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[jgreen]

So I go cruising over to YouTube's Olympics site (Youtube-slash-olympic), and it looks like things are progressing quite well there.  However when I downloaded an HD clip from the Salt Lake Olympics, I'm left with more questions than answers.  So I turn to the Forum!

I picked the biggest HD I can find there, and it comes down as 1440X1080, an odd aspect ratio.  Hmmmmm.  A quick bit of arithmetic tells me this resolution is exactly twice the size of good old 720X540.  Is it possible this "quote HD" wasn't necessarily--as Lady G says--born this way?

I ask because why in the world would I donate my bandwidth to downloading uprezzed clips, when I can do a better job on the fly with JRiver? And how can I tell ahead of time when all they give is the pixel height?  I ask you!! 

Don't forget that these doubled uprezzes are FOUR TIMES the data, and that is a stinkin waste of free downloading.   

[glynor]

I just read the subject line and I thought...

Oh, man, Mr. Tab... I hope you have a while.  Here, have a seat.

[Scolex]

1440 x 1080 is just non widescreen HD (1.33:1), there are many cameras that can record at that resolution.

[glynor]

1440 x 1080 is just non widescreen HD (1.33:1), there are many cameras that can record at that resolution.

1440 x 1080 isn't non-widescreen.

This is a standard 16x9 display aspect ratio resolution used by all sorts of professional digital video cameras from DVCProHD, to HDV, to Sony XDCam.  It is probably the most commonly used "1080p" sequence preset used out there until just recently (and it is still very common on pro gear). In fact, my two Panasonic P2 cameras shoot in exactly that format when in "1080" mode.

Pixels aren't always square.  Pixel aspect ratio does not equal display aspect ratio.

[glynor]

If you really want to make your head explode, learn about chroma sub-sampling.

Video doesn't work like computer monitors.  It doesn't even use the same kind of color space.  Most video is recorded and produced in YCbCr color space (as opposed to RGB or CMYK for computer monitors or pre-press work).  YCbCr is like Lab Color if you've ever played with it in Photoshop.  It is made up of three channels, just like RGB.  Only the Y (Luma) channel is a grayscale image that looks like a photograph.  And the two Chroma channels (CbCR) are "color maps" that are layered on top of this grayscale image.

Each frame of video isn't even all the same resolution depending on what "channel" you are looking at.  Generally the "resolution" they give you is the Luma channel's resolution (1440x1080).  The two color channels (chroma a & b) are almost always 1/2 to 1/4 of the size (and they pull tricks with the filtering pattern used to make it compress even further).  The human eye is more sensitive to "lightness" (shades of gray) variation than it is to color variation, so they use this fact to save space when recording and broadcasting high-data-rate video content.

Standard broadcast 1080p is usually 4:2:2.  This means that each luma channel (the black and white image that defines "what" you see) is 1920x1080.  However, the two chroma (color) channels are actually only 960x540.  That saves space, as opposed to sending a full RGB style so-many-bits-per-pixel image across the ether.  What you get off of your Digital Cable box is quite likely to be 4:2:0 (if you're lucky), or 4:1:1 (if you're not), then further recompressed (too much) with poorly applied automated H.264 compression on the back-end.  Tape of a tape of a tape of a tape of a tape.

Modern high-end cinema cameras often shoot in 4-5k 4:4:4 format (no subsampling), like the RED Epic we use here at work.  But those data rates are IMMENSE.  The RED footage I have on my array runs 3.5-5GB (that's gigabytes, not gigabits) per minute of footage, and if you enable HDR mode, it doubles in size.  And even that is compressed-to-all-hell.

That's why I always laugh when people on the forums say "I want to convert my video file uncompressed and blah blah blah".... And I (and people who know) think "No, you don't, because your hard drive won't be fast enough to play it, unless you have an array of SSDs in there, and then you won't have enough money for tomorrow's lunch."

[jgreen]

Staying in two dimensions (no pbd), 1440X1080 seems to be HDV, which I guesss was used a lot a few years back for sports shoots, for example the Salt Lake Olympics whose clips I was viewing.  I had thought this was all 1280x720.

However, my question remains:  For those of you who have UPloaded to YT, aren't there actually tools to convert your 320x240-kitten-playing-with-a-string video into 1920x1080?  I thought I remember reading about this, along with that preposterous rumor that man has walked on the moon.

[glynor]

aren't there actually tools to convert your 320x240-kitten-playing-with-a-string video into 1920x1080?

Well... Yes and no.

You can convert and upscale anything if you want.  Going from 320x240 to 1080p is going to look like doodie, but sure you can scale it.

In Final Cut, you just make a new 1080p sequence and drop the source footage in and it automatically scales it up.  It has to render it, and it doesn't use the smartest scaling system in the world, but it does a decent job.  I'm sure most other video editing applications have something similar/identical.  A smarter way is to run the source video through Compressor (or Telestream Episode if you have it) and upscale there first, as they have higher quality scaling algorithms built in (though they're slower).  Likewise, you could do the same in After Effects or Apple Motion if you choose (Motion has a really nice automatic stabilization system too).  If you care, there are tutorials for this on the Creative Cow forums.  Here's one such discussion about going from 4x3 480p footage up to 16x9 1080p.

There are also hardware scalers built into many pro I/O systems, like the AJA Kona or the Blackmagic Design DeckLink.  Lastly, there are a TON of third-party software plugins that specialize on cleaning and upscaling.

