[6corewhore]

1st, I know aTV 2 only passes 720P from a 1080P source...

Setup Det's:
Running the latest aTV 2 iOS (4.2.2/4.3), used Seas0nPass, installed NitoTV, all necessary add-ons, etc. Ran the install for the latest XBMC nightly w/ seatbelt/blocked hosts/autoupdates off, etc. Have my aTV 2 connected via ethernet using SMB to a second "Time Capsule" to access my movies (mainly SD m4v's) on its HDD (drag and drop encoded rip's from my Mac Pro to the "Time Capsule's" HDD via Finder). Everything plays amazingly, AC3 sound on my Pioneer Elite VSX-33 outputs DTS in my mkv's and full, rich AC3 5.1/7.1 with this latest nightly (amazing how one m4v sounds so much better now). Also changed the Audio settings to 16-bit...

Issue:
I likely know what's happening just want to confirm it. I HB'ed BD "Pirates of the Caribbean: At World's End" into a 16GB mkv (took 18 hours on my 2010 3.33GHz 6-Core Mac Pro). The mkv plays perfectly through VLC on my Mac (OS X 10.6 and 10.7 - developer here), but stutters on the latest XBMC. ATV2 accepts 1080P then outputs to 720P, it has handled previous 1080P mkv's, however I have the sense this 16GB mkv is too much and I need to tweak my advanced HB settings as buffering issues, etc. seem to indicate file size is an issue (playing around with settings on my BD encodes, 16GB is overkill, testing quality/usability first). Studied on all the threads with this issue, followed all the recommended solutions for some. I disengaged subtitles, post-processing (which seemed to be the issue as if on it would crash instantly, when turned off it barely played). Also deleted unnecessary iPhone oriented Launchdemons from root/System/Library to free up memory (AddressBook, chud and others).

If this is just a matter of too large an mkv great, however if this is something else I'm all ears and I appreciate any help! Thanks guys!

[Memphiz]

Maybe the max bitrate of your mkv is to high? Mediainfo of the mkv may be helpful here ...

[6corewhore]

Maybe the max bitrate of your mkv is to high? Mediainfo of the mkv may be helpful here ...

Sorry bout that, more info would be helpful (and thanks for your input)

Image is from VLC playback (12389 and 10735 kbps are way too high, good call, shame it's perfect on my Mac Pro but aTV 2 can't handle it):



I encoded it in HB mkv using CQ at 19 (most likely too high, I've been using 18 for my SD encodes), and these advanced settings:

b-adapt=2:rc-lookahead=50:ref=8:bframes=8:me=umhubq=10:merange=32:analyse=all:trellis=2:direct=auto:psy-rd=1.0,0.15

Motion Est Range, Subpixel ME & Mode and bframes most likely too high for BD's. I use these settings for my SD encodes.

Goal: keep as much quality of the lossy DVD rips as possible to toss my DVD collection and go digital. Size/space of files aren't an issue, quality is paramount.

Setup: 3.33GHz 6-Core Mac Pro w/ 10GB RAM running virtual 12-Cores, can encode a SD w/ those settings in about an hour and get around a 2-3 GB m4v. Spent ~five months researching everything w/ HB variables, getting advice from the HB guys and forums. Only variables I've been questioning is Deblocking & Psychovisual-RD/Trellis, the differences in grain/sharpness are so slight it's difficult to get a solid setting. Otherwise audio track 1 is always stereo for iDevices, track 2 AC3 5.1 Passthru or DTS, and other tracks for extra's.

As for the BD mkv encode, definitely need to lower my settings.

[davilla]

Sorry bout that, more info would be helpful (and thanks for your input)

Image is from VLC playback (12389 and 10735 kbps are way too high, good call, shame it's perfect on my Mac Pro but aTV 2 can't handle it):



I encoded it in HB mkv using CQ at 19 (most likely too high, I've been using 18 for my SD encodes), and these advanced settings:



Motion Est Range, Subpixel ME & Mode and bframes most likely too high for BD's. I use these settings for my SD encodes.

Goal: keep as much quality of the lossy DVD rips as possible to toss my DVD collection and go digital. Size/space of files aren't an issue, quality is paramount.

Setup: 3.33GHz 6-Core Mac Pro w/ 10GB RAM running virtual 12-Cores, can encode a SD w/ those settings in about an hour and get around a 2-3 GB m4v. Spent ~five months researching everything w/ HB variables, getting advice from the HB guys and forums. Only variables I've been questioning is Deblocking & Psychovisual-RD/Trellis, the differences in grain/sharpness are so slight it's difficult to get a solid setting. Otherwise audio track 1 is always stereo for iDevices, track 2 AC3 5.1 Passthru or DTS, and other tracks for extra's.

