Quote:
Hi Gideon,
The HDMI standard provides backward compatibility for DVI signals so you can
use and adapter on a DVI port to output to a HDMI display.
However DVI computer monitors expect 8-bit RGB signals, and DVI signals are
always 8-bit RGB. HDMI signals are most commonly 8-bit YUV but could also be
RGB and could also be 10 or 12-bit in the latest HDMI 1.3 specification.
We are currently unaware of any cameras or DVD players which output anything
other than 8-bit YUV through their HDMI port. If you were to attach a simple
HDMI-to-DVI cable to these devices, they would fail to work with a DVI
display.
Furthermore, DVI computer displays typically work at one frequency which is
usually 60 Hz. This contrasts with NTSC and PAL signals which are 29.97 and
25 Hz respectively and are therefore incompatible with DVI computer displays
although they should work with DVI TV's which support multiple frequencies.
In order to guarantee that a HDMI signal can be displayed on a DVI computer
monitor, such as an Apple 23" or Dell 24" display, the signal would need to
undergo colorspace conversion from YUV to RGB and then pulldown processing
would need to be performed on the video frame rate to adapt it to the 60 Hz
rate expected by the display. If the HDMI signal was anything other than
8-bit, it would also need to be adapted to 8-bit. I'm sure there are
probably expensive convertors which do this but it would make more sense
just to use a HDMI display which supports multiple frequencies.
DVI does not support audio. HDMI supports video and audio.
"Does this mean that we can connect the Intensity card to the regular
DVI-D output of the graphics card of a second machine, which would be
sending out in a 1920 x 1080 resolution ? Have you tested this option
in your labs ?"
We thought of that but so far have been unable to find a graphics card which
outputs at standard TV resolutions such as 1920 x 1080, 1280 x 720, 720 x
486 and 720 x 576. If we could find one, then I would expect we could
capture it with Intensity using a DVI to HDMI adapter on the graphics card
output.
If you aware of such a graphics card, please let us know the brand and model
as we'd love to get one and test it. I realize you can directly connect a
big screen TV to the DVI output of computers but if you check the resolution
being used, it will not be a TV resolution.
Just let us know, thanks!
Dan May
Blackmagic Design
Quote:
Hi,
Australia says that the board won't act in all instances as a monitor device. In other words, it won't be able to give back EDID the same way a screen does.
It is not completely clear yet what this will mean in all real life situations, and probably in most cases it will act as expected. However, we know for sure when we can start and test with the production version of the board and the first public driver version.
We expect the first units to come in half of october. Please remind us and we can do a test.
Theo
BMD Europe
