Video Out Broadcast - any ideas from serious tech guys and gals

[willir]

I am trying to "fix" somebody else's problem -- very poor resolution and lack of clarity on reception end of video projection. I am looking for suggestions on a better video card, configuration changes, third party software suggestions or tweaks.

We have a workstation that is used as a "master" -- it connects to RF (radio frequency) digital broadcast equipment. The broadcast signal is picked up by antennas through out the fascilities, and is connected to LCD TV's via coaxle cable.

The equipment is not ideal.

HP workstation has an nVidia Quadro NVS 280. It has an S-video analog port. This connects to a Y-RW composit connection on the broadcast equipment.

On the receiving side,the coaxle cable plugs into the coaxle port on a Sharpe Aquoos LC32 D62U (spelling mistakes are intentional).

I am stuck with the broadcast equipment limitation - YRW (Y - analog video, R and W audio), the antennas with the coaxle connection and the LCD TVs.

I can change the video card. Any suggestions??

I have played with several things -- drivers, some improvement, tweaks to the Jpeg and Mpeg files, tweaks to the TV settings -- but still pretty poor quality.

Image lacks resolution and clarity, and the refresh is very blocky. Images and graphics look much better than text -- text is unreadable. Refresh fixed at 60 Hz, image resolution at 1024x768 (max setting) -- reducing resolution does not help.

TV work well with regualr broadcast, and the images are amazing with the DVI to HDMI connection. Image files are of good quality.

Thanks in advance.
Richard

 

[Nelviticus]

What resolution are you using? Composite video can only carry an NTSC, PAL or SECAM video signal, all of which are interlaced and have about 500 lines so if you're trying to display a 1280 x 1024 PC image (for example) it's going to look pretty awful.

Lower resolutions tend to fare better and the nVidia drivers have some options you can tweak to improve things, although I've only ever used them with GeForce-series cards and not Quadro. If I remember correctly there is a setting where you can choose S-Video or composite output - choosing the wrong one here will make the display black & white and extremely grainy.

Sorry there's not much concrete info in my post but hopefully there's something useful!

Regards

Nelviticus

 

[kestrel1]

Have you tried a signal booster from the coax side of things.
I am probably barking up the totally wrong tree, but hey ho.

 

[felixc]

As Nelveticus said, TV resolution is low and interlaced. You are likely to have flicker issues with the edges of computer-generated images.

To isolate things, what is the quality of the image when you connect one of these TVs directly at the video out of the PC?

 

[willir]

Sorry about not getting back to everyone -- was pulled off on another project.

TV
- using NTSC
- capable of supporting 1080P / 1920x1080
- digital coax input

TV end of things:
The biggest problem is the quality of the image being sent to the TV or broadcast system, and not on the TV receiving end.

Current video card
- max resolution is 1024x768

Video Image quality
Have tried various quality images, i.e. 160x112 to 400x300, mpeg, always looks poor. Note: With a digital graphics card to HDMI connection on the TV, the quality is fantastic, but I have to use the broadcast over a the YRW analog connection. The image quality seems to be sufficient.

We will be looking at the Matrox Parhelia -- more pricy than the nVidia Quad NVS 280, but seems more suited to the task.

Thanks for your replies so far.

 

[Nelviticus]

I can't quite figure out what the set-up is but it sounds as though it boils down to a PC outputting its display to a video broadcasting system with a bunch of LCD TV's then picking up the signal.

If so, I think you may have more luck on a dedicated video broadcasting forum as your question is really "what's the best way of using a PC to generate a broadcast-quality video output."

I suspect the weakest point in your chain is the PC's output to the broadcast equipment. I've no idea what the ideal method is but I'm sure it's not S-video.

Regards

Nelviticus