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Nimiety

macrumors regular
Original poster
Sep 6, 2006
117
1
Hey y'all. Since many of us are intimately familiar with handbrake and converting of files, I wanted to pass on a problem I have to see if anyone else has replicated and resolved it.

In both cases, I'm using the standard handbrake appletv profile, so 2500 kb/s and adding a turbo'd 2-pass and manually selecting the audio track.

Converting regular SD material on Windows XP will go like this:
- start with an avi
- convert to video_ts with WinAVI
- convert with handbrake to m4v (mp4) for AppleTV

This process works like a charm on everything from tv shows through to multi-hour movies, and high bitrates and large file sizes, and everything looks great.

Converting 720p material on Windows XP will go like this:
- start with a mkv
- convert to video_ts with WinAVI
- convert with handbrake to m4v (mp4) for AppleTV

This process works, however, the first 5-10 minutes of video will appear choppy, after which it smooths out and looks perfect.

So, analysis: it's not bit rate, or frame rate, as neither would smooth out. I don't think it's load on the system, it's a core2duo 2.66 overclocked to 3.4 with a gig of ram - a regular movie can be converted in this process in about two hours including the 2nd pass. I suppose it could be a codec issue, but the files play fine locally before conversion.

Any guesses?
N....
 

frankiepdx

macrumors regular
Dec 28, 2007
133
0
Portland OR
Now this is just a guess but could it be network issues? Maybe it's finally done buffering when the stuttering stops.

I've noticed that on mine also (especially with 2 pass) but I also noticed an improvement since I updated with a new router from a clunker.
 

Nimiety

macrumors regular
Original poster
Sep 6, 2006
117
1
I don't think it's network - when selecting a movie, I can immediately FF 5-10 chapters ahead and it plays smoothly, but RW back to a very early point (say, chapter 2, maybe 2 minutes in) will exhibit the choppiness even if I RW several times to replay the same section of video again or after pausing to let the TV stream a bit more. Also, the choppiness is only evident in the video - the audio is perfect. If it were network latency, the audio would also studder. Finally, the behavior does not come out when watching any other movies that were standard def DVDs encoded with handbrake (with the same version of handbrake, of course).

It seems that this comes out in the encoding process, but other than posting in the HB forums I wanted to know if anyone here had run into the same thing before.
 
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