Brain teaser: Would 300 Hz TV solve the European - US compatibility problem?

Working on defeating that Mantis... The question: how to display a 50Hz camera on a 60 Hz monitor, without any frame skipping, and without large frame stores (say memory). So 50 Hz versus 60 Hz, The first common product is 300. Refresh rates are going up all the time on LCDs...

Solution: A LCD with 300 Hz V sync.

How about it?

Reply to
Jan Panteltje
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I'm not sure I understand what you eventually want to do! Also, color or monochrome? If you just want to 'display' why not an NTSC/PAL compatible monitor?

Reply to
PeterD

Jan Panteltje a écrit :

No, it's 150.

Get a 200Hz one and trash one frame out of 4?

Or repeat one frame out of six? Wonder what visual effect this could do? You can probably test this on your PC by substituting every fifth image with the preceding one...

--
Thanks,
Fred.
Reply to
Fred Bartoli

On a sunny day (Mon, 21 Sep 2009 08:34:42 -0400) it happened PeterD wrote in :

Color of course. There are a number of issues. As to NTSC/PAL compatible monitor, those are disappearing from the market here. I could only find ONE LCD monitor, an Asus LCD, and it was more expensive then normal. This because all is digital I guess. Most PC monitors are now specified at about 56 to 75Hz for LCD. This makes it impossible for example to use a line doubler to convert PAL camera output (50 fps / 15625 Hz) to 50 fps / 32 kHz, as the monitor will croak at 50Hz. These doublers allow for simple circuits as they only need one picture line of memory. In any other case you will have to drop frames every so often. Not a big deal with normal video, but a HUGE deal when using LCD shutters, becomes easily very noticeable.

Reply to
Jan Panteltje

On a sunny day (Mon, 21 Sep 2009 15:13:59 +0200) it happened Fred Bartoli wrote in :

There are many ways, but for 3D display with shutter glasses everything becomes much more visible, or say annoying if it is not a 1 to 1 ratio. A high frame speed and no dropped frames helps a lot.

3D will invade the living rooms in the next years.

I am actually wondering if the new 3D material will be produced as 24 fps movies, or they got smart and use 25 / 50, it is all electonics anyways, no more film / telecine. Or 25 and 30 (50 / 60) in tha tcae 300 Hz woul solev most problems for 3D too.

Reply to
Jan Panteltje

PAL vs NTSC chroma usually hurts more. There are various cheap consumer boxes available to handle multistandard TV video signal convertions - a lot of Japanese kit will do it out of the box although you may need to unlock this functionality. Most of the stuff sold in Akihabara is fully unlocked to be global multistandard in every possible permutation.

Expensive way of solving the problem with higher datarates. Dunno if these guys product is any good but it probably does what you want.

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Regards, Martin Brown

Reply to
Martin Brown

On a sunny day (Mon, 21 Sep 2009 14:47:38 +0100) it happened Martin Brown wrote in :

Interesting device, that is exactly the frame store solution. This means you are short 10 frames at 50 Hz input after one second, if your TV or monitor is 60 Hz. This is fixed in the that device by repeating frames. Or dropping frames if going from 60 to 50 Hz.

The solution I propose, is using a 300 Hz monitor would display 5 30 fps frames, or 6 50 Hz frames, per second without any frame drops. Frame drops, and repeated frames, are very annoying on _horizontally_ moving objects, those just seem to jump irregularly from left to right, or right to left. In case of 3D, where left / right eye is displayed sequentially, the effective frame rate seems lower, and the effect is even more annoying.

Higher data rates, that must be a joke right? The idiots are using HDMI serial with gigabit data rates for HD, so they are used to it :-) If they can sprinkle that much on datarates for copy protection, sure for some display improvement it should be no problem.

Reply to
Jan Panteltje

Why not just let it roll vertically at 10 fps? There's nothing worth watching on there anyway.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal
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Reply to
Phil Hobbs

I'm working on new circuits, under the Mantis.

Digital displays are almost always frame buffered, interpolated, enhanced, edge processed, decompressed, all that. There's usually no relationship between the incoming frame rate and the display refresh rate. It doesn't matter any more.

US broadcast TV is/was 30 fps interlaced, and looks great on a 70 Hz LCD.

John

Reply to
John Larkin

On a sunny day (Mon, 21 Sep 2009 08:49:37 -0700) it happened John Larkin wrote in :

Only for viewers content with low quality :-)

Well, some time ago I went to the shop for a large LCD TV (not monitor). there were many 60 Hz versions, and some 50 Hz. I stood there and watched them all on for a while. The 60 Hz versions were useless as the picture jumped on any horizontal movement. Many however bought the things it seems.

