Cloning the Gamecube component cable

[Link83]

Thanks for the info Extrems! I've actually been trying to find a solid answer about this for awhile now: When the GCVideo is connected, does it take video before the encoder and keep it in 4:4:4, or does it pull from the video encoder in 4:2:2?

GCVideo is the video encoder.

So you're getting native 4:4:4 RGB with GCVideo? No 4:2:2 YCbCr is used with GCVideo?

I think theres some confusion arising here. Extrems is talking about the internal pixel format inside the GameCube GPU and how its originally RGB, but AFAIK there is no way for us to access those signals. GCVideo taps into the digital video signals between the GPU and the stock video encoder, which at that point have already been encoded into YCbCr 4:2:2.

I collected these snippets from the Nintendo SDK which might help explain:-

This is the sort of place for people who want to get the absolute very best audio/video possible from their console. Even if a mod only offers a 1% improvement in picture quality there are people who would want that.

See, that was sort of what I was trying to imply, but I did a poor job of it... The best image quality is going to be HDMI. I don't see a point in doing a gcvideo-lite in the cube because that's a middle solution in terms of output quality: it's only slightly better than the existing analog video, and not as good as the digital video, and 480p is less likely to be used on a CRT than 480i.

What I'm trying to say is, if you care about quality that much, use HDMI. If you want analog, just use the built-in component.

Its true HDMI gives you access to the pure digital video. However the GameCube and Wii do not output a perfect 720x480 resolution, in fact its actually 640x448 - this means that GCvideo has to add black bars all around the image so that it will meet the HDMI specification:-
https://www.gc-forever.com/forums/viewtopic.php?p=35025
The TV will still have to scale the image upto its native resolution (1080p/4k) and then the black bars typically cannot be defeated (Depending on your TV model it might offer a "Zoom" mode, but that usually cuts off some of the picture) This also means you cant display the game with the correct 4:3 aspect ratio.<Apparently this last sentence is incorrect, see Unseen's post below>

Using an analog signal allows the TV (Or scaler like the framemeister) to sample only the active lines/pixels, meaning we can get a full screen image with very minimal picture quality loss. In addition analog video outputs allow for easier connection to CRT TV's, for a more "authentic" retro experience.

HDMI mods for retro consoles are great and they certainly have their place, however these systems were simply designed with analog output in mind.

If that doesn't help explain why I would still like to see analog 31kHz RGB output from a Wii, then i'm not sure anything will convince you.

[DiegoPonga]

So @Link83, this breakthrough you propose for the Wii would be a 31KHz RGB signal in order to display 480p 4:4:4 through a SCART cable?

[citrus3000psi]

I don't see a point in doing a gcvideo-lite in the cube because that's a middle solution in terms of output quality: it's only slightly better than the existing analog video, and not as good as the digital video, and 480p is less likely to be used on a CRT than 480i.

I'm building the analog version only because I have pioneer v402 plasma. If I didn't have this tv I'd just stick with hdmi only.

[Link83]

So @Link83, this breakthrough you propose for the Wii would be a 31KHz RGB signal in order to display 480p 4:4:4 through a SCART cable?

Im not sure about the word "breakthrough"! I'm just hoping that someone might consider adapting the GCVideo Lite to also work with the Wii.

I would just like to see high quality analog video outputs available for the Wii - e.g. RGBs(SCART), RGBHV(VGA), YPbPr(Component) all of which could support both 15kHz(480i) and 31kHz(480p) modes. Even though 31kHz SCART and 15kHz VGA connections are typically considered "non-standard", they could still be connected to a scaler like the framemeister, which does support 31kHz RGBs on its mini DIN connector (Also please see my above edit reply to Guspaz for further reasons why I think analog output for the Wii would be a good idea)

[DiegoPonga]

So @Link83, this breakthrough you propose for the Wii would be a 31KHz RGB signal in order to display 480p 4:4:4 through a SCART cable?

Im not sure about the word "breakthrough"! I'm just hoping that someone might consider adapting the GCVideo Lite to also work with the Wii.

I would just like to see high quality analog video outputs available for the Wii, e.g. RGBs(SCART), RGBHV(VGA), YPbPr(Component) all of which could be compatible with both 15kHz(480i) and 31kHz(480p) modes. These could easily be connected to a scaler like the framemeister, which does support 31kHz RGBs (Also please see my above edit reply to Guspaz for further reasons why I think analog output for the Wii would be a good idea)

That would be very interesting. Wii, GameCube and Xbox hadn't support for 31KHz RGB. Those can only output EDTV/HDTV signals through component.

