Hacking Fixing vWii Mode

[nastys]

Welp, there's a problem...
Those files are part of the Wii U OS and modifying them will break the signature and cause a brick, and vWii cannot be launched from redNAND. Although there's a chance that modifying only the vWii-specific files won't cause a brick, it's still too risky.
However, it looks like /storage_slc/title/00050010/10004000/code/deint.txt (00050010-10004000 being cafe2wii; "\r\n" line endings) contains some parameters for the "deinterlacer", but I have no idea what it actually does (I only know it's used by nn_cmpt.rpl) nor if it's safe to edit.

I'd need the help of an experience developer who knows a way to redirect and reload (or patch in memory) the Wii U OS files after entering "CFW", while still being able to launch vWii.

EDIT: I'd patch the function 0x2002A88 in nn_cmpt.rpl, before it loads the DMCU firmware.
EDIT2: I think I'll try patching it with WUPS.

A while ago, I read on this forum that both GBA on 3DS and Wii on Wii U had ~10 ms of input lag, but I can't seem to find the post.

That's nothing.

 

[nastys]

Edit: It's also worth mentioning that the Wii U screws up the Wii's aspect ratio, according this video:

It looks the same on both consoles to me (16:9 setting, 4:3 display). Also, he set his Wii U to 480p, which is a huge mistake since vWii looks much sharper at 1080p.
The actual resolution of Wii software is less than 480p due to underscan, and vWii "zooms in" to compensate and get a full-screen 480p+ picture.

 

[kingjinxy2]

It looks the same on both consoles to me (16:9 setting, 4:3 display). Also, he set his Wii U to 480p, which is a huge mistake since vWii looks much sharper at 1080p.
The actual resolution of Wii software is less than 480p due to underscan, and vWii "zooms in" to compensate and get a full-screen 480p+ picture (and 480p output is not enough pixels to get a sharp overscanned picture).

As Bob said in the video, he did set his Wii U to 480p in order to compare the Wii U's HDMI output with the modded Wii's HDMI output. To be frank, I don't know why, but it looks like he set his consoles to 16:9 and then squished them to display them side-by-side.

To truly prove that the Wii U does not mess up the Wii aspect ratio, use the 240p Test Suite's linearity test. Be sure to enable 480p modes in the options menu, because I don't know if the Wii U will correctly scale 240p or 480i. (Note that the TV must be set to display 4:3) With a ruler, measure the diameter of the circles. If the diameter is the same in all directions, then the aspect ratio is correct.

 

[nastys]

As Bob said in the video, he did set his Wii U to 480p in order to compare the Wii U's HDMI output with the modded Wii's HDMI output. To be frank, I don't know why, but it looks like he set his consoles to 16:9 and then squished them to display them side-by-side.

480p output is not enough pixels to get a sharp overscanned picture - it needs to be higher than the cropped/native resolution times 2, which is >912p (Nyquist–Shannon sampling theorem).

 

[kingjinxy2]

480p output is not enough pixels to get a sharp overscanned picture - it needs to be higher than the cropped/native resolution times 2, which is >912p (Nyquist–Shannon sampling theorem).

Could you please explain to me why this is necessary?

Why couldn't the Wii U just do exactly what the GCVideo project does for GameCube and Wii? That basically does digitally what the AV out on the Wii/GC does---it outputs the full 720x480 with an aspect ratio of 4:3.

I understand that 1080p output is sharper, but it has its own issues, as @Extrems pointed out.

 

[nastys]

Could you please explain to me why this is necessary?

Why couldn't the Wii U just do exactly what the GCVideo project does for GameCube and Wii? That basically does digitally what the AV out on the Wii/GC does---it outputs the full 720x480 with an aspect ratio of 4:3.

Because the Wii was designed for CRTs and expects the TV to overscan, all Wii software actually has a black frame around the picture. vWii simply zooms in to get rid of the black borders (by applying a scaling filter to every single pixel), but there are not enough samples/pixels to do it while preserving the sharpness and details of the original picture.
According to the theorem, 1080p should be more than enough samples/pixels to faithfully represent the original picture, and in fact, it does look a lot sharper and better than 480p (as well as 720p).
If we could somehow disable this overscan "filter", it would probably look as sharp as a modded Wii.
EDIT: Also, 1080p has far less overscan than 480p.

I understand that 1080p output is sharper, but it has its own issues, as @Extrems pointed out.

The cropped output (and maybe the colour bleeding) is caused by the overscan "filter", I'm pretty sure.


EDIT: Unfortunately, it seems that vWii ignores the Wii U underscan settings (for whatever reason, AVMSetTVUnderScan(0) is called).
I've tried stubbing some functions with WUPS and it works, but I haven't found whatever applies the scaling filter/overscan yet. However, I have managed to do something that affects the black frame, sort of...

 

[PlayNeth]

I'm extremely glad my thread actually grabbed a lot folk's attention. I have faith my friends, that soon we'll figure out how to disable that dumb filter and the Wii U will finally become the ultimate Nintendo console.

 

[kingjinxy2]

I'm extremely glad my thread actually grabbed a lot folk's attention. I have faith my friends, that soon we'll figure out how to disable that dumb filter and the Wii U will finally become the ultimate Nintendo console.

Personally, I think that you should rename the thread to something like "Fixing vWii Mode" to make it more general and eye-catching, but you don't have to if you don't want to.

'SLIGHTLY OFF-TOPIC'
I realize that it may be out of the scope of the thread, but I think that the Wii U needs to be able to boot much more quickly into vWii. I know that you can hold B on the GamePad, but it's still incredibly slow. I would like the ability to simply power on the GamePad, choose Wii U or vWii mode, and go.

For example, with BootMii and USB Loader GX, I can power on my Wii and be on the game selection screen in about 7 seconds, getting into gameplay in about 20-30, depending on the game. This takes much longer on Wii U, especially if you don't boot directly into vWii mode. Obviously, we don't have anything like BootMii for Wii U, but it would be nice to have a feature like it someday.
'END SLIGHTLY OFF-TOPIC'

 

[PlayNeth]

Personally, I think that you should rename the thread to something like "Fixing vWii Mode" to make it more general and eye-catching, but you don't have to if you don't want to.

'SLIGHTLY OFF-TOPIC'
I realize that it may be out of the scope of the thread, but I think that the Wii U needs to be able to boot much more quickly into vWii. I know that you can hold B on the GamePad, but it's still incredibly slow. I would like the ability to simply power on the GamePad, choose Wii U or vWii mode, and go.

For example, with BootMii and USB Loader GX, I can power on my Wii and be on the game selection screen in about 7 seconds, getting into gameplay in about 20-30, depending on the game. This takes much longer on Wii U, especially if you don't boot directly into vWii mode. Obviously, we don't have anything like BootMii for Wii U, but it would be nice to have a feature like it someday.
'END SLIGHTLY OFF-TOPIC'

Oh trust me, i very much want to rename this thread to something similar to that but iirc only moderators are able to do it

 

[PlayNeth]

Oh trust me, i very much want to rename this thread to something similar to that but iirc only moderators are able to do it

Done. Pm'd a moderator to help me with that lol

 

[Sonic Angel Knight]

This is a interesting thread. Thanks for sharing this. While I'm not as tech savy about somethings or as sensitive as others, I'm glad people are able to point out things like this. Honestly I have a bad eye sight that I need to wear glasses to see, so that could be why I'm not noticing such things unless I get too close for comfort on the tv.

Now and days, I just use my wii u game pad, mostly for playing emulators. The only thing that bothers me sometimes is the colors, and sharpness. I don't have reasons why, but retro games don't look as sharp on there and sometimes the colors don't match my tv. I just assume the gamepad is right ant try to adjust the tv settings to match it. But I gave up on it cause it wasn't worth the time. I just accepted the game pad as correct and my tv as "needs upgrad" But now I don't have to thanks to this thread.

 

[nastys]

There's a chance at least some of the issues are "caused" by the DMCU's firmware (remember that Wii SDK bug that makes everything blurry?).
Does anybody know where it's stored? I've only found a hex dump in the vWii launcher.

 

[kingjinxy2]

There's a chance at least some of the issues are "caused" by the DMCU's firmware (remember that Wii SDK bug that makes everything blurry?).
Does anybody know where it's stored? I've only found a hex dump in the vWii launcher.