As for the BD mkv encode, definitely need to lower my settings.

"ref=8:bframes=8", hehe, non-standard h264 encoding. when will people learn to stick with the standards that are there rather than diddling about with setting that they have no clue about. Hardware decoders are very picky about following the standards. Step outside them and then you get crappy playback.

[6corewhore]

"ref=8:bframes=8", hehe, non-standard h264 encoding. when will people learn to stick with the standards that are there rather than diddling about with setting that they have no clue about. Hardware decoders are very picky about following the standards. Step outside them and then you get crappy playback.

WHOOPS. Non-standard, meaning not-compatible or simply unnecessary? I used those I read higher ref frames=better compression and Analysis settings such as Adaptive B-Frames required those settings, no? These settings have been fine with my SD m4v's. Sorry mate, this is all new hat to me and I've been studying me arse off on all of it. What should I do with those settings? (and thanks for EVERYTHING, loving XBMC w/ iOS 4.3 and nightly build, HUGE diff in audio, I've made a few donations to help out).

[davilla]

research h264 profiles. such as [email protected], these mean a very specific group of setting.

A very good example of an silly encoded file is the well known killa sample. 16 reference frames

[6corewhore]

research h264 profiles. such as [email protected], these mean a very specific group of setting.

A very good example of an silly encoded file is the well known killa sample. 16 reference frames

Thanks! I did quite a bit of research through HB forum/guide and a few others. Studied differences bet mkv and m4v containers using H.264 (x264) Codec, video settings such as FPS/VBR and CQ settings of around 22-18 depending on source. Audio tracks are easy; stereo track first for iDevices, then AC3 Passthru or DTS for track 2 and 3+ for director's commentaries, etc. I spent months researching Advanced Settings such as Psycho-visual rd/Trellis and Deblocking to determine effects on grain and sharpness. From what I read and a lot of the advice on forums I tweaked Analysis a bit for optimal quality and compression, and kept Encoding frames around 5-8, etc. and made certain that required Encoding settings were in effect for certain Analysis settings. Don't want to use presets as I want to get as much quality as possible, so I have saved about 20 presets from experiments. Encoding 1080 mkv's should be fine as the aTV handles 1080 and encodes to 720, so if Apple (or some such company) produces a device with full 1080 support I should (in theory) be future proof.

I'll take a look at [email protected], etc tonight after I finish one of my many projects (building a desk, still need to hone and finish the cherry wood top). Fun!

...and 16 ref frames, that's a bit much

Thanks again!

[6corewhore]

So Apple TV 2's A4 can't handle anything above 3.1?

I have been able to get a full 1920x1080 mkv with high settings to play via SMB ethernet from an attached HDD, however I have to disengage the hardware acceleration (videotoolbox) in order for the movie not to crash, and yet it stutters trying to buffer over the direct ethernet SMB connection. Meaning my bitrate must be too high.

I've read on recommended settings for h.264 BD encodes and others have had no issue. Perhaps 1920x900 or 800 (anamorphic loose) and CQ around 20-22 is better? I've encoded three mkv's with the same movie, got it down to 9 GB's but I fear lower settings will degrade quality should I chose to use another media device that can handle full 1080P.

Also, with regard to mkv BD audio, when choosing the track for BD audio I only have the option for AC3 5.1 6-Channel discrete 640 kbps. Is this accurate?

[davilla]

So Apple TV 2's A4 can't handle anything above 3.1?

No, atv2's videotoolbox can handle up [email protected] and even L5.1. Apples dirty little secret.

H.264 video must comply with the L5.1, L4.1 and L3.1 limitations for the Decoded Picture Buffer (DPB) size, which limits the video resolution and number of reference frames. From what I read, Level 4.1 H.264 allows 9 reference frames for 720p and 4 reference frames for 1080p. Exceed that and your h264 is out of spec.

[6corewhore]

No, atv2's videotoolbox can handle up [email protected] and even L5.1. Apples dirty little secret.

H.264 video must comply with the L5.1, L4.1 and L3.1 limitations for the Decoded Picture Buffer (DPB) size, which limits the video resolution and number of reference frames. From what I read, Level 4.1 H.264 allows 9 reference frames for 720p and 4 reference frames for 1080p. Exceed that and your h264 is out of spec.

You are awesome and hit my problems right on the head. Now I know exactly what I need to do from here on. Thank you again for all your help