Need additional info about re-encoding Blu-Ray

[snipingkid]

Hi,

I just built a Home Theater PC to be able to manage all of my movies and would like to have more information about encoding blu-ray to reduce storage usage. I understand that you cannot keep quality whilst reducing a file's size, but I would like to find a good ratio.

I have a pretty decent setup, and would not like the investments to come to waste. I would like to establish a standard in the way I encode the movies in the HTPC.

I am currently using RipBot264 to encode the movies. Am I using a good application? What do you guys recommend before I rip the whole collection? How small can a single blu-ray movie become without losing too much quality)? Thanks for any tips and recommendations.

Regards,
Patrick

[poisondeathray]

Quality is subjective. What might be "good enough" for one person might not be for another person

Also each movie is different. Some movies will require much more bitrate (therefore size) to look "normal". e.g. movies with a lot of noise like 300 compared to a smooth cartoon movie.

If you are using an HTPC, you don't need VBV buffer for device compliance, so you can get away using 1pass CRF mode, which is faster and tends to give you a "constant quality" result. Just pick the crf value that is good enough for you (lower is higher quality, bigger filesize , most people use 18-22, if you want to reduce the size, I would stick to 22). Beware, however, the filesize may vary dramatically depending on the source. e.g. a noisy movie with a lot of action might be many times larger than one that doesn't. So if you need a specific size, you have to use 2pass.

Bottom line: you have to experiment to see what is "good enough" for you on your setup.

[snipingkid]

Thanks for your response poisondeathray.

I have another question regarding movie size (blu-ray). Assuming every blu-ray movie is ~50gb, on average, how small/big do you think each film will be taking?

At MOST 20gb and at LEAST 4GB? I'm talking about the movie alone, I will not be keeping menus. (Am I shooting at the sky with this... or?)

Do you think I'd be better off ripping the content I don't need and keeping to the manufactured HD?


Sorry for the numerous questions. I am encoding one as we speak.

Thanks for the help.

[poisondeathray]

You're not going to like this reply but the truth is : No one can answer those questions

It depends on the content (type of movie) and the quality you are willing to accept.

For example, if you used crf 18, it's sometimes bigger than the original(!) on some content, but smaller on others. If you are fixated with "x" amount of space, you have to use 2pass mode, but some movies might look bad and you might be "wasting" bitrate on others if you choose an arbitrary number. I think most people in your shoes would use crf22 as "their default setting". Some movies might be 10GB, some might be 20GB etc... it completely depends on the content

Honestly, I don't think it's worth re-encoding. HD space is cheaper almost every month, and it takes a good few hours to encode, many more or even days on an older pc.

[snipingkid]

After "trying" to encode my first blu-ray, I come to the conclusion that I will need to modify many additional settings and probably head for quad-core, which is what I should have gotten in the first place.

I'll see how much I can pull off by doing a standard rip (deleting menus, additional footage, unused subtitles, sound channels and more).

I'll keep you posted on how much I've managed to take out. I now need to figure what video format I'm going to use as a whole. ^^



Thanks for your tips.

[me-eyes]

I agree with poisondeathray - you need to look at cost benefits of time spent re-encoding and the amount of space the movie will take up. If it takes hours to do this each time and you save maybe half the space on the BR disc, you might be as well just ripping it to an iso file. Much quicker, you keep all the menus & extras, and with the cost of HDD coming down all the time the space taken isn't that much.

[snipingkid]

That's exactly what I've been calculating.

However, even if the cost of Hard Disk Drives is low (and getting lower), I still need an efficient solution.

Here are the stats
1 Blu-Ray Film = 50GB (ISO).
1TB of Storage (roughly 930gb)= $135 CND (assuming I get reliable HDDs).
Film per Drive : 18 (18.6)
Cost per film : $7.25

As you can see, keeping the ISO is NOT an efficient solution. I could go with cheaper drives (ex: 1.5TB seagate for $135; but these have higher failure rates, and this is my backup solution). Even then, I would get a cost per film of $4.8 (which is good, but I'd be risking time if a drive happens to fail).

I will try ripping a blu-ray tonight to see how much I can pull off by taking out unnecessary content. I'll post my result ASAP.

[poisondeathray]

I don't keep the ISO, I just keep the main track and main audio. Ditch the 20 or so other tracks, languages, menus, subs, extras and you will save a lot of space