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phenixdragon
Aug 10, 2010, 08:37 PM
I started using Handbrake this week to convert my Blu-rays over to smaller files to use to stream over my home network. However, I have been noticing an issue when it seems like the file becomes too large. I am using just some basic settings with Handbrake, keep the files as 1080p.

An example of the problem I am having is with Batman Begins. When I set it to use constant bit rate at 70%, it create a 10 gig file. When I try to add it to iTunes it fails. When I try to play it with VLC, nothing happen. However, when I set Handbrake to 60%, file works fine.

So is there some type of limit that MP4 movie files can be? I am also running OS X so maybe it's an OS X issue?



aarond12
Aug 11, 2010, 09:30 AM
I believe iTunes has a upper limit of 4GB on its MP4 files. Correct me if I'm wrong, but I seem to remember a "larger than 4GB for AppleTV" checkbox in Handbrake or some other application.

I just searched through the M4V files in my iTunes library, and nothing -- including movies -- is over 4GB. I keep the bigger movies on a NAS for playing to my PS3 or my WDTV HD Live box.

Mac OS X has no problems with files over 4GB, even movies. I think this is an arbitrary limit in iTunes. (4GB = 32 bits of data)

-Aaron-

phenixdragon
Aug 11, 2010, 09:41 AM
I could try the checkbox but I have had a couple of movies larger then 4 gigs but less then 5 work. I really don't care if it works in iTunes but I noticed that VLC also won't play the file. However, if I do AC3 passthrough and all the other settings the same, it plays but with no sound since my Mac can't decode AC3.

phenixdragon
Aug 11, 2010, 09:42 AM
Wow, I take that back. THe AC3 version even with the same settings is only 2.62 gigs while the 6 channel one I created was about 12 gigs. Hm...

roidy
Aug 11, 2010, 09:50 AM
iTunes has no limit on the size of a file as long as you check the "Large file size" checkbox in Handbrake.

Also if you're seeing a percentage value in Handbrake for the constant quality value then you're using an older version of Handbrake. Download the latest nightly version it's much better, in the new nightly versions I use a CQ RF value of about 19-18 for Blu-ray and 20-19 for DVD.

phenixdragon
Aug 11, 2010, 09:54 AM
Running version 0.9.4 for OS X. Looks to be the latest version. Does list the RF value which I hadn't noticed. Just it also lists the percentage too.

phenixdragon
Aug 11, 2010, 09:58 AM
I'm going to do some more testing because when I had AC3 passthrough I swear the video settings were the same as when I tried 6 channel, yet the 6 channel was about 10 gigs larger. Maybe I made a mistake with the AC3 but I will also try the large file and see what happens.

roidy
Aug 11, 2010, 10:30 AM
Running version 0.9.4 for OS X. Looks to be the latest version. Does list the RF value which I hadn't noticed. Just it also lists the percentage too.

Yep, 0.9.4 was the last stable version but it's quite old now. Try one of the nightly's from here:-

https://build.handbrake.fr/

I'm going to do some more testing because when I had AC3 passthrough I swear the video settings were the same as when I tried 6 channel, yet the 6 channel was about 10 gigs larger. Maybe I made a mistake with the AC3 but I will also try the large file and see what happens.

I think thats because AC3 is a compressed format and 6 channel is uncompressed, thus much much larger.

dynaflash
Aug 11, 2010, 10:52 AM
First 70% cq is waaay too high imho for a blue ray source. Also yes 0.9.4 showed both percentage as well as rf as we were weaning people off of the misleading % scale that hb had always used for constant quality.

AC3 in HandBrake is passed through so whatever the source bitrate is is what you'll get. 6 channel discrete is six channels of aac compressed from the ac3 source. My guess is neither is the reason the file size ballooned. My guess would be that it was a cq encode using a very high quality setting ... which can balloon size especially from blu ray given that 70%. Go with what roidy said and see if its any better (should be).

On the large file size checkbox: Has nothing to do with a playback platform issue, has to do with the fact that a 32 bit mp4 cannot exceed 4GB. So HB has to be told to mux the mp4 as a 64 bit mp4 ... which in general has no size constraints. Most mac devices (including atv and any recent ipod with video capabilites) as well as the mac itself has no issues with 64 bit mp4s.

phenixdragon
Aug 11, 2010, 11:33 AM
I think thats because AC3 is a compressed format and 6 channel is uncompressed, thus much much larger.

Yes but AC3 shouldn't add over 8 gigs to the file, maybe a gig. But I had thought going 6 channel is using even less space then AC3. I tried using Doble TrueHD and it was smaller then Dolby Digital.I may just stick with AC3 though.

phenixdragon
Aug 11, 2010, 11:37 AM
First 70% cq is waaay too high imho for a blue ray source. Also yes 0.9.4 showed both percentage as well as rf as we were weaning people off of the misleading % scale that hb had always used for constant quality.

AC3 in HandBrake is passed through so whatever the source bitrate is is what you'll get. 6 channel discrete is six channels of aac compressed from the ac3 source. My guess is neither is the reason the file size ballooned. My guess would be that it was a cq encode using a very high quality setting ... which can balloon size especially from blu ray given that 70%. Go with what roidy said and see if its any better (should be).

On the large file size checkbox: Has nothing to do with a playback platform issue, has to do with the fact that a 32 bit mp4 cannot exceed 4GB. So HB has to be told to mux the mp4 as a 64 bit mp4 ... which in general has no size constraints. Most mac devices (including atv and any recent ipod with video capabilites) as well as the mac itself has no issues with 64 bit mp4s.

Well when I do AC3 pass thru at 70% the the file was under 3 gigs. But I can say that anything less then 70% I can see a difference in quality. But I will try that other build and see what happens.

dynaflash
Aug 11, 2010, 12:10 PM
Well , you are recompressing the source so there will always be some quality loss. Its is unavoidable and certain.