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Agency Based Discussion => General - Top Sites => Topic started by: grejak on November 16, 2019, 06:16

Title: 4096 x 2160p vs 3840x2160
Post by: grejak on November 16, 2019, 06:16
Recently i have upgraded my camera gear just for stock, and i have noticed that when i upload 4096 resolution the buyers get option for full HD in bigger resolution than 1920x1080. my question is, is it worth uploading 4096 or stick to UHD? Thanks
Title: Re: 4096 x 2160p vs 3840x2160
Post by: bestravelvideo on November 16, 2019, 07:06
With 4K DCI you get a bit more horizontal pixels which in theory, in numbers, is better.
You see your HD resolution change because the aspect ratio you record is 16:10, not 16:9.
This means that if someone needs to fit your video, regardless of resolution, to a UHD or HD project, he will probably crop some pixels. Maybe you need to shoot a bit wider to cover this possibility.
Almost the same is valid if you are using Super 35 mm mode.
Also, check if you record exactly 24 fps instead of 23,976.
Just a thought to conclude: Since 4K DCI is considered cinema mode and probably records at higher bitrate, you might benefit in stock from that if you shoot content that might fit a documentary or film production.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: grejak on November 16, 2019, 07:12
With 4K DCI you get a bit more horizontal pixels which in theory, in numbers, is better.
You see your HD resolution change because the aspect ratio you record is 16:10, not 16:9.
This means that if someone needs to fit your video, regardless of resolution, to a UHD or HD project, he will probably crop some pixels. Maybe you need to shoot a bit wider to cover this possibility.
Almost the same is valid if you are using Super 35 mm mode.
Also, check if you record exactly 24 fps instead of 23,976.
Just a thought to conclude: Since 4K DCI is considered cinema mode and probably records at higher bitrate, you might benefit in stock from that if you shoot content that might fit a documentary or film production.


May i ask you what is the difference between 24fps and 23,976 thanks for the help !
Title: Re: 4096 x 2160p vs 3840x2160
Post by: Zero Talent on November 16, 2019, 07:49
With 4K DCI you get a bit more horizontal pixels which in theory, in numbers, is better.
You see your HD resolution change because the aspect ratio you record is 16:10, not 16:9.
This means that if someone needs to fit your video, regardless of resolution, to a UHD or HD project, he will probably crop some pixels. Maybe you need to shoot a bit wider to cover this possibility.
Almost the same is valid if you are using Super 35 mm mode.
Also, check if you record exactly 24 fps instead of 23,976.
Just a thought to conclude: Since 4K DCI is considered cinema mode and probably records at higher bitrate, you might benefit in stock from that if you shoot content that might fit a documentary or film production.


May i ask you what is the difference between 24fps and 23,976 thanks for the help !

23.976 = 24 - 0.1%
The frame rate standard has been slightly adjusted, long ago, when NTSC was launched.
Engineers noticed that color was interfering with the black and white information. The reduction of the framerate by 0.1% was tolerated by the existing black and white TV systems and addressed the interference.

Similarly, 29.97fps = 30fps - 0.1%
Title: Re: 4096 x 2160p vs 3840x2160
Post by: grejak on November 16, 2019, 08:00
With 4K DCI you get a bit more horizontal pixels which in theory, in numbers, is better.
You see your HD resolution change because the aspect ratio you record is 16:10, not 16:9.
This means that if someone needs to fit your video, regardless of resolution, to a UHD or HD project, he will probably crop some pixels. Maybe you need to shoot a bit wider to cover this possibility.
Almost the same is valid if you are using Super 35 mm mode.
Also, check if you record exactly 24 fps instead of 23,976.
Just a thought to conclude: Since 4K DCI is considered cinema mode and probably records at higher bitrate, you might benefit in stock from that if you shoot content that might fit a documentary or film production.


May i ask you what is the difference between 24fps and 23,976 thanks for the help !

23.976 = 24 - 1%
The frame rate standard has been slightly adjusted, long ago, when NTSC was launched.
Engineers noticed that color was interfering with the black and white information. The reduction of the framerate by 1% was tolerated by the existing black and white TV systems and addressed the interference.