On the other hand, if OSSC is ever featuring HDMI input, probably I would change my mind and ask for a full GCVideo with HDMI output.

[Extrems]

However the GameCube and Wii do not output a perfect 720x480 resolution, in fact its actually 640x448 - this means that GCvideo has to add black bars all around the image so that it will meet the HDMI specification

This depends on the software. Standard GBI, for example, outputs real 720x486 or 720x576 using tiled rendering. 1440 samples width is also a thing now.

[Ikaruga11]

Wow this is exciting. I would love to see the Wii outputting pure digital through HDMI and a 480p 4:4:4 RGB mod, or at the very least an improved YPbPr output.

[Ikaruga11]

The best image quality is going to be HDMI. I don't see a point in doing a gcvideo-lite in the cube because that's a middle solution in terms of output quality: it's only slightly better than the existing analog video, and not as good as the digital video, and 480p is less likely to be used on a CRT than 480i.

What I'm trying to say is, if you care about quality that much, use HDMI. If you want analog, just use the built-in component.

So digital HDMI is better than analog Component, even on a CRT?

GCVideo-Lite is better than the official component cables?

[DiegoPonga]

The best image quality is going to be HDMI. I don't see a point in doing a gcvideo-lite in the cube because that's a middle solution in terms of output quality: it's only slightly better than the existing analog video, and not as good as the digital video, and 480p is less likely to be used on a CRT than 480i.

What I'm trying to say is, if you care about quality that much, use HDMI. If you want analog, just use the built-in component.

So digital HDMI is better than analog Component, even on a CRT?

GCVideo-Lite is better than the official component cables?

What he is telling you is that just a few CRTs are compatible with 480p or higher. 95% (probably more) of consumer CRTs are 480i.

That's why many people around here use an LCD along with an upscaler (such as the XRGB mini) or a scan converter (such as the OSSC.)

So, if you want the best quality for your GC, probably HDMI to an LCD is a good option. However, I'm skeptical with this statement. At least until someone develop a HDMI input for OSSC, which would be pretty interesting for those who have HDMI mods in their consoles.

[Unseen]

Its true HDMI gives you access to the pure digital video. However the GameCube and Wii do not output a perfect 720x480 resolution, in fact its actually 640x448 - this means that GCvideo has to add black bars all around the image so that it will meet the HDMI specification:-
https://www.gc-forever.com/forums/viewtopic.php?p=35025
The TV will still have to scale the image upto its native resolution (1080p/4k) and then the black bars typically cannot be defeated (Depending on your TV model it might offer a "Zoom" mode, but that usually cuts off some of the picture) This also means you cant display the game with the correct 4:3 aspect ratio.

Using an analog signal allows the TV (Or scaler like the framemeister) to sample only the active lines/pixels, meaning we can get a full screen image with very minimal picture quality loss. In addition analog video outputs allow for easier connection to CRT TV's, for a more "authentic" retro experience.

Please do not spread such misinformation. The aspect ratio of the signal generated by GCVideo-DVI is exactly the same as the aspect ratio of the analog composite output directly from the Gamecube - the blanking area around the active picture area on the composite output is seen as a black video signal by the TV. On CRT TVs, you usually do not notice the borders created by this, because you do not see the entire picture due to overscan.

This depends on the software. Standard GBI, for example, outputs real 720x486 or 720x576 using tiled rendering. 1440 samples width is also a thing now.

Let me guess, 1440 sample width are generated by using 240p/480i image parameters, but switching the pixel clock to 27MHz like in 480p mode? That breaks a few assumptions in GCVideo =(

[Link83]

Please do not spread such misinformation. The aspect ratio of the signal generated by GCVideo-DVI is exactly the same as the aspect ratio of the analog composite output directly from the Gamecube - the blanking area around the active picture area on the composite output is seen as a black video signal by the TV. On CRT TVs, you usually do not notice the borders created by this, because you do not see the entire picture due to overscan.

My apologies, it was not my intention to spread misinformation I have edited my above post.

I am slightly confused though - dont modern TV's disregard the blank overscan information over analog connections? At least on my TV I have overscan disabled, and using the GameCube/Wii I dont see any black bars at the top and bottom of the image, and with the correct aspect setting the TV seems to scales the image so it appears as 4:3.

[Extrems]

Let me guess, 1440 sample width are generated by using 240p/480i image parameters, but switching the pixel clock to 27MHz like in 480p mode? That breaks a few assumptions in GCVideo =(

That'd be 120 Hz. This is doubling horizontal timing values on top of that.

