HD Cropping questions

[NotSoEasy]

Forgive me if this is listed someplace on the site. I did my best to search for what I am looking for.
Converting HD (1920x1080) material to MKV keeping it either 1080 or 720

First off. Is there a chart or maybe someone can just write them down here, that tells you "crop numbers" for specific aspect ratios ?
What would you crop 1:85.1 and 2:35.1 to remove the letterbox lines when dealing with 1080

Second. Does it even matter ? Are those black lines even taking up that much in the end result ?

[aedipuss]

try vidcoder. it has a cropping function and a preview to see how it looks. letterboxed or cropped is up to you, but most prefer mkv cropped.

[jagabo]

1.85:1 video in a 1920x1080 frame: Crop a total of 42 lines off the top and bottom
2.35:1 video in a 1920x1080 frame: Crop a total of 263 lines off the top and bottom

But it's best to leave your height an integer multiple of 16, or at least 8. So leaving 1920x1040 or 1920x816 is better.

[NotSoEasy]

Should have mentioned that I use Handbrake for encoding.

Thanks or the numbers.
As to my second question though. Does that extra info in the black bars have any significant outcome if left uncropped ?

[jagabo]

Does that extra info in the black bars have any significant outcome if left uncropped ?

If it's noiseless black bars it will consume very very little bitrate. It this was something like a VHS recording, with lots of noise in the black bars, it would consume a more significant amount of bitrate.

[fritzi93]

That's why I've never bothered with cropping when I make an MKV. And it's still a compliant resolution if I were to for some reason want to run it through tsMuxer to make a Blu-ray or AVCHD from one.

So the majority do crop then? I just don't see the point when it's such an insignificant amount of space saved.

[NotSoEasy]

So what about dealing with "bugs" in that area ? Much bitrate in that case ?

[jagabo]

So the majority do crop then? I just don't see the point when it's such an insignificant amount of space saved.

There are times when it makes sense to crop. For example, when you have a ~16:9 movie letterboxed on a 4:3 DVD. When you watch that video on a 16:9 TV you end up with a small picture surrounded by letterbox and pillarbox bars. If you crop away the black borders you won't have that problem.

[jagabo]

So what about dealing with "bugs" in that area ? Much bitrate in that case ?

It depends on how much noise is in those black borders. If there's a lot of noise it will eat a lot of bitrate.

[fritzi93]

I should have been more specific. I was talking about MKVs made from Blu-Ray. I confess I don't watch DVDs much any more. Although when an old favorite is released on Blu-Ray, I buy it.

Yeah, the postage stamp thing, like on some early DVD releases, for example Home Alone. DVDRB could easily take care of that, if you wanted to output as DVD-Video.

[jagabo]

I should have been more specific. I was talking about MKVs made from Blu-Ray.

You may run into the same problem with Blu-ray rips in the future. What if 21:9 TVs become the norm? All your 2.35:1 Blu-ray rips will play with both letterbox and pillarbox bars if you don't remove the black borders.

[NotSoEasy]

I guess then in some cases it would want to be done but in most cases when all you have are black bars.
Best to just leave them be as they do no harm on output.