Auto resolution and the 544x576 channels

[aido]

I've been doing some testing on a new 4k TV and it seems to offer the best SD scaling when the resolution of the box is forced to 576i - if I use the automatic resolution settings it scales the 544x576 channels to 1920x1080i first which the TV then has to rescale again.

I found info from this post explaining why it's done:
http://www.world-of-satellite.com/showthread.php?47609-Resolution-for-unsupported-SD-resolutions&p=371832&viewfull=1#post371832

The picture quality does seem to improve for me when letting the 4k TV scaler in this set do all the work.

Is there anyway of overriding the automatic resolution setting for the lower than <700 pixel wide channels please so that they can be left at 576i while still being able to watch the HD channels in full HD?

[Trial]

Hi,
the reason is still valid. When the box should display 544x576 it first scales to 720x576 and your TV then to 4K or whatever. So scaling of the VU cannot be disabled for this resolution and these small factors are more critical for the PQ. You can try the original image and the plugin AR which does not care about logic. Then you can really see if it is noticable better and perhaps post some screen shots here.

ciao

[aido]

That's what I mean though, the box itself is scaling the 544x576i channels not to 720x576i but to 1920x1080i so you have the OpenVix box doing that conversion and then the TV doing another.

The 720x576 channels get left at that for the TV to scale, just the 544x576 channels go straight to 1920x1080i?

[Trial]

Hi,
you did not get the point. Even when you set that 576i should be output it is scaled and the scaling factor (720/544) is very small which is more difficalt to scale then 1920/544. You will never get an unscaled image from a box when the width is <700.

As I said compare with another image where the old normal AR is running. Perhaps make screen shots with the web interface from vix scaled to 1920x1080 and the other image scaled to 720x576 and then compare on your TV.

I have the opinion that double scalling is evel and should be avoided.

ciao

[aido]

I totally agree that double scaling is evil :)

I've noticed for a while that on the LX3 SD content has had what looks like vertical lines down it as though something is scaled incorrectly and you notice it most on the bridge of peoples noses between their eyes - this is there after fresh flashes etc.

As a test I have just recorded something from Comedy Central which was 544x576 content and then copied the .TS file up to my server and then watched the same video file both directly from the TV and on the OpenVix LX3 box.

When watching the recording on the LX3 it has the same problem as the live feed with vertical imperfections shown as lines.

When watching the same TS file directly on the TV these are pretty much gone and it looks nicer.

Where would the code be to change what the 544x576 video is scaled too please so I can try it with some slightly different values (I'd try going up down 16 pixels in total to see if I can get rid of the line effect).

Thanks :)

[Trial]

Hi,
I think this is done in hardware. I am not aware of a position where you can decide which which resolution should be used as output.

ciao

[aido]

OK I'm guessing it's this one:

https://github.com/OpenViX/enigma2/blob/master/lib/python/Screens/VideoMode.py

And this bit of code:


if video_height and video_width and video_pol and video_rate:
resolutionlabel["content"].setText(_("Video content: %ix%i%s %iHz") % (video_width, video_height, video_pol, (video_rate + 500) / 1000))
if (700 < video_width <= 720) and video_height <= 480 and video_rate in (23976, 24000, 29970, 59940):
new_res = "480"
elif (700 < video_width <= 720) and video_height <= 576 and video_rate in (25000, 50000):
new_res = "576"
elif (video_width == 1280) and video_height <=720:
new_res = "720"
else:
new_res = config_res
Is there anyway to figure out if the box is scaling the 544 up to 704 or 720 or 1024 that you know of please as maybe that's what is causing this to look wrong (ie the channel is being scaled incorrectly by the driver maybe?)

On one of the channels having a problem here in the UK I've taken a screenshot in VLC and it's come out at 1024x576 so it's a 16:9 channel. It just seems weird that something seems to be using a different scale factor on vertical to what it uses on horizontal.

[aido]

OK now I'm super confused - I was going through various settings and after setting cat /proc/stb/vmpeg/0/pep_block_noise_reduction to 1 and then back to 0 the problem appears to have disappeared.

I googled some of the settings in that folder which took me back to the Video Enhancement plugin which I then installed.

I've been playing with various settings and it looks like after installing the video enhancement plugin if I move the value upwards it again creates the vertical lines but when I return it to 0 they are pretty much gone. Before the box has been behaving for literally over a month like the setting was at 5.

What I don't get is that the value of that setting was 0 to start off with so why would increasing it and then setting it back to 0 seem to fix the problem?

I've rebooted the box and the problem appears to have fixed itself - I'm at a loss as to what happened there though but SD playback is most definitely improved here :)

[Trial]

Hi,
this is only the code for AR this has nothing to do what the box really does. There is no option bypass video so all videos that do not fit are scalled by the box.

ciao

[aido]

I updated my LX3 to build 033 at the weekend remotely and now I'm home I've noticed the problem is back.

I'd removed the Video Enhancement plugin not long after this post and things had been perfectly fine across all SD channels.

Now the box was behaving like the block noise reduction was turned right up again after build 033.

I reinstalled Video Enhancement and turned block reduction up to full and then back to 0 and it's fixed the problem again.

Are you guys changing this setting in the new builds or something?

[Trial]

Hi,
I think your settings are only applied when the plugin is there. So change some settings remove the plugin and remove the plugin. I would say that your settings are not applied then. E2 is applying nothing on its own so the settings will be default.

ciao

[aido]

Same problem after a fresh install of 4.0.003 on the LX3 here with the dodgy scaling on SD channels - Sky 1 showed it straight away with vertical lines visible.

SSH'd in and just did the following:

root@xpeedlx3:~# cat /proc/stb/vmpeg/0/pep_block_noise_reduction
0
root@xpeedlx3:~# echo 1 > /proc/stb/vmpeg/0/pep_block_noise_reduction
root@xpeedlx3:~# echo 0 > /proc/stb/vmpeg/0/pep_block_noise_reduction
root@xpeedlx3:~# cat /proc/stb/vmpeg/0/pep_block_noise_reduction
0

As soon as you do the first one it gets rid of it and then setting back to 0 it works fine with the weird scaling gone.

It's weird that the box is coming up with a fresh flash with the setting ok but then toggling the setting on and off fixes the problem?!

[aido]

OK I just tried a full image couch flash restore back to defaults on the latest 4.2.003 and setting the box up from scratch without restoring anything - same problem (ie you can see vertical lines in loads of content and most noticeable between the bridge of someones nose and eyes) so it was nothing to do with any old settings I was using.

Also it was doing it on normal SD channels such as Sky News which is 704x576.

If any of you are having problems with your SD quality on the LX3 then just telnet in and run:

echo 1 > /proc/stb/vmpeg/0/pep_block_noise_reduction
echo 0 > /proc/stb/vmpeg/0/pep_block_noise_reduction

I'm not sure why it's just me seeing this though.

[aido]

Just to confirm Auto resolution has nothing to do with this but I can't edit the title now I know better - the box is running on 1080i output with the refresh as multi and weird scaling artefacts are generated until you run the commands above.

[skippie]

I see the vertical lines on my TV also, this since 4-version

Sent from my U65GT using Tapatalk

[skippie]

same settings : gigablue set to 1080i and multi

Sent from my U65GT using Tapatalk

[aido]

Thanks for the feedback - have you tried those two commands to see if it fixes it for you as well please?