Hello all,

Anyone done this?

I currently have a VP30 and an Oppo 970 just using HDMI and I am contemplating upgrading to a VP50 Pro and HD-SDI. (I also have a Samsung 5000 for HD).

However, one of my gripes about the VP30 is it's very poor support for attaching to a computer, at least for what I have tried. I have not found a way to get 480i to come out of the computer like I can with the 970, and it is downhill from there. Part of this I think is the skimpy EDID profile in th VP30, I have asked DVDO about this but they don't seem too interested.
There is of course a long list of gripes about video cards in general, as well as a variety of issues with HTPC as well. It is very hard to match the simplicity and quality of the solution I have now.

So, my idea is, what about piping HD-SDI directly from a computer to a scaler? HD-SDI cards for computers are readily available, the question is, could this be made to work?

I am not looking to play BluRay from the computer mind you, I more interested in being able to play all the other content that I have on my computer such as perhaps DVR content. If this could work, the computer makes for a very powerful and versatile mpeg(etc.) decoder.

Any thoughts? I think this would be a really cool thing.

If someone has already done this, please point me in the right direction.

Thanks

-Jeff333

How would you be getting 480i out of your computer? Native Mac/PC video format is progressive, with either VGA or DVI output interfaces. Any top-notch scaler should be able to accept either of these formats. To get HD-SDI out from your computer would entail adding an AJA or BlackMagic PCI card and would not give any better results than you could acheive with DVI-D output.

How would you be getting 480i out of your computer? Native Mac/PC video format is progressive, with either VGA or DVI output interfaces. Any top-notch scaler should be able to accept either of these formats.

Computers can output just about any format you want, provided the display (or receiving device) can do it. If you feed progressive video to a scaler then the scaler is not doing the de-interlacing which is not what you want unless your computer has a really good de-interlacer.

To get HD-SDI out from your computer would entail adding an AJA or BlackMagic PCI card and would not give any better results than you could acheive with DVI-D output.

Yes, you would need a potentially expensive card.

What are you basing this on? Why do you suppose anyone bothers with SDI or HD-SDI at all if it is not any better than HDMI/DVI? And since to our mutual knowledge we don't know of anyone who has done this, how do you know it would not give you better results? Please present evidence, personal experience, or at least a reasonably informed reason why you think so rather than making these assumptions. At least you could say "I personally don't think it would be any better because of X" or something.

I encourage you to read about the differences in the digital chain in SDI vs. HDMI/DVI first before you comment on this type of thing.


-Jeff333

There are at least two cards capable of outputing SDI, the Quadro FX 5600 SDI and Quadro FX 4600 SDI from NVidia. When you find out their price I'm quite sure you'll prefer to stick with DVI or HDMI unless you have really deep pockets.

Javier

SDI and HD-SDI do not give superior picture quality, since they are only transport mechanisms for transmitting digital image data. SDI modded DVD players are being touted as giving better image quality because the SDI interfaces are bypassing the PanelLink IC (HDMI interface), which is claimed to be causing image degradation. SDI and HD-SDI are widely used in professional video systems because of the prevalence of it as an interface standard, not because it gives "better" image quality.

I've never seen a computer that outputs interlaced video as an option. Maybe there are some "AV" type of computers that utilize PCI video cards which have interlaced output as an option, but mainstream computers do not. They have many options for color bit depth and pixel resolution, but the image is always output as progressive, whether it be analog VGA or digital DVI.

If you were to install a PCI-SDI interface card, all it would be doing is serializing the exact same image data that is being output on the DVI interface (assuming that you have one). So it would be a total waste of money, unless you needed to interface to equipment that would only accept an SDI signal. It your time and money .....

SDI and HD-SDI do not give superior picture quality, since they are only transport mechanisms for transmitting digital image data.

LOL! :D

I love how you state this as fact when it has been disproved by so many people that it isn't even funny :o

I think you need to actually look at both on a high-end system before making blanket claims like this :rolleyes:

-Gary

There are at least two cards capable of outputing SDI, the Quadro FX 5600 SDI and Quadro FX 4600 SDI from NVidia. When you find out their price I'm quite sure you'll prefer to stick with DVI or HDMI unless you have really deep pockets.

