600MB HD Movies

alexlyons

Ok first off I don't condone illegal downloading or any form of piracy at all, so no comments to that affect please.


I have seen files, and watched the actual movies from these files, that are roughly around 600-700MB in size and are 720p movies. Roughly 2 hours in length and are in mkv format.

I backup my own blu ray collection on my Mac's and would love someone to explain how, and using what program on a mac, I can get 720p movies at this size, as it is technically possible.

The files are almost always x264, but handbrake has some form of x264 option but for the life of me i can't get 720p at that size. Maybe I need a different program or other advice.

Any help appreciated!!

AlmightyCushion

I haven't seen any 720p files less than a couple of gigs. It's possible they striped out some of the audio channels to make it 2.1 audio. That should save some space. They could also be sacrificing quality for file size. What is the quality like compared to your own backups?

alexlyons

for 700mb its incredible!! it's not 1080p, and i have 5.1 speakers but not setup right on the mac, so it may not be for everyone, but for the size its great quality.

How would I check the sound?

alexlyons

just checked with handbrake and it's giving me 2 channel stereo at 160kbps.

obviously its not 5.1, but what would the bit rate be on full blu ray normally?

AlmightyCushion

alexlyons wrote: »

just checked with handbrake and it's giving me 2 channel stereo at 160kbps.

obviously its not 5.1, but what would the bit rate be on full blu ray normally?

Don't know what the bit rate of bluray is but it's a lot higher than 160Kbps. Still, if you're happy with the quality what does it matter.

alexlyons

my thoughts exactly.

started an encode with those audio settings from a blu ray disc, worked it out with what its done so far it will give me a 4.5GB mp4 or there abouts.
That's at 1080p, but any idea on what to change in handbrake to get that smaller?
it's using H.264 (x264) and at constant quality of RF:20

I'm guessing the advanced tab might help but haven't a clue!

Voodu Child

I have seen people encode 720p movies at sizes of 700MB (and smaller!), but to be honest this would be considered completely stupid in the encoding community. If you think they look good you need your eyes checked (no offence :pac:)

Its counter-productive. Even with H264 high-profile, the bitrates you'll get from a 700MB encode (assuming its a typical length movie) are way too low for a 720p frame size, you'll get horrible artifacts and the end-result will look much worse than a 700MB encode at standard defintion.

And you mention backing up your Bluray, so this is a ridiculous thing to do. If a Bluray gets scratched you'll be left with a horrible, crappy looking shadow of the original thing.

If you really want to go ahead with it, most encoders use megui. These guys using stupidly low bitrates will be denoising the crap out of their source (basically blurring it to make it less complex), using custom filters and pushing the x264 settings as high as they go. To save as much bitrate for the video, they normally use very low bitrate audio (~60kbps stereo), and that means AAC HE with SBR and maybe PS. It'll sound like crap.

AlmightyCushion

alexlyons wrote: »

my thoughts exactly.

started an encode with those audio settings from a blu ray disc, worked it out with what its done so far it will give me a 4.5GB mp4 or there abouts.
That's at 1080p, but any idea on what to change in handbrake to get that smaller?
it's using H.264 (x264) and at constant quality of RF:20

I'm guessing the advanced tab might help but haven't a clue!

No idea unfortunately.

alexlyons

Voodu Child wrote: »

I have seen people encode 720p movies at sizes of 700MB (and smaller!), but to be honest this would be considered completely stupid in the encoding community. If you think they look good you need your eyes checked (no offence :pac:)

Its counter-productive. Even with H264 high-profile, the bitrates you'll get from a 700MB encode (assuming its a typical length movie) are way too low for a 720p frame size, you'll get horrible artifacts and the end-result will look much worse than a 700MB encode at standard defintion.

And you mention backing up your Bluray, so this is a ridiculous thing to do. If a Bluray gets scratched you'll be left with a horrible, crappy looking shadow of the original thing.

