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Is this only with flac? How far does it get out of sync?
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It has gone out of sync with about a second or second-and-half before I've either paused/resumed the stream or restarted it.
I wanted to do a more extensive test yesterday (sorry for the late reply), but got sidetracked when I installed (and subsequently had to revert) the most recent Intellinux drivers (libva*1.3.1, libdrm*2.4.54 & xf86-video-intel-2.99.911) as they broke multi-monitor support (all that compile work+.deb packaging for nothing!)
But anyway, I did test a Dolby Digital Stream, which was ok, and also a DTS stream, which also appeared ok.
I will most likely be able to do a more complete test today (i.e, watching an entire movie) to make sure. The FLAC issue obviously came as a result of me watching a whole feature (and comparing a second MKV with a FLAC track), but it was however quite noticeable early on (within 5 minutes)
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I verified this again last night to rule out issues with audio across the board, but so far the issue (only) affects FLAC streams. I watched a whole feature with a DTS soundtrack and no audio sync issues were detected.
btw.–the video appears to be slightly more fluid than previous versions (or maybe that is just me?) I detected one dropped frame in about 30 minutes runtime.
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Thanks for those infos. Those are helpful to track this down. FLAC audio frames are quite long in duration. This gives me an idea where to look at.
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No problem. Let me know when there are things to test and I'll check out the git source tree again and recompile.
I hope to be able to test a Dolby TrueHD stream as well, just to rule out any issue with transcoding audio in general (since it is handled, from the receiver point of view, the same way as a FLAC stream in that it is processed into Dolby Digital 640 kbit/s for S/PDIF output), whereas DTS HD MA obviously is more compatible in that it extracts the DTS Core.
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fritsch
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Wait. You talk about transcoding, right? Multichannel flac transcoded to Dolby and output as AC3?
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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2014-06-05, 13:32
(This post was last modified: 2014-06-05, 13:32 by Drag0nFly.)
Correct. FLAC streams would have to go through this process for any receiver (since none, AFAIK, support it directly), but Dolby TrueHD streams could theoretically be treated differently which is why I wanted to rule that out. I have only a few films with TrueHD on the media server so haven't been able to test this as yet.
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fritsch
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2014-06-05, 16:04
(This post was last modified: 2014-06-05, 16:05 by fritsch.)
Flac is normally decoded and output via LPCM. So the transcoding path you use is something special. For TrueHD I think we also don't get the Core, but rather decode and encode (in spdif +ac3 transcoding case) - but did not look into that bit stuff for longer.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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Yes, S/PDIF (optical/coaxial) does not as we all know support 5.1 output over LPCM (even though it has more than enough bandwidth to do so), so it has to be re-encoded into DD 640 kbps. However, the material I tested on actually only had either a mono track or a stereo track, so I suspect the standard path was indeed used. I also tried the option to recode the mono track into two-channels, but it behaved the same.
And it is right that TrueHD has to be re-encoded to be output on S/PDIF (i.e, does not contain a core stream as DTS HD MA does, which is one of the reasons it became the 'standard', since non-HD audio devices only had to support one stream instead of two.)
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As stated before, I cannot test mainline as it does not support multi-head. I have limited time to run XBMC tests, so they are being run on my main XBMC rig.
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fritsch
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what? All the X11 changes were merged into mainline.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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That is news to me. I've asked about this on several occasions; the last time about a month ago where it was stated that mainline still relied on SDL.
If the work from FernetMenta's branch has been merged in since then I can re-test this when I recompile a new XBMC version.