WLED-MM-P4 USB JPEG Magic

[tulip willow]

A lot to explain, but basically:

1. My own WS281x driver, via Parallel IO on the P4. 16 Pins of hardware accelerated goodness and no extra hardware.

2. "Raw" pixel data access. You don't need to draw pixel by pixel any more. Bitmaps are cool.

3. USB Mass Storage is working. You can hot plug USB drives into a running system. You can even mount two. Storage limitations are now gone.

4. Pixel Processing Accelerator pipelines are fully working. Memory is now 2D-aware and RGB enabled.

5. JPEG decoder working. Bitmaps are smaller.

6. Combine 2,3,4,5 and we can steam image sequences off the USB disk live - and live rescale them as we like - to a certain extent. It only can downscale to 0.1 so below that maybe needs 2 steps but so far so good. 😁

This is 6 proof-of-concepts in a trenchcoat so it's far from optimized - but it's stable.

[tulip willow]

You can read more about what the Pixel Processing Accelerator can do here:

https://docs.espressif.com/projects/esp-idf/en/stable/esp32p4/api-reference/peripherals/ppa.html

Basically memory is 2D-DMA, so you can address a block of RGB memory as a 2D rectangle. No need to think about translating X,Y - just tell it to use X,Y,X2,Y2.

This also has optional alpha channels, so 2D bitmaps can be "ARGB" and compositing them together will do transparency effects on the fly.

Sadly it's "just" rectangles and rotations are 90° increments only, but it's quick.

[tulip willow]

This is a 128x64 image sequence of 120 JPEG frames on the USB disk.

At an output of 128x64 it can just decode->display, but at 128x128 it needs to decode->scale->display.

Still pretty quick. Less images is also faster... my original "globe" tests had 900 frames and that seems to bog down the USB Mass Storage stuffs and was running between 30 and 8 FPS. Less frames are running MUCH faster.

[crimson echo]

that is... wow!

Can we have a look at your code? can you share your branch? that is truely awesome. Maybe that can be "merged" with the "GIF image" effect? or this is too specific and tied to the hardware platform? (PPA unfortunately only available on esp32P4...) is this a usermod or in code and use compilation flags?

[latent quarry]

Awesome

[tulip willow]

Absolutely. Share and enjoy.

You'll want the "P4 Experimental" branch here:

https://github.com/troyhacks/WLED

My personal build environment is in the PIO INI file - you'll need PIOArduino to build it tho.

[tulip willow]

It's likely this could be used with devices with SD card support without much changing - just need the SD card stuff initialized elsewhere.

But clearly the PPA stuff won't work on anything except an ESP32.

If you're wanting to build it yourself, please reach out with any questions.

Lots of new stuff today - a little attempt at Resolume-style "video" effects via the PPA

[tulip willow]

PSRAM for caching has really shown it's the USB and the very common "bunch of tiny files" problem found on just about every OS in existence.... that's what is making it "slow".

Move it into PSRAM and it absolutely screams.

[tulip willow]

Now it caches everything - in the background - into PSRAM, keeping 80% free. We have 32MB so that's a LOT of tiny JPEG files.

And also a full set of Transforms which work in real-time.

[latent quarry]

Great job Troy 👍🏻

[tulip willow]

This is all pretty easy as well. The Transforms are all done in the PPA, so anyone can code things that use the PPA in WLED-MM-P4 without much knowledge.

It's very much abstracted by Espressif for ease of use.

What I really wanted was MIDI-over-USB to be working, but right now you can only have High-Speed (USB drives) or Full-Speed devices in use at once.

That's on Espressif's TODO list. 😁

I thought "video" was more interesting.

[golden panther]

Does using a hub in between work? Iirc on some legacy macs running newer unsupported and unpatched macOS versions having a hub was required for working USB 1.1 devices before you install patches

[tulip willow]

There ARE hubs with "Multi-TT" that might be useful, yes. I don't know in which direction - but they are mentioned in the Espressif documentation.

If it moves High-Speed down to Full-Speed that's not as useful.

If it's Full-Speed up to High-Speed that could work?

