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Posted By: AndrewSW 1080i or 720p? - 07/27/06 07:03 PM
How should I connect my DVD player to the TV? My DVD player is a samsung HD-931. It is supposed to upconvert to 1080i I believe, through a DVI port. I bought a DVI to HDMI to connect it to my Samsung DLP, but it doesn't look as good regular component inputs that is progressive (720p I believe). Is there settings that need to be changed on the dvd player? Anyone else have this player or one similar that has it hooked a certain way?

Thanks.
Andrew
Posted By: n8wrl Re: 1080i or 720p? - 07/27/06 07:35 PM
Doesn't it depend on the TV/Monitor? It will have a 'native resolution' that you should stick to. Otherwise, your DVD is upconverting to 1080i and your TV is whatever-converting to what it wants.

I tried one of those Oppo upconverting units and when it was set to 720p or 1080i it didn't look nearly as good on my Vizio 50" plasma. A little research revealed that the Vizio used a similar chipset/algorithm for its conversion so I must have been doing double-duty. It didn't look as nice.

I'd suspect 720p depending on the size of your TV.

-Brian n8wrl
Posted By: DrunkenWolf Re: 1080i or 720p? - 07/27/06 07:39 PM
Personally I'd avoid upconverting. You can't completely fill a 10 gallon bucket with 5 gallons of water no matter how fast your pour the water in.

The DVD Player should be set to progressive scan, which should output at 480p. If you must use upconversion I'd choose 720p in this case simply because it is progressive and is closer to the native resolution of the DVD. I have a samsung 1080p TV and I have my DVD player connected through component cables-I think it looks really good, but I'm free of OCD.
Posted By: alan Re: 1080i or 720p? - 07/27/06 07:42 PM
Hi Andrew,

If your Samsung DLP set has a native resolution of 720p (most do, unless it's the new Samsung with 1080p), then you should set the DVD player's HDMI output to the same as the set's native resolution. If your DLP set is 1080p, then you could try setting the DVD player to upconvert to 1080i. Your DLP set will then de-interlace the 1080i to its native resolution of 1080p. It may look better than component video connections or it may not.

What sometimes happens is that component-video connections may produce better image quality than an HDMI connection, because the HDMI link uses lots of bits for the anti-copy protection digital "handshake" (and bits devoted to anti-copy protection are bits not used for image quality). Component video connections do not have to deal with complex anti-copy digital handshakes, and hence may look superior to HDMI.
Posted By: DrunkenWolf Re: 1080i or 720p? - 07/27/06 07:48 PM
Alan,
I'm not familiar with the specs for HDMI, but I would suspect that HDMI has higher bandwidth compared to component or at least sufficient bandwidth to move both the copy protection bits and the actual data. Or has Hollywood really gone insane?
Posted By: alan Re: 1080i or 720p? - 07/27/06 10:13 PM
Drunken Wolf,

It's not just a matter of bandwidth, but rather the number and complexity of processing steps. Component video, which is analog, is only limited by the bandwidth of the amplifier used to drive the cable and the receiving OP-Amps to convert it to whatever is necessary - 720p or 1080i.

Most OP-Amps today can easily handle over 100 MHz of bandwidth. But HD signals, either 720p or 1080i, require only 35 MHz of bandwidth; 1080p requires 65MHz of bandwidth, so all of these are easily accommodated by component video connections. The real issue is what happens to the data once it's received. In the case of component video (it's an analog signal), it is processed by the ADCs (analog to digital converters) and sent directly to the display device.

But in the case of HDMI connection, the data must be sent to another chip set (no ADCs needed because it's a digital connection), which then has to strip out the video information, then decide what to do with it. A different chip set deals with the anti-piracy handshake process. This processing can have bit jitter, clocking issues, missed or corrupted bits, etc. It's still a contentious subject in "Pure Digital" video systems.

All of this is bypassed with component video connection, where the audio is routed with separate cables.

Using HDMI, there are up to five different digital chip sets involved in separating the video, the piracy codes, and the digital audio stream.

There are issues in digital audio as well when the clock changes or bit stream changes from one Dolby Digital system to another or from PCM to Dolby Digital. And the processing of the audio stream is relatively simple compared to the video stream.

So the bottom line is that there are just too many digital processing steps with HDMI connection.
Posted By: SirQuack Re: 1080i or 720p? - 07/27/06 11:27 PM
Before I built my HTPC, I used my Panasonic S97S Upconverting DVD player with my Sanyo Z2 (1280 x 720 native). I also used a DVI/HDMI cable. On the projector I had to make sure I had the correct input selected. To me I thought the 720p selection was better than 1080i, since it matched the native resolution of the projector. Compared to 480i or 480p, it was much better.
Posted By: JohnK Re: 1080i or 720p? - 07/28/06 03:12 AM
Andrew, your new TV is 1080p. Your player can deinterlace the i(of a standard 480i DVD)to p and you say that it can scale the 480 to 1080. Your TV can also do both of these processes, and if the player hasn't previously done it, the TV has to do it in order to display a complete picture on the 1080p display. The question would be whether the player or the TV does a visibly better job of deinterlacing and scaling. Try all possible combinations, e.g. the player outputing 480i, 480p or 1080i(if it in fact outputs 1080i)and see if one looks better.
Posted By: AndrewSW Re: 1080i or 720p? - 07/28/06 06:59 AM
Thank you for all of the responses. Too late tonight, but i'll try the cominations sometime this weekend. I'm sure i'll run into more questions, and i'll let y'all know which I think looks best.

Andrew
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