Encoding to RealVideo

OK, now we have an uncompressed digital video file stored as AVI or Quicktime. It's encoded at 15frames per second, its size is 320x240 and colors are set to 24 bit. The file is probably huge, depending on the length it is probably 10 MB or greater. When this source file is encoded to RealVideo it will drop in size to less than one tenth its current size. It will compress even more if there is very little movement or if the speaker is a talking head.

I will be doing the encoding in RealProducer. Most development shops use one of Real's products for encoding. The low end of these, RealProducer, is free from Real. This program contains everything a low volume environment needs to produce RealVideo.

• It allows you to do live broadcasts, provided you have access to a Real Server. You'll need a fairly high-end machine to do the local encoding in near real time.
• Creates scaleable SureStream files for various modem speeds. The program encodes at various bit rates for different modems and then adjusts to the user's modem speed and bandwidth. Only two bandwidths can be encoded at once.
• Creates backwards compatible files for RealPlayer 5.0 users
• Control of data rates and Codec selections
• Creates audio and video content that can be streamed serverless from a personal page
• Creates pages with embedded content instead of using the G2 Player window

With all these features in the low end RealProducer you might wonder why you would need to upgrade to RealProducer Plus or RealProducer Pro. These two packages do have some other features that make them worthwhile. They include:

• Batch conversion - The most important feature for large volume production environments. In Real Producer Pro there are more features added which help in SMIL production and creating template driven sites.
  
• Drag and Drop batch processing
• SMIL Template integration
• Timeline interface for creating time-based presentations

I'll be discussing the base line RealProducer that can be downloaded here for free. Once RealProducer is installed you're ready to start encoding. When you first launch RealProducer you will have a choice of file types to encode. You can encode from a file, you can encode from a stream coming in from the video-encoding card or you can encode a live stream.

RealProducer

Let's start by encoding a file. Once you select "Record From File" Producer will ask you to pick the file. Not all video file formats are supported. Quicktime is only supported in uncompressed format. This is why it is always best to work with an uncompressed file.

• Audio (.au)
• Waveform audio (.wav)
• Video for Windows (.avi)
• QuickTime for Windows (.mov); requires DirectX 6.0

Once you choose the file you can add name, author and copyright info to the file. Your next choice is to encode it for a single stream rate or to encode to SureStream format which is only supported on the new G2 Servers. We'll get back to the SureStream format later, so for now let's encode a single stream. The next step is choosing the bandwidth for playback. This means understanding your target audience. If you're encoding for average Internet users there is a big trade off between 28.8 video which is virtually unviewable and 56K video which is more watchable, but results in lots of buffering time for end users. For high action video I would always choose 56K; you might get away with 28.8 video for a talking head presentation.

Once this decision has been made, RealProducer asks you what type of audio you are working with. Is it voice, music or a mix of the two? Similar questions are asked about the type of video. Is it mixed video with some high movement pieces and some still shots, in which case Normal Motion video should be selected? Is it mostly talking heads, in which case Smoothest Motion should be selected? Or does it have lots of motion, in which case Sharpest Image Video should be selected? The final selection, Slide Show, produces a number of very clear sharp pictures from the video, however they don't really appear as video. This option is good for a video slide show.

Finally, you name your video file and save it with an RM file extension. Once all the selections are made check the final configuration, return to the main interface and hit Start. The speed of encoding is determined by the speed of your computer.

Shooting the Video
RealVideo - Waiting on Broadband
SureStreaming