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yuri_base

The Question of the Universe: why video pixels are not square?

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Ok, fuck me dead, but I don't understand one simple thing: why, oh why, after three decades of desktop video production, we still see and fight the stupid issue of aspect ratio?!?! Meaning, you post a video somewhere or watch the video and its aspect ratio is distorted from normal?

Why oh why in the era of artificial intelligence, the computers still cannot make square pixels be square in videos?!

Why oh why the last time you saw an image with distorted aspect ratio when you used Netscape Navigator 1.0 and yet 20 years later the video is still hit and miss?! What is it so special about video, compared to stills?!

WTF?

WTF?

WTF?

(I'm just tired of uploading a video, say to youtube or vimeo, for many times before seeing really square pixels. Jeez, life doesn't have to be that hard! ;))

Ok, I feel better now. :ph34r:
Android+Wear/iOS/Windows apps:
L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP
iOS only: L/D Magic
Windows only: WS Studio

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Cuz the play back heads are rounded in your camera dude and if the pixels were square they wouldn't fit through the play back heads and your video output ports would get all jammed up in there and clog up your camera....... DUH!
:P;)
you can't pay for kids schoolin' with love of skydiving! ~ Airtwardo

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Dude, it's because they are flocking and trying to make the grid fit the formation.....thats why you get all the distortion. If your videos pixels would just straighten their legs and increase their L/D it would all work out.:D;):P
"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

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There are plenty of cameras that record video with square pixels. Check the specs before you buy.



Actually most cameras shoot different pixel aspect ratios (silly webcams aside).
Though capturing/editing footage, you do have a wide range of choice in conversions to square pixels.

But aside from the un-easy feeling of seeing non 16:9 vallues in terms of pixel aspect ratio, for your 16:9 footage, there isnt much actual hindrance or even vague notice of its non-square-ness in editing...;)
JC
FlyLikeBrick
I'm an Athlete?

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Buy my book "The Full HD" and I explain it in great detail.
Umm....MOST HD broadcast isn't square pixels, MOST camcorders do not capture square pixels.
All of the web is square pixels.
MOST of the people posting video to the web are clueless about PAR (Pixel Aspect Ratio).

Thank god there are still professionals left in the video biz who actually get it, know how to deal with it, and can post it accurately.
Unfortunately, Apple devices really f**k this for the rest of the world, which is why most morons post the wrong PAR.

.909, .85, then you start tossing in SAR on top of PAR, especially DV acquired at 4:3 SAR and output as 16:9, and you get a helluva mess.

Keep asking, Yuri. I hear a cha-ching with every question. :)
BTW, the problem with pixels isn't the media, it's the operator.

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Thanks for answering The Question of the Universe, DSE. I must admit: of all operators in the world, I'm the dumbest one. :D Case in point: ok, I understand that some sensors have non-square PAR, but obviously the software (usually supplied by the camera manufacturer) that uploads the raw data from camera and converts it to video viewable on a computer, takes care of that. At this point, pixels become square. So one would expect at this point that no matter in which PC-compatible format you save the video (by "PC" I mean personal computer, not necessarily Windows/Mac OS/Linux/whatever), it'll maintain that.

Just like with still pictures. You upload them from camera and you see them perfectly aspect-ratio'd and no matter in which format - JPEG, PNG, TIFF, BMP, etc. - you save it and no matter which site you upload them, you never have to worry about aspect ratio. Pictures are never mis-aspect-ratio'd.

But you take a video that's playing perfectly aspect-ratio'd on your computer and upload it to youtube, boom! - you see some weird distortion. In this time and age, why we still have to fight this stupid thing? Once the video is in the computer, it should maintain aspect ratio no matter how you massage it. There must be some Mafia behind all this to make stupid people like me suffer and search for answers to the question of the Universe from professionals. ;)
Android+Wear/iOS/Windows apps:
L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP
iOS only: L/D Magic
Windows only: WS Studio

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Umm....MOST HD broadcast isn't square pixels, MOST camcorders do not capture square pixels.



I don't think anybody in this thread claimed either of those things.