Javier

Well, I am building a $75k dedicated home theater, it is all in perspective. It might be a good investment---but only if it works or has some benefit. Maybe, maybe not. That being said I totally forgot that Nvidia made cards with SDI ;-)

-Jeff333

There are at least two cards capable of outputing SDI, the Quadro FX 5600 SDI and Quadro FX 4600 SDI from NVidia. When you find out their price I'm quite sure you'll prefer to stick with DVI or HDMI unless you have really deep pockets.

Javier

BTW, there are other cards that output SDI. Google Black Magic.

-Jeff333

SDI and HD-SDI do not give superior picture quality, since they are only transport mechanisms for transmitting digital image data. SDI modded DVD players are being touted as giving better image quality because the SDI interfaces are bypassing the PanelLink IC (HDMI interface), which is claimed to be causing image degradation. SDI and HD-SDI are widely used in professional video systems because of the prevalence of it as an interface standard, not because it gives "better" image quality.

Well, I guess the point here is, are the things being "touted" actually better. Don't dismiss it until you see for yourself. No-one is arguing here about the merits of one digital transport vs. another. As you say yourself, it is where you start getting your data.


I've never seen a computer that outputs interlaced video as an option. Maybe there are some "AV" type of computers that utilize PCI video cards which have interlaced output as an option, but mainstream computers do not. They have many options for color bit depth and pixel resolution, but the image is always output as progressive, whether it be analog VGA or digital DVI.

You have never seen a computer with "TV-OUT"? They have been around for a very long time. I have a laptop with a composite video out. My main computer has composite, S-video, component, etc. In the options for the nvidia software there is a button and option specifically for outputting 480I---but it can do other interlaced options as well. The limitation is that it won't let you activate it if it does not detect a compatible display.

That being said, this is only relivant if you want to play a DVD from the computer and output it to an external scaler. I don't need to do that since I already have a good solution for it. And, all the material I have that I want to watch from the computer is already progressive anyways.

If you were to install a PCI-SDI interface card, all it would be doing is serializing the exact same image data that is being output on the DVI interface (assuming that you have one). So it would be a total waste of money, unless you needed to interface to equipment that would only accept an SDI signal. It your time and money .....

Are you speaking from personal experience with said equipment? Please give examples.

-Jeff333

LOL! :D

I love how you state this as fact when it has been disproved by so many people that it isn't even funny :o

I think you need to actually look at both on a high-end system before making blanket claims like this :rolleyes:

-Gary

Well, I don't want to turn this thread into which digital transport is better as I am sure that has been beat to death elsewhere on this forum already.

I think what we can agree on is that it CAN possibly make a difference where that data is being sourced from. Garbage in, garbage out.

So, in theory if this could be done from a computer in the way I am thinking, it might have some advantages. I find it especially interesting that I can't find anyone who has done it. That either means that there is not point and it is not worth doing or just that no one has bothered to try it.

I am not expecting superior results from SDI vs. HDMI. I am more interested in the versatility of being able to display more types of content, use more different codecs, and all the while bypassing all the tweaking and potential problems that revolve around conventional PC video cards and interfaces. The easy of use, interface, and automatic features of hardware scalers is a big advantage in my experience. They are almost plug and play.

But there could be problems too. I like to watch alot of Anime and use software to view the subtitles. Would the SDI interface bypass this? Maybe. Until I try it myself or get in touch with someone who has, I have no idea what the results are. If only to be content one way or the other I think it is worth tracking down the answer.

-Jeff333

Jeff. You can believe whatever you want to believe. Unfortunately, what you want to believe and what some others are trying to promote are not technically correct. Nobody has PROVEN anything in this forum regarding the superiority of SDI over DVI/HDMI. All they have managed to do is to bypass the HDMI interface circuitry with their SDI modifications. The improvement was caused by the bypass, not the SDI.

Here's a listing of SDI related threads. Why don't you go through all of this stuff and see what actually did transpire (I have).

SDI Modded Players t=908628,955108,885946
SDI Modded Oppo t=857581&page=4
New SDI King t=828704
HD-SDI t=885329,972968,1008457
HD-SDI Modification t=1030572&page=2
Official HD-SDI Thread t=1042709&page=2

If you want to waste your time and money screwing around with SDI interfaces with the misguided notion that it is somehow going to work some sort of image magic, go right ahead. I was trying to give you some straight info on the subject, but apparently you aren't interested. You said that you were primarily interested in improving the interface between your computer (progressive) video output and your processor. You probably need a better processor if you are not getting the results expected - you don't need SDI. The best processor/scaler around for doing this sort of thing is the Barco ImagePro HD. They are expensive!!

ps - I might add that I own a number of pieces of video gear (noise reduction processor, TBC, scaler, etc) all of which have SDI/HD-SDI interfaces. I use a reference grade monitor that also has an HD-SDI interface. So I certainly do not have any bias per se against SDI.

