Tel: 905–690–4709 dk@tfwm.com - Darryl Kirkland, Publisher

Mastering Media Compression

Back in the late 1900’s (1980’s to be more precise) as video technology became available to the masses the ability to shoot, edit and “premiere” (display and/or distribute) “in-house” video productions captured the imagination of individuals and ministries alike. The answer to the question of what format the completed video/media needed to be to be produced was relatively straightforward (and definitely non-digital). For many ministries on very limited budgets that “final format” (production master) was VHS tape (which, as you know, stands for Very Horrible Signal) or perhaps higher-quality 3/4” tape.

Larger ministries may have had access to broadcast quality video mastering formats such as 1” or Beta (not the consumer Beta video format which lost the consumer video “format war” to VHS but the long-standing professional Beta format). Video compression was unheard of and unneeded. There were no DVD’s to burn or author. No video-on-CDRoms to master. No worship presentation software. Not a video projector in sight. And the letters “www” went unseen except on documents produced on typewriters with a sticky “w” key. Computers and video gear did not “talk” to each other let alone fit on the same desk top and the video iPod was merely a gleam in eye of Apple’s Steve Jobs. “Digital” was a word reserved for clocks, watches and calculators.

Fast forward 20+ years and the options for “distributing” that same video content, along with the corresponding technologies, have multiplied exponentially, web streaming, DVD mastering, interactive CDRom, vidcasts, worship presentation software, “small screen” technologies such as the just-mentioned video iPod (and its many competitors), Sony PSP, cell phones, PDA’s and dedicated portable media players. And, yes, videotape in its many digital (and analog) formats (miniDV, DVCam, BetaSP, Digital8, HDV, DVCPro, and an ever-expanding assortment of emerging HD formats).

HONEY I SHRUNK THE VIDEO
For the vast majority of us using video in ministry, a fairly recent addition to the video production equation is “compression”, also referred to as “encoding” (I will use these terms interchangeably within this article). Technically speaking video compression is being applied to today’s digital video formats (miniDV, DV, etc.) as it’s being recorded within the camcorder but we’ll be dealing with issues related to video compression after the footage has been recorded either with a camcorder or master recording deck. Once video is captured (digitized) into the computer for editing in the highest quality format provided by the hardware and editing software (usually .avi, .mov. or a proprietary format created by the hardware/software manufacturer) the goal is to maintain that high-quality as long as possible through the editing, mastering and distribution process. Video compression is often the final step in that process and is necessary in order to accommodate the limitations inherent in whatever technology will be displaying the video content. The type and degree of compression needed is determined by the intended method of display and/or distribution. For example, video intended for DVD authoring doesn’t need to be compressed nearly as much as video intended for download or streaming on a web site or playback on a portable media player. Full-motion 30 frames per second (fps) video takes up a lot of space. For example, a 5 minute video clip captured in the .avi file format results in approximately a 1 gig file. That’s 12 gigs per hour of video which is much too large to “pump” through even the fastest internet pipeline or state-of-the-art portable media player.

Enter video compression. Video compression is definitely an art unto itself with its own sometimes confusing technologies and pitfalls. Let’s take a look at some of the most common applications of using video in ministry requiring video compression along with some of the terms, technologies and techniques to help you along your journey towards encoding “bliss”.

Here’s a look at some common media ministry applications requiring video compression technologies and techniques. Your mileage may vary.

DVD
The current video compression format of choice for DVD authoring is MPEG-2 which is a “lossy” compression format which means you will lose a lot of picture quality if you apply a lot of compression. Standalone DVD recorders (computer-less) handle the MPEG2 encoding process seamlessly as they record the incoming audio and video directly to DVD and are definitely the easiest solution for hassle-free DVD mastering/recording and the resulting MPEG-2 compression. Higher end DVD recorders provide the opportunity to adjust some of the compression parameters (Kbps, etc.) but not to the degree of computer-based encoding solutions. When authoring DVD’s on computer the content will need to be encoded to MPEG-2 so look for a DVD authoring program which can also provide the encoding along with DVD design (buttons, menus, titles, etc.). The short story is you get what you pay for meaning the cheap or free encoding solutions are not as good/fast as the more expensive encoding programs. By the time you read this the first generation of HD (High Definition) DVD recorders are hitting the market although unfortunately another “format war” has emerged as Sony, Dell, and HP among others are touting Blue-Ray HD technology while Toshiba, NEC, Microsoft and others have circled their wagons around HD-DVD. Both formats promise greatly expanded capacities (15-25 gig per DVD and beyond) and improved picture quality.

