| Post-Production |
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This phase involves everything after production including television system conversion, capture, editing, pre-processing, output, encoding, integrating metadata, interface design, creating the web pages where it will be published, and posting to streaming servers. This is where the fun begins... turning plain video into a quality interactive multimedia experience. No more worrying over pre-production oversights, no more sweating the production disasters. Now you get to be creative with graphic design and build a presentation that viewers will engage with and retain more, that is if you choose to embed your video in a Web page. Acquire footage or digital filesSome of you will be capturing your own raw footage to edit yourself. You can then proceed to the Capture section. Others will be getting footage or an edited master from a customer or Post house. A Post house will likely be able to capture to an MPEG file so it's definitely worth asking for one to negate conversion and capture. If you're outputting to tape or DVD, request MPEG-2 (full size). If not, MPEG-1 (half size) will do for streaming files. Set up an FTP space somewhere to transfer these big files at lightning speed. Your personal web host usually provides FTP service. Otherwise put it on a network drive and transfer it with Windows Explorer. If the Post house or production company doesn't digitize, request a miniDV copy of the footage so you can capture with your DV camera via Firewire. If that's not possible, request a master copy in whatever format they use and have a local conversion / duplication company convert it to your tape format or CD. Convert system formatIf production and / or editing is done overseas, the television system format of the tape (NTSC, PAL, SECAM) may need to be converted to your system. For example, if you're in the US, getting a PAL BetaSP tape shot in Europe FedEx'd and having a video conversion / duplication house locally do the conversion to NTSC miniDV works well. Do it yourself and you can get it down to 5 days instead of 2-3 weeks. Asking the Post house to convert it to NTSC and transfer it to miniDV can take awhile as they'll probably have to send it out. Therefore, it's much faster if you can get the Post house to capture the files to MPEG-2 and post them to your FTP server, taking as little as an hour instead of 5 to possibly 21 days. Here's a list of countries and the television systems they use. TIP: I have used FedEx International Priority 2-day to get BetaSP tapes from Europe. I'll have a FedEx package to my local conversion house ready to send out the day the tapes arrive including a prepaid return package for return delivery back to my studio.Capture
Acquire adequate workstation and peripherals
You'll need to acquire an adequate workstation (and peripherals) with enough RAM and disk space to handle video capture and editing (see suggested workstation components below). A video-capture card is necessary to capture audio and video if Firewire isn't built-in. It's better to configure the workstation with Firewire to begin with. Otherwise, there are basically two types of capture cards: capture from an analog tape deck or camera, and capture from digital video decks or camcorders using FireWire (sometimes referred to as I-Link or Lynx). This interface is capable of data transfer rates up to 400 Mbps so it's perfect for handling the amount of data needed to transfer real-time video. Both analogue and digital cards capture video in real-time. However, an analog capture card will either degrade the capture via compression or will create raw .AVI files with enormous file sizes. Firewire is definitely the way to go, and comes built-in to most PCs now—certainly multimedia workstations—and negates a capture card altogether. Dropped frames during capture are something you want to avoid. Removing dropped frames is tricky and can make a voiceover stutter if you edit out those frames. Optimize and test your system until you reach zero-dropped frames. They're usually a result of a configuration problem, trying to capture video that exceeds the capture rate for your system, or more likely a fragmented hard drive. Backup (then delete previous projects) and defrag your drive often. You stand a better chance at zero-dropped frames if you have contiguous disk space to write to. TIP: Don't bother with USB 2.0. Firewire is the standard transfer protocol in the DV realm. Stick to Firewire peripherals such as the external hard drive and the DVD+RW drive. TIP: Canopus breakout box is a great alternative to an analog capture card, and has an added bonus. The breakout box has Firewire in / out, analog audio and video in / out, and S-video in / out. You will probably get a VHS tape at some point to capture, maybe even a cassette tape. This box allows you to input analog sources yet output Firewire for capture. The bonus is, in your Premiere project file you can preview video on a TV monitor at full frame rate without hardware acceleration! Perfect for checking video levels going out to tape. Editing