Recently I have been experimenting with it here, and I can tell you that there is a world of difference in picture quality (in the sense of display of material with motion in it).

I use the latest Nvidia (beta) drivers with open GL, a lot of interesting options are available, look here for example:

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You can easily test for differences. Now, with 3D coming, this is ever so much more important.

300 fps frame rate is not even that much, gamers would love it.

A lot of good common sense TV knowhow went out of the window, and quality with it, when digital came, remember that mpeg2 and friends are all lossy compressions, the whole transmission chain had a huge latency, and generally quality is sacrificed. (Among other things for more programs in the same bandwidth).

But then many people have no clue how even to adjust their TV set in the US, probably a left over from the NTSC (Never Twice Same Color) era, so I guess that, and you getting old and blind perhaps, could explain why it does not bother you. Then there is that interlace - deinterlace issue. De-interlace never works. But you did not notice? Ooops.

Reply to
Jan Panteltje

On a sunny day (Mon, 21 Sep 2009 11:42:15 -0400) it happened Phil Hobbs wrote in :

A good idea, I can pipe the stream to /dev/zero too, but I am experimenting with my own cameras and 3D, so how would I learn?

Reply to
Jan Panteltje

objects,

frame rate

Well, that display of five (or six) frames per source frame is fine but you'd still have to store a frame to (re)display it the five (or six) times, right?

I'm not sure you'd get any magical benefits over any other, commerciallly available system myself.

Reply to
PeterD

Practically all television is low quality.

movement.

Car crashes? Kung-fu battles? Gunfights? Video games?

it,

that,

Everybody is getting old, and my vision is a bad as it's always been. And you are being a jerk.

My big-screen TVs and my computer monitors are fine visually. The problem with TV isn't technology, it's content. All we watch is DVDs and the occasional PBS "Mystery" show, which are themselves getting progressively stupid. Last night's Inspector Lewis was absurd.

It always works. Why wouldn't it?

If the picture looks fine to me, why should I make an effort to learn to dislike it? It's like becoming a wine snob: all it does is make you spend more money for wine and enjoy it less.

Get a life and unplug yourself from manufactured entertainment. I can recommend some good books.

John

Reply to
John Larkin

On a sunny day (Mon, 21 Sep 2009 10:17:19 -0700) it happened John Larkin wrote in :

Well, *is* is an opinion, in this case *yours*, so should be evaluated in that context. I actually enjoy some high quality content, when it is broadcast.

movement.

Actually more like cartoons where it really showed even for the near blind ;;;;----)))).

that,

Wow, you felt offended? Still that perfection complex? LOL

Na, personal opinion, no science. I was talking about hardware, that IS science. Software too.

I have a box with more then 700 DVDs in the attic. All content is now on harddisks. It streams in from various sources, satellite, the internet.

OK You are just babbling, really have no clue, try reading something by an other expert if you do not believe me:

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Na, it is like drinking polluted Frisco water every day. You get used to it, get blind, see no longer anything.

Reply to
Jan Panteltje

On a sunny day (Mon, 21 Sep 2009 12:42:32 -0400) it happened PeterD wrote in :

frames,

objects,

frame rate

Right.

No motion jerking.

Reply to
Jan Panteltje

You just haven't seen the right kung fu battles. ;-)

Rent "Curse of the Golden Flower" and put the popcorn on.

--
Rich Webb     Norfolk, VA
Reply to
Rich Webb

The San Francisco water comes from the Hetch Hetchy reservoir in the Sierras. It's melted snow. It's better than just about any bottled water you can buy, absolutely better than any packaged in plastic.

The water arrives from the Sierras at the Pulgas Water Temple about a half-hour south of here and then runs through a sluce into the Crystal Springs Resevoir, a chain of subduction lakes that follow the San Andreas fault. It's all very, very beautiful... provided you turn off your TV and get out and see it.

Where does your water come from? Can you drink the tap water?

On a clear day, I can see the snow on the Sierras, clear across the state, 180 miles away.

You snipped the part about books vs manufactured video crap. Read any good books lately?

John

Reply to
John Larkin

How are the fake sound effects?

John

Reply to
John Larkin

Unnoticeable. Seriously, it's quite a beautiful film.

--
Rich Webb     Norfolk, VA
Reply to
Rich Webb

In some past olympics, 300 fps has been used in the slow motion cameras e.g. for 100 m track and field or ski jumping. In both cases, the actual performance is below 15 s, so buffering the signal at the camera is sufficient (RAM). The readout can be at standard 25 or 30 fps frame rates.

As long as you have sufficient illumination, 300 fps is not a huge rate.

Doing it at low illumination levels, you really have to think how many photons will hit a pixel in a frame and in a specific wavelength band.

Paul

Reply to
Paul Keinanen

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