Is this really as good as live-tv gets?!? (2 Viewers)

knutinh

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September 4, 2005
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If you see this thread (the best forum for figuring out PC to tv connection probs by the way):
http://forums.entechtaiwan.net/viewtopic.php?t=4325&highlight=samsung

One Samsung tv itselt is reporting to the graphics card that it will do (EDID info):

"Timing characteristics
VESA GTF support............ Not supported
Horizontal scan range....... 15-46kHz
Vertical scan range......... 59-61Hz
Video bandwidth............. 80MHz
Extension blocks............ 1
Timing recommendation #1.... 1920x540 at 60Hz
Modeline................ "1920x540" 74.250 1920 2008 2052 2200 540 542 547 562 +hsync +vsync
Timing recommendation #2.... 1920x1080 at 30Hz
Modeline................ "1920x1080" 74.250 1920 2008 2052 2200 1080 1084 1094 1124 interlace +hsync +vsync
Timing recommendation #3.... 1280x720 at 60Hz
Modeline................ "1280x720" 74.250 1280 1390 1430 1650 720 725 730 750 +hsync +vsync


Standard timings supported
640 x 480 at 60Hz - IBM VGA
1280 x 720 at 60Hz - Samsung
1920 x 540 at 60Hz - Samsung
1920 x 1080 at 30Hz - Samsung "


Now, you might be able to find other solutions using powerstrip (often, HD-ready specs arent even reported in EDID), but if youll soon return the tv I dont think it is worth ours and yours time.

Just tell your friends to shy away of Samsung if they will ever use a HTPC, and youll be fine =)

regards
Knut
 

MadDuke

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    For real - great !!! (proberbly not the 'normal' response!)

    -could you send a link?

    /MadDuke
     

    MadDuke

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    How did that post sneak in before mine?!?

    -doesn't matter! thanks for the info knutinh

    /MadDuke
     

    MadDuke

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    The ting is this only applies for one of the three 'primary errors' (Unsmoothnes) and some 'secondary errors'!

    These two ‘primary errors’; ’Pixel-bars’ and ‘Frame-stutters’ (read original post) are still a major bug!?! - can anyone help?

    /MadDuke
     

    knutinh

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    September 4, 2005
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    ’Pixel-bars’
    Ever so often there will be drawn a bar/line of ‘bad pixels’ across the screen, just for a fraction of a second but still totally unacceptable.
    Press "f11" when this happens and post the snapshot here. Sounds like it could be the result of very poor framerate-conversion somwhere along the line, where the outputframe is a mix of two frames, where the splitpoint is moving from top to bottom or opposite in a fast or slow motion. (writing to outputbuffer is not completed before it is read, so it contains leftovers from the previous frame)

    Try pressing "!" to get a scrolling bar to get a better impression.
    ‘Frame-stutters’
    Even worse is it when the picture momentarily freezes and then resumes very shortly afterwards
    (also a fraction of a second) it’s like the HTPC somehow ‘lost’ some frames!
    CPU-usage when this occurs?
    ‘UnSmooth’
    This has also improved greatly, but there is still a tendency for moving text, like in the bottom-line of CNN, or in movie credits to be ‘unsmooth’ and make ‘micro-stutters’ – this also applies for sports like in a football game!
    Clearly 50Hz vs 60Hz
    'OOS'
    Sometimes my picture is out-of-sync with the sound (or the otherway around!?!)
    Dunno.-. Try changing audio/video codecs, that my only choice.

    ‘Pixel-effect’
    It happens that the picture is somewhat ‘pixel-like’, eg. I can see ‘pixel-squares’ in waves in the see! – not that often though
    You are watching 576/2 lines of real information that is updated 50 times per second on a 1366x768 monitor updated at 60 frames per second. My best candidate is poor de-interlacing. Best seen around the edge of moving objects.
    ’Unsharp/blurry’
    The picture is not exactly super-sharp, but has improved greatly the last few day (earlier seemed a bit sharper, but was very ‘interlaced’) – It seems that there is a ‘blur-filter’ activated, and static boxes (e.g. ‘name-boxes’ seen on the news) have a slight vibrating effect (this has also been better earlier!) – But even though it is still a bit blurry/foggy I don’t know if you can expect more from DVB-S/T, I know I can’t expect ‘HD’ quality. But if it can be improved it would be nice.
    Basically, the de-interlace-scale process is not perfect, and never will be. You can hope to make it "less poor" though =)

    -k
     

    SpeedFreak

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    I have mostly the same configuration and have had similar problems.
    When I first installed MP (v0.2.0.4) I had terrible stutter, skip, lip synch, picture quality and stability (BSOD) problems. Now, several months later most of these problems are nearly gone. See this thread for a description of my woes.