Similarly, 29.97fps = 30fps - 1%

thanks ! I am shooting on blackmagic URSA 4k V2, i believe it's shooting in 24p what do you suggest?
Title: Re: 4096 x 2160p vs 3840x2160
Post by: bestravelvideo on November 16, 2019, 08:02
To put it in a sentence, 24 fps is considered a cinema standard while 23.976 a Broadcast TV one.
If you are thinking of how to cover both cases, maybe just shoot at 23.976 but I don't know if you can do that at 4K DCI in your camera.
The long explanation would involve details about how smooth each plays and which converts better to another format like a Blu-Ray or 25 fps.
Now that with DVB-T digital TV we have no more PAL or SECAM most series air in 1080i.
At the end it sounds confusing: Why use a DCI camera while most would just need to buy UHD?
Maybe you get an enhanced stock sale in case someone as I mentioned needs a video for a bigger budget production and yours fits their project.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: bestravelvideo on November 16, 2019, 08:09
What is important about your camera is that it has a global shutter and you can shoot DNG RAW video.
This is great if you know how to colour correct your material.
Such a video quality does magic in post production!
Your video can fit any broadcast need and passes the requirements for a documentary production.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: grejak on November 16, 2019, 08:22
What is important about your camera is that it has a global shutter and you can shoot DNG RAW video.
This is great if you know how to colour correct your material.
Such a video quality does magic in post production!
Your video can fit any broadcast need and passes the requirements for a documentary production.

Is it logical to shoot in 4096x2160 in 24p then? Or can i just export it in 23,976? Also forgot to mention my camera only shoots in 4000x2160 which is weird format. is it okay to upscale to 4096. Thank you so much for this help, trying to get the best possible out of this camera it wasnt cheap ! Also the image quality indeed is awesome and i am learning everyday how to grade it even better ! It was an amazing upgrade.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: bestravelvideo on November 16, 2019, 09:44
Then one suggestion would be you rec with Apple ProRes 422 HQ codec at 3840x2160.
Check if this is at 23,976 but since the codec is fixed it will use a crazy high bitrate.
Will your computer be able to process that? It is still broadcast quality with no visible loss.
It goes to 880 Mbps or you need to read and search how you can work and edit with proxy files.
I work as a Broadcast TV editor and can confirm that most TV studios deliver series or movies for TV in that format and codec.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: increasingdifficulty on November 16, 2019, 09:48
Is it logical to shoot in 4096x2160 in 24p then? Or can i just export it in 23,976?

For the buyer, 23.976 or 24 matters exactly zero (0), since a clip without audio can be played at 23.976, 24, or even 25 without any noticable difference. It is 1 click (OK, maybe 2 or 3) in any software.

If you provide 23.976, and their project is 24, it means they will play your clip 0.1% faster. This is how it's done every day in Europe (and the rest of the PAL world) with 24p movies. They all play back at 25p (4% faster).
Title: Re: 4096 x 2160p vs 3840x2160
Post by: Desintegrator on November 16, 2019, 10:00
Is it logical to shoot in 4096x2160 in 24p then? Or can i just export it in 23,976?

For the buyer, 23.976 or 24 matters exactly zero (0), since a clip without audio can be played at 23.976, 24, or even 25 without any noticable difference. It is 1 click (OK, maybe 2 or 3) in any software.

If you provide 23.976, and their project is 24, it means they will play your clip 0.1% faster. This is how it's done every day in Europe (and the rest of the PAL world) with 24p movies. They all play back at 25p (4% faster).

yes, the difference between 23.976 and 24 is 1 frame in 1000 frames. Most stock videos are not even 1000 frames long
Title: Re: 4096 x 2160p vs 3840x2160
Post by: grejak on November 16, 2019, 10:10
Then one suggestion would be you rec with Apple ProRes 422 HQ codec at 3840x2160.
Check if this is at 23,976 but since the codec is fixed it will use a crazy high bitrate.
Will your computer be able to process that? It is still broadcast quality with no visible loss.
It goes to 880 Mbps or you need to read and search how you can work and edit with proxy files.
I work as a Broadcast TV editor and can confirm that most TV studios deliver series or movies for TV in that format and codec.