Jeff - you can go out and purchase a Radeon 3870 graphics card, a DVI/HDMI splitter and a DVI/HDMI switch for substantially less than what it would cost you to upgrade from a VP30 to a VP50pro or any other comparable processor. The splitter-switch combo will allow you to conveniently feed your monitor/projector directly from the computer DVI/HDMI graphics output. The switch would (of course) go on the output of your VP30.

The one thing you DON'T want to do is to take your computer graphics output and SCALE it with your VP30, because that amounts to double scaling and will always give inferior image quality in comparison to a direct unscaled feed (of the appropriate resolution). Note that although Nvidia gets most of the attention in the mainstream press for graphics superiority, the Radeon 3870 actually will deliver better video image quality. Over the past year, there have been a couple of magazine comparison shootouts between the two vendor's products, and the new Radeon quite clearly had the better antialiasing, de-interlacing and absence of scaler ringing. Unfortunately, I tossed the magazine articles awhile back, so I can't directly refer to them. I would venture to say that with this latest generation Radeon, its image processing is probably as good or better than what your VP30 will do, and you can easily set the pixel output resolution to exactly match the native resolution of your monitor/projector. This basic setup is what I'm planning on doing in my system, when I get the new computer.

One significant drawback of the PC imbedded SDI interface is HDCP incompatibility. If you ever decide that you want to play back commercial DVD or BD in the computer, you are screwed with the SDI interface because of its lack of support for copy protection. With an HDMI based output interface, at least you are future-proofed.

Originally Posted by fastl
SDI and HD-SDI do not give superior picture quality, since they are only transport mechanisms for transmitting digital image data.

LOL! :D

I love how you state this as fact when it has been disproved by so many people that it isn't even funny :o

I think you need to actually look at both on a high-end system before making blanket claims like this :rolleyes:

-Gary

No, Fast! quite correct in the context he';s speaking. Non corrupted data flowing over HDMI is no better than data flowing over SDI. A byte is a byte. Now if the data stream is altered in it's initial values by the HDMI interface, then yes it can look worse. But then it's no longer the exact same data either.

SDI/HDSDI is far more robust than HDMI as it's an singal unbalanced serial stream versus HDMI's four balanced high speed pairs. HDSDI 1.5gbs can go over 1000 feet on RG6 cable. Try that with copper HDMI.

Glimmie

1000 feet of 1694A would exhibit 73 dB of insertion loss at 1.5 GHz, which is more than an adaptive SDI receive (terminating) equalizer can cope with. So, most likely you would have to install an intermediate repeater to get the link to work reliably. You can also make a DVI-D/HDMI link work over 1000 feet of good quality cable using a repeater adaptive-equalizer configuaration analagous to the SDI setup.

Beside the point of my discussion anyway. Both SDI and DVI are nothing more than digital data transport mechanisms. As long as the data gets to the end error free, they both give essentially identical results. The PanelLink bypass operation will give the same picture improvement with either SDI or DVI interfaces, providing they are installed properly. It's a lot easier buzzing a single 3/8 diameter hole in someone's back panel for a BNC than trying to punch a cutout for another D-connector, so maybe that's the major attraction of the SDI mod.

Jeff is probably experiencing what others have found happen when they feed computer graphics through their beloved VP - it doesn't look as sharp as what you get directly off the computer monitor. That is what happens when you go through multiple stages of scaling. With VGA, an additional problem is the oversampling A/D converter process in the VP. That's why I suggested he forget the VP altogether and feed his video rig directly from a SOTA graphics card via DVI/HDMI. He also needs to compensate for the computer to video monitor gamma difference too, but that's another discussion.

