35 minutes of low bit rate (2 Mbit/sec) MPEG-2 video.

2.

Select MPEG1.

Look at the Estimated File Size display in the lower right corner of the Media Encoder. It should read about 7 MB.

Note

The sequence is 30 seconds long. If you were to export it as an AVI file (with its DV25 bitrate of 3.6 MB/sec) it would be about 110 MB16 times larger than the MPEG-1 file.

3.

Select MPEG1-VCD.

Depending on the Preset you select, the Estimated File Size will be about 25% less than MPEG-1.

4.

Select MPEG2.

5.

Click the Preset drop-down list and select NTSC MPEG-2 Generic.

Check its Estimated File Size and note it's more than twice the size of an MPEG-1 file but still much smaller than the AVI file.

6.

Click the Video tab.

7.

Click that panel's Fly-out Menu and select Expand Advanced Settings (if the option is to Collapse Advanced Settings, then do nothing).

Note

All the other Formats except Macromedia Flash Video have Advanced Properties. I chose to show you MPEG's because it has the most advanced properties.

8.

Scroll down that panel's view and take a look at the Bitrate (the GOPGroup of Picturesand Advanced Settings go beyond the scope of this book).

  • CBR (constant bitrate) This works well for Internet applications because the bitrate does not fluctuate.

  • VBR (variable bitrate) Generally gives you better picture quality than CBR at the same bitrate because it increases the bitrate during action scenes. It offers a one- or two-pass option. Two passes take longer but create a higher quality image. Use VBR when creating a video for a DVD.

9.

Click the Audio tab and change the Audio Format to Dolby Digital.

That gives you a wide range of options including Surround Sound (in the Audio Coding Mode drop-down list shown in the next figure).

Note

Windows Media has a 5.1 option but only for its HD file types.

10.

Click OK, give your file a name, click Save (or Cancel) and rendering (transcoding) will begin. Depending on the quality level settings and the speed of your PC, this can take about two times the duration of your project.