Well i can edit RAW 4000x2160. i can try if i can work with 422 HQ. But i work on windows. so i export with dnxdh codec and then change it to 422 HQ on media encoder 2019? But with 422 i get only 10bit picture, there would be option to record on 4444 but * this does that a lot of space even more than RAW
Title: Re: 4096 x 2160p vs 3840x2160
Post by: grejak on November 16, 2019, 10:12
Is it logical to shoot in 4096x2160 in 24p then? Or can i just export it in 23,976?

For the buyer, 23.976 or 24 matters exactly zero (0), since a clip without audio can be played at 23.976, 24, or even 25 without any noticable difference. It is 1 click (OK, maybe 2 or 3) in any software.

If you provide 23.976, and their project is 24, it means they will play your clip 0.1% faster. This is how it's done every day in Europe (and the rest of the PAL world) with 24p movies. They all play back at 25p (4% faster).

great so the fps don't matter that much but what about resolution, what's your opinion 4096 or UHD?
Title: Re: 4096 x 2160p vs 3840x2160
Post by: bestravelvideo on November 16, 2019, 11:47
You can shoot 4096 and then crop to 3840.
It's like you scale down in photos. It will or might look a bit clearer, wit less noise.
Also, you can crop the edges a bit and still export in 3840 so that would not be digital zoom.
Another point is that in case you use warp stabilise you still benefit from that.
A video editor would know what to do with that resolution.
The rest might even not know the difference from different aspects or fit the video to a preset and still scale it to their preference.
All these might be more than needed for stock.
If you are using the camera for ads or other no-stock productions, better you stick to Cinema DNG and play with the colours in post.
Finally, if you are using Premiere, you can export on ProRes, already available from the previous version.
Plain ProRes (not HQ) is more than enough for stock. Just don't use LT.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: ForrestBrown on November 16, 2019, 14:32
Recently i have upgraded my camera gear just for stock, and i have noticed that when i upload 4096 resolution the buyers get option for full HD in bigger resolution than 1920x1080. my question is, is it worth uploading 4096 or stick to UHD? Thanks

You probably want to upload your footage as UHD. All of the stock sites will take your UHD footage and scale it down to make HD (and sometime web) options for people to download if they don't want to buy the full 4K versions. Most sites do not make HD versions based on 4096 footage. I personally shoot 4096 and crop it to UHD. That gives me some flexibility to slightly reframe the shot if I want.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: ForrestBrown on November 16, 2019, 14:37
You can shoot 4096 and then crop to 3840.
It's like you scale down in photos. It will or might look a bit clearer, wit less noise.

Going from 4096 to 3840 is just a crop, there's no scaling. Both are 2160 pixels tall.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: grejak on November 16, 2019, 18:06
You can shoot 4096 and then crop to 3840.
It's like you scale down in photos. It will or might look a bit clearer, wit less noise.
Also, you can crop the edges a bit and still export in 3840 so that would not be digital zoom.
Another point is that in case you use warp stabilise you still benefit from that.
A video editor would know what to do with that resolution.
The rest might even not know the difference from different aspects or fit the video to a preset and still scale it to their preference.
All these might be more than needed for stock.
If you are using the camera for ads or other no-stock productions, better you stick to Cinema DNG and play with the colours in post.
Finally, if you are using Premiere, you can export on ProRes, already available from the previous version.
Plain ProRes (not HQ) is more than enough for stock. Just don't use LT.

yeah but at the moment i am using davinci resolve in which i can't export in prores 422 but i can use media encoder later on. so what do you suggest i export in davinci on windows?
Title: Re: 4096 x 2160p vs 3840x2160
Post by: grejak on November 16, 2019, 18:07
Recently i have upgraded my camera gear just for stock, and i have noticed that when i upload 4096 resolution the buyers get option for full HD in bigger resolution than 1920x1080. my question is, is it worth uploading 4096 or stick to UHD? Thanks

You probably want to upload your footage as UHD. All of the stock sites will take your UHD footage and scale it down to make HD (and sometime web) options for people to download if they don't want to buy the full 4K versions. Most sites do not make HD versions based on 4096 footage. I personally shoot 4096 and crop it to UHD. That gives me some flexibility to slightly reframe the shot if I want.

