Clipmaking

[KillingFrenzy]

There's alot of talk about codecs and clipmaking.
I find that the 320x240 clips I'm making now look quite good. They look 100% better than when I started, and it really has a lot to do with tweaking your capture before you compress it.

Here are my steps to a good clip.

1) Resize the video to kill any black borders. VHS tapes especially will have generation loss and lines dropped at the bottom of the signal. Mirroring and tiling look better if you scale your image to fit the entire frame.

2) Color correct and optimize the image for brightness and contrast. Learn to use a waveform and vector scope within your editing app. Don't trust your screen, use the scopes to set your blacks to 0 (digital) and white to 100%. Make sure you don't clip the top end by applying too much contrast. I tend to boost the saturation a bit, since I want my clips to be vivid.

3) If you don't like part of a clip, kill it. Don't be afraid to chop something down to just the good bits. Chances are if you don't like something, you'll just be more and more annoyed you left it there in the first place.

4) Sharpen. In Premiere, I usually apply a standard Sharpen filter of "10." I'm sure there's and equivalent in most editing programs. You can actually go up to "20" on black and white clips, whereas higher values with color seem to accentuate tearing/chroma noise. You actually want your image to be uncomfortably sharp on your monitor. I would never create a DV tape or DVD with the sharpness at these values, but having your clips overly sharp seems to pan out by the time they get dumbed down by scan conversion, and then projected onto the screen. My overly sharp clips look just right as a projected image.

5) I use either Indeo XP codec at 80% with a keyframe of 2 for AVI clips. And I use PJPEG at 80% for MOV clips. The PJPEG files actually look about the same as the Indeo ones, but are larger. Unfortunately, Indeo isn't supported by OSX, so I'm moving to PJPEG just because I want my clips to be cross-platform.

6) For the love of mike, don't use MPEG4 based codecs. I was playing with my Jitter patch one day and suddenly noticed the framerate had dropped from like 50FPS to somewhere around 20. I assumed I must have done something awful to it. After fooling around for a long time to try and figure out how I'd messed up, I remembered that the clip I was testing with was MPEG4/Divx based. That's just an example of how big a performance hit MPEG4 can give you. Sure the file size is small, the quality good... but the decompression overhead is huge, and any sort of scratching style behaviour is going to blow chunks (chunks of decompression artifacts, actually).

So there's my little advice on good clipmaking. By following these methods, I'm pretty confident that my 320x240 clips look as good as a lot of peoples "rip it and compress without thinking" 640x480 clips. Obviously, the bigger the res, the better the image. The bigger the projection, the more obvious the resolution issues. Applying the techniques above to higher resolutions will look great, though the temporal performance quality will determine what resolution you can really effectively run at.

My final piece of advice, is to calibrate your computer output. Don't trust default settings. If possible, try and check your output on a waveform monitor. Compare your output to bars on your other sources. Try and get all your base output black levels to be the same, and then try and match 100% white as well. Fooling with the gamma curve often helps kill the grainy part of the lowend of video, giving you a nice contrasted image with less messiness in the blacks. The idea is to get your sources to match each other, then use your projector to make the whole thing look just right in whatever environment you end up in. Crank up the brightness and contrast on the projector if you have to, but your clips and computer output should be defined by standards that never change.

[robotfunk]

Originally posted by KillingFrenzy
By following these methods, I'm pretty confident that my 320x240 clips look as good as a lot of peoples "rip it and compress without thinking" 640x480 clips.

Word. Compression artifacts are usually much more severe than upscaled results from properly authored 320x240, at least that;s what I find.

I recognize something in most of your tips but I've never dared to touch 'sharpen' since it seems to accentuate problems on my (visually non reliable) TFT monitor. Gotta do some tests to see if it works as well for me.

additional tips from me:

-If not absolutely necessary, leave the video as much as possible in its original format. In europe, your DVD player will happily play NTSC DVDs, so if you end up with some NTSC footage, 9 times out of 10 it will look much nicer if you keep it NTSC rather than convert to PAL>

-Don't interlace unless you must. I've been authoring all my DVDs in progressive, and they play back fine on non progressive gear, but give the extra edge when its supported.

-Downscaling to the desired resolution shall be the last thing you do to the clip. Every operation you apply to a signal introduces some kind of error, eliminate by using higher def in the production process. Often, even upscaling (bilinear or bicubic) and then applying fx and then downscaling again looks better than without the up/downscaling. (This is why rotating a JPG in Flash or After FX look so much better than rotating an image in a Korg Entrancer)

-Applying a lossy codec should be only done at the last ever stage, see previous point.

Re color correcting: I think 100% black is illegal for NTSC broadcast spec.

[simot]

Originally posted by KillingFrenzy
2) Color correct and optimize the image for brightness and contrast. Learn to use a waveform and vector scope within your editing app. Don't trust your screen, use the scopes to set your blacks to 0 (digital) and white to 100%. Make sure you don't clip the top end by applying too much contrast. I tend to boost the saturation a bit, since I want my clips to be vivid.

good thread, some good advice. i found out the importance of the above the slow hard way.... if you get this sutff right your visuals have a much stronger impact. especially important this if you are working with footage you shot yourself on consumer level gear.

re codecs and resolution. i produce all my content @ 640 x 480 uncompressed, and then because i use a pc and a mac out gigging i batch convert to 384 x 288 MJPEG AVI (for elektronika on PC) and 640 x 580 PJPEG MOV (for Grid Pro on Mac).

now just waiting for the new powerbooks so i can leave the shuttle at home.......

[Kyle]

Excellent thread KF...thanks I made it a sticky in hopes of catching more attention and having other members add the trials and tribunes of clipmaking.

Question: What advice do you give to new users for preventing tearing and artifacts?

[simot]

Originally posted by simot
good thread, some good advice. i found out the importance of the above the slow hard way.... if you get this sutff right your visuals have a much stronger impact. especially important this if you are working with footage you shot yourself on consumer level gear.

re codecs and resolution. i produce all my content @ 640 x 480 uncompressed, and then because i use a pc and a mac out gigging i batch convert to 384 x 288 MJPEG AVI (for elektronika on PC) and 640 x 580 PJPEG MOV (for Grid Pro on Mac).

now just waiting for the new powerbooks so i can leave the shuttle at home.......

that should be "640 x 480 PJPEG MOV"

[Hambone]

If you haven't done so, try out the H.264 codec. It produces small files at high quality. I render all of my clips with H.264 at 1024 x 768 (projector's native resolution) to keep things sharp. Sending the image via DVI with no projector keystoning helps to keep it crisp, too. You can batch process your files in Generator, which I got free with Motion 2.

By using the Core Image and Arkaos VJ hardware effects and a 10,000 RPM drive, I can stream layers of the files at high frame rates without bogging down the computer's processors.

[Hambone]

Edit: That's Compressor, not Generator ^^^^^^

[makemassair]

compressor is damn fine software, as is motion and the whole FCP suite.

[kyote]

any performance hits to using sorenson? Or Apple's compressor.....dumb question for some but i keep getting different responses and would like to know if anyone has any info on the issue.. peace!

[redi]

H.264 is a great compression if you intend to only play video 'forward' -but it falls over (completely!) as soon as you do any kind of motion fx on it -don't even think of playing it backwards. -any solutions offered there?