Hubs do absolutely work with the ESP32-P4. This board actually has a hub chip inside it for all the ports - but it doesn't appear to be the kind that converts things.

Either way, I did find a WaveShare USB hub that claims to have MTT. I'll give it a shot tomorrow. 😁

[golden panther]

The P4 has both host and device USB 2 right?

[tulip willow]

Yes. And both HS and FS controllers.

But only FS or HS can be used in Host Mode at the moment with the IDF v5.5.1. So my stuff is using HS for USB Mass Storage, so that means FS won't init at the same time.

[golden panther]

I know some real midi devices use usb 2 so couldn’t you technically just get another P4 or really any other MCU with USB device 2 and use it for testing until espressif fixes it?

[tulip willow]

Maybe! But then I have two problems - making another device be a working USB-over-MIDI-over-HS device. 🤣

This is the message that pops up on that P4:

E (11001058) HUB: Connected device is FS, transaction translator (TT) is not supported

[tulip willow]

I don't think the USB Host mode will work even with a fancier MTT USB hub now that I read the docs a bit more closely:

"The External Hub Driver: No Transaction Translator layer (No FS/LS Devices support when a Hub is attached to HS Host)."

This doesn't seem like a "to be fixed" - just how it goes.

"ESP32-P4 includes two USB 2.0 OTG peripherals: one High-Speed and one Full-Speed. Both support USB Host functionality. However, due to a current software limitation, only one can operate as a USB Host at a time. Support for dual USB Host operation is planned for a future update."

[golden panther]

Could you use a second P4 to take in midi from a FS device and output it as HS?

Or a P4 + MAX3421E

[tulip willow]

Potentially. You should try this for me. 😁

@golden panther I'm kidding-not-kidding. The ESP32-P4 has been a solo adventure and I'm surprised I've gotten this far.

Any assistance would be extremely welcomed.

[golden panther]

I genuinely do have 2 spare P4 boards and a max chip lol, I just don’t enough experience with c++ and the esp idf

[tulip willow]

THAT HAS NOT STOPPED ME.

Like really. I have no idea what I'm doing.

I have 40-odd years of programming experience, but I've been learning C/C++ for this.

My brain still runs on Commodore 64 BASIC.

@golden panther I was excited to find I had another MIDI controller in my pile of random that's USB-C, but it's still FS, not HS, despite the USB-C connector.

Damn you, backwards protocol and pin compatibility!

@golden panthercome be a developer! You know you wanna.

[golden panther]

I might take a look in a few days once I get the chance but most of my experience is with python and AI doesn’t know shit about the esp32 p4

[tulip willow]

It knows VERY little... but it's still been handy for traditional programming patterns.

Gemini Pro 2.5 hallucinated an entire series of P4-specifc assembly language calls, and then swore on a stack of bibles that it was correct and I was wrong - because those are "not public" - but also that I could just "download" them from... somewhere? 🤣

[golden panther]

Nah you don’t get it Gemini got some major connections in espresif and has enough pull to get instructions added to an existing microcontroller design

[tulip willow]

With the new ImageCacheManager background task pumping away, it's just a random and occasional USB error crash that seems to be Espressif's issue to worry about. I'll finally get to submit an Issue. 😁

[turbid basin]

I was wondering if using MicroSD would change that but looking at the waveshare board, it doesn't have it 😛

Oh no wait it does, on the back 😛

[tulip willow]

Yeah, SD card is on the list as well.

The nice thing about this new ImageCacheManager is that it shouldn't care where you're caching from. I can most certainly extend it to "add multiple paths" so you could be storing and caching from multiple places.

The other thinking is loading configs, presets, LED maps, firmware updates, etc from external storage.

That may mean still keeping a copy on flash as a failsafe, but otherwise you could plug in a USB drive (or SD card) with your config

[turbid basin]

Yeah that's certainly cool. I know in the Chirstmas type of community, being able to play sequences from the SDcard would be a highly sought after feature, but that may be a stretch for now since that requires a lot more.

[tulip willow]

Honestly I don't think it'll be too terribly hard to get SD working.