but why do you crop it from 4096 to UHD why just not upload the full size?
Title: Re: 4096 x 2160p vs 3840x2160
Post by: ForrestBrown on November 16, 2019, 18:57
Recently i have upgraded my camera gear just for stock, and i have noticed that when i upload 4096 resolution the buyers get option for full HD in bigger resolution than 1920x1080. my question is, is it worth uploading 4096 or stick to UHD? Thanks

You probably want to upload your footage as UHD. All of the stock sites will take your UHD footage and scale it down to make HD (and sometime web) options for people to download if they don't want to buy the full 4K versions. Most sites do not make HD versions based on 4096 footage. I personally shoot 4096 and crop it to UHD. That gives me some flexibility to slightly reframe the shot if I want.

but why do you crop it from 4096 to UHD why just not upload the full size?

I said why at the beginning of what I wrote.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: Cider Apple on November 16, 2019, 19:35
Most sites do not make HD versions based on 4096 footage. I personally shoot 4096 and crop it to UHD. That gives me some flexibility to slightly reframe the shot if I want.

I've never experienced this Forrest? I've been uploading 4096 to all the major stock sites for years and they scale down to HD fine.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: ForrestBrown on November 16, 2019, 21:12
Most sites do not make HD versions based on 4096 footage. I personally shoot 4096 and crop it to UHD. That gives me some flexibility to slightly reframe the shot if I want.

I've never experienced this Forrest? I've been uploading 4096 to all the major stock sites for years and they scale down to HD fine.

Have to admit it's been a couple of years since I tried, but there definitely was a couple sites I was submitting to that would not to the down converted HD if you uploaded 4096. Maybe I'll have to give another try.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: ODesigns on November 16, 2019, 21:27
I always shoot 4096 whenever I can. A buyer can always "downsize" to 3840, but a buyer who needs/wants 4096 probably wouldn't buy a 3840 clip.

Most agencies downsize 4096 to HD while keeping the proportions, so a 4096x2160 clip will be 2048x1080 in HD, which is also totally acceptable (and considered "2K").  Even then, the buyer can easily drop it into a "normal" 1920x1080 timeline.  Some agencies crop 4096 to a standard 1920x1080, which is fine, but I like giving the buyer the option to have 2048.

And no, don't upscale 4000x2160 to 4096x2160.  If you can't shoot 4096, then upload as 4000, or crop to 3840 yourself.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: grejak on November 17, 2019, 05:30
I always shoot 4096 whenever I can. A buyer can always "downsize" to 3840, but a buyer who needs/wants 4096 probably wouldn't buy a 3840 clip.

Most agencies downsize 4096 to HD while keeping the proportions, so a 4096x2160 clip will be 2048x1080 in HD, which is also totally acceptable (and considered "2K").  Even then, the buyer can easily drop it into a "normal" 1920x1080 timeline.  Some agencies crop 4096 to a standard 1920x1080, which is fine, but I like giving the buyer the option to have 2048.

And no, don't upscale 4000x2160 to 4096x2160.  If you can't shoot 4096, then upload as 4000, or crop to 3840 yourself.

Great ! i was thinking the same as you. And yeah i've noticed that most agencies drop a 4096 clip to 2048 for HD. And how are the sells do you sell many 4k videos if it's not a secret?
Why shouldn't i upscale? Isn't it just a small difference, i know people that have alexa and shoot in 3k and just upscale it to 4k. Because 4000x2160 seems unasable for me. they can't use it for 4096 so i just better crop it to UHD
Title: Re: 4096 x 2160p vs 3840x2160
Post by: ODesigns on November 17, 2019, 07:56
You're right, it's only 96 pixels, but you should always give the customer the best quality possible.  And even upping 96 pixels does degrade the quality a little.  It would be a bad habit to get into.

But, even if you did, I doubt anyone would know.  If you do up it, up it proportionally.  Don't just "stretch" the horizontal to reach 4096.

If anything, upload native 4000x2160 and let the customer upsize it if they want.  But, some agencies might not like the non-standard 4000 pixel horizontal resolution.

