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AVCHD Format Discussion
Inexpensive High Definition H.264 encoding to DVD, Hard Disc or SD Card.

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Old January 1st, 2010, 05:50 AM   #16
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Next time we get a good snowfall here, I got to suck it up, bundle up, get my buns out the door and shoot some 60p of my puppy bounding along through the snow drifts. (Dang it's cold out there though!) It's made for video kinda stuff. She's absolutely hilarious in fresh snow that's deeper than she is tall.
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Old January 1st, 2010, 06:00 AM   #17
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I just rendered and upped a sample from the HF10 50i converted to 50p and slowed down and in 720p. Nice and smooth now. Switch HD on the clip is only 23secs.

Don't get me going on dogs Robert, i love mine and love videoing them even more.

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Old January 2nd, 2010, 01:31 PM   #18
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What I noticed in the earlier clips was that signature chop that you get when shooting at 24,25,30p - sort of looks like objects are "jumping" from one spot to the next when moving - I get this with video from my HX1 (30p). While in theory our eyes shouldn't detect the separate "frames", perhaps as we've become used to higher quality and frame display rates, these "glitches" become more noticeable. I don't think it detracts from the footage (good content is good content after all!), but for someone who shoots video, these "little things" become more apparent, and sometimes annoying - the average viewer would never notice....
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Old January 2nd, 2010, 01:56 PM   #19
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The way the brain perceives motion, 24p is really pushing it for high motion sequences. To get genuinely fluid motion (perceptually), you really do need to get up in the neighborhood of 50-60fps. That's why I generally like shooting 720p60 better than 1080 line video. You really don't lose a whole heck of a lot of spatial detail (perceptually) when displayed typically (on a television in your living room, as you relax in your easy chair), but you get noticeably more temporal resolution, especially in high motion sequences. That's especially true with footage from (consumer or) prosumer cams that tend to resolve no more than 600-800 lines of detail anyway, and even more so with HDV, where the compression is on the hairy edge of recording HD material reasonably faithfully. That's not a knock on HDV - simply acknowledging the realistic limits of 24Mbps MPEG-2 compression. When the HDV standard was developed, it was actually a very brilliant, elegant solution, for creating a system that works reasonably well for recording HD material, yet re-used a whole lot of off-the-shelf technology, allowing it to be pretty affordable (not incurring a ton of R&D costs, and pushing the edge of the envelope hard from a technological perspective, which always costs an arm and a leg and often produces unreliable results). AVCHD is a notable improvement, quality wise, for affordable recording of HD material, compared to HDV, but was simply not practical at the time (for several reasons).
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Old January 2nd, 2010, 02:34 PM   #20
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One of the reasons I posted that video I shot of my puppy, earlier in this thread, is it's actually a very good example of 24p at 1/48 shutter working well to (reasonably) faithfully acquire the images for real-time playback. The other reason I posted it, is I just plain enjoy watching it (even after viewing it countless times before - love that little pup!).

Not that I can't use more practice, but it's entirely hand-held footage shot reasonably well. It's reasonably steady (image stabilization certainly helped) where the subject (my puppy) is pretty stationary (rare!) and tracks her fairly well when she's hopping and zipping around.

In Ian's first footage posted in this thread, cranking the shutter to 1/250 was necessary under the circumstances (which blew right by me at first, the other night, when I was sleep deprived!) to get nicely viewable footage.

Generally speaking, at 24fps, 1/48 shutter works best (and 1/50 for 25fps). Obviously, as with Ian's footage, that's not always the case (general rules were made to be broken when circumstances call for it). Ian clearly knows what he's doing with a camera, and how to get the best footage out of the camera he was using, under the circumstances he was shooting in (flying along on a Jetski - hardly a stable platform to shoot from!).

Shooting at 24p 1/48 shutter, the camera op needs to be quite careful with camera movement, or the footage will invariably look choppy, stuttery, strobing, or whatever you want to call it. Essentially, that boils down to either very slow camera movement (and without camera shake) when the subject of the footage is relatively stationary, or following the subject's movement pretty accurately (again, without shake) when the subject is moving fast.

It takes knowledge and practice to develop the skill for shooting low fps footage well. I'm still learning (always will be).
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Old January 2nd, 2010, 06:03 PM   #21
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The other reason i now shoot 1/250 50i in good light with the Hf10 is for some reason, rolling shutter or jello issues are not as apparent. I can't explain this as shutter speed should have no effect on CMOS jello, i believe frame rate does. Another explanation for the lack of jello could be that the exchange of info from the sensor to the processor may be optimal when in good light and high shutter speed. All i know is from trial and error 1/250 seems to be the sweet spot.

I have tried shooting 25p from the Hf10, definitely not suitable for high motion.

The other area of improvement is the stability of the camera and housing, it is dynamically balanced similar to a steady Cam system with added weights in appropriate places. I can only just hold the rig for 5 mins at a time before i need a 1 min rest. Both hands are on the rig so only have my knees to grip the jet ski seat, but i think this works to my advantage further isolating bumps and jerks from the jet ski.

Dave i agree most people on this forum are shooting or watching filmic type videos shot in 24p so that smooth movement has become the norm.

Cheers Ian (Rambo)
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Old January 2nd, 2010, 06:30 PM   #22
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Personally, I've just never shot any video where "jello effect" from CMOS seemed to be any sort of a problem (at least not that I've ever actually noticed). The puppy video I posted in this thread, is from an HV20 (CMOS), with some pretty dang fast camera movement in a few spots, yet I don't see any "jello effect" that's noticeable at all.
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Old January 2nd, 2010, 07:47 PM   #23
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Yes Robert, not much noticeable jello in there at all, i think the motion blur masks what little there is and also obviously your experience with the camera. Ain't it nice to have fun pets.

