Query about bitrate and bluray terms?

Kaiju

Kaiju

Kaiju

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So far I i've seen 1080p rips at 10mb-16mb and 720 rips from 4-8mb. Does that mean if you rip a bluray disc and set the bitrate around 4mb, it'll be classified as 720p and a bitrate of 10mb+ will be 1080p?

Am I right in saying 1920x1080 is 1080p and 1280x720 is 720p?

If for example I had a bluray rip at 16mb (opposed to trueHD @ 30mb+) and then re-encoded it to 4mb, would it be classified as 720p?

Basically are 1080p and 720p just advertising terms?

Lastly, for anyone experienced in the field, I want to change the resolution of a bluray rip I made from 1920x800 to 1920x1080, effectively stretching it (yes, i know). Would I have to transcode it again or is there a faster method/shortcut of doing this? Currently it takes me around 12 hours to transcode the file using a program called Mediacoder.

I want to change the subtitles characteristics too as they are too big in the current mkv container. Mediacoder only allows you to hardcode the subtitles into the video. Is there another way to edit the current subs in the mkv container? Hardcoding subs effectively makes it impossible to switch the subtitles off in the future.
 
The terms 1080P and 720P describe the resolution and aren't related to bit rate (except for the fact that at the same level of compression a 1080p will be bigger than a 720p film).

A 1080p film at 16mb would be the same resolution as a 1080p film at 4mb, just that the latter would be more compressed. Choosing a lower bitrate will not mean a change in resolution.

You're right about 1920x1080 being 1080p (or TrueHD) and 1280x720 being 720p.
 
Yeah, it clicked this morning. It's not about bitrate, it's about resolution.

Thanks for clarifying.

On that note, is it trail and error when ripping a bluray disc to get a bitrate best suited so it doesn't allow artifacts, blocking or stuttering?
 
I've found that in terms of quality the minimum to ideal file size for am average length movie should be around:

720p: 5GB - 9GB
1080p: 8GB - 15GB

Anything less and the characteristic signs of high compression become all too clear. Anything more and it's hardly noticeable and just a waste of space. What bitrate that works out as I'm not entirely sure, but you could work it out!

If you are re-encoding a mkv, there's no point in making the resulting bitrate more than the origional and no, there is no faster way of doing it. Unless... have you tried the zoom feature on your TV?
 
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Why would you want to stretch 800 to 1080? That will be quite a large stretch and will look terrible.
 
Kaiju said:
Lastly, for anyone experienced in the field, I want to change the resolution of a bluray rip I made from 1920x800 to 1920x1080, effectively stretching it (yes, i know). Would I have to transcode it again or is there a faster method/shortcut of doing this? Currently it takes me around 12 hours to transcode the file using a program called Mediacoder.

I want to change the subtitles characteristics too as they are too big in the current mkv container. Mediacoder only allows you to hardcode the subtitles into the video. Is there another way to edit the current subs in the mkv container? Hardcoding subs effectively makes it impossible to switch the subtitles off in the future.
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You want to handle both of these with your decoder - you shouldn't be re-encoding anything for what you're asking.

You can change the outputted size (it will look awful, but knock yourself out) with a scaling filter, such as found in FFDShow.

Soft subtitles' formatting (assuming 'too big' means too big a font) are also handled by the decoder. You'll have to check your player/decoder's settings to change this.
 
dbmzk1 - Thanks for the heads up.

I just re-encoded a 16000kb bitrate rip so I could rescale and change the font. Even though the bitrate is the same as the original, there is definitely a noticeable change in quality, at least up close.

There seems to be less grain on the screen, which i'm guessing is due to the fact that everytime you reencode something (instead of a lossless format), the quality will diminish.

kylew - On a 32" TV, the upscaling isn't as noticeable as my other 46" TV. Therefore, I prefer fullscreen on the 32".

Seft - Cheers bro, i'm only starting to figure this all out.

Last night I was playing with Mencoder (PS3 Media Server) and figured out how to change the subitles, AT LAST! I used some simple parameters to force the font change for the .ASS file. Mencoder also has a video upscaler option, so I changed the height and width parameters, but it didn't scale. That is my next challenge tonight! I will give FFDShow a whirl.

Thanks again guys, i'm stiill figuring out all the noob stuff.
 
Surely 1920x800 stretched to 1920x1080 is just giving you matchstick men and matchstick cats and dogs (lost aspect ratio with a 1 dimensional stretch), or do you chop the sides off and watch your movies cropped?... Letterbox for the win!
 
Kaiju said:
Thanks again guys, i'm stiill figuring out all the noob stuff.
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I don't want to sound condescending, but you're probably wasting your time attempting encoding without understanding how everything works. You'll likely just end up having to do everything again in a few months.

The lack of grain for example won't necessarily come with re-encoding (although you will lose some quality, even if it's imperceptible) but more with deadzone adjustments in the encoder.
 
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Corasik - It honestly doesn't feel like matchstick men when I watch it fullscreen. I've tried to adjust to letterbox for what, 10+ years now and it's like squinting unless, of course, I use my 46" TV.

Trouble is, my 32" TV is in my bedroom and I simply would like to watch it fullscreen on that sometimes. Again, I do not doubt letterbox is the way it should be watched, it's just my preference.

Seft - No, no, you are quite right, i've found that i've encoded, re-encoded and then re-encoded some more purely because I'm delving in with limited knowledge and don't know what options I have at my disposal. There has to be a learning curve though or how am I supposed to learn without hands on?

Thanks for the heads up about the grain. 300 loves the grain.
 
Dont forget the sound compression as well. If your backing up BD movies then they often come in a varity of sound formats such as Dobly Digital, Dobly Digial +, DTS,DTS-HD, TrueHD and etc.

If your just watching a movie on stereo speakers from your TV then getting Dodby Digital is good enough. A 90min film will be about 6-8GB at 1080 but if you throw in DTS or any of those HD sound then it can throw the movie into a larger filesize of 10GB.

Why do you think BD movies are about 40+GB? Its not just the extra content, you got the higher definition of sound and audio onto one disc. Something which DVD could never do.
 
Thanks Schizophonic.

I already had taken that into account as I only have a 2.1 Z-2300 set in my room. I simply use Nero's AAC Encoder @ 320kbps and it does the trick.

Again, this is all for my bedroom mind.
 
DTS and AC3 tracks aren't large at all and silly to encode them as you'll not have comparability with most hardware devices.

x264 encoding is worth learning, it takes a lot of effort to do a good job though.
 
I've found threads transferring DTS across an encoding, it seems like there is a workaround, so i'll give it a shot sometime.

I've given up re-encoding a rip for now, at least until i've got more knowledge on the subject.
 
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