I do well with 4K.  So far this month, I sold 16 of them.  But HD probably makes up about 90% of my downloads.  I even had 2 SD sales this month, so resolution really isn't the key factor when a buyer decides what clip to get -- it's content.
 
Title: Re: 4096 x 2160p vs 3840x2160
Post by: grejak on November 17, 2019, 08:05
You're right, it's only 96 pixels, but you should always give the customer the best quality possible.  And even upping 96 pixels does degrade the quality a little.  It would be a bad habit to get into.

But, even if you did, I doubt anyone would know.  If you do up it, up it proportionally.  Don't just "stretch" the horizontal to reach 4096.

If anything, upload native 4000x2160 and let the customer upsize it if they want.  But, some agencies might not like the non-standard 4000 pixel horizontal resolution.

I do well with 4K.  So far this month, I sold 16 of them.  But HD probably makes up about 90% of my downloads.  I even had 2 SD sales this month, so resolution really isn't the key factor when a buyer decides what clip to get -- it's content.
 

Great thanks for info ! How do you upscale it correctly? Just zoom in and lose some pixels on top? also thanks for the info about sells this means that people can still use 2048x1920. thanks !
Title: Re: 4096 x 2160p vs 3840x2160
Post by: ODesigns on November 17, 2019, 10:47
I don't know what program you're using, but in AE, you can right-click on the clip in your composition and choose:

1. Transform
2. Fit to Comp Width

It will calculate the proper size and proportionally upscale your clip.  And yes, it will chop of a little on the top and bottom, but that would be minimal.

Just make sure your composition in AE is 4096x2160.

Or, just scale up to 102.4%.

Title: Re: 4096 x 2160p vs 3840x2160
Post by: PeterChigmaroff on November 17, 2019, 20:10
You're probably overthinking this one. We see lost sales because the clip isn't 4k, because it's not ProRes or better, because it's not 23.98 or 24 but I've never had anyone ever ask for C4k over UHD or the other way around.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: increasingdifficulty on November 18, 2019, 08:47
You're probably overthinking this one.

I agree.

We see lost sales because the clip isn't 4k, because it's not ProRes or better, because it's not 23.98 or 24 but I've never had anyone ever ask for C4k over UHD or the other way around.

Do you mean that buyers have contacted you, asking for ProRes, 4k, and/or 23.98p and you didn't have it, and therefore they didn't buy? Or do you THINK you lost sales?

---

The last three months I've sold around 50 clips on Pond5.

94% were HD.

6% 4k.

36% of the HD sales had 4k (ProRes) versions available. 64% were HD native.

---

From this small sample I can just assume that MOST buyers don't care about 4k, at least not enough to spend more $$$. They also MIGHT not care that much about getting ProRes since the h264 downconverted versions worked fine.

Of course, very small sample, and I don't have time to go back further right now, but right now it seems HD h264 is still fine for most, with a few "advanced" buyers wanting 4k.

The download time alone for, say, 30 ProRes HQ 4k clips would be a couple of hours, which may or may not be too slow for some customers.

---

Just a bit of guesswork here... Anyone with conflicting data?
Title: Re: 4096 x 2160p vs 3840x2160
Post by: ODesigns on November 18, 2019, 09:05
For most stock buyers, codec doesn't matter.  Frame rate doesn't matter.  Resolution doesn't matter.

What matters is the content.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: PeterChigmaroff on November 18, 2019, 12:05
You're probably overthinking this one.

I agree.

We see lost sales because the clip isn't 4k, because it's not ProRes or better, because it's not 23.98 or 24 but I've never had anyone ever ask for C4k over UHD or the other way around.

Do you mean that buyers have contacted you, asking for ProRes, 4k, and/or 23.98p and you didn't have it, and therefore they didn't buy? Or do you THINK you lost sales?

---

The last three months I've sold around 50 clips on Pond5.

94% were HD.

6% 4k.

36% of the HD sales had 4k (ProRes) versions available. 64% were HD native.

---

From this small sample I can just assume that MOST buyers don't care about 4k, at least not enough to spend more $$$. They also MIGHT not care that much about getting ProRes since the h264 downconverted versions worked fine.