If you're curious: https://github.com/ExtremsCorner/libogc ... 8e9fd2f914
(I'm officially considering it for use as a column-interleaved stereo 3D mode)

[Einzelherz]

...now, before BobRocks has an aneurysm and starts accusing me of "being in on the scam", please remember that I have absolutely nothing to do with this project. My site and podcast are neutral ground for everyone other then eBay scammers and trolls. Don't shoot the messenger.

I wouldn't accuse you of that, and I don't genuinely think he's running a scam. I just think he's jerking his paying customers around with a lack of updates and being so many months behind on the project.

The fact that your podcast and his twitch stream are the only sources of info is just sad, and that's what the last 10+ pages of this thread say as well. I'm in no way the only person criticising him, so I'm not sure why you singled me out exactly...

This just in - enthusiasts for niche markets may also not be Fortune 500 CEO level businessmen.

[Xer Xian]

To whoever is concerned about video quality differences between the official component cable and GCVideoLite, I have both and, while I couldn't do a proper A/B comparison (I only have one OSSC), I didn't notice any personally. I don't have a capture card yet so I tried to take a few comparison shots of my PC monitor (Lacie electron IV) displaying both through an OSSC+Gefen vga to dvi converter (left GCVideoLite, right Component):

Broken Links

Occasionally you can spot pretty noticeable differences, but please assume a pretty big variance for these results (due to my crappy camera and lack of a tripod). All in all, I'd be equally happy to have one set or the other. I also wanted to test GBA games on both through the GBI software, but I can't find my freeloader to use it on my JPN (silver) Cube. Instead I did compare GCVideoLite (left) vs RGB (third party cable with composite video sync) (right) with the same setup as before, and this time I'd say there's a winner:

Broken Links

The GCVideoLite seems consistently better than RGB, at least with this 3rd party cable. I wasn't expecting a difference to be honest, and it kinda made me want to test the official RGB cable too.

(Fun fact 1: I had to use a third GC to test GBI over RGB - I couldn't get it to work through the RGB cable on the unit with GCVideoLite (which is PAL, and still has a functioning analog out). 480i was fine though, go figure.)

(Fun fact 2: I couldn't get GBI ULL to work with the GCVideoLite Cube. I didn't try with the official component cable, but it did work with the RGB cable on another GC)

Edit: I reuploaded the shots here: http://imgur.com/a/0ebk4 (if anyone's looking for non-resized pics, they can be downloaded from here) . I also figured I'd take a picture of the equipment as evidence.

[Extrems]

(Fun fact 1: I had to use a third GC to test GBI over RGB - I couldn't get it to work through the RGB cable on the unit with GCVideoLite (which is PAL, and still has a functioning analog out). 480i was fine though, go figure.)

If this is with the April 10th build, it'd be using the new oversampled mode by default, which isn't compatible with the on-board video encoder.

[Xer Xian]

Thanks Extrems, yes it's the latest build. So I guess it should work fine via OEM Component cable.

[bobrocks95]

...now, before BobRocks has an aneurysm and starts accusing me of "being in on the scam", please remember that I have absolutely nothing to do with this project. My site and podcast are neutral ground for everyone other then eBay scammers and trolls. Don't shoot the messenger.

I wouldn't accuse you of that, and I don't genuinely think he's running a scam. I just think he's jerking his paying customers around with a lack of updates and being so many months behind on the project.

The fact that your podcast and his twitch stream are the only sources of info is just sad, and that's what the last 10+ pages of this thread say as well. I'm in no way the only person criticising him, so I'm not sure why you singled me out exactly...

This just in - enthusiasts for niche markets may also not be Fortune 500 CEO level businessmen.

One tweet in 6 months isn't asking for a miracle. I guess if I'm REALLY the only one bothered by his lack of communication (spoiler: I'm not) I'll shut up about it.

[Ikaruga11]

What he is telling you is that just a few CRTs are compatible with 480p or higher. 95% (probably more) of consumer CRTs are 480i.

Yeah, the only CRTs that support anything above 15kHz (240p and 480i) are PC Monitors, HD CRTs, a few PVMs and BVMs. And those probably make up only about 5% of every CRT ever made.

That's why many people around here use an LCD along with an upscaler (such as the XRGB mini) or a scan converter (such as the OSSC.)

Well, yeah. A GameCube outputting HDMI to an LCD with a good upscaler looks fantastic. Doesn't GCVideo have its own internal upscaler? How does it compare to the XRGB mini and OSSC?

