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[OverTheAir]

The background: I record TV using TS format so I can do simple conversion of MPEG video to more efficient H.264 at the same resolution and similar image quality.  It can save a lot of disk space on large TS files.  While I may give up some video quality in the process I can live with that ... and actually haven't noticed it. 

There are two issues though
1. If I use the MC converter (Tools > Advanced Tools > Convert Format) for this purpose it seems any 5.1 channel audio contained in my TS recordings in AC-3 form is converted to 2.0 channel AAC. I use the MP4 1080P conversion option. Does it do this for all conversion options?   Or am I doing something wrong that can be changed to prevent this?

2.  When I originally discovered this I reverted to using MCEBuddy to create an MKV file of the TV program that retains all audio channels and doesn't change from AC-3. This works fine except the sidecar file data created when MC did the original recording then has incorrect data in a number of areas.  I can mostly replace this data by appropriately renaming the file using TVDB references in order to automatically import whatever is in TVDB when MC imports the new file and creates a new sidecar file ... if the content is actually documented.  However the problem is that a number of program series I watch on PBS are never documented in online databases.

So it seems I either lose the surround sound using MC to convert ... or lose the metadata on a number of different programs ... or have to manually look up and/or transpose data from the old sidecar file into the new one which is not very practical.

Thoughts?  Suggestions?

[astromo]

A couple of thoughts (bearing in mind that I'm away from my home unit, so hopefully I don't give you a bum steer).

Firstly, how many audio streams are muxed with the .ts file? If there's also a 2ch stream, MC may be picking that up instead of the 5.1 when you initiate the convert process? You may have inadvertently triggered that stream. From memory, during playback do an on screen right click and check the playback audio stream from the context menu. MC should remember your selection.

Secondly, take a look at the pic and check out the convert format options. What do you get as far as audio is concerned? Can you sort out configuration to suit there?

[OverTheAir]

Thanks for the quick response.  Good idea but not the case here.  The original recording has three streams, the English 5.1 plus Spanish and French tracks which both show as mono using JRiver right-click method and independently using Mediainfo to analyze the file.  Btw, just to confirm what I'm hearing. The test file I am using, a TS recording of the US version of Antiques roadshow, plays back in 5.1 and the content on the back channels is what one might expect and different to the three front channels.  After I convert I just get left and right English channel information, I assume it is just the original channels and not mixed down but haven't been able to confirm that.

Ref your second suggestion. In the Convert Format drop down options (in MC20) there are only two mentions of audio and that's just to specify the use of MPEG2 audio per the attached image, I don't see any options for audio that specify channels, even if I select the Convert video to audio tick box.

[astromo]

The "Options" that I'm referring to is to the bottom right of the Convert button. When I navigate myself into the dialogue box connected to that link, there's a space for Audio but nothing there.

I'm with you on this one. Beyond me and one for the MC devs.

[RoderickGI]

As far as I have been able to determine, the Convert Format tool always saves the converted file with just two channels. I believe that it just pulls the front left and right channels, and does not down-mix 5.1 (for example) to stereo.

See the third paragraph in my post here: http://yabb.jriver.com/interact/index.php?topic=92612.msg637577#msg637577

I am pretty sure that one of the developers, I think Hendrik, confirmed that for me at one time. But I can't find the post again. From memory, Hendrik also said it would be good to improve the formats available that the converter supports, but it was a can of worms in that the number of format combinations from source to target was enormous, so it would be difficult to work out which conversions to implement. I also think there was some issue around writing the AC-3 format. Possibly a licencing issue? But then I can get the converter to write AC-3, but only in stereo.

I started doing some more testing a little while ago, converting from JTV to TS to see if I could get 5.1 output from 5.1 AC-3 source. It was depressing. The best I got was stereo AC-3. Often I get stereo AAC.

Therefore, to answer your question OverTheAir, yes, the Convert Format tool only supports output of two channels. I would love someone to prove me wrong, but I won't hold my breath.

If you haven't, also read this thread: http://yabb.jriver.com/interact/index.php?topic=92387.0
Specifically, given the constraints of the Convert Format tool, and the benefits of using the JTV format, I have decided not to use the TS format. Yaobing explains the main benefit of the JTV format here: http://yabb.jriver.com/interact/index.php?topic=92387.msg636416#msg636416

[OverTheAir]

RoderickGI, thanks for yet another of your detailed, helpful and informative posts. 

In my case I never watch live TV, so there is no benefit from the JTV format for me.  I too really wish the JR team would give some thought to implementing at least some options for supporting 5.1 channel "conversion".  The puzzler for me is that AC-3 would be a straight pass through of the audio without even a need for AAC conversion.

So to illustrate for others why I started this thread.  I recorded the PBS program The Bomb http://www.pbs.org/program/bomb/ the other day.  At approximately 2hrs run time it created a ~10.5GB TS file, which actually isn't that bad since US Antiques Roadshow (1hour program) routinely takes 6GB to 6.5GB.  After conversion using MCEBuddy, some small edits with Avidemux and elimination of the mono Spanish and French audio (just 165MB for these) the Bomb is now 4.3GB with the original 5.1 channel audio and AVC video. 

Those type of savings add up over time and many recordings which is obviously why built in conversion is such a benefit.  I think most would agree we also want the option to keep as much as possible of any original media experience, whether that's CD, DVD, Blu-ray, SACD ... or in this case HDTV ... and have the option to discard what we don't need.  And then of course we also want quality metadata, which unfortunately is where my current solution falls down on a practical basis.