Forum › Forums › Freeview HD › Aura UHD › Picture pixellation while watching in pause mode
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grahamlthompson.
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January 15, 2021 at 7:43 pm #21404
Anonymous
InactiveLike others have previously commented I have seen occasional picture break up and pixellation issues. I too initially thought it was maybe an RF signal quality issue, but given I have multiple DTV devices in the house fed from the same distribution system was mystified as to why. Checking the signal strength for each mux on this box they are between 66 and 82, all with 100% quality. The COFDM signal is generally pretty robust so unless there was interference either external or internal to the box it ought not to be the culprit.
What I have started to notice though and verified when it happened last night is that I was watching the recording effectively in “live pause mode”. That is the programme was being recorded whilst at the same time I was watching it. I had pressed pause for a few minutes and then continued watching. Several times during the programme there were brief bursts of pixellation. When I watched the recording back again today at the points where the errors were, the recording appeared fine. That seems to rule out signal issues as being the cause in my case.
It makes me wonder therefore if there could be hard disk/filesystem issues which mean that occasionally the playback buffers cannot access data quick enough. Last night I was recording 2 HD streams and playing back 1 HD stream. I would hope that if I’m recording a channel, watch it and then press pause that it uses the stream its already recording rather than starting a new “Pause Buffer”. Otherwise that could be 3 HD streams to record.
Just wonder if this could be the same scenario where others have observed picture break up. Don’t know whether it is then related to number of record streams, time delay etc.
January 15, 2021 at 8:22 pm #100797grahamlthompson
ParticipantGeoff Thompson – 25 mins ago »
Like others have previously commented I have seen occasional picture break up and pixellation issues. I too initially thought it was maybe an RF signal quality issue, but given I have multiple DTV devices in the house fed from the same distribution system was mystified as to why. Checking the signal strength for each mux on this box they are between 66 and 82, all with 100% quality. The COFDM signal is generally pretty robust so unless there was interference either external or internal to the box it ought not to be the culprit.
What I have started to notice though and verified when it happened last night is that I was watching the recording effectively in “live pause mode”. That is the programme was being recorded whilst at the same time I was watching it. I had pressed pause for a few minutes and then continued watching. Several times during the programme there were brief bursts of pixellation. When I watched the recording back again today at the points where the errors were, the recording appeared fine. That seems to rule out signal issues as being the cause in my case.
It makes me wonder therefore if there could be hard disk/filesystem issues which mean that occasionally the playback buffers cannot access data quick enough. Last night I was recording 2 HD streams and playing back 1 HD stream. I would hope that if I’m recording a channel, watch it and then press pause that it uses the stream its already recording rather than starting a new “Pause Buffer”. Otherwise that could be 3 HD streams to record.
Just wonder if this could be the same scenario where others have observed picture break up. Don’t know whether it is then related to number of record streams, time delay etc.
Interesting. I will setup a recording test tomorrow . Pretty sure that does not happen. Done this many times. One thing I have noticed. I have all my kit connected to a AVR. I can select a different source box while the Aura is paused.
That means the box loses handshake. On returning to the aura input. the pause has been released and playback returns to the beginning. The recording buffer is complete. You just have to skip forward to where you stopped viewing.
Doing the same with the other two boxes and pausing between a HDR-1000S and FVP-5000T, reselecting the input finds the content remains paused at the point the alternate input was selected.
Anyone with a TV with different boxes selected to different HDMI inputs could try the same experiment. I only have one HDMI cable from AVR to 4K TV.
January 29, 2021 at 5:29 am #100798Anonymous
InactiveLike others have previously commented I have seen occasional picture break up and pixellation issues. I too initially thought it was maybe an RF signal quality issue, but given I have multiple DTV devices in the house fed from the same distribution system was mystified as to why. Checking the signal strength for each mux on this box they are between 66 and 82, all with 100% quality. The COFDM signal is generally pretty robust so unless there was interference either external or internal to the box it ought not to be the culprit.
What I have started to notice though and verified when it happened last night is that I was watching the recording effectively in “live pause mode”. That is the programme was being recorded whilst at the same time I was watching it. I had pressed pause for a few minutes and then continued watching. Several times during the programme there were brief bursts of pixellation. When I watched the recording back again today at the points where the errors were, the recording appeared fine. That seems to rule out signal issues as being the cause in my case.
It makes me wonder therefore if there could be hard disk/filesystem issues which mean that occasionally the playback buffers cannot access data quick enough. Last night I was recording 2 HD streams and playing back 1 HD stream. I would hope that if I’m recording a channel, watch it and then press pause that it uses the stream its already recording rather than starting a new “Pause Buffer”. Otherwise that could be 3 HD streams to record.