Cheers Rambo
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Old January 2nd, 2010, 11:58 PM   #24
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Quote:
Originally Posted by Ian Newland View Post
Yes Robert, not much noticeable jello in there at all, i think the motion blur masks what little there is and also obviously your experience with the camera. Ain't it nice to have fun pets.

Cheers Rambo
Yeah, I sure love my puppy. Jewel is indeed a genuine best friend. We had a "family" dog for awhile, when my kids were growing up, and I've been "an uncle" to several wonderful dogs over the years (a couple of girlfriend's dogs and a one time room-mate's dogs years ago), but she's the first dog that's been all mine (and I've had her almost since birth - was there when she was born, and I took care of the pups almost entirely from about 3 weeks of age until they were ready to find permanent homes, because my friend who owns the mother of the pups could not keep them in her apartment - management was not thrilled - so in a pretty real sense, I guess that makes me a genuine daddy of sorts, to Jewel and the rest of the litter, by adoption). Jewel got her name because she had a tiny diamond-like marking right smack dab in the middle of her forehead at birth. That's gone now (disappeared pretty quick as she grew - and good lord did she grow! - might be the world's biggest Corgi now, at well over 30lbs!), but the name stuck. Jewel can certainly be a first class mischief maker, but she's always good natured, and just loves her "daddy" for sure.

Actually, I don't really have what I would consider all that much experience, shooting "real" footage, but I do appreciate the compliment.

I'm disabled (have been for many years - almost 15 now), and living on an incredibly limited income. If not for the good fortune of having a brother and a son who've done reasonably well for themselves, and a mother who's just plain quite generous by nature, I simply would not have access to some reasonably nice video cameras and computer equipment.

Largely to save money, but also because my health keeps me at home often, rather than spend a pile of cash I don't have, on video tapes to experiment shooting with, I've shot a whale of a lot of test footage over the years, using cameras tethered to my computer in my "office" (spare bedroom), recording directly to disk. I like to think I've learned quite a bit, by doing that. For example, I've practiced holding cameras steady, simply by zooming to the max, and trying my best to shoot stable hand-held footage (of anything that happens to be handy to aim at in the room at the time). I still can't shoot an image of well used coffee cup 6 feet away, zoomed at 10x, without it looking a bit like we are having an earthquake in Minnesota of all places (coffee never seems to spill tho!), but it is great practice.

When I shot the footage I used in that video I posted earlier in the thread, I was actually trying to work out methodology for how to set exposure quickly with the HV20 (in a "real" and tough setting). It struck me as a dang good situation to make for a serious challenge. Most of my son's back yard is quite well shaded by trees, but it was a very sunny day (don't think there was a cloud in the sky that day) and portions of the back yard were very brightly illuminated by sunlight (heavy duty contrast to deal with). What I did that seemed to work pretty well, but was ultra fast, was to aim the camera at a portion of the yard that was mostly shaded but partially fully lit up by the sun (on auto exposure, but locked at 1/48 shutter), and fully lock down exposure after the camera had a moment to adjust. As you can see from the footage, I got mostly pretty good exposure that way. While my primary objective was to work out reliable methodology for quickly setting exposure outdoors with the cam, I did wind up with some nice footage that I'll treasure the rest of my life. Jewel was obviously having a great time with her much larger buddies (my son's dogs), and I truly enjoy viewing that footage, even after seeing it way more times than I can count (at least with my fingers and toes!). Jewel actually sometimes watches that footage herself, and pays close attention to it too!

I think I've also probably become something akin to a world class expert on video compression, from loads of experimenting in my "office" spare bedroom, particularly from a practical standpoint (achieving high quality results efficiently, both in terms of cost and encoding speed), and especially with some excellent, but freely available codecs, like x264, which is indeed one of the best implementations of an H264 codec available anywhere, at any price. I can also achieve excellent results with a very low cost MPEG-2 encoder (easily quite suitable for small scale DVD distribution, like for weddings and events, for example).

I'm hoping to find decent work someday, that I can do mostly from home (and at least earn a decent income again someday). Right now, I know I can do far better video compression for web video, with x264, than way more than half of what I see out there on the internet, even on websites you would think would have just top-notch video (like the closest ABC television network affiliate's website)! If you, or anyone else, have any need for first-class video compression (including pre-compression filtering, to optimize for encoding - especially useful for achieving the best results with highly compressed web video), I'm available! (for either doing compression work entirely, or for consulting on how to do it, either generally or for any specific purpose, like getting first class results with a Flash player, including how to host it for next to nothing) I'm working out methodology for bandwidth detection, which is essential for using multiple encodings (at different bitrates) for delivering optimum quality web video in real-time, as well as super-efficient methodology (from both a speed and cost standpoint, with excellent quality of course) for doing the multiple encodings (no small feat, but I think I'm more than half the way there)

I know this is starting to sound a bit like an advertisement, and I suppose in a sense it actually is turning into one (hopefully Chris will excuse that). Perhaps I should expand on this a little more (or maybe a lot more), but put it in the "Helping Hands" section instead. I really could use the work.
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Old January 3rd, 2010, 12:21 AM   #25
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Anyway, yeah it really is nice to have fun pets. Jewel is truly a godsend, for an "old" man (really just a spring-chicken at 52), who spends the vast majority of his time at home alone.
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Old January 3rd, 2010, 12:22 AM   #26
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Robert we seem to have "jacked" this thread but hopefully offered up some good experiences and helped someone.

You might be interested in this mans work with Flash Optimization for the web, some of his HD streaming encodes at small bit rates are unbelievable.
Flash Video Technology - Blog Ing. Fabio Sonnati 2009

Cheers Rambo
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