Aside from the supposedly higher image and sound quality, another reason to upgrade to GCVideo even if you have the official component cables is to future-proof your GameCube. Eventually, CRTs will die out. So when the time comes to use LCD, Plasma, OLED, etc., you'll have a much better signal that easily plugs into those displays and won't need to be converted from analog to digital by the display or an upscaler.

So, if you want the best quality for your GC, probably HDMI to an LCD is a good option. However, I'm skeptical with this statement. At least until someone develop a HDMI input for OSSC, which would be pretty interesting for those who have HDMI mods in their consoles.

I want to play my GameCube and Wii on a BVM CRT. I was just wondering if HDMI, official YPbPr, GCVideo-Lite YPbPr or GCVideo-Lite CSync RGB would give the best picture quality on a BVM. It sounds like HDMI from GCVideo is by far the best.

[Unseen]

That'd be 120 Hz. This is doubling horizontal timing values on top of that.

Nitpicker! ;)

If you're curious: https://github.com/ExtremsCorner/libogc ... 8e9fd2f914
(I'm officially considering it for use as a column-interleaved stereo 3D mode)

Thanks... Looks like I'll have to update GCVideo-DVI some day, because in theory it will completely mishandle these modes.

[lechu]

If you ordered from BadAssConsoles, he posted his upgrade form: https://www.badassconsoles.com/gcvideox-upgrade-form

Refund is an option.

[bobrocks95]

I also saw someone post this screenshot:

Spoiler

Is this back to implying that DIY kit purchases (at ~$65) are getting a free upgrade to the external version?
Or is he just no longer offering installation services, so your options are external or DIY?

[DarkAries]

So at this point what are the options for wanting to do a DIY install beyond buying the dev board preflashed from KNJN? I want to purchase one to try and do my own install and with so many pages I've lost track of what is available now.

[Link83]

To whoever is concerned about video quality differences between the official component cable and GCVideoLite, I have both and, while I couldn't do a proper A/B comparison (I only have one OSSC), I didn't notice any personally. I don't have a capture card yet so I tried to take a few comparison shots of my PC monitor (Lacie electron IV) displaying both through an OSSC+Gefen vga to dvi converter (left GCVideoLite, right Component):

Occasionally you can spot pretty noticeable differences, but please assume a pretty big variance for these results (due to my crappy camera and lack of a tripod). All in all, I'd be equally happy to have one set or the other. I also wanted to test GBA games on both through the GBI software, but I can't find my freeloader to use it on my JPN (silver) Cube. Instead I did compare GCVideoLite (left) vs RGB (third party cable with composite video sync) (right) with the same setup as before, and this time I'd say there's a winner:

The GCVideoLite seems consistently better than RGB, at least with this 3rd party cable. I wasn't expecting a difference to be honest, and it kinda made me want to test the official RGB cable too.

Edit: I reuploaded the shots here: http://imgur.com/a/0ebk4 (if anyone's looking for non-resized pics, they can be downloaded from here) . I also figured I'd take a picture of the equipment as evidence.

I'm curious to know if GCVideoLite also offers the "RGB Limited Range" option in the OSD settings like the HDMI version?
I only ask as looking at this picture in particular it looks like one image is perhaps brighter than the other?:-
http://i.imgur.com/Sl6WxCV.jpg
Although i'm aware you said to expect a big variance for the results.

Also can anybody tell me if GCvideo also supports a 640x480p output resolution, in addition to the default 720x480p I have seen in all the videos/screenshots?

[Xer Xian]

There's no OSD nor any configurable setting to be found on GCVideoLite, at least that I know of. Also, I'd like to stress that I actually compared two different configurations at that time: shots of Gamecube games show GCVideoLite against OEM Component cable while with the GBplayer I pitted GCVideoLite against a 3rd party RGBcvS cable (GCVideoLite is on the left-hand side in all cases). That was due to not finding my copy of the freeloader to boot the SDmedia launcher to load GBI on the JPN (silver) Cube. I've now found it but I think I'll defer any other comparison to when I'll be able to do a proper direct capture.

[Link83]

There's no OSD nor any configurable setting to be found on GCVideoLite, at least that I know of. Also, I'd like to stress that I actually compared two different configurations at that time: shots of Gamecube games show GCVideoLite against OEM Component cable while with the GBplayer I pitted GCVideoLite against a 3rd party RGBcvS cable (GCVideoLite is on the left-hand side in all cases). That was due to not finding my copy of the freeloader to boot the SDmedia launcher to load GBI on the JPN (silver) Cube. I've now found it but I think I'll defer any other comparison to when I'll be able to do a proper direct capture.

