Electronics > Projects, Designs, and Technical Stuff
Progressive to Interlaced Converter
<< < (4/5) > >>
Miyuki:
VGA cards used to support interlaced output on vga port
It was just matter of drivers and commonly not user friendly accesible config to se those modes
T3sl4co1l:
Yeah, it's twice the bandwidth so you have to lose data.  Pulling down every other (you'd still need a line's worth of storage to resample it) is about all you can do.

There are refinements of course, like capturing consecutive frames and filtering them, alternating which lines are pulled down.  The same deinterlace filters that are used for capturing video, work the same in reverse as antialiasing filters.

Tim
paul_g_787:
Another way of looking at this.

I have this cheap device from ebay. It takes HDMI in and outputs composite video / stereo audio. It works great but composite video quality is utter is bullsh*t and I cannot read the text on the screen.

https://www.ebay.co.uk/itm/1080P-HDMI-To-SCART-Composite-Video-Scaler-Converter-Audio-Adapter-for-DVD-SKY-/202568495043?_trksid=p2349526.m4383.l10137.c10&nordt=true&rt=nc&orig_cvip=true


There are two ICs inside. One right next to the HDMI which is a  CM6616A and I cannot find a datasheet for this but if I had to guess, it is a HDMI to RGB chip perhaps?

This second IC is a MS1835. I cannot find a pin-out for this IC but have a look at the block diagram on their website:
http://en.macrosilicon.com/info.asp?base_id=2&third_id=17

Now it does not appear that this IC has RGB out, only composite or S video out. Unfortunately they haven't even wired in the S video on the device as I only get a black and white image when trying it on the TV.

I am unsure if there is a way this device can be modified to output RGB.
I am wondering what would happen if I connected the RGB input pins to the RGB pins on the SCART output. would this be possible?

Is anyone able to find the full datasheet for this MS1835?

Surely there must be another IC similar to this out there, a video encoder that that can take the RGB from a PC and output RGBS with a 15.625KHz output for PAL?

paul_g_787:

--- Quote from: james_s on October 16, 2019, 04:10:07 pm ---You used to be able to get VGA to TV converter boxes for around $25, can you not still get those? Some PC video cards can be tweaked to produce nonstandard timing too. Another option is a Raspberri Pi, it has a composite output and a Kodi client.

--- End quote ---

Yes you can still get those but they, like the raspberry pi are only composite which is absolutely disgusting on the screen and the text is so blurry it is almost unreadable.

Now if there was one of these VGA to TV converters that simply output the RGB and sync signals seperately before they are combined into composite then this would give a perfectly good image via RGB SCART and would be exactly what I am looking for.
Benta:
What you need to realise is, that 95% of commercial European TVs do not have RGB inputs*. Check the repair schematics.
The SCART specification is wonderful, but almost always implemented as CBVS input (and output) only.

Your blurred text problem is because you expect VGA resolution from a bandwidth limited analogue video signal, RGB or CVBS both. It just won't work.

(*) we're still better off than in the US, where they have no SCART inputs at all.
Navigation
Message Index
Next page
Previous page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod