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There is only one possible way that a recorded programme can have a different outcome from Live TV. And that’s when viewing a recording you are replaying a different audio track to that you are using when viewing Live TV.
A digital broadcast is contained within a container. Eg SD TV uses a .ts transport stream container. Within this container there can be multiple audio and subtitle streams. Because it’s a digital data stream when you record it the whole data is recorded as is to file on the hard disk. A tuner is required to extract the required data to send it to the hard disk. Watching live the tuner passes the stream to the box audio and video decoders.
Replaying a recording needs no tuner because the data is passed directly to the box video and audio decoding circuits and output from HDMI and any other digital outputs like a toslink socket. So exactly the same data as when it was live is available.
So any large difference has to be down to how you are delivering the audio to the only analogue transducers in the system ( That’s the loudspeakers that turn analogue audio into the sound you can hear ?
Such large errors have to be down to multiple encoding and decoding in series.
Perhaps to a TV and exported back to a AVR using ARC. I do not have an issue because in both cases the output is to a hdmi port on my AV receiver, which does the required audio decoding and sends the audio to my speakers.
Recordings made on my Aura from HD TV (I never record SD – with a big 4K OLED the quality hit is immediately clear). Replayed recordings look exactly the same as the live broadcast which as it’s the same data it must be the same.
I will try recording a short video clip of a recording playing back from a HD recording and upload it to a file share site. VLC should play it back OK.
20 second clip from BBC1-HD with someone talking.
https://www.adrive.com/public/x2WJ2v/HDRecording_LipSynch.mp4
Hi Graham – thanks for your info and the clip – unfortunately, the URL for the clip takes me to A-Plan with the message that this is no longer publicly available. Is there something I can do to get at it, or would it be better to email it to me ? Thanks
Re the Aura problem, I have reset the box in case I screwed up a setting along the way, and am going through some recording then testing – will let you know the outcomes – Thanks again
Lefteris – 2 mins ago »
Re the Aura problem, I have reset the box in case I screwed up a setting along the way, and am going through some recording then testing – will let you know the outcomes – Thanks again
Same for me I can only assume it’s some sort of copyright restriction though why a 20 second clip of a TV screen could be an issue, I have no idea. I can cut it down to a few frames and try and e-mail it if you want to PM me an address. I will post final size first.
Struggling. I have a video clip but it’s upside down (landscape auto rotate on phone) I will have to dig out my camcorder or film in portrait
Portrait video hope you can see lip synch
It’s only 5MB but will not upload. guess it will e-mail if you want to pm me a address
Hi again – OK, I have recorded several programmes in SD and HD – they all playback fine on the Aura itself. However, when playing a previously recorded video which is on my NAS (tried .ts, .mp4 and .mpeg files), using Kodi or VideoLan, the audio is behind the video by how much I obviously can’t measure, but it’s enough to make it unwatchable. Tried all sorts of settings both in Aura and Kodi (not possible to change settings in VideoLan on Android), but I cannot improve the sync. Is there a better media player for the Aura, or maybe somewhere I can troubleshoot the Kodi settings to get them right ?
An additional quirk I have found is that yesterday I recorded 3 programmes on the Aura but only 2 showed up in Recordings – using FX they are there in the Recordings Folder – does Humax already know of this, or should I lodge a ticket with them ?
PS – Live programmes are fine
Correction – the file that didn’t show up in Recordings didn’t actually record although it appeared in the Recordings folder as an empty .ts file, and only had the index.idx file with it (normally there are 7 additional sidecar files)! Looking at its properties, it is of zero bytes in length – it was from Pick and I don’t usually have trouble recording off Pick, but maybe there was a DRM problem which the Aura picked up. I have recorded previous episodes of the series (Instinct) on the FVP5000 with no problem
Lefteris – 22 mins ago »
Hi again – OK, I have recorded several programmes in SD and HD – they all playback fine on the Aura itself. However, when playing a previously recorded video which is on my NAS (tried .ts, .mp4 and .mpeg files), using Kodi or VideoLan, the audio is behind the video by how much I obviously can’t measure, but it’s enough to make it unwatchable. Tried all sorts of settings both in Aura and Kodi (not possible to change settings in VideoLan on Android), but I cannot improve the sync. Is there a better media player for the Aura, or maybe somewhere I can troubleshoot the Kodi settings to get them right ?
An additional quirk I have found is that yesterday I recorded 3 programmes on the Aura but only 2 showed up in Recordings – using FX they are there in the Recordings Folder – does Humax already know of this, or should I lodge a ticket with them ?
PS – Live programmes are fine
Download mediainfo
https://mediaarea.net/en/MediaInfo/Download
Open the Video file that is causing the Issue
Select view – Tree and export the results to a .txt file. Post the text here
Try playing the file on a PC using VLC Player.
TSmuxer GUI can remux files and set a user delay for the audio.
Live TV has a built in audio delay of around 1000msec. Bu that should also be present in recordings the aura makes. Guessing the file you have issues with has a much smaller delay
Mediainfo will tell you the delays.
This is the file which didn’t record – Instinct
It would not play on my PC using VideoLan
Another Aura recording which appears OK on the Aura is The IT Crowd, but on the PC played after downloading to my NAS drive had an audio delay – using MediaInfo (amazing utility!) it shows the Delay as 1 s 720 ms
Also the same delay if played back on the Aura using Kodi
Lefteris – 6 mins ago »
Another Aura recording which appears OK on the Aura is The IT Crowd, but on the PC played after downloading to my NAS drive had an audio delay – using MediaInfo (amazing utility!) it shows the Delay as 1 s 720 ms
Also the same delay if played back on the Aura using Kodi
I need to see the full Mediainfo text. Particulary the video codec used to compress the video.
Note .mp4, .MKV, .ts are not file types. They are containers. The video contained in a .mp4 container may or may not use mpeg4 to compress the video.
Use tree view to export the analysis to a text file and simply paste it into a paste it into a post. It’s only a small file.
Decoding mpeg video always takes longer than mpeg compressed audio. That’s why the audio needs to be delayed. Only if the video is not compressed so no decoding is required and the audio should be in sync
The delay you quote is about right for H64/AVC or mpeg 2 video compression codecs.
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