If you really want to go ahead with it, most encoders use megui. These guys using stupidly low bitrates will be denoising the crap out of their source (basically blurring it to make it less complex), using custom filters and pushing the x264 settings as high as they go. To save as much bitrate for the video, they normally use very low bitrate audio (~60kbps stereo), and that means AAC HE with SBR and maybe PS. It'll sound like crap.

completely understand where you're coming from as I'm one for quality as high as it can go in most cases. Yes, there is no point in backing up blu ray to crap files, but these files that I've seen aren't crap at all, no artifacts, no blurring (photographer so I understand de-noising!), yes the audio might not be surround but it's not a big deal. When I get more HD space I'll re encode them from the disc.
It's extremely handy for bringing a good few of my backed up movies on the laptop if they are decent 720p and small sizes. as i said, the audio isn't a big issue in that regard, of course it would be for full quality backups when I have the space.

softdancomputer

its possible, not easy, and yes the result can be very good. Use avisynth, nero audio codec and Megui. Google, you may find some tutorials.

alexlyons

cheers, i'll look into those programs and do a bit more googling

Khannie

For a 2 hour movie to come in at 700MB and still looking reasonable you're maybe looking at a 720p source, but it's going to look bad (even with x264 settings that are optimised for quality) encoded at 1280x720. There's a "sweet spot" for resolution v's file size and 1280x720 at 700MB aint it. You could encode at DVD resoultion, with low bitrate sound (which you probably wouldn't notice) and hit the 700MB file size with x264 and still have it look very good though.

If you want to reduce movies you have to 700MB, handbrake should be able to do it. When you're encoding to that small a file size though you should make sure you're doing a 2 pass encode as it will noticeably improve the final result (the first pass looks at each frame so you can reasonably determine which ones can be heavily compressed and which ones need more bits to look good on the second pass).

To achieve a decent looking movie, I'd suggest these x264 settings: 2 pass encode, Cabac on, bframes on, bframes=3 or higher, framref=5, subq=5. Note that not all kit can decode x264 videos with bframes, but adding them will definitely improve visual quality (if you're playing back with a computer you should use them for example). You can learn more about the various quality versus speed options here. That page is aimed at mencoder, but those options more or less translate exactly for handbrake.

alexlyons

really appreciate that Khannie. Settings like that are very helpful!

I've uploaded a screen grab, its a 1920x1080 screen, the file is 1264x512 and 734MB.
sorry it took so long to get, didn't have a file to show initially.

In my eyes that's pretty amazing quality for that size.

I understand the major difference between 720p source and actually being 720p. Yes its a little bit off on the height, but its pretty close. So it's not dvd quality at that size, which is easy!

It'll be played on my Mac so I'll try those settings.

Voodu Child

Just some constructive criticism - that looks absolutely dreadful. Your bitrate is far too low for a 720p encode.

This is the same shot on a good (but not great) 720p encode
.

Yours looks very, very bad compared to what is already just a 'good' encode. Imagine how bad it looks compared to the Bluray source :pac:

Its completely blurred over, theres no detail, Gleeson has no facial hair, you havent preserved any of the film grain, his eyes are blocky, there's banding and artifacts all over the shop. And this is from what is a very compressible scene in the movie, a static shot with very little movement. I'd dread to think what your encode looks like later on in the film when it is dark and grainy.

Again, im not being smart, you asked for advice so this is constructive criticism.

If you want to do a 700MB encode that looks good, then you're going to have to use a much lower resolution. H264 is a very good codec but it can only do so much.

alexlyons

Fair play, I take that criticism. Compared to that it is sh*te I agree.

It's weird though, I'm used to 1080p for a good load of movies, but almost all are DVD's. I've never compared one against the other scene for scene like that.

Lets end this on a simple note.

I just ordered a 1TB drive to keep me going at minimum full quality 720p

Khannie

Really good post from Voodu there.

I would say, in general, that for a stereo audio encode at 160bps, you should be seeing file sizes around the 2-3GB mark for any kind of decent quality for a movie that is x264 encoded. Add a gig to that if you're preserving the 5.1 sound. If you want anything approaching the original source quality you're looking at 4GB or more.

If you're unsure about what bitrate to go for, single pass quantizer encodes are worth considering. A qp=19 will get you a very nice picture. For the same file size a 2 pass encode will result in better quality or a smaller file (take your pick...you could have the same quality with a larger file for example), but the single pass encode will be much, much faster. I generally stick with single pass encodes myself these days.

Voodu Child

Agree with the above, but the only thing i'd say is that for a single-pass quality-targetting encode using x264 you should be using CRF and not CQ.

Khannie

Gah! That's what I meant (and use). Oopsie.