But going from a 320x240, probably web (aka junk) compressed, source video to 1080p is laughable.  Is there some quick and easy consumer tool to do it?  I don't know... You can do it using MPEG Streamclip (which is free and actually has an awesome quality scaler).

Staying in two dimensions (no pbd), 1440X1080 seems to be HDV, which I guesss was used a lot a few years back for sports shoots, for example the Salt Lake Olympics whose clips I was viewing.

Like I said, that resolution is very common, certainly including Canon's implementation of HDV.  I would be very surprised if they used HDV for the Olympics (at least not for high-profile events) because it was a decidedly "pro-sumer" codec, but whatever.

To be clear, HDV is a codec.  Just like H.264 or XviD or Apple ProRes or AAC.  It doesn't particularly care about the resolution, though HDV was typically stored in 1440x1080 because that resolution would "fit" on a standard MiniDV cassette.  That's what it was designed for.  Shooting 1080p on MiniDV cassettes originally designed to store crappy quality standard def DV content.  HDV is a 4:2:0 codec, and so has even less color information than broadcast.  I'm sure it was probably used heavily in some spaces (the cameras were "cheap" and lightweight), but DVCProHD was certainly much, much more popular professionally a few years back in the same "era" (DVCProHD is a 4:2:2 codec and records at a MUCH higher bitrate with much less noticeable compression artifacting).  DVCProHD also uses the 1440x1080 resolution for "1080p mode".

Is it possible this "quote HD" wasn't necessarily--as Lady G says--born this way?

If they're (the content creators) really choosing to distribute it at 1440x1080 and they're professionals (one would hope), I'd guess it is being shot on DVCProHD gear at that resolution natively.  They might also be using AVCIntra (or one of the other H264 based variants) which sometimes uses that frame size.  In any case, it was almost certainly shot at 1440x1080 if they're distributing it via that format.  The same cannot be said for something that is "real" 720p (1280x720) or "real" 1080p (1920x1080), because people do up/downscale to those resolutions, as they're standard broadcast sizes.  But there'd be no reason to distribute at 1440x1080 unless you shot it that way.

But, much more likely, the frame size was "picked" by YouTube and they use 1440x1080 for ALL "1080p" content.  I don't know enough about YouTube's compression magic they do to comment for sure.  I know their quality is absolutely HORRID, and that their data rates for "1080" are so low that it is a joke that they distribute things in that format at all, but it wouldn't surprise me to learn that all 1080p content there uses that 1.333 PAR.  When you upload a video to YouTube, they compress it to their own delivery format, regardless of what source you give them.  YouTube does not upscale content.  So, if you only give them a 480p source, then your video's max resolution for playback will be 480p.  But they do downscale, so you'll also get a 360p version (or whatever smallest size they use).  If you upload a 1080p source (or higher), they create a 1080p "version" of their own (H.264 compressed and conforming to their standards).  All video uploaded to YouTube is recompressed on their servers.  There are no "user-facing" controls for this as a content creator. You get what you get.  Now, if you are NBC, they might give you a little more control (but from what I've heard at NAB, not much at all).  They NEVER use your source footage directly, even if it is "web-friendly" compressed already.

So, the takeaway is this:  If YouTube is offering a "1080p" version, then the content creator gave them a 1080p source (or better).  If it was upscaled, the content creator did it, not YouTube.

If I had to guess?  It is probably being shot either at 4-5k on a digital cinema camera of some kind (maybe a RED Epic?) or it is being shot on DVCProHD, Sony's format (whatever it is called now), or AVCIntra gear at 1080p of some variety.  Probably a mix of both depending on the event, actually.

It doesn't much matter though because then YouTube takes the nice quality source they give them, and they beat the living daylights out of it and serve you crap.  If you drop down to the lower quality one on YouTube?  It might actually be better (if the bits-per-pixel available in the compression algorithm are more favorable) or it might be worse (if they use even crappier settings for lower-res stuff, figuring it is web video and who cares).

YouTube's compression system is a black box though, and what they did last week might not be the same as what they do now.

That's why Vimeo is so much better.

[glynor]

PS. Canon's HDV cameras were very popular for shooting sports a while back, but most pro shooters didn't actually use the HDV tapes.  They just used the cameras as cameras, and used the component output jack to run into something like the AJA Ki Pro to record.  If you do it that way, HDV never touches the footage.  You're just getting the raw sensor data (which may or may not be 1920x1080 itself, depending on the sensor).  In any case, at least it isn't recompressed and you can capture it yourself to a good codec.

This is still a very cheap way to get very high quality footage.  You can buy a very cheap consumer camcorder that has a HDMI out port on it, plug it into a Ki Pro (or Ki Pro Mini) and get AWESOME quality footage out of it without suffering the horrific consumery compression system they put on it to fit the footage onto the little tapes or SD cards they give you with those junk camcorders.

[jgreen]

Thanks for noggining in on this, Glynor.  Your point about HDV being flat on the chroma is what set me on this warpath to begin with.  No halations, just remarkably flat chroma. 

Also, it now clicks in my skull that YT is reconverting most videos.  I have seen this, and just assumed that they were heavily uprezzed, but the artifacting was of the nature of "blocks within blocks" (I'm not trying to describe pixellation here).

Lastly, you really should cruise over there and look at some of the "official" sites, for example "Olympic".  There is plenty of dead sexy 1920X1080 HD to be had there.  Yes, you can find quantizing in the vignette, but we're livin in a new age here, Hermanito.  Twenty years ago the bourgeoisie owned all media; now we can get kittens playing with strings and puppydogs surfing any time any where!