USB Mass Storage is working, SD should be comparatively simple.

IDFv5 was extremely scary when I started but now it's becoming much more friendly to my brain. I'm seeing the patterns in how everything is being laid out.

Also learning C++ as you go means lots of missteps. 40+ years of programming experience gives me the required programming patterns, but there's still a lot to learn.

I never thought I'd get it this far. 😁

[turbid basin]

Yeah I've been really impressed what you've been able to get working!

[teal fjord]

Can you recommend a P4 dev board for testing? I've been looking at your repo and considering getting hardware to test. Happy to add external level shifters etc, I can solder ok but not hot air.

[tulip willow]

No need to hot air.

This one is good and you can get 26-pin ribbon cables with 26-pin screw terminal breakout boards.

https://www.waveshare.com/esp32-p4-nano.htm

Sadly there's only 15 usable pins on the best side. 😁

This is my general dev board because it has 4 USB-A ports.

https://www.waveshare.com/esp32-p4-module-dev-kit.htm

There's also this version which came out a bit later and I guess has 3.5mm output (sadly not input) and the same 4 USB-A ports. I don't see a difference otherwise.

https://www.waveshare.com/esp32-p4-wifi6-dev-kit.htm

[teal fjord]

Thanks, I'll check those out

[teal fjord]

Is your branch geared around a particular board?

[teal fjord]

Caught my attention for a small PoE board:
https://www.olimex.com/Products/IoT/ESP32-P4/ESP32-P4-DevKit/open-source-hardware

[tulip willow]

Recommend against these ones. The Serial is shared with JTAG. Also no USB-A ports which are needed at the moment for the new Image Sequence Player ("video" player) - which may become actual video files in the near future.

There is an SD slot, but I have not speed tested the SD and there's no support in my code for it yet.

[tulip willow]

Not in particular.

I can confirm the WaveShare ones I listed are the best.

I own just about every P4 board in existence, and those 3 are the ones I recommend.

The Parallel IO system uses hardcoded GPIOs at the moment, but it's entirely possible to ask for every GPIO and it'll just pick the ones not in use.

The nice thing about the P4 is that the pins that are for peripherals are generally hidden. Like you don't need to exclude the camera or display or PSRAM pins, those are not "GPIOs" in the list.

[teal fjord]

Thanks for the detailed explanation, I'll grab a wave share board.

[tulip willow]

Boards NOT to buy;

Espressif's original ESP32-P4 EV board. Beta version of the P4 chip, which has issues.

Wireless-Tag version of the P4 board which actually has an ESP32-C5 on it so it can do 5Ghz WiFi in theory. It's all kinds of weird and the C5 doesn't even have the WiFi firmware (ESP-Hosted) on it. Works fine on Ethernet but doesn't do WiFi because the C5 is barely supported by Espressif at the moment and support didn't exist at all when they made the board. I may support it eventually but it's not correct at the moment. It will also require additional steps that I don't even have instructions for.

...and many of the other P4 boards have some sort of drawbacks or issues during testing. Most work fine for the basics but have different bugs with other things.

⚠️ Also at the moment your WiFi setup is entirely hard coded during build. I need to fix that. There's no SoftAP mode for setup and the wireless setup page in WLED is ignored, even if you get in over Ethernet and change the WiFi credentials.

Both of these are up next for fixes.

I don't recommend using WiFi anyway - this level of power you really want Ethernet. But it'll be fixed in the next few weeks.

[teal fjord]

100% agree, I'm looking at driving 3072 LEDs and the WiFi throughout is definitely causing lag

[tulip willow]

The wifi on the C6 is WiFi6 AX (at 2.4GHz), so it's pretty good.

But it's ESP-Hosted so it's a bit more overhead to talk to the C6 (or C5).

[teal fjord]

It's just the jitter when running DDP to the device, I have a fairly busy WiFi environment and experience has taught me to use wired if I care about any sort of realtime performance.

[turbid basin]

I actually also looked at using the ESP32-C5 in my design I'm working on but next to software support has 0 availability so basing it around the ESP32-C6 for now too. The SDIO implementation should allow for up to about 80Mbit of transfer! Just not sure what extra load all these transfers take on the CPU though.

