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  1. From the Westinghouse website @ http://www.westinghousedigital.com/pc-52-2-32-lcd-hdtv.aspx

    Progressive Scan, I know what that is
    Aspect Ratio Conversion, ?
    CCS (Cross Color Suppressor), ?
    3D Noise Reduction, Regular Noise reduction I know but 3D?
    Inverse 3:2 pulldown, ?, Their website says a technology which correctly reconstructs movie films for display on a digital video device for film at 24fps and digital video displayed 60fps....I understand the pulldown concept for fim to 29.97fps on a regular TV but whay do it to a 60fps disgital?
    3D Video Processing, 3D?
    3D Comb Filter, Comb Filter I know but 3D Comb Filter?


    I'm happy with the picture, Now I just need to wrap my head around some of the concepts such as the way the hd channels are numbered and what it means.

    Thanks
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  2. Member edDV's Avatar
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    Originally Posted by TBoneit
    From the Westinghouse website @ http://www.westinghousedigital.com/pc-52-2-32-lcd-hdtv.aspx

    Progressive Scan, I know what that is
    Aspect Ratio Conversion, ?
    The LCD display is a fixed 1366x768 resolution which is square pixel 16:9. 480i and 480p are 720x480 (non square pixel) for 4:3 and 16:9. "Aspect Ratio Conversion" converts it all (plus analog) to the 1366x768 screen giving the user choices of pillar boxes or stretch for 4:3 display.

    Originally Posted by TBoneit
    CCS (Cross Color Suppressor), ?
    That is the residual subcarrier noise from analog Y/C separation (e.g. dot crawl and moire noise).

    Originally Posted by TBoneit
    3D Noise Reduction, Regular Noise reduction I know but 3D?
    Inverse 3:2 pulldown, ?,
    Digital noise reduction can take place over x, y (in frame) and t (historical frames) by using line, field or frame memory. Fancy noise reducers will use motion detection to maximize noise reduction in low motion areas, and limit noise reduction in motion areas (which would cause smear).

    Originally Posted by TBoneit
    Their website says a technology which correctly reconstructs movie films for display on a digital video device for film at 24fps and digital video displayed 60fps....I understand the pulldown concept for fim to 29.97fps on a regular TV but whay do it to a 60fps disgital?
    Normal 480i/29.97 (or 1080i/29.97) uses the telecine field repeat process to convert 24p to 29.97i.

    Since the LCD panel is native progressive, it is desirable to convert telecined film source 480i back to 480p/23.976 progressive to improve display quality. This process is called inverse telecine or IVTC.

    If 24 fps were displayed directly, it would flicker like crazy. So what is done in HDTV sets and progressive DVD players is a frame repeat to 59.94fps. This is done by repeating alternate frames 2x, then 3x, then 2x and so on. Do the math, that works out to a 23.976 to 59.94 frame rate conversion. Using these techniques all sources (analog NTSC, 480i, 720p and 1080i) are displayed with 59.94 refresh.
    http://www.dvdfile.com/news/special_report/production_a_z/3_2_pulldown.htm

    In PAL areas, 576i and 1080i are displayed at 50Hz refresh (sometimes doubled to 100Hz).

    Originally Posted by TBoneit
    3D Video Processing, 3D?
    X, Y and t again. That is, historical information is used such as motion detection and line, field or frame storage.

    Originally Posted by TBoneit
    3D Comb Filter, Comb Filter I know but 3D Comb Filter?
    Digital 3D comb filters work in 3D color space (YUV or RGB) to separate Y from C (UV).

    http://members.aol.com/ajaynejr/vidcomb.htm
    http://en.wikipedia.org/wiki/Comb_filter


    What do you mean by "the way the hd channels are numbered"?
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  3. I thought that 3D comb filters worked by cleaning up the current frame by using data from surrounding frames. Boy do I feel stupid!


    Darryl
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  4. Guilty here too, I though comb filter( As in communication channelisation) was used to get a cleaner TV station signal.

    Also, read digital audio folks call comb filters a basic building block in sound effect ?

    How many kind of comb filters are out there ?
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  5. Member edDV's Avatar
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    Originally Posted by dphirschler
    I thought that 3D comb filters worked by cleaning up the current frame by using data from surrounding frames. Boy do I feel stupid!


    Darryl
    The fancy ones adapt modes using motion detection (historical line field or frame data) so that applies too.
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  6. Member edDV's Avatar
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    Originally Posted by SingSing
    Guilty here too, I though comb filter( As in communication channelisation) was used to get a cleaner TV station signal.

    Also, read digital audio folks call comb filters a basic building block in sound effect ?

    How many kind of comb filters are out there ?
    That Ajay Nejr link gives detail on all types of notch and comb filters.

    Analog comb filters use delay lines (one to three lines or more) to apply phase cancellation.
    Digital comb filters work in 2D (XY analysis for composite to YC) or 3D (XY analysis for composite to YC + motion adaptive mode switching).

    Turns out there are several 3D techniques some of which use historical composite picture data, others use motion detection to switch 2D modes based on motion. I shouldn't have said YUV space, it is actually closer to filter mode switching based on XY picture change analysis + frame to frame motion analysis.

    Better to read the link. It gets complex.
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  7. Thnaks edDV for the explanations, Your knowledge is encycolpedic when it comes to video.

    As to the HD Channels they can have more than one stream in the channel as I understand it? Thus if I tune to a dt channel do they all start with a channel number and then go from there? I hooked up my basic cable feed to the TV and if I tune to channel 721 it shows as 721--2 then that changes to 721 480i stereo etc.

    Which also as I understand is really SD signal?

    Cheers
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