Trouble with selecting a video resolution with Handbrake...

[Ronaldinho]

Hi everyone,

I've never had this problem before because ever since I've started using Handbrake I have only been encoding HD video, so the resolution would always be 1280x720 or 1920x1080, but I have a DVD here that I've just ripped, and now I want to encode it, and obviously it's not HD, so I googled for 16:9 resolutions because the only SD ones I really know of are 640x360 and 704x400 (which I don't like because it's not exactly 16:9) and I found this list...

http://pacoup.com/2011/06/12/list-of-true-169-resolutions/

But the problem is that every time I try one of those resolutions, handbrake changes it to something slightly (and sometimes very) different to what I entered. It's really annoying... I have Anamorphic set to "None", in case anyone is wondering... I just don't know why it's not letting me do it.

I tried 640x360, and it changed it to 640x368, I tried 704x396, and it changed it to 704x400 and so on...

Can someone please tell me what I'm doing wrong?

Thanks.

[Baldrick]

Handbrake is probably only using mod16 resolution. The width and height are evenly divisible by 16. It's usually recommended to use such resolutions for best quality.

[Ronaldinho]

okay, but why is it that all the mod16 resolutions Handbrake is giving me, don't seem like proper 16:9 aspect ratio? Because they don't fully fit my 16:9 screen (they almost do, but not quite)...

[Hoser Rob]

Handbrake isn't the only encoder that'll do that. Avidemux does it sometimes. I'd do as baldrick suggested and use the mod 16 resolution. You'll never notice the difference when watching the video.

[Ronaldinho]

Handbrake isn't the only encoder that'll do that. Avidemux does it sometimes. I'd do as baldrick suggested and use the mod 16 resolution. You'll never notice the difference when watching the video.

Okay, fair enough.

Thanks guys.

[jagabo]

If you don't like mod 16 change the Modulus setting in Handbrake.

[Ronaldinho]

Okay, but what are the disadvantages of not using mod16?

[jagabo]

Okay, but what are the disadvantages of not using mod16?

Slightly less encoding efficiency in encoding/decoding speed and compression/quality. Some old players will have decoding problems.

[Ronaldinho]

hmm.. Okay. Well, are there any SD mod16 resolutions that you know of that are proper 16:9? Because I just encoded my DVDrip with a resolution of 704x400, and I'd still prefer a resolution that will fit my full screen...

Thanks again for your help.

[mike20021969]

I'd avoid mod16. Although not by much, it distorts aspect ratio.
I always use mod2.

[Ronaldinho]

I'd avoid mod16. Although not by much, it distorts aspect ratio.
I always use mod2.

So there are no mod16 resolutions that can keep a proper 16:9 aspect ratio? Or at least no SD resolutions?

[jagabo]

So there are no mod16 resolutions that can keep a proper 16:9 aspect ratio? Or at least no SD resolutions?

Sure there are:

9*16*1 = 144, 16x16*1 = 256
9*16*2 = 288, 16x16*2 = 512
9*16*3 = 432, 16x16*3 = 768

[Ronaldinho]

Okay, I tried to do 768x432, but handbrake won't allow a resolution any higher than the source... 512x288 is too low for my liking. I guess I will just have to settle for a lower modulus, or 704x400.

Thanks again for everyone's help. Much appreciated.

[jagabo]

I normally keep the original frame size (only cropping black borders) and use aspect ratio flags.

[Ronaldinho]

Okay, this whole mod16 thing is making me confused...

Since Handbrake is automatically changing any resolution that I select to a mod16 resolution (e.g. 704x396 to 704x400), why then is it automatically changing my 1920x1080 source video to 1920x1088? Is 1920x1080 not a mod16 resolution? And if not, then why is it used in blu-rays that are h.264 encoded?

Note: For some reason Handbrake WILL allow me to manually select 1920x1080, but not without it choosing 1920x1088 first. Basically, what it does is.. when I open a 1920x1080 video in handbrake, it changes the resolution to 1920x1088, but it will allow me to then change it back to 1920x1080. However, the reason I find this strange is because it won't allow me to manually select any other resolution that is not mod16...

I hope people can understand what I'm trying to say...

Basically, is 1920x1080 mod16, and if it isn't, then why does handbrake allow me to manually select that resolution while having Mod16 selected.

I'm so confused...

[jagabo]

Mod 16 means an integer multiple of 16. 1080 is not an integer multiple of 16.

[poisondeathray]

It's just going to confuse you more, but 1920x1080 is actually internally padded and encoded as 1920x1088, there is a crop flag in the h.264 bitstream that is standard for that resolution, so it displays as 1920x1080

[jagabo]

Note that Blu-ray defined what was required of players. So requiring that they be able to handle a non-mod16 frame size wasn't a problem. 1920x1080, as stupid as it is, was the standard defined by HDTV around the world. Blu-ray went along with it.

[Ronaldinho]

Okay, okay. So, this brings to mind another question...

I've been capturing live football (soccer) matches on my PC over the last few months in HD 1080i, and encoding them to 1080p (1920x1080). Should I have been encoding them as 1920x1088 instead?

Note: I always had to crop just a tiny bit usually on the top and bottom of the picture to remove some black borders, and yes, i am aware that the TV would stretch these black parts and you wouldn't notice them, but you do on a PC, so that's why i crop them out. Is this a bad idea if I'm encoding to 1920x1080 instead of 1920x1088?

Once again, thanks for the help.

[jagabo]

Almost everything plays mod8 (1080) properly -- because that's the HDTV standard.

[Ronaldinho]

Almost everything plays mod8 (1080) properly -- because that's the HDTV standard.

Okay. Thanks, Jagabo.