[tulip willow]

Oh yeah, I run absolutely everything off Ethernet unless it's a particularly "mobile" light, like my Sticks project.

[tulip willow]

The answer is "not much but still a measurable amount".

I noticed a small percentage less FPS when WiFi was just simply enabled. The tasks run at like 25 priority and they don't do much when Ethernet is enabled - but still "some" CPU is eaten. Not a lot, just enough for the tasks. But still any active connection is chatty nowadays.

When you're chasing FPS and A/B testing you can see a slight decrease. Otherwise fine.

[turbid basin]

Right right, that makes sense!

[latent quarry]

Hey @tulip willow ,

Thanks for the awesome project! From the title, I understand that it displays JPEGs from a USB drive. I noticed there’s a “PPA Tester” effect shown in the video, and it seems that the slider is used to select JPEG files — is that correct?

I don’t have a P4 board, but I do have an ESP32-S3 with USB OTG support. Would it be possible to run this project on the ESP32-S3, or is the S3 not powerful enough to handle JPEG decoding and display?

For reference, I’m using a 128×64 HUB75 LED panel.

Thanks again for your work and time!

[tulip willow]

You can't use "high speed" on an S3 so no USB drives - but you can decode JPEGs.

If you have a board with a microSD slot and PSRAM it could be made to work, I think.

Just remember this is also leaning HEAVILY on the P4's acceleration and super fast 32MB of PSRAM.

The next stage is MJPEG files, so you don't need image sequences. That might also speed things up a bit as it's not dealing with tons of tiny files.

[latent quarry]

But. I can use USB thumb drive to otg as storage.

[latent quarry]

Why not GIF? I think it would be much easier. Why is MJPEG better specifically for this project? Can you give me a hint?

Is decoding MJPEGs is easier than GIF .

[tulip willow]

JPEG is hardware accelerated on the P4.

[tulip willow]

I may have been wrong there. The S3 may be supported.

[tulip willow]

Ok, fine... touch screen is working - and the start of a GUI.

Preview is auto scaling (128x64 to 720x360 here) and limited to 30 updates per second. PPA is doing the heavy lifting.

The information bar is drawn every second, and the button bar is displayed if the state changes.

The GUI graphics library is LovyanGFX as they have a nice simple system that doesn't require directly driving a screen and can output RGB888 or ARGB8888 if you need alpha blending. This is very easily integrated with the PPA.

FPS is showing Art-Net output as this box doesn't have any pins - but even without physical outputs, it could make for a very nice WLED remote.

The box is from WaveShare and is meant to be wall-mounted into a standard electrical box. There are also two simple to use relays and even RS-485 if you wanted to use DMX. It can accept any DC power from 6v to 30v via screw terminals on the back, making for a very clean installation.

Audio isn't working yet on this particular model. Same pins, same codec, but they added some echo cancellation thingy that might require a different I2C codec init.

The USB OTG port isn't powered on this device - and I don't know if that's by design or I'm missing something - hence the power injection thing for the USB stick for image loading. It's meant to allow you to use USB-C headphones and charge your phone at the same time, but clearly it works well for any devices. 😁

GUI is also synced to the web interface, so charging in one changes in the other.

[latent quarry]

When I see the USB 🥹

[tulip willow]

The USB is weird on this box - all my other P4 devices have USB-A ports that are powered.

[tulip willow]

MJPEG is mostly to overcome the "many small files" problem. It's easier and faster to load one big file with all the images rather than many small files. This problem is common even on my big beefy desktop.

And yeah, JPEG is hardware accelerated - as I mentioned - but it's also full color rather than a 256-color palette in a GIF.

This is holding all the images in PSRAM (once cached) as compressed JPEG data and decoding them on the fly. Caching takes a while, and I assume MJPEG will be faster..

Not that you can't get good results from GIFs, mind you.