    Unfortunately to get when I am now I have tweaked my system to the point where I don't know what worked and what didn't... I think MP 0.2.1 solved the stutter problem but it might have been something else as I believe I updated the video driver at the same time.

    One thing that did help me in the tuning process was the "!"-feature. Without it I would never have been able to identify that the stutter was caused by lost frames and excessive jitter.

    With my current configuration I lose zero frames and has minimal jitter. I do get an occasional skip but I believe that is due to disk contention (not that my disks are slow). The picture quality is perfect when I watch digital material (DVD, XviD, etc), but grainy, blurred and completely out of sync when I watch TV.

    I don't believe the argument that it isn't possible to get acceptable quality with "our" configuration. Yes, the source video is 50Hz and the TV only supports 60Hz. Yes, there is a difference in resolution and interlace. But... the TV itself doesn't seem to have the slightest problem with these conditions; The picture is perfect when I use the TV's own tuner, deinterlacer, scaler etc.

    If the TV can manage, then so should MP. The only real reason I can think of why my MP system can't compete with the TV on its own, is that the TV probably has a better tuner. Apart from the tuner, MP should be able to match all the TV's quality features in software.
     

    knutinh

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    With my current configuration I lose zero frames and has minimal jitter. I do get an occasional skip but I believe that is due to disk contention (not that my disks are slow). The picture quality is perfect when I watch digital material (DVD, XviD, etc), but grainy, blurred and completely out of sync when I watch TV.
    Could it be audio/video resync that is causing the slight frameloss that you are seeing? Audio and video are sent using local "clocks", while your soundcard and videocard has their own hardwareclocks. All man-made clocks drift, and when your soundcard clocks differ enough from the video clock, the code has to decide whether to skip video-frames, audio-frames, to loose lip-sync or risk emptying input-buffers.
    I don't believe the argument that it isn't possible to get acceptable quality with "our" configuration. Yes, the source video is 50Hz and the TV only supports 60Hz. Yes, there is a difference in resolution and interlace. But... the TV itself doesn't seem to have the slightest problem with these conditions; The picture is perfect when I use the TV's own tuner, deinterlacer, scaler etc.
    Are you shure that your tv does not support 50Hz when its intenalt tuner is used and receiving a PAL signal??
    If the TV can manage, then so should MP. The only real reason I can think of why my MP system can't compete with the TV on its own, is that the TV probably has a better tuner. Apart from the tuner, MP should be able to match all the TV's quality features in software.
    Given that the tv "gives" MediaPortal access to the same possibilities that it allows its internal tuner and that your PC tuner is of equal quality, then yes. MP cannot compensate for stupid tv-design though (such as crippling the PC input).

    -k
     

    MadDuke

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    I have made a few examples of the error ’Pixel-bar error’, you can see them here:

    http://www.malingkat.dk/screendumps/1.png
    http://www.malingkat.dk/screendumps/2.png
    http://www.malingkat.dk/screendumps/3.png
    http://www.malingkat.dk/screendumps/4.png
    http://www.malingkat.dk/screendumps/5.png

    The fifth one is not seen as often, but here the error sort of ‘moves with an object’.

    Remember, these errors are with the MPV codec, but I don’t have any ‘frame-loses’/’stuttering’ here (besides from the constant ‘micro-stuttering’)

    With the PureVideo codec I very rarely get the ’Pixel-bar error’, but with more or less the same frequency, I get the ‘frame-loses’/’stuttering’ – this seem to be connected!

    I wouldn’t say the CPU is hard pressed, sometimes is runs at 60-70 % for a period (dunno why!), but most of the time it is around 20-30 %. And there is no clear pattern between this and the errors.

    Most of the time the ‘False VMR9’ is at 50 (or very close to), but when there is a stutter it drops dramatically down to eg. 30, 20 or even 10 for a short period, and then up again, other times is drops to 25 and says there for a while.

    I’m wondering, what does this ‘False’ indicate ? (it sounds a bit alarming!)

    Typically there is a ‘single stutter’ within the first 2 sec (on both codecs), when you change the channel, but I figure this is ‘normal’!

    I’m thinking that I should test the TVEngineV3 – any comments on that?

    I must say that I don’t get the thing about the resolution – I mean, according to you there shouldn’t really be a problem setting it at a resolution with 50hz – I just can’t make it work!?!

    /MadDuke
     

    Spragleknas

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    This definetly is not my table, but:
    OOS: Make sure to use Default DirectSound Renderer for Audio renderer (dunno why, but I read it somwhere and it seem to work).

    And: Don't play with a toy your not gonna have for long; esp. when it does not cover your needs.... when you get back to using your CRT, have a look here:
    Using Standard Definition Native Resolution for MediaPortal
     

    tourettes

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    Those pixel bar errors are caused by errors in the DVB stream. Different codecs react differently to those (as you have seen). Some codecs will display garbage and some others will drop frames.
     

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