PRESENTATION SOFTWARE
When shopping for a worship presentation software solution (MediaShout, EasyWorship, SundayPlus, etc.) one of the first things you’ll want to know is what video formats it “likes” the most (plays back with the greatest stability and ease). Check the software manufacturer’s web site to find out this information or contact their tech support directly if you want even more details. On the PC common video compression formats for use within presentation software include MPEG-1 (.mpg), Windows Media Video (.wmv), MPEG-2 (.mp2) or perhaps AVI (.avi). On the MAC platform Quicktime (.mov) is the preferred format. Microsoft’s Windows Media Encoder is an excellent (and FREE!) encoding solution for compressing your digital video files into the Windows Media Video (.wmv) format. You can download it directly from Microsoft’s web site. I prefer to use .wmv over MPEG-1 (.mpg) whenever possible for it’s superior picture quality and small file size. But consider yourself warned, video compression technologies and the resulting formats are changing (and changing fast) regardless of what platform (MAC or PC) you are using. New, much more efficient compression formats (codecs) are emerging such as MPEG-4 and H.264 which is the perfect segue to our next section.

THE NEXT SMALL THING-PORTABLE MEDIA DEVICES
Video iPods, PSP’s (Sony’s Play Station Portable), and portable media players are among today’s hottest media technologies. These little portable marvels of mobile media barely existed as a category 5 years ago. I’m still not convinced I want to watch movies, TV or any other video content for that matter on a 1.5” screen (or smaller!) but with iTunes, Google, Microsoft, Yahoo and others offering video-on-demand of popular programming at $1.99 a pop for instant downloading and viewing on these PMD’s the revolution is upon us regardless of this authors small screen viewing preferences. As the body of Christ we now have the opportunity to produce and provide “mobile ministry” by producing (and compressing) content with much greater (hopefully) redeeming value than “Lost” and “Desperate Housewives”. Whatever the nature of the content if you want to encode video for small screen viewing you’ll want to use the MPEG-4 or H.264 compression codecs/formats resulting in the file extensions .m4v, .mp4 and .mov. These new compression codes are extremely efficient and provide good picture quality in small file sizes ideal for viewing on portable media devices. For example, when preparing video for playback on Apples video iPod you’ll want to use a resolution of 176 x 144, a frame rate of 10-15 fps and a data rate of 50-60 Kbps. For $30 you can purchase Quicktime 7 Pro (www.apple.com) which is the most affordable and easiest encoding solution for accomplishing this. Check the owner’s manual of your specific device to find out what video formats it supports.

CDRom and Video CD (VCD)
Approx. 45 minutes of video can be packed on the standard 650 megabyte CDR compressed in the MPEG1 (.mpg) format. In comparison, if you’re creating a VCD (a CDR containing MPEG-2 video content playable on most stand alone set top DVD players) approximately 15 minutes of MPEG2-encoded video will fit on that same 650 megabyte CDR. Many video editing programs provide MPEG-1 and MPEG-2 encoding directly from the timeline for recording digital video to CDR and/or DVD such as Adobe’s Premiere Pro and Canopus’s Let’s Edit 2 or Edius Pro 3.

WEB STREAMING/DOWNLOADING
If you’d like to stream video to the masses via web you’ll need to decide between three primary streaming formats (architectures): Quicktime, Windows Media or Real Media. Although it’s way beyond the scope of this article to address all the variable pros, cons and specifications of each here are some basics to help you format your media to fit the medium of web delivery.

When selecting the compression bitrate remember the connection speed of the end user. High bit rates are usually better for users who have high-speed connections and low bitrates are better for users with low-speed connections such as dial-up modems. Since not everyone has access to a high-speed internet connection you’ll want to offer your web video for those with dial up connections as well as high-speed connections. The best way to increase or decrease the file size/quality is to a) adjust the fps to a maximum of 30 fps or a minimum of 10 fps; b) adjust the data rate (Kbps-the higher the rate the better the quality) or c) adjust the window size/resolution (320 x 240, 240 x 160, etc.). Typically you’ll want to use a window size of 320 x 240 or smaller for video destined for web streaming/downloading. The best compression software solutions provide easy-to-understand and easy-to-select compression settings based on the intended end use. (dial-up, high-speed connections, CDRom, DVD, email, etc.)

RESOURCES
So much more needs to be said about the unique art of audio/video compression but our word count is just about all used up. Thankfully there is a lifetime of great resources both on and off the web for making sure your media ministry is properly fitting its media for the intended medium. Take one digital step a time in your journey to spread the gospel through today’s many media outlets and avenues. No doubt, we’ll see even more opportunities and technologies in our lifetimes to tell the old, old story in some very new ways. Blessings to you each step of the way. I’ll sign off by passing on some of my favorite web sites for learning more about video compression and finding compression products/solutions. And remember, GOOGLE is your friend!

www.videoguys.com

ProCoder Express www.canopus.com)

Quicktime 7 Pro www.apple.com)

Videora Converter www.videora.com/en-us/Converter/

www.webmonkey.com

www.askjeeves.com

www.mpeg.org

www.wikipedia.org

www.mediacollege.com

www.moviecodec.com

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