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HD File Formats

J

jonmitch

New Member
Hi Everyone,

Quick question regarding the file format used by the Humax for the HD transport streams ...

Firstly, I have the custom firmware, and I have ensured all the recordings I am looking at are decrypted. I am still struggling to work with the HD .TS files though.

I read somewhere (probably here, but can't find it now), that within the .TS file, the HD files are basically just MP4 files (H.264 encoded) within the .TS wrapper. It therefore makes sense to me that if I open the .TS file in VideoReDo and save it out as a MP4 file I will not be transcoding the video (thus saving me quality and time). However, this doesn't seem to work - VideoReDo stalls with about 3 seconds remaining, and when it eventually finishes (if left overnight) the video & audio in the resultant file drift in and out of sync on playback.

As an experiment, I tried saving it out from the .TS file as an MKV file instead, and this worked perfectly. File size is a little less - so maybe it is transcoding and throwing away information ? Unlikely, given that it is quite quick.

So, can anyone elaborate on the differences between MP4 and MKV in the context of extracting the files from an HD .TS file ?

Thanks,

Jon
 
A standard definition *.TS files is basically and MP2 file and a Hi-Def. *.TS file is a H.264 file. MKV and MP4 are also containers / wrappers that can contain various different video file formats. I presume if you are working on Hi-Def. files that you are using the H.264 version of VideoReDo as the other version won't handle Humax Hi-Def. files at all. I would say that if VideoReDo stalls with only 3 seconds remaining, that the programme is working, is it possible that it is running out of disk space and crashing due to that?. You would expect the files size to be smaller as it is when you save a Standard Def. files as MPG using the Web-if 'Extract to MPG' option, this is because a lot of non video data is stripped out of the *.TS file during the process
 
Thanks Ezra.

Yes - I am using the H.264 version of VideoReDo. So it sounds like it makes no difference whether I extract to MP4 or MKV then ? Don't think it is a space issue - the drive it is writing to has more than 100GB left. Makes sense with the smaller file sizes due to stripping stuff out - now you mention it I remember finding the same with extracting SD files to MPG.

Thanks,

Jon
 
It's a while since I tried VRD H.264. In the end I didn't buy it because, although it would edit Hummy HD files perfectly well, it frequently failed when saving and usually had to recode, which it did very slowly. The only reliable output format when I tried it was .ts.
 
I've also found that saving VideoReDo H.264 edits to .ts file is the quickest and least troublesome method. I then use Handbrake to transcode them to .mkv. Handbrake will convert .ts to .mkv and compress hummy files to well under half the original file size with negligible quality loss. Bit of a steep learning curve to get the best out of Handbrake but it's worth it.
 
If you transcode to mp4 with Handbrake, you'll be able to play them with the Humax (and almost anything else). You can't play mkv files on the Humax. I can't really see the point of mkv for simple media files with a single video stream and a single audio stream: their strong point is handling multiple streams within a single file.
 
fenlander said:
If you transcode to mp4 with Handbrake, you'll be able to play them with the Humax (and almost anything else). You can't play mkv files on the Humax. I can't really see the point of mkv for simple media files with a single video stream and a single audio stream: their strong point is handling multiple streams within a single file.
Click to expand...

Get your point regarding the lack of benefits of mkv files, but the humax will play mkv files.

It does struggle with some audio streams when in the mkv container that its fine with when in the mp4 container so I agree that mp4s are the way to go if you're encoding files yourself.

Sent from my GT-N7100 using Tapatalk 2
 
Trouble is, you never know when an 'imported' mkv is going to crash the Humax - in my experience, it's more often than not. So mp4s are the safe option. Of course, if you encode your own mkvs and have arrived at a formula that works, all well and good.
 
Its ac3 audio that the humax doesn't like when contained in a mkv wrapper so as long as you keep clear of that you should be fine :-)

ac3 audio in mp4 wrapper works fine though.

Mp4 definitely the best option if you have a choice - just dont give up on the mkv's you already have.

And if the op can only produce mkv's for some reason then they're not loosing out. Same audio and video streams either way.

Sent from my GT-N7100 using Tapatalk 2
 
Thanks guys, for all the responses. For whatever reason, using VideoRedo (the only simple and reliable way I have found of editing Humax .ts files and extracting the .mpg for SD files) does not like extracting .mp4 from the HD .ts files - but it seems to like extracting .mkv files from the HD .ts files. However, having experimented a little more I seem to have hit a couple of other problems.