Just wonder if this could be the same scenario where others have observed picture break up. Don’t know whether it is then related to number of record streams, time delay etc.
I can confirm I get the same random pixelisation in live pause mode but if I play back the same section after the recording has completed the play back is perfect.I hope any future software update resolves this issue as the latest update has not.
January 29, 2021 at 10:01 am #100799Martin Liddle
Participanthowarp – 4 hours ago »
That is the programme was being recorded whilst at the same time I was watching it.
You haven’t made it clear whether you were playing back the recording (what is usually called chase play) or just watching the recording live?
I had pressed pause for a few minutes and then continued watching. Several times during the programme there were brief bursts of pixellation. When I watched the recording back again today at the points where the errors were, the recording appeared fine. That seems to rule out signal issues as being the cause in my case.
I agree the signal levels are well below the levels where I would suspect tuner overload and your observation confirms that is isn’t a signal strength issue.
It makes me wonder therefore if there could be hard disk/filesystem issues which mean that occasionally the playback buffers cannot access data quick enough. Last night I was recording 2 HD streams and playing back 1 HD stream.
On the earlier Humax PVRs the hard drive is easily capable of dealing with that workload. Do we know what make and model of hard drive is fitted to the Aura? Again on earlier models the bottleneck is the chip set used which is chosen to cope with the normal peak load but not have much performance margin.
I would hope that if I’m recording a channel, watch it and then press pause that it uses the stream its already recording rather than starting a new “Pause Buffer”. Otherwise that could be 3 HD streams to record.
Again I can’t speak for the Aura but on earlier Humax models it would be using the recorded stream rather than a buffer.
Just wonder if this could be the same scenario where others have observed picture break up. Don’t know whether it is then related to number of record streams, time delay etc.
Some testing would hopefully show what is critical. If you could find a test case that reliably reproduces the problem then I suspect that would be very useful to the software developers.
January 31, 2021 at 9:13 am #100800Anonymous
InactiveAt last I think I’ve fixed my random picture pixelation problems. Very brief (approx 1 sec) and random picture pixelation was affecting my Aura output. Finally fixed by using a variable attenuator – initially the signal strength was up to 96% with 100% signal quality, then after reducing the signal until the signal quality fell below 100% then increasing it slightly back up to 100% this reduced the signal strength down to 58% – so the Aura tuners seem extremely sensitive and may overload very easily.
January 31, 2021 at 11:22 am #100801Martin Liddle
Participanthowarp – 2 hours ago »
Finally fixed by using a variable attenuator – initially the signal strength was up to 96% with 100% signal quality, then after reducing the signal until the signal quality fell below 100% then increasing it slightly back up to 100% this reduced the signal strength down to 58% – so the Aura tuners seem extremely sensitive and may overload very easily.
I would suggest increasing the signal strength a bit more to say 70% to have some margin.
January 31, 2021 at 7:48 pm #100802Anonymous
InactiveBack to the original topic.
This occurs in what some might call “chase play mode”, but to me as I am previously used to Sky, I would call “Live Pause”.
Generally I am watching with a relatively short delay when I have seen this, probably no more than 5 to 10 minutes.
The fact I am recording the channel at the time may be co-incidental but it provides the proof that it wasnt the signal. I think today I noticed it whilst just in the “live pause” mode, and when I skipped back, it then played OK.
I have tried to re-create, using extremely short delay, a couple of seconds, as I thought that may exacerbate the problem. However as it may only occur a couple of times in an hour long programme, its a lot of time to spend just to re-create it. Its a brief break up in a small area, so blink and you might miss it.
As Im usually watching in HD, and thats the only time I’ve seen it, I wonder if some of the additional process such as file encryption, decryption may also be at play or maybe its the file system and block sizes.
Unless there is something up with my hard drive, I’m surprised that no one else has noticed this.
January 31, 2021 at 9:18 pm #100803grahamlthompson
ParticipantGeoff Thompson – 1 hour ago »
Back to the original topic.
This occurs in what some might call “chase play mode”, but to me as I am previously used to Sky, I would call “Live Pause”.
Generally I am watching with a relatively short delay when I have seen this, probably no more than 5 to 10 minutes.
The fact I am recording the channel at the time may be co-incidental but it provides the proof that it wasnt the signal. I think today I noticed it whilst just in the “live pause” mode, and when I skipped back, it then played OK.
I have tried to re-create, using extremely short delay, a couple of seconds, as I thought that may exacerbate the problem. However as it may only occur a couple of times in an hour long programme, its a lot of time to spend just to re-create it. Its a brief break up in a small area, so blink and you might miss it.
As Im usually watching in HD, and thats the only time I’ve seen it, I wonder if some of the additional process such as file encryption, decryption may also be at play or maybe its the file system and block sizes.