Of course, very small sample, and I don't have time to go back further right now, but right now it seems HD h264 is still fine for most, with a few "advanced" buyers wanting 4k.

The download time alone for, say, 30 ProRes HQ 4k clips would be a couple of hours, which may or may not be too slow for some customers.

---

Just a bit of guesswork here... Anyone with conflicting data?

I'm sure your stats are accurate. We have lost sales to poor codecs, to being HD and to not having the desired frame rate but never to a clip being UHD. We had the right clip with wrong tech specs. We also see requests for specific frame rates, codecs and resolution but I've not seen one that specified C4k. I don't acutally think there is an overall best practices to all this. Just pleasing some of the people most of the time. You choose who those people are.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: Desintegrator on November 18, 2019, 13:12
I've just realized the HD downsampled versions of 4K clips are offered with very small file sizes Shutterstock.
A 10second clip is 8 Megabytes. That's around 6mbit/s bitrate.

Isn't that unacceptably low? I cannot imagine providing useful quality for further processing in that size. That should be around Youtube quality which is sometimes questionable even for final delivery. And stock clips should be considered like raw material for further processing.

I always have the intention to provide HD clips in 100mbit/s the minimum
Title: Re: 4096 x 2160p vs 3840x2160
Post by: increasingdifficulty on November 18, 2019, 13:36
I've just realized the HD downsampled versions of 4K clips are offered with very small file sizes Shutterstock.
A 10second clip is 8 Megabytes. That's around 6mbit/s bitrate.

Where do you see that? I see from around 25-80 mbit/sec depending on the content.

100 mbit for HD is good, but in reality, NEAR perfect quality can be obtained with 100 mbit for 4k, which most smaller cameras film with (GH4/GH5 100/150 mbit) and that 4k quality is quite pristine. No, not as good as a ProRes capture of course, but very good.
Title: Re: 4096 x 2160p vs 3840x2160
Post by: Desintegrator on November 18, 2019, 14:30
I've just realized the HD downsampled versions of 4K clips are offered with very small file sizes Shutterstock.
A 10second clip is 8 Megabytes. That's around 6mbit/s bitrate.

Where do you see that? I see from around 25-80 mbit/sec depending on the content.

100 mbit for HD is good, but in reality, NEAR perfect quality can be obtained with 100 mbit for 4k, which most smaller cameras film with (GH4/GH5 100/150 mbit) and that 4k quality is quite pristine. No, not as good as a ProRes capture of course, but very good.

If i click on my older 4k clips, the HD version file size is around 100-200 Megabytes
On clips uploaded nowadays it's 8-10 Megabytes...

I understand that 100 mbit/s is not absolutely necessary for good quality HD, but 6 seems way too low
Title: Re: 4096 x 2160p vs 3840x2160
Post by: Desintegrator on November 18, 2019, 14:34
I've just realized the HD downsampled versions of 4K clips are offered with very small file sizes Shutterstock.
A 10second clip is 8 Megabytes. That's around 6mbit/s bitrate.

Where do you see that? I see from around 25-80 mbit/sec depending on the content.

100 mbit for HD is good, but in reality, NEAR perfect quality can be obtained with 100 mbit for 4k, which most smaller cameras film with (GH4/GH5 100/150 mbit) and that 4k quality is quite pristine. No, not as good as a ProRes capture of course, but very good.

If i click on my older 4k clips, the HD version file size is around 100-200 Megabytes
On clips uploaded nowadays it's 8-10 Megabytes...

I understand the 100 mbit/s is not absolutely necessary for good quality HD, bzt 6 seems way too low

Ok, my very recently uploaded clips have bigger file sizes for HD versions again. Looks like there was a period recently when SS converted them really low. I have even a 18 second clip where the HD version is just 6.1 MB
Title: Re: 4096 x 2160p vs 3840x2160
Post by: Desintegrator on November 18, 2019, 14:35
Also noticed that 4096*2160 is downsized to 2047*2160 instead of 2048.
Couldn't that deter buyers? It's strange to have an odd-numbered dimension. I don't if such problems exist today, but around 15 years ago when I first had to deal with video codecs and such there were some codecs and some editing software where the dimensions of the clips had to be divisible by 8. (which basically every standard video resolution is)