Editing activities include arranging various sections of captured clips into a timeline, inserting transitions, incorporating graphics or visual effects, applying pre-processing effects, mixing and synchronizing audio, and possibly adding titles. Bear in mind the limitations of the Web and avoid unnecessary motion that will make streams 'smudgy', namely fancy transitions... stick to cuts and quick fades. Note: Professional video editing is a learned skill through experience, and can't be encompassed in bullet points. These are just highlights as it pertains to streaming. The main thing to emphasize here is to create properly timed transitions. Preview edits carefully before committing to them. Watch for 'stuck' frames and make sure it's a smooth transition. Consider outputting edits to a short clip to verify them before proceeding versus relying on RAM previews. Adjusting edits later is time-consuming.Pre-processingPre-processing improves the quality and levels of source files. This is where you'll fix marginal audio and video. Look at the quality improvement in the adjacent clip. Hopefully the production crew did a good job with audio quality and video levels. Many times however, audio levels are too low and video contrast needs adjusted for PC delivery. Pre-processing prior to encoding also reduces the burden on the compressor, i.e., increasing black levels to eliminate grain. Adjusting Color and Brightness
Video levels for tape / WebVideo is much darker on a PC than it is on tape / TV. And video on a Mac is brighter than on a PC. So, if you're outputting to tape as well as a stream, you'll want to pre-process them separately (create separate Premiere projects). Keep your MPEG-2 for tape unadjusted brightness-wise even though it looks dark. This is why it's a good idea to have a cheap TV monitor included in your system to check video going out to tape / TV. On your transfer file for streaming however, go ahead and brighten it up to where it looks acceptable on your monitor, but be sure to calibrate your monitor first. Audio Pre-ProcessingIt's very helpful, most times necessary, to export your audio track(s) from your video editing software to a .WAV file and open it in a dedicated waveform editor (audio application) such as SoundForge. This allows you to see the waveform up close and determine levels quickly. Always check audio levels of your source footage and not just turn your speakers up (or down).
OutputDuring pre-production (Output Requirements), hopefully you ascertained what output formats you'll be targeting. Output your edited video to:
For the .AVI streaming file, output to the highest size you'll be encoding to, be it 320x240 or 240x180. Use the MPEG-4 v2 codec with maximum settings (the least amount of compression) so file sizes are manageable. Uncompressed isn't necessary and the file sizes would be huge, even for just a 10-min. video. Settings for the audio output should be 16-bit stereo at 48k. Tip: At encoding, specify mono audio in profiles to conserve bandwidth. But keep this output file stereo for tape, DVD, or CD. Getting the Proper Image Parameters
Calibrating your monitorBear in mind that no matter how good you get your video looking on your monitor, your viewers will be running different platforms, different monitors with different graphics cards with different brightness / contrast settings at different resolutions... it's a stab in the dark. Test your output on several co-worker's systems to get a consensus of how it looks on other machines. Then calibrate your monitor to those test results and keep it that way. Once you're roughly calibrated, don't adjust your monitor because a DVD or video you're watching happens to be dark (or bright). You'll have to recalibrate. It's the same principle as calibrating for accurate print colors. Test, calibrate, and leave it.Notating marker timecodesBefore you close your editing software and get to encoding, notate the timecodes where you'll want to place markers for chapterization (jumping to different parts of the video) if you choose to implement them. You may have separate clips you've laid into your timeline and can simply zoom in to get those in / out points. Or, you may have a single hour-long clip where you'll need to log the video by watching the whole program and writing down the spots where you want to put markers. Write these timecode markers directly into this Advanced Script Indexer (ASI) text file for importing later. Save this file as "markers_scripts.txt" to your hard drive and don't change the formatting so ASI will import it correctly later. Keep a copy of this file for entering your markers in future projects. It's much easier than entering markers and scripts through ASI. TranscribeOnce the edit is signed off and approved, it's a good idea to have someone transcribe the video to allow downloading from the site. It will also provide the text for the SAMI file used for closed captioning, as well as aid in adding markers and scripts. Translations to different languages should be transcribed and proofed if language use will be enabled in closed captioning.
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| Last Updated on Tuesday, 21 October 2008 13:30 |




