New V2 not operating correctly

[Trev]

The following is a copy I sent to Beyonwiz who have asked me to post this on the forum hoping that some light might be shed on what is going on.
Have recently purchased a V2 and familiarised myself with it’s functions and operation.
During this time I have discovered some problems and hoping with your help that they can be rectified.
I have reset the V2 back to Factory Default Settings.
Menu Setup – Expert
V2 changes from Factory Defaults are:
System > Button Setup > Skip L/R 60sec
Skip Up/Dn 180sec
Record & Playback > Margin before 2 min. Margin after 5 min
AV Settings are Video Output HDMI 1080p
No SD card installed in V2
Nothing plugged into USB 2 socket
USB 3 Socket - Seagate 2TB Cache 6Mb 7200RPM 3.5” HDD
Sony TV KD-49X8000G HD 1080 x 1920 TV Receiver
V2 System Build – 20191106

The bigger problem is listed as follows:
I prefer to use the FF/Rewind feature during playback on the V2.
Whilst playing back any recorded program event eg: 9 News/Landline/Documentaries/Movies, pressing the FF x2 (or x4, x8, etc) button, the picture playback is not a steady stream of video information. Initially from pressing the FF x2 button, the picture will jump forward by periods that vary from between 30 sec to 90 sec approx. The video info on the screen is seen as a surging display with varying playback speeds until the Play button is pressed for normal play.
Picture playback is seen as a constantly fluctuating image varying in speed when FF button pressed.
Hope the following explains what is happening during Playback.

Recorded program during playback >>> time

Normal Play x1 Initial x2 speed x2 speed x2 speed Normal Play x1
| | | | |
------------ ►►-------------------|____|--------------------|____|--------------►-------------------
| | | |
Press x2 Playback speed Playback speed Press Play
(or x4, etc) constantly fluctuating constantly fluctuating
that vary between that vary between
30-90 secs 30-90 secs

The above is repeated until the Play button is pressed for Play x1

Also the following occurs during a live program using Timeshift, pressing the x2 Reverse, the speed starts off normally then picture will freeze temporarily and time will oscillate up/dn by 20, 30, 40, secs or so in time as displayed on the timeline top left of screen and not advance towards the beginning of the Timeshifted program.
Pressing Play resumes normal Play.
Have had the situation above where the following has happened.
Pressing the Play button resumes Timeshift. Now pressing FF x2 button, the playback speed is in excess of x2, taking 15min of Timeshifted event to be played back in 30 secs before I pressed the Play button to resume normal Play.

I have substituted a 2.5” HDD in place of the 3.5” HDD with the same results.

Thanks in advance.

[prl]

I don't have a good solution for you. You might like to look at this recent topic: Live Rewind Woes on V2.

[peteru]

I prefer to use the FF/Rewind feature during playback on the V2.

I stopped reading here.

The answers is don't do that. There is no way that the hardware could decode most streams faster than at 1.5-2.0x speed to give smooth playback. The hardware is optimised for real-time playback of digital video. Trickmode playback is implemented by seeking to keyframes. Different codecs and codec settings have different frame structures and thus the experience when seeking will vary. At the end of the day, trying to use FFWD or REW playback is asking the hardware to do something it was not designed to do on data that is unsuitable for that kind of access pattern.

Start using the skip buttons to navigate, your life will be much better as a result.

Suggested skip button settings are:
Left: 4 seconds
Right: 15 seconds
Up: 180 seconds
Down: 50 seconds

[Trev]

Coming from an electronics background, I find it hard to accept the response given.

The reply provided –
I stopped reading here.
The answer is don’t do that. There is no way the hardware could decode most streams faster than 1.5 – 2.0x etc etc.

The remedy given here just merely side stepping a FF/Rew user function that is available on the V2
and to use the skip function during playback, is just avoiding what is clearly a system operational fault.

All video and audio signals are encoded and decoded (as well as numerous other functions) processed by the SoC (system on chip) Hisilicon ARM Cortex A5 Hi 3798MV200 processor.

Ideally, during playback using FF/Rew, the decoded stream should provide smooth video playback at the selected speed. Unfortunately, what is seen on screen is a video image during
FF/Rew playback which is constantly varying in speed. This would seem to indicate an unstable frequency/clocking fault.

Reading posts on the forum re this problem, it would appear that some other users would prefer using the FF/Rew buttons during playback, and perhaps the Beyonwiz staff/Engineers could look into the FF/Rew feature that is part of the operating system of the V2 to come up with a suitable fix.

[prl]

The relevant parts of the code are the GStreamer media framework, which is open source, but not worked on much by the people here who work on the Beyonwiz code. The most likely source of the problem, though, is in the System-on-a-Chip manufacturer's SDK (possibly the device drivers) which is proprietary. The only way to have that code fixed is through the chip manufacturer.

The upper levels of the Beyonwiz firmware is based on the Enigma2 open source PVR software. That part of the Beyonwiz code is largely maintained by people who post on the forum rather than Beyonwiz staff (of whom there are few).

[prl]

BTW, if you want to quote a user in a reply, click on the double quote icon at the top of them post you want to reply to, then edit out any part of the quoted text that's not relevant to your reply, being careful not to disturb anything in the [quote ...] or [/quote] markers.

The Preview button on the post entry page can be used to check that the quote has worked out the way you wanted it to.

That way, it's clear which part of the post is the quote and which is your text. It also provides an automatic link back to the quoted post so that a reader can easily go back to the quoted post and read that.

[peteru]

Coming from an electronics background, I find it hard to accept the response given.

Coming from an electronics background you should be aware that there are constraints on a system with limited bandwidth, power & memory capacity that just can not be exceeded. It does not matter that in theory something is possible. If the silicon and firmware has not been designed and built to do the things you are asking for, it's just not going to happen.

All video and audio signals are encoded and decoded (as well as numerous other functions) processed by the SoC (system on chip) Hisilicon ARM Cortex A5 Hi 3798MV200 processor.

Ideally, during playback using FF/Rew, the decoded stream should provide smooth video playback at the selected speed. Unfortunately, what is seen on screen is a video image during
FF/Rew playback which is constantly varying in speed. This would seem to indicate an unstable frequency/clocking fault.

That's not how it works.

Very little is done by the ARM processor. All the ARM CPUs do is set up the various hardware decode pipelines and other IP blocks. The rest is done by the various dedicated hardware. These are fairly complex and long pipelines. They take a long time to fill and synchronise. There are many tradeoffs there and a lot of complexity. I could write a couple of book chapters explaining how this all works under the hood.

Yes, there is some scope to make the existing silicon behave marginally better, but most of that effort would have to be done by Huawei / HiSilicon and they in turn would rely on Vivante. Unless you are a high volume customer (say a few million SoCs per year) and locked into using that specific SoC, that's unlikely to happen. Maybe there is also some scope for making the drivers behave better, but again, unless the ODM that Beyonwiz uses for the V2 sees some major new business coming out of this, the prospects appear slim. Remember, we are looking at dealing with Chinese manufacturers, so you need to start talking about orders in the hundreds of thousands of units or more before you get their attention.

The advice I am giving you here is very pragmatic. You could insist that the V2 should behave like a VHS VCR or a mini-DV camcorder and be frustrated by the fact that it can't do it. Or, you can accept that skipping is the way that the V2 works better and embrace that mode of operation. It may take a little while to get used to it, but most of us did it.

BTW: When I switched to digital 20 years ago, the thing I missed most from my semi-pro, field accurate, S-VHS deck was the excellent scrubbing performance with the jog/shuttle wheel, including having audio during trick play.