Unless there is something up with my hard drive, I’m surprised that no one else has noticed this.
I regulary record up to 4-HD channels at the same time (never -SD) . However due to having a oled TV which are prone to screen burn from static images I turn off the screen when paused for a long period (not the TV the LG oleds can turn off just the display). Generally the same static image is shown on the kitchen LCD TV during a meal.
Not seen any image breakup but the kitchen TV is a Full-HD display not a 4K one.
February 1, 2021 at 12:50 am #100804Martin Liddle
ParticipantGeoff Thompson – 4 hours ago »
Unless there is something up with my hard drive, I’m surprised that no one else has noticed this.
Certainly it is true that if the hard drive is reallocating sectors then you see a very distinctive blip on the screen. I think I still favour the idea that something is struggling when the box is busy.
February 1, 2021 at 4:30 pm #100805Anonymous
InactiveSo last night we were watching The Serpent on BBC 1 HD which started at 9pm and at the same time recording ITV HD. We paused the programme for about 10 mins and then started watching, so with about a 10 minute delay buffer. I think I noted over a dozen times where the picture glitched, randomly spread throughout the programme. Each time I made a brief note of time and scene so I could review on the recording today.
As expected the recording appears perfect, no glitches.
One other strange occurrence last night was that about 15 minutes before the end the programme glitched and seemed to jump a scene. What I shortly discovered was that it had jumped back to real time without intervention, as we reached the end of programme before expected. We then had to rewind to watch the missing 10 minutes.
Its strange that if I try to recreate this effect during the daytime it never seems to happen. It only seems to happen on programmes I’m intent on watching which are often in the 9pm slot, so wonder if theres anything related to additional stream content these may carry such as audio coding type or audio description channel.
February 1, 2021 at 5:33 pm #100806Martin Liddle
ParticipantGeoff Thompson – 1 hour ago »
So last night we were watching The Serpent on BBC 1 HD which started at 9pm and at the same time recording ITV HD.
I am sorry but I am still not clear; are you actually playing the recording or just watching the live TV via the Humax? Generally in the situations you describe it is better, on Humax kit, to be playing the recording.
February 1, 2021 at 5:35 pm #100807grahamlthompson
ParticipantI have just watched a recording of Dancing On Ice from ITV-HD Sunday Box was recording Channel 4-HD while viewing the recording. Some picture break up noticed at times (not on paused content just on normal playback). May be 25% of the frame pixelated for a second or so.
February 1, 2021 at 6:08 pm #100808Anonymous
Inactivegrahamlthompson – 15 mins ago »
I have just watched a recording of Dancing On Ice from ITV-HD Sunday Box was recording Channel 4-HD while viewing the recording. Some picture break up noticed at times (not on paused content just on normal playback). May be 25% of the frame pixelated for a second or so.
Interesting, I also see the same on some recordings but it is not channel specific, just a momentary pause, a picture and sound break-up, then it carries on. Seen it on all four main HD channels but never when watching live.
The last one was on a Channel-5HD recording, so I noted the time index and went back after the program had finished, before deleting it, to see if it was a playback glitch or actually in the recording, checked it three times and it was exactly the same so I guess it was in the recording.
My signal strength is regulated by an attenuator (between 50-80%) but quality is 100%, I never saw this issue on the 5000T and it was set-up the same.
I’ve also had the odd recording with the Recording Failed logo next to it and it usually says because no or bad signal but 90% of the time there is no visible issue or it has a similar pixilation/sound glitch.
March 11, 2021 at 9:47 am #100809Anonymous
InactiveHi. I’m new to the forum having only acquired the Aura to replace an old YouView T1000.
I’m very pleased with the Aura, but I’m experiencing the same issue as what is being described in this thread…. that is momentary pixelation (less that a second) and/or momentary freeze of audio and video (again for less than a second), but only on Time Shift Recording (i.e I’m watching live t.v. that I’ve paused for a few minutes while I make a cuppa then go back and press play).
So if anyone else has witnessed this symptom, is there any obvious fix for it?
March 11, 2021 at 6:32 pm #100810grahamlthompson
ParticipantI might be jumping the gun here. This morning I noted that the HDMI out socket on the aura is located next to the RF sockets.
I curved the hdmi cable away from the rf cabling to form a loop, Curved it back over the rf cabling as far away as possible from the rf connectors.
HDMI cabling radiates RF in the energy band and the frequency varies with the current hdmi output.
So far not seen any picture breakup at all and this usually starts as it starts to get dark and effect live TV and recording output. Not noticed any on paused content but having an oled if going to pause for a significant period I turn the screen off on the TV.
The TV has voice control the command screen off turns off the screen in 5 seconds. pressing 1 turns it on.
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