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Is there a chip on the market which can overlay one HDMI-input over another ?

Chip should have 2 * HDMI -IN and 1 * HDMI-OUT

HDMI-IN-1 connected with Sat-receiver or other TV-Source HDMI-IN-2 connected with Android-Box or Network Player

The Menues of HDMI-2 shall be superimposed/blended/overlayed over TV-Screen of HDMI-1. e.g. by replacing the black background color of Android-Screen with TV-Screen-Pixel.

If superimposing is not available a splitscreen function would be sufficient, e.g. upper or lower part of HDMI-OUT reserved for HDMI-2 IN and rest for HDMI 1 in.

Brian Carlton
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Guido
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    http://wiki.chumby.com/index.php/What_is_NeTV (I know this isn't an answer, and barely qualifies as a comment, but it should help OP in some fashion) – dext0rb Jul 03 '12 at 00:53
  • HTML-input or HDMI-input? ;-) – avra Jul 03 '12 at 08:37
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    Do you want this to work with encrypted HDMI? In which case this is going to be quite a project .. – pjc50 Jul 04 '12 at 15:28
  • Don't ask for product recommendations here http://meta.stackexchange.com/questions/158809/why-are-shopping-list-questions-bad pose your question as a design question. – Voltage Spike Jan 09 '17 at 17:20

3 Answers3

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I do NOT think there is a single chip solution neither. However doing this with an FPGA-based platform is certainly doable. As already mentioned the Digilent Atlys Board could be an alternative since you have there 2 in/ 2 out HDMI ports.

In case you consider working with FPGAs:

First, I would suggest to start with the design of a HDMI transmitter and receiver. There is another question that gives a good starting point. Then, the overlay can be achieved with an HDL- implementation of the alpha-blending algorithm which can be used for mixing 2 images into one. The good point is that this gives you the possibility to configure the level of transparency of individual picture elements.

In few words: being x and y the inputs and z the output video signal. An alpha-blender circuit can mix them implementing the equation:

z = x.(alpha) + y (1-alpha); where "alpha" is the coefficient or level of blending.

Finally, you can integrate the previous blocks making the following processing chain: HDMI receivers -> overlay logic -> HDMI transmitter.

I hope this helps!

L30nardo SV.
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The simple answer is "no, there is no single-chip solution." The reasons are already mentioned by Chris Stratton: - The two signals are not in sync, so at least one of the frames need to be re-buffered (typically, both will need to be, to be able to do the blend/overlay.) - HDMI in a living room typically carries encrypted signals, so you need to also do HDMI content protection negotiation. - The resolutions may be different.

Additionally: - HDMI is a pretty high data rate signal, especially if you go above ATSC to 1080p60/30-bit etc. That's half a gigabyte per second per stream direction, so to capture two streams, then read/sum two streams, then output one stream, you end up with 2.5 GB/s in pure data traffic (and more for overhead.)

None of this is impossible. Broadcast video equipment does similar things just fine. But it's a cost question.

Actually, I did a digikey search, and this chip came up: Analog Devices ADV8003 http://www.analog.com/static/imported-files/data_sheets/ADV8003.pdf

At $70 it's not super cheap, and the datasheet is ludicrously empty (doesn't even specify a chip form factor,) so you'd have to work with AD application engineers to actually get anything done with it. And it doesn't do the actual HDMI capture; you have to do that using separate chips. But it's the closest that a simple search could find.

Jon Watte
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Two HDMI receivers, an HDMI transmitter and an FPGA+some memory would do it. But that's 4 chips, sorry :(

I thought this bunch used to have a "two-HDMI-in one-out" box, but it appears not.

You might try Googling "HDMI video mixer" or some such combination.

Martin Thompson
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  • This is the board you want: http://www.digilentinc.com/Products/Detail.cfm?NavPath=2,400,836&Prod=ATLYS – drxzcl Aug 03 '12 at 10:51
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    Even unencrypted this will be tricky, as there are multiple resolutions possible, and even when the resolutions are the same the scan rates won't be synchronized or even perfectly matched. But it should be possible - I've seen commercial products which mix audio into an HD-SDI stream (comparable professional studio interface), presumably video mixers exist as well. – Chris Stratton Dec 01 '12 at 20:17