1) Extracting from HD .ts files to .mkv files is not always as reliable as I thought. The slightest thing (maybe a glitch in the .ts file ?) makes the extracted .mkv corrupt for a good few minutes. This is hopefully going to be fairly straightforward to work out - and I shall probably start by experimenting with Selectortone's method of editing and saving to a .ts file in VideoRedo, then extracting the .mp4 or .mkv file using Handbrake. Note, I want to extract the file, not transcode, as I want to avoid any quality loss.

2) I am having trouble "seeing" all the audio from the file. This needs a little more explanation ...

My current setup is to take the SD and HD .ts files from the Humax, and edit them in VideoRedo. I then extract the .mpg or .mkv file (SD or HD respectively) and move these files onto a hard drive on my Mac Mini (running XBMC). When checking a few of the HD .mkv files I had made, I noticed that XBMC was reporting that they had 5.1 audio - yet all I could get out of the Mac Mini was Linear PCM audio. I understand that the HD Freeview signals carry Dolby Digital+ (E-AC-3), and am wondering if this is the problem.

I know I can get "standard" Dolby Digital out of my Mac Mini - ripped DVDs successfuly have DD5.1 and even DTS. This is all fed from the Optical out on the Mac Mini to my Surround Sound Processor. HOWEVER, my Surround Sound processor does not handle DD+, and nor (as far as I know) does the Mac Mini - so I am assuming that this is the problem. Is there a way of converting the E-AC-3 audio to standard AC-3 during the process of extracting the .mkv (or .mp4) from the .ts file - either in VideoRedo or Handbrake ? Am I barking up the wrong tree ?! Incidentally, playing the original recordings on the Humax I still can't seem to get 5.1 sound out of them either. The Humax is connected to my Surround Processor by Optical Cable as well.

I am also wondering if the audio problem would be resolved by using the HDMI out of the Mac Mini and Humax for Audio - but sadly my Processor is older and does not have HDMI inputs (that's another upgrade ... hopefully soon).

So, am I going round in circles here ? Is there an easy way to get the 5.1 audio that I believe is present in the HD Freeview recordings ? Given that I can't even get the 5.1 audio out the Humax I am wondering if it is my system ...

Thanks,

Jon
 
Are you sure the input file is definitely 5.1 ? Not all hd broadcasts on freeview are - in fact I believe most aren't.

Sent from my GT-N7100 using Tapatalk 2
 
I use VideoReDo for HD recordings & found it would crash regularly at the end of files until I started to shrink them 1st on the Humax to remove the EPG data, after that I have had no issues.


Sent from my GT-I9300
 
If you use something like VLC >> tools >> codec information, you can see whether the file has a DD5.1 audio stream

VLC-file-info.jpg
 
Thanks guys, I will have a play with shrinking on the Humax as well. I agree not many HD programs are actually 5.1 - but the XBMC specifically flags up some as being 2-channel and some as being 5.1 channel. VideoRedo also describes the ones I think are 5.1 as being 6-channel.

I suppose a more pertinent question to help my diagnose would be - has anyone managed to get 5.1 sound from their Humax box, via the Optical SPDIF output, into a Surround Sound Processor that handles DD5.1 and DTS (but not DD+) ? AT the moment I cannot even get that working - hence I suspect my setup to be wrong somewhere.

Thanks,

Jon
 
jonmitch said:
has anyone managed to get 5.1 sound from their Humax box, via the Optical SPDIF output, into a Surround Sound Processor that handles DD5.1 and DTS (but not DD+) ?
Click to expand...
Yes. If you have any Later with Jools, or films recorded, Blade runner broadcast a while back is DD5.1 in my amp via spdif from hummy.
 
Same here, the info. in #15 is from a Jools Holland - Later program, as long as you have the Humax set to multi-channel DD5.1 will be sent to the SP-DIF and if the HDMI device is DD5.1 compatible, it will be sent to that as well
 
The discussion seems to be drifting from processing TS files to the Humax's optical output. The content of the TS file is whatever that is transmitted over the air. On Freeview HD, multi-channel audio is encoded in AAC. Freeview does not use Dolby Digital. The Humax will however convert AAC to Dolby Digital AC3 on the fly on its optical and HDMI outputs if it is told to output multi-channel audio. In short, what you get from of the optical output is not the same as what's in the TS file.

It is also worth mentioning that the TS container is very flexible and allows the broadcaster to change the aspect ratio of the video, the audio encoding, from interlaced to progressive frames, mid stream. The British broadcasters do all of the above. Other video containers may not have the capability to accommodate such changes - many use a single header to describe the video/audio formats at the beginning of the file and expect them to stay the same. That's why converting TS files to other formats can be hit and miss.
 
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