Curious about picture quality (1 Viewer)

Alexh

Portal Member
October 30, 2016
27
0
58
Home Country
United States of America United States of America
Hi,

This is not a complaint per se. I'm running mediaportal on a sandybridge CPU, over HDMI to a 4k TV. TV reports 1080p input with OTA signals using hauppage PCI tuners.

My wife has a Comcast cable box, also 1080p.
I have noticed that the cable box picture quality is significantly better in terms of both sharpness and color saturation, even when I compare identical channels with the OTA being a 1080i signal. I can switch the HDMI input from cable to mediaportal to compare.

I have worked in video before and I know there are lots of variables but I thought that a 1080i OTA signal was about as good as it gets. Many OTA channels are 480 or 720 and in this case I assume Comcast is probably receiving a 1080i version so that's no surprise. Playing Netflix natively on the TV (I don't have 4k Netflix) is even better than the cable box for some shows.

We recently switched to the 4k TV but it actually seemed that the picture quality using the HTPC on the previous 1080p TV was better (was using mediacenter at that time).

When a microATX MB with HDMI 2.0 is available I'll build a new 4k HTPC but just wondering why the big difference.

Thanks
 

mm1352000

Development Group
  • Team MediaPortal
  • September 1, 2008
    21,577
    8,222
    Home Country
    New Zealand New Zealand
    Country flag
    Hello again

    My wife has a Comcast cable box, also 1080p.
    I have noticed that the cable box picture quality is significantly better in terms of both sharpness and color saturation, even when I compare identical channels with the OTA being a 1080i signal. I can switch the HDMI input from cable to mediaportal to compare.

    ...but just wondering why the big difference.
    Because you're not actually comparing identical channels.

    The source content (eg. channel WABC) and resolution (1080i) are the same... but this says nothing about bit-rates/bandwidth and encoding (ie. MPEG 2 vs. h.264).

    I have worked in video before and I know there are lots of variables...
    Yes, there are. Bit-rate, encoding, deinterlacing algorithm, RGB levels, colour space/conversion... and the list goes on.

    If you're interested in getting the best possible picture quality from MediaPortal, my advice would be to take a look at your:
    • GPU settings
    • video codec settings
    • refresh rate changing settings
    Perhaps worth a read:
    Guide: Perfect playback & Display calibration

    P.S. I've assumed that your TV settings (dynamic contrast etc.) are already optimal. That's a huge assumption. There's a good chance it's not valid. However, since you're comparing 2 HDMI inputs on the same TV...
     

    Alexh

    Portal Member
    October 30, 2016
    27
    0
    58
    Home Country
    United States of America United States of America
    Thanks! I was looking for a Mediaportal specific guide.

    The dynamic refresh was not set and also DXVA2 was not set. This seemed to make a difference.

    I'm using a HDMI receiver for audio - even in this case all of the LAV audio the LAV audio bit streaming should be disabled?
     

    Owlsroost

    Development Group
  • Team MediaPortal
  • October 28, 2008
    5,540
    5,038
    Cambridge
    Home Country
    United Kingdom United Kingdom
    Country flag
    DXVA2 was not set. This seemed to make a difference.

    ...which means (assuming you are using LAV Video Decoder) you have just switched from a software decoder to the Intel hardware decoder.

    When I switched from a lowish-end nVidia GPU to a lowish-end Intel GPU a while back, there was a noticeable lift in picture quality, particularly for MPEG2. I've been quite impressed by the Intel video decoding and de-interlacing performance. You might want to explore turning off the various Intel picture 'enhancements' in the Intel control panel - I think it looks better without them.
     

    mm1352000

    Development Group
  • Team MediaPortal
  • September 1, 2008
    21,577
    8,222
    Home Country
    New Zealand New Zealand
    Country flag
    I'm using a HDMI receiver for audio - even in this case all of the LAV audio the LAV audio bit streaming should be disabled?
    Depends if you want to prioritise video (ie. avoid dropped frames) or audio.
    If you want to prioritise audio you'd enable bitstreaming.
     

    Chananain

    New Member
    September 8, 2021
    1
    0
    Home Country
    United States of America United States of America
    Country flag
    Yeah, the problem was in hdmi cable version. My 6 years old full-hd tv shows a picture precisely as 4k tv when using an old hdmi cable. The bit rate throughput was not enough to render 4k videos correctly. Thankfully, noways cables are capable of dealing even with 8k60, even though less than 1% of people have such tv. However, I haven't spotted such a problem with 4k images. Despite the fact all my images are processed with an image sharpener, the data rate must be the same, so. Or, the image just loads slower. In the case of video, such slow loading would cause a "slow-motion" effect.
     
    Last edited:

    Users who are viewing this thread

    Similar threads

    MP1 MP2 MP2 DLNA status? DE
    What I meant is that we have a MP2 plugin called UPnP Render that can play media from DLNA servers if I remember correctly. I don't know the current state of the plugin though. That's why MP2 probably never will be certified. ;) Yes, that was also the idea, but it is a big job as all TV's, software etc. seems to not do everything...
    What I meant is that we have a MP2 plugin called UPnP Render that can play media from DLNA servers if I remember correctly. I don't...
    So I'm wondering what the state of play is with MP2 and DLNA functionality? When I started this post, I did see some posts...
    Replies
    10
    Views
    849
    It is looking and working very well now and I am almost at the point of switching my HTPC to MP2, madvr would definitely push me over the edge for sure.;)
    It is looking and working very well now and I am almost at the point of switching my HTPC to MP2, madvr would definitely push me...
    We are proud to present MediaPortal 2.3 MediaPortal 2.3 is a full-blown media center software that addresses the most common user...
    Replies
    4
    Views
    2K
    OK, this is specifically for people in Belgium (Vlaanderen) who are using Telenet Cable with MediaPortal 2. Next year (Edit: this year, in march 2020) the Telenet provider will stop broadcasting Analog TV and Radio signals on their cable, and make the switch to Digital (DVB-C). The radio signals will disappear completely, so you'll...
    OK, this is specifically for people in Belgium (Vlaanderen) who are using Telenet Cable with MediaPortal 2. Next year (Edit: this...
    OK, this is specifically for people in Belgium (Vlaanderen) who are using Telenet Cable with MediaPortal 2. Next year (Edit: this...
    Replies
    0
    Views
    865
    One of the few things that drove me insane with my switch to MP2 was the different picture and text quality (even from skin) for fanart and thumbs on my "living room" system compared to my Desktop PC. The images were fuzzy, sometimes pixelated or even blurred compared to the crispier versions on my desktop pc. I realized the only...
    One of the few things that drove me insane with my switch to MP2 was the different picture and text quality (even from skin) for...
    One of the few things that drove me insane with my switch to MP2 was the different picture and text quality (even from skin) for...
    Replies
    0
    Views
    690
    Hello I moved my timeshifting location to a separate partition and set the same access permission as the default location and Kodi was able to run live TV on all 3 client PC I was testing, Win7, Win10 and Ubuntu 16.04. The TV picture was steady and flawless on all 3 clients, even on the old Ubuntu laptop originally released for...
    Hello I moved my timeshifting location to a separate partition and set the same access permission as the default location and Kodi...
    Hello I was previously using MythTv using a Divico Fusion Dual Express PCIe and a Kworld Dual AF9015 which worked very well for...
    Replies
    17
    Views
    2K
    Top Bottom