[latent quarry]

I've done some research and the ESP32‑P4: Has dedicated hardware blocks that can decode JPEG and H.264 images/videos directly, which makes image/video processing much faster and less CPU-intensive. It also supports USB OTG, so it can read/write USB devices more efficiently. Not like ESP S3 it's kinda so hard .
I'm still failing to make it work with s3 otg . Even one picture . No idea how to decode . . . I'm still embraced of your project .

I mean 400MHZ is enough

[tulip willow]

There are JPEG decoders for the S3.

[tulip willow]

Presets are labeled. Playlists are a different color. Playlist stays lit so you know you're on a playlist.

Adding or removing presets in the web GUI will update the display - small race bug there, but will be fixed. Currently it paints the main UI before the background loop has painted the UI element, so you don't see the buttons change until you pick a different one.

Everything is dynamic so you can ask for more or less buttons and everything scales. This is compile time options but could be live too.

...like if you only have 7 or 8 presets it could just show one row, etc.

[teal fjord]

On the ESP32-P4, is a different bootloader required Vs the regular ESP32? I have the waveshare P4 nano and whilst I was able to run it with MoonLight, moonlight doesn't fit my use case and the resulting bootloader then failed to boot WLED-MM.
Tried the ESP32 V4 bootloader and it errors out during boot.
Trying to install this version: https://wled-install.github.io/bin_dir/0_Recommended_for_ABC_WLED_Controllers/Troys_experimental_fork_MM_14.5.1/WLED_MM_esp32p4_8MB_ABCVP4-SHIELD-V1.bin

[latent quarry]

@tulip willow i I did it 😄.

[tulip willow]

What is this on? An S3?

[latent quarry]

Yeh

I just understand how it will decode the GIF

[tulip willow]

DM me and we'll see. This is still experimental - but MoonLight P4 and WLED-MM-P4 should be compatible, but I have only installed both from source. 🙂

[latent quarry]

Next Usb Otg .

[teal fjord]

Of course, I can build from source too if that helps. Just wasn't sure which commit to use.

[golden panther]

@tulip willow Is there any way to get around not having support for usb TT on esp32 p4 boards that have a built in usb hub?

[tulip willow]

Not at the moment. You get your choice of USB High Speed or USB Full Speed - but not both.

I have tried various workarounds to no avail, like external hubs, etc.

[tulip willow]

I'd just use whatever is current unless it breaks. 😄

[golden panther]

Does it let you force only FS?

[golden panther]

I've been working on a project that uses the P4's host support to read game controller data but nearly every mainstream controller is USB 2 FS excluding the Google Stadia controller

[tulip willow]

IN THEORY you can force HS or FS.

https://github.com/troyhacks/WLED/blob/3b62a2453e2a966e0c1736859b1db568c1ed26f1/wled00/wled.cpp#L221

But I spent a fuckload of time with my own brain and eyeballs and also Gemini Pro getting to the root of why HS wasn't working.

[tulip willow]

This was my problem with MIDI-over-USB controllers. I wanted something with pads and sliders and stuff (like the APC Mini MK2) but everything is FS - and I also want HS for USB drives.

[golden panther]

So realistically its better to avoid the waveshare p4 boards that have the built in hub if you want both FS/LS and HS devices?

[tulip willow]

No, they are fine. The problem is you can only init USB-Host in FS xor HS mode.

The P4 has "controllers" for both, but you cannot init them at the same time - currently, at least. It's on the roadmap.

[tulip willow]

"ESP32-S3 and ESP32-S2 support USB 2.0 OTG (supporting full-speed mode), and both support Host and Device functions."

So no USB drives on the S3 unfortunately, unless you can find one that works in full-speed mode - there may be some.... somewhere. Very old models. I do not own any.

Contrary to the term "full speed", it's actually slower than "high speed". 🤣

Your best bet would be to use the MicroSD card slot on many S3 boards.

[golden panther]

does wled.cpp in your fork have the code to force only FS or HS?

[tulip willow]

It forces HS, that was harder to do.

It's around this line: https://github.com/troyhacks/WLED/blob/3b62a2453e2a966e0c1736859b1db568c1ed26f1/wled00/wled.cpp#L221

[tulip willow]

So I was vastly wrong about using the microSD slