High-Profile preset for iPad and Apple TV 2

[ProXy]

I am quite new to Handbrake and use it to convert some DVDs to m4v files using the universal preset. This seems to work fine on the iPad and also on my Apple TV 2. Should I use the High-Profile preset to increase the quality of my videos or is the universal one good enough for DVD quality?
When using the High-Profile preset, are there some issues watching the videos on specific devices?

Thanks in advance,
Stefan

[Deleted User 11865]

Perhaps a more obvious solution would be to use the iPad or AppleTV 2 presets?

[ProXy]

Lol, you are right I am just not sure if using the high profile preset would work fine and provide a better quality compared to the device specific presets. There are so many options that I am not sure, what really changes the quality of the encoded file..

[TedJ]

As long as you're encoding DVD sources only, the High Profile h should work fine on the iPad and ATV2. If you're planning on encoding HD sources, either Blu-ray or HDTV recordings, then the Apple TV 2 preset provides some limiting on frame size and frame rate to ensure playback.

In this case, the choice of preset won't have a major effect on quality, that's largely defined by the RF value selected... what will change is the encode time and the bitrate required to reach that quality level. That is, slower encodes and smaller files.

Moving to Devices.

[nehalem]

Hmm. I didn't know an ATV 2 preset existed so I just modified the HP to lower res to 720p for all HD sources. It's worked without flaw so far, and I've converted a lot of my blu rays (probably about 50). So either I've been lucky of the framerate issue isn't very common.

[TedJ]

uThe vast majority of Blu-ray titles are 23.98 fps and won't present a problem. You're more likely to have problems with HDTV sources.

[bitslinger]

There's only a few differences between iPad, AppleTV2 and High Profile. I was curious what the tradeoffs were. It may be elsewhere in the forums, but here's the differences, hopefully it may save someone else's time from parsing the preset command lines and figuring it out! (This is based on default presets as of HB 0.9.5)


iPad, AppleTV2, and High Profile ALL SHARE this:
./HandBrakeCLI -i DVD -o ~/Movies/movie.mp4 -e x264 -q 20.0 -f mp4 --loose-anamorphic -m
Mostly self-explanatory (-q sets video quality, -m adds chapter markers)

iPad and AppleTV2 BOTH have:
-r 29.97 --pfr -4
This limits framerate to 29.97 or lower (PFR=peak-limited frame rate). The -4 (or --large-file) allows >4 GB files (which breaks compatibility with most players). High Profile does not set these options.

-X 1024 (iPad)
-X 1280 (AppleTV2):
This sets max width of the video. High Profile is unrestricted, and defaults to the same width as the input video.

These are iPad's audio settings (for Dolby Pro Logic II 2 ch, AAC 160kbit, no DRC) :
-a 1
-E faac
-B 160
-6 dpl2
-R Auto
-D 0.0

While AppleTV2 and High Profile BOTH just add the AC3 surround as track 2:
-a 1,1
-E faac,copy:ac3
-B 160,160
-6 dpl2,auto
-R Auto,Auto
-D 0.0,0.0

There's no harm using the latter settings with the iPad preset, other than larger file size.


Finally, High Profile ONLY has these:
--detelecine
--decomb
-x b-adapt=2:rc-lookahead=50

Detelecine and Decomb seem like useful options to use with iPad and Apple TV 2 as well... Any good reasons NOT to use them?

The -x passes custom options to the x264 encoder. This involves B-Frames and Rate Control Lookahead. The x264 defaults (for iPad and AppleTV2 presets) are:
-x b-adapt=1:rc-lookahead=40

I assume they're removed to optimize the speed/quality tradeoff for the lower-res encodings. Maybe someone else could chime in on that?

http://mewiki.project357.com/wiki/X264_Settings#bframes
http://mewiki.project357.com/wiki/X264_ ... -lookahead

The older AppleTV preset differs from AppleTV2 by max width and the custom X264 options:
-X 960
-x cabac=0:ref=2:me=umh:b-pyramid=none:b-adapt=2:weightb=0:trellis=0:weightp=0:vbv-maxrate=9500:vbv-bufsize=9500


FWIW, HTH....

[Deleted User 11865]

iPad and AppleTV2 BOTH have:
-r 29.97 --pfr -4
This limits framerate to 29.97 or lower (PFR=peak-limited frame rate).

Correct. This means "Same as source, unless the source framerate exceeds 29.97 fps".

The -4 (or --large-file) allows >4 GB files (which breaks compatibility with most players).

The tooltip is outdated. Large file size breaks compatibility with some players (not sure which, TBH).
The PS3 used to not support it but current firmwares have no problem with it.

Detelecine and Decomb seem like useful options to use with iPad and Apple TV 2 as well... Any good reasons NOT to use them?

They're disabled by default because they cause a minor speed hit.
They're in the High Profile preset for historical reasons (that preset replaces several presets, including the Television preset which had them enabled).
They're usually unnecessary for HD-DVD and Blu-Ray Hollywood films, but enabling them for DVDs and TV recordings is a good idea.

The -x passes custom options to the x264 encoder. This involves B-Frames and Rate Control Lookahead. The x264 defaults (for iPad and AppleTV2 presets) are:
-x b-adapt=1:rc-lookahead=40

I assume they're removed to optimize the speed/quality tradeoff for the lower-res encodings. Maybe someone else could chime in on that?

jbrjake made the iPad preset that way; the AppleTV 2 preset is based on the iPad preset. As far as I know, the idea behind is to have a preset that uses the default x264 settings (which are considered a good speed vs. compression efficiency tradeoff by the x264 developers).

The older AppleTV preset differs from AppleTV2 by max width and the custom X264 options:
-X 960
-x cabac=0:ref=2:me=umh:b-pyramid=none:b-adapt=2:weightb=0:trellis=0:weightp=0:vbv-maxrate=9500:vbv-bufsize=9500

For compatibility reasons. The AppleTV 1 doesn't support 720p30 (1280x720@30fps), so the resolution defaults to 960x544.
It can be bumped to 720p manually if the source framerate is less than or equal to 25 fps.

The advanced options are meant to work around the original AppleTV's lack of support for many H.264 features.
The vbv settings are meant to ensure smooth playback of 720p content by the AppleTV.