The fact remains that a very popular camera for skydiving right now DOES have square pixels, so if you want to whine about not having them (as Yuri is), it might be easier just to get that camera, or one of the others that do. :)
www.WingsuitPhotos.com

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Sensors may (often do) have non-square pixel resolutions, but the real rub is in the storage. For example...Canon HDV camcorders have full resolution/square pixel imagers/sensors, but record the media at 1440x1080.
Why? To save bandwidth. By using non-square pixels (as does the world-standard HD production format known as HDCAM), bandwidth is reduced by 25% out of the gate. More bandwidth=less compression for equal image quality.
Make sense?
Here's the secret to working with non-square pixels if you don't wanna know the math for uploads.
Always set your project settings in your NLE to display square pixels and not compensate for PAR.
or...read my tutorial on uploading.
Work at:
1280 x 720, 864x486, 640x360, 480x270, and 320x180 and you'll be happy (assuming you're uploading widescreen.
Please put a quarter in your CD tray and email it to me. I'm expensive when it comes to sharing knowledge.

Matt, it's easy to say "get a square imager/full resolution camera," but that won't solve Yuri's issue if he's uploading anything but 1920 x 1080, and even then, Flash encoders can screw it up (but they usually don't).

Frankly, I prefer 1440 x 1080 when dealing with identical bandwidth. The move to 1920 x 1080 imagers for AVC was purely a marketing move, and no one really sees benefit unless the bandwidth is cranked up to 24Mbps, and even then...1440x1080 is gonna be a delivery standard for many, many years to come.

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CX100? 1920x1080. That's square pixels, right?



Most cameras display (on tv) at 1920x1080, but actually store the information at 1440x1080 (non square).
(DSE correct me if Im wrong) CX100/105 can (at Uber-HQ mode) store the information at 1920x1080. But Im not sure what the resolution is that the images is capturing?
The highest quality/bitrate aside, in all other modes it shoots 1440x1080. When editing, hardly anyone notices the difference though...so for most, not a thing to worry about..

Pre-sets and 'Wizards' have taken the fun out of that subject:P
JC
FlyLikeBrick
I'm an Athlete?

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CX100? 1920x1080. That's square pixels, right?



Most cameras display (on tv) at 1920x1080, but actually store the information at 1440x1080 (non square).
(DSE correct me if Im wrong) CX100/105 can (at Uber-HQ mode) store the information at 1920x1080. But Im not sure what the resolution is that the images is capturing?
The highest quality/bitrate aside, in all other modes it shoots 1440x1080. When editing, hardly anyone notices the difference though...so for most, not a thing to worry about..

Pre-sets and 'Wizards' have taken the fun out of that subject:P



You're pretty close on the above, Jarno.
*most* HD cams store at a size different than the display size, but the CX100/105 store (in all HD modes) at 1920 x 1080 pixels.
Before everyone gets excited tho, full rez storage from a 1/5 imager is very different than full rez storage from say...a .5 or .66 imager. It's also why low light is a challenge for all the small HD cameras. NONE of them have great low light.

Displays see the incoming signal and upconvert to full raster images. Panasonic is the king of fudging pixels, as they are the only company that fudges with both vertical AND horizontal resolution, while Sony, Canon, Grass Valley, Ikegami, JVC only mess with horizontal resolution (if any fudging is being done).
Broadcast HD is *usually* 1440 x 1080, but in some areas of the world, it's only 1280 x 720 (which is always square pixels).

Didn't mean to write a novella, and trying really hard to avoid the techno-speak that seems to piss a few people off.

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In the end its all the imager that determines the look.
A 640x480 picture from my telephone saved/sored as 10 megapixel shares the same technical specs in data....though a difference of night and day in quality...

That aside...I use the 9mbs HD HQ (one step lower than super-duper 12 mbs setting) and seem to get 1440x1080 .m2t files out of that one.

Editing on a mac, final cut may do a 1920x1080 conversion, but sure not getting that resolution from my camera when I look at the specs of the raw footage..
JC
FlyLikeBrick
I'm an Athlete?

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