Glimmie
As long as the data gets to the end error free, they both give essentially identical results.

that is the whole point of HD-SDI mods on blu-ray players for example, the "data" that comes from the HDMI port is not the same that you get from HD-SDI, this has been argued so many times it is pitiful

no one is saying HDMI sucks for video nor that it is any different than HD-SDI for transmission, the whole point of HD-SDI is that it bypasses needless junk, fluff, conversions and other PQ harming issues and gives a direct decoder output vs the HDMI output, HDCP and better cable performance is just a bonus, it is as simple as that, not very hard to understand

-Gary

Jeff. You can believe whatever you want to believe. Unfortunately, what you want to believe and what some others are trying to promote are not technically correct. Nobody has PROVEN anything in this forum regarding the superiority of SDI over DVI/HDMI. All they have managed to do is to bypass the HDMI interface circuitry with their SDI modifications. The improvement was caused by the bypass, not the SDI.

Here's a listing of SDI related threads. Why don't you go through all of this stuff and see what actually did transpire (I have).

SDI Modded Players t=908628,955108,885946
SDI Modded Oppo t=857581&page=4
New SDI King t=828704
HD-SDI t=885329,972968,1008457
HD-SDI Modification t=1030572&page=2
Official HD-SDI Thread t=1042709&page=2

If you want to waste your time and money screwing around with SDI interfaces with the misguided notion that it is somehow going to work some sort of image magic, go right ahead. I was trying to give you some straight info on the subject, but apparently you aren't interested. You said that you were primarily interested in improving the interface between your computer (progressive) video output and your processor. You probably need a better processor if you are not getting the results expected - you don't need SDI. The best processor/scaler around for doing this sort of thing is the Barco ImagePro HD. They are expensive!!

ps - I might add that I own a number of pieces of video gear (noise reduction processor, TBC, scaler, etc) all of which have SDI/HD-SDI interfaces. I use a reference grade monitor that also has an HD-SDI interface. So I certainly do not have any bias per se against SDI.

Please try to keep the conversation civil here.

OK, so after all the information on SDI here and from your personal experience, you would say that there is no obvious advantage to my idea.

Do you think their is any merit as to where SDI gets it data, vs. where HDMI gets its data?

The things I would wonder on SDI from a computer are:

* Would you get a normal video output from it like you do with a video card, or would you need to have a video card WITH SDI for that? What do you actually get from an SDI-only card if you had one?

One of the things I love about my VP30 is the user interface. This unit is very easy to setup and use. Computers, on the other hand, I think leave alot to be desired when it comes to using them for scaling and deinterlacing. This is why I am thinking, if I only use the computer for outputting a datasteam, and all the "picure controls" are in the hardware scaler, I possibly side-step the interface problem.

-Jeff333

Jeff - you can go out and purchase a Radeon 3870 graphics card, a DVI/HDMI splitter and a DVI/HDMI switch for substantially less than what it would cost you to upgrade from a VP30 to a VP50pro or any other comparable processor. The splitter-switch combo will allow you to conveniently feed your monitor/projector directly from the computer DVI/HDMI graphics output. The switch would (of course) go on the output of your VP30. .

Yes, I have heard good things about the Radeon cards. There is of course an arms race in this area and each new product from nVidia and ATI ups the anti once more.

The one thing you DON'T want to do is to take your computer graphics output and SCALE it with your VP30, because that amounts to double scaling and will always give inferior image quality in comparison to a direct unscaled feed (of the appropriate resolution). Note that although Nvidia gets most of the attention in the mainstream press for graphics superiority, the Radeon 3870 actually will deliver better video image quality. Over the past year, there have been a couple of magazine comparison shootouts between the two vendor's products, and the new Radeon quite clearly had the better antialiasing, de-interlacing and absence of scaler ringing. Unfortunately, I tossed the magazine articles awhile back, so I can't directly refer to them. I would venture to say that with this latest generation Radeon, its image processing is probably as good or better than what your VP30 will do, and you can easily set the pixel output resolution to exactly match the native resolution of your monitor/projector. This basic setup is what I'm planning on doing in my system, when I get the new computer. .

Yes, I understand not to double-scale. If I were to connect the computer to the VP30, I would turn off any scaling on the computer.

Anandtech has had a good series of reviews on this. I forget who one the last one. I know ATI historically won them, but the very last one they were neck and neck. However, I am not worried about de-interlacing standard DVD. I want to play downloaded or similar media that is generally already progressive. I "might" play Blu-Ray on it, I dunno.

One significant drawback of the PC imbedded SDI interface is HDCP incompatibility. If you ever decide that you want to play back commercial DVD or BD in the computer, you are screwed with the SDI interface because of its lack of support for copy protection. With an HDMI based output interface, at least you are future-proofed.

