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digital video - monitors & televisions


[tech] article date: October 2006
[ - ]

See also : tech\shopping\projectors_tv.html

 

from http://www.learningcenter.sony.us/article/HomeAudioandVideo/Televisions/Research/UnlockingtheCodetoHDTV :

Quality televisions have extremely competent scalers so you needn't worry too much about seeing scaling-related artifacts. That being said, a display will typically perform its best when fed a signal which matches its own native resolution.

 
A true HDTV is at least 720p native (meaning it has at least 720 horizontal scan lines, scanned progressively).  

Example: Sony Trinitron multiscan E540

A true HDTV is at least 720p native, meaning it has at least 720 horizontal scan lines, scanned progressively.

  • progressive
  • 75 Hz
  • connection type:
  • 1280 x 960
  • 16:9 wide-screen video mode: 1280 x 768 ~~ 720p* reso = 1280 x 720 (1280/720=1.78)
  • wide-screen, academy flat, video mode: 888 x 480 (888/480=1.85) or 1332 x 720 or 1280 x 691.9

 

...

?

1920 / 1080 (1080 interlaced) = 1.78 = 1.78:1 = 16x9 = 16:9 :

If a television has a native resolution of 1920 x 1080, this means its pixel grid is comprised of 1920 pixels across and 1080 up and down. If you divide 1920 by 1080, you'll get (wait for it) 1.78 - the standard aspect ratio for widescreen displays.
 

 

If a TV accepts 720p and 1080i, does that make it a HDTV?


No. There are many "Enhanced Definition" TVs (EDTV) available with a native resolution of 480p.
EDTV's can usually accept a 720p or 1080i signal but will scale the image down to 480p.
A true HDTV is at least 720p native, meaning it has at least 720 horizontal scan lines, scanned progressively.
A Full HD 1080p display has the potential to deliver the highest HDTV resolution available.

 

Sony Marketing Term 1: CineMotion Inverse 3:2 Pulldown: using the reverse 3-2 pull down technology, the Cinemotion feature provides smoother picture movement when playing back movies or other video sources

What it means:

2-3 pulldown - The process of converting 24-frame-per-second film to video by repeating one film frame as three fields, then the next film frame as two fields.

3-2 pulldown - An uncommon variation of 2-3 pulldown, where the first film frame is repeated for 3 fields instead of two. Most people, when they say "3-2 pulldown", actually mean 2-3 pulldown.

Progressive scan DVD players and line doublers convert interlaced video to progressive video.
[read more/details/source]

Film goes to video (interlaced) as 3 fields followed by 2 fields followed by 3 fields followed by 2 fields (3:2).
This process is called "Telecine" (24 frames of film become 30 frames of video).

When a film source is encoded for presentation on DVD, it is stored at 24 frames per second; each video frame contains all the picture information from each film frame. There is no redundancy or duplication. Such a transfer is written to DVD as 720-pixel wide by 480-pixel high interlaced frames (where each frame contains two 720 by 240 fields), and there are only 24 frames for each second of film. This is known as 480i24. On each DVD encoded from a film source, a flag is inserted within the MPEG-2 data stream that instructs the player to repeat certain fields to reconstruct the 29.97 frame per second interlaced video. The devices obliges by performing the 3:2 pulldown in real-time, continually creating interlaced frame sequences.

 

 


Belkin Digital Video Dual-Link Cable with Tinned OFC Conductors

 

So for standard users the signal you are getting into your tv:

from DVRs = interlaced
from VCRs = interlaced
from DVD players = progressive source, converted to interlace frames (???), 720-pixel wide by 480-pixel high

from a pc, signal is usually progressive. But, depending on your output card, you can customize the signal to 30 Hz, interlaced, 720 x 480.

from my pc: an interlaced signal played through a progressive signal, 720x480

BlueRay is 1080p

 

DRC-MF (Digital Reality Creation Multi Function Circuitry) replaces an analog signal's NTSC waveform with the near-HD equivalent. The result is an image with four times the picture density

 

Upconversion (analog)

Reportedly, the Sony STR-DE998 A/V receiver (summer 2005) will "upconvert composite and S-Video inputs to component video."
But this really only means that it will "transcode" your s-video or composite input signal to a component output signal.

It's not really an advantage; it's just a way to allow older inputs into an A/V receiver to be output via newer connections (i.e. a single cable).

* 7.1-channel A/V receiver; SACD/DVD-Audio inputs; "If your TV has a component-video input, you'll need to run only one set of cables from the DE998; the receiver will upconvert your VCR or cable box's composite or S-Video outputs to component video. "

"[QUOTE=CORVETTEZ06]My Marantz SR7500 came with a main feature of "Component upconversion with TBC". Does that just mean that svideo inputs are upconverted to component ][/QUOTE]

The TBC part of it, is so you can upconvert/transcode from a VCR composite or SVHS signal up to a component output, without "hopefully" having any adverse video issues (such as picture noise, screen blanking, etc) in the process. It will not scale, improve or increase the resolution of the VCR source material in any way. At best it will look just as good as if the VCR was hooked up direct to the TV itself, or it can even be a little worse. But without TBC, VCR transcoding to component outputs, can often end up being totaly unwatchable. "

 

 

 

Composite Video

see comparison of composite / s-video / componentHigh-Performance, Digital Video Dual-Link Cable with Tinned OFC Conductors for High-Accuracy, Natural Sound Quality.

 

other types:

"Digital Outs"

See also "TosLink Fiber Optic Audio Cables" (Optical Out)

i.link / Firewire / i1384 / IEEE 1394

From FAQ: Q: How fast is 1394?
A: The 1394 standard defines three signaling rates which, in precise terms, are: 98.304, 196.608 and 393.216 Mbits/s (megabits per second).



Example: the DENON DVD-3910 DVD & SACD Player :

Denon DVD 3910 Connection Table
  AUDIO VIDEO
  Analogue Digital Analogue Digital
 
Line

Optical

Coaxial

i-link

Component

S-Video

Composite

SCART

HDMI

DVI-D
Outputs 1+5.1 1 1 1 1 1 1 1 (RGB) 1 1

[back to article]

The maximum physical display resolution of the external monitor is 640 × 480 dots when the aspect ratio is set to 4:3, and 852 × 480 dots when the ratio is set to 16:9.

Example: An advertisement for a Widescreen LCD TV lists "Component, S-Video, composite, and 15-pin D-sub inputs"
This would mean your best connection from a DVD player would probably be the Component input, and your connection from a PC would be the VGA (15-pin D-Sub RGB) input.

Note: "A/V cable" (audio/video) cable is too generic: it could be an HDMI A/V cable, component A/V cable, Composite (yellow-red-white) A/V Cable (*), etc.

*note: This link is a pop-up. Not all popups are evil. Deal with it.

  


  
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Last Updated: November 13, 2004
Minor Modifications: March 2005, Oct 2005