Ah ok, so the difference is probably just due to using a different input then.

[Ikaruga11]

There's no OSD nor any configurable setting to be found on GCVideoLite, at least that I know of.

So GCVideo (HDMI) > GCVideo Plug-in-Play (HDMI) > Official Component Cables > GCVideo Lite > VGA modded Component Cables > RGB Modded Component Cables > RGB (Sync on composite video) > S-Video > Composite > RF?

Also, I'd like to stress that I actually compared two different configurations at that time: shots of Gamecube games show GCVideoLite against OEM Component cable while with the GBplayer I pitted GCVideoLite against a 3rd party RGBcvS cable (GCVideoLite is on the left-hand side in all cases). That was due to not finding my copy of the freeloader to boot the SDmedia launcher to load GBI on the JPN (silver) Cube. I've now found it but I think I'll defer any other comparison to when I'll be able to do a proper direct capture.

Awesome! Can't wait for the GCVideo Lite Component vs. Official GameCube Component cables and the GCVideo Lite vs. 3rd party RGBcvS cable comparisons.

[Xer Xian]

Ah ok, so the difference is probably just due to using a different input then.

I don't know, actually GCVideoLite seems to produce a very slighly darker/less bright image in most of those shots, but I can't say if it's due to the video encoder or to measurement/human error. In any case, even if there's an actual difference it'll most likely be so minor to not be worth of concern (also if it's just brightness it can be adjusted on the display end).

@GeneraLight: Except for the last four elements of your ordering, I have absolutely no idea. Also please don't hold your breath for me, I really want a capture card to test out this and a lot of other stuff, but I'm trying not to buy one since I already know that then I'll spend even more time tinkering with different setups than actually playing the damn games

[Unseen]

I'm curious to know if GCVideoLite also offers the "RGB Limited Range" option in the OSD settings like the HDMI version?

The RGB output of GCVideo lite is always full range, because I assumed that people would want to connect it to a VGA input which also uses full range.

Also can anybody tell me if GCvideo also supports a 640x480p output resolution, in addition to the default 720x480p I have seen in all the videos/screenshots?

No, that would result in a cropped image for a number of poplar games.

[Link83]

I'm curious to know if GCVideoLite also offers the "RGB Limited Range" option in the OSD settings like the HDMI version?

The RGB output of GCVideo lite is always full range, because I assumed that people would want to connect it to a VGA input which also uses full range.

Ah I see, so since the SDK says:-
"Note that the range for Y is only 16<=Y<=235. This is in order to meet the requirements of the video encoder."
Does GCVideo Lite output limited range for YPbPr, and then convert/expand that to full range for RGB output? (SCART/VGA)

<EDIT>The GameCube's frame buffer color conversion in the SDK here:-
http://i.imgur.com/IOTjas1.png
Is labelled as an "RGB to YUV conversion"

However looking at the conversion formulas on this page:-
http://www.equasys.de/colorconversion.html
It doesnt appear to match their RGB to YUV conversion, but it does match the "RGB to YCbCr conversion"

I'm now a bit confused, should it be YUV or YCbCr?
Whats the correct formula needed to get RGB values from the digital YCbCr 4:2:2 data

Also can anybody tell me if GCvideo also supports a 640x480p output resolution, in addition to the default 720x480p I have seen in all the videos/screenshots?

No, that would result in a cropped image for a number of poplar games.

Thanks for the info. I had thought the GameCube's default resolution was 640x448, but if the horizontal resolution can vary between 640 and 720 pixels then it makes sense for GCVideo to only output 720x480.

[Unseen]

Does GCVideo Lite output limited range for YPbPr, and then convert/expand that to full range for RGB output? (SCART/VGA)

GCVideo Lite just outputs what it receives from the Gamecube in YPbPr mode, although with linear interpolation of the color channels to get 4:4:4 color from the 4:2:2 signal. If you consider that "limited range" then it is, although as far as I understand it there is no such thing as "full range YPbPr".

It doesnt appear to match their RGB to YUV conversion, but it does match the "RGB to YCbCr conversion"

I'm now a bit confused, should it be YUV or YCbCr?

It should be YCbCr (in the digital domain) or YPbPr (analog), but mis-labelling it as YUV is quite common.

Whats the correct formula needed to get RGB values from the digital YCbCr 4:2:2 data :?

It should be possible to derive the conversion matrices from Rec. 601, but I just took the values from Video Demystified.