I am surprised you say this. First, I have seen that SDI sometimes bypasses HDCP on modded DVD/Blu-Ray players, so it stands to reason it *might* do the same on a PC, just theory though.

Second, doesn't software like SlySoft AnyDVD render this issue completely irrelivant?

-Jeff333

Jeff is probably experiencing what others have found happen when they feed computer graphics through their beloved VP - it doesn't look as sharp as what you get directly off the computer monitor. That is what happens when you go through multiple stages of scaling. With VGA, an additional problem is the oversampling A/D converter process in the VP. That's why I suggested he forget the VP altogether and feed his video rig directly from a SOTA graphics card via DVI/HDMI. He also needs to compensate for the computer to video monitor gamma difference too, but that's another discussion.

Actually, I think the real problem is that the EDID profile in products like the VP30 and similar only support VGA (640x480), SVGA (800x600), XGA (1024x768), SXGA (1280x1024) resolutions. So unless you are a PowerStrip guru and can get other settings to work, you are stuck with these resolution options making it pretty impossible to get what you need. If their EDID profile supported the full range of video formats, I would set my computer display to the native pixel resolution of my source material and turn off any scaling in the computer. Then the VP30 could scale it, and be the only thing scaling it.

On the gamma front, or any settings like it for that matter, I have not seen a computer that could save it's video settings in an intuitive manner using an interface like what the VP30 has. So what happens is you end up constantly fiddling with the settings in the computer to try and get good results depending on the media you are showing. What's worse, good luck with calibration because in most cases you can't display test patterns AND adjust video settings (easily) at the same time like you can with a hardware scaler... this makes the adjustments themselves painstaking.

Thus, my theory is, if I output just raw data from the computer to the scaler, I would bypass the cumbersome computer interface.

What do you think?

-Jeff333

Jeff,

I suspect you will find this thread useful:
http://www.avforums.com/forums/showthread.php?t=746525&highlight=sdi

Jeff,

I suspect you will find this thread useful:
http://www.avforums.com/forums/showthread.php?t=746525&highlight=sdi

Wow, this is exactly the information I am looking for, someone who has actually done it! Thanks man!

-Jeff333

Glimmie

1000 feet of 1694A would exhibit 73 dB of insertion loss at 1.5 GHz, which is more than an adaptive SDI receive (terminating) equalizer can cope with. .


My bad - 100 feet! Over 200 feet I use 7731 and have some 400 foot runs at work with that.

that is the whole point of HD-SDI mods on blu-ray players for example, the "data" that comes from the HDMI port is not the same that you get from HD-SDI, this has been argued so many times it is pitiful

no one is saying HDMI sucks for video nor that it is any different than HD-SDI for transmission, the whole point of HD-SDI is that it bypasses needless junk, fluff, conversions and other PQ harming issues and gives a direct decoder output vs the HDMI output, HDCP and better cable performance is just a bonus, it is as simple as that, not very hard to understand

-Gary

But keep in mind that just because a device has an HDMI port does not automatically mean is has additional processing. HDMI can carry the same data as HDSDI. Now I do agree most DVD plaers have some processing built in. The temptation to add features by marketing departments is just too easy with digital processing.

But keep in mind that just because a device has an HDMI port does not automatically mean is has additional processing. HDMI can carry the same data as HDSDI. Now I do agree most DVD plaers have some processing built in. The temptation to add features by marketing departments is just too easy with digital processing.

of course Glimmie, but you and I both know how these manufacturers are, HD-SDI guarantees no fuss perfect decoder output, why mess with anything else? :p

up until recently BD players almost always output 4:4:4 YPbPr via HDMI, more conversions, was glad to see Panasonic do 4:2:2 on the BD30/50, makes for a better comparison to the HD-SDI output

-Gary

For SD SDI from a HTPC, the Sigma XCard with the Pixel Magic SDI add-on was a beautiful thing in its day. Pristine 480i output from a HTPC. I used it originally with a Holo3dgraph processor card. Unfortunately it emitted SDI with a negative polarity which posed some challenges for use with standalone processors. This was not a problem for use with a Crystalio which allowed you to toggle SDI polarity back and forth, but sadly DVDO has never enabled this feature in any of their products (despite pleading).

I went through a month long journey trying to get 480i DVI output from a HTPC to my VP50, including trying Linux as a potential solution. Had to throw in the towel in the end. There are a few threads on this subject you can find if you search, including one from someone who said he had it working.