how does software know if your tv is active or passive?

[goemon]

when you watch a 3d film on tv using a digital cable box, how does it know if your tv is an active shutter type or a passive polarized type? it should matter because both formats work different right? or how about when watching a blu ray movie?

what about on a playstation 3, is there a way to tell the system what type of tv you have so it knows how to display the 3d images properly?

[ShawmK]

It doesn't matter to the 3D source whether the television is active or passive; both can accept the same signal.

In the same way, it doesn't matter to a DVD player whether a television is LCD, OLED or CRT - they will all display the image just fine.

[goemon]

but how is that possible? active 3d alternates images for the left and right eye rapidly, but passive 3d displays images for both eyes simultaneously and lets the glasses take care of the work of separating the images to each eye and it also drops the resolution by half, so they work different and should display a different type of image. is it the case that the 3d data is encoded, and then depending on the type of 3d tv you own, the 3d tv decodes it and processes it differently depending on its type?

[Likay]

Active tv-sets provides the glasses with their signal, not the source (like computer, consoles etc). As you say the tv of course separates and decodes the images differently depending on the sourcesignal side-by-side, checkerboard, hdmi1.4fp etc etc.
Therefore an active 3d-tv comes with its own set of shutterglasses.

[goemon]

" As you say the tv of course separates and decodes the images differently depending on the sourcesignal side-by-side, checkerboard, hdmi1.4fp etc etc."

the interesting part is when you say "decodes the images differently depending on the sourcesignal". so the source signal can be checkerboard, side by side, etc. so how does the ps3 know what to make the source signal? the ps3 has to determine the format, or all 3d data is universally encoded in the same way whether the originating hardware is a cable box, ps3, nvidia geforce, etc., then the display decodes the 3d data?

[AntiCatalyst]

That's standardized in the latest HDMI versions(1.4 and up). a 3d signal is sent out in a certain way, and it's up to the monitor to decode it.

There are also manual modes where you basically just tell the TV what format you are sending to it. This is used if the source isn't HDMI 1.4 compliant.

[cybereality]

The software doesn't have to know. It just sends both full quality views (left and right) via HDMI 1.4a and the display itself decides what to do with it. So it could be an active display using page-flipping, and passive display using interleaved, or even an HMD with two separate LCDs. It doesn't matter. That is why it is pretty dumb when bloggers compare active/passive to the HD-DVD/Blu-Ray debacle. Its not a format war, any more than LCD is at war with Plasma, or DLP, or OLED, etc.

[goemon]

thanks everyone for making this make sense now