From the fail0verflow site (https://fail0verflow.com/blog/2014/console-hacking-2013-omake/), there is this blurb about the DMCU:

DMCU
You may have noticed that good old VI (the display controller / Video Interface of ye olde GameCube and Wii) is gone. Huh? How does that work? Turns out they’re emulating that in software and translating its configuration to the R7xx’s CRTC registers. But where does this emulation software run? Sneaky: they added a special microcontroller to the Latte just for this purpose. The DMCU is a 68HC11 compatible 8-bit CPU whose sole purpose is to perform VI emulation. It has a frontend hardware shim that looks like VI to the Wii software, and behind the scenes it translates those registers to the Radeon’s, including upscaling configuration. cafe2wii loads the DMCU’s firmware (the DMCU doesn’t seem to be active in Wii U mode). It has its own dedicated RAM and access to both the faux-VI back side and the Radeon’s register area. There is also a little mailbox to talk to it from vWii mode: the System Menu and IOS use this to configure the 4:3 stretch mode for Virtual Console games (which is why The Homebrew Channel accidentally ends up in the wrong mode: after a recent update, the System Menu thinks it’s a Virtual Console title due to its title ID starting with ‘L’ and sets up that special mode). Presumably it also got an update when gamepad support for vWii showed up, though I haven’t looked at the firmware again since then.

If the author's hypothesis is true, then the DMCU firmware must be contained within the 4.0.0 update:
https://en-americas-support.nintendo.com/app/answers/detail/a_id/1436/~/system-menu-update-history

• New Features
  • A feature to output video and sound to the Wii U GamePad when using Wii Mode.
  • A feature to automatically receive recommended software and demo titles from Nintendo using SpotPass.
  • Support for USB keyboards.
  • An option to disable use of a Nintendo Network ID on non-Nintendo hardware.
  • Support for Dolby® Pro Logic® II Surround Sound when playing Wii software.

I also find it interesting that Dolby Pro Logic II support wasn't already part of vWii mode, as it only ever requires stereo audio output and a decoder. Even with this update, whenever I played DPLII-compatible games on my Wii U over HDMI, I still had to manually set the receiver to decode the audio. Why Nintendo doesn't just decode it for you and output the result as PCM 5.1 is beyond me, as then you wouldn't need to switch DPLII off on the receiver for stereo sources like you need to on a real Wii.

@nastys You may want to contact marcan if you can't find the DMCU firmware, as he apparently wrote the article on fail0verflow. Unfortunately, I have no idea how to contact him.

 

[Deleted member 42501]

There are some things in this thread you may find interesting:

https://gbatemp.net/threads/vwii-in-480p-automatically.530221/

I'd like to see the vWii graphics fixed as well because there are noticeable artifacts due to how lazy Nintendo were with this. 480p at least gives a better raw signal to play with but still...

 

[nastys]

480p at least gives a better raw signal to play with but still...

Not at all. All pixels are interpolated for no reason (making everything blurry at <= ~912p), and it has the most overscan. 1080p looks much sharper, but the output still has 16 pixels of overscan (why, Nintendo???) and chroma shift.

 

[Deleted member 42501]

But thats like, totally your opinion dude.

 

[nastys]

But thats like, totally your opinion dude.

No, it's simple maths, because:

• 480p has way more overscan than 1080p (vWii just cuts off 16 pixels per side from the output)
• every single pixel is filtered, but there are not enough pixels to sample the picture faithfully (Nyquist-Shannon sampling theorem)

If you think 480p looks better, then good for you, but technically, the 1080p mode is more faithful to the original/raw picture.

 

[Deleted member 42501]

Its still like, totally your opinion dude.

There are way too many variables at play here to even have a semblance of objectivity in this discussion plus none of this makes the vWii picture quality any better so take what I gave you and use it if you can and if you can't then sit there quietly and be grateful I graced your thread with my presence.

 

[nastys]

There are way too many variables at play here

Like what?

(remember, we're taking about the raw output from the Wii U, not how well your TV processes it)

 

[kingjinxy2]

After doing some sleuthing, I have come to the realization that although it is really easy to get Wii U games, getting Wii U system updates is...impossible? I can't find anything online about them. Does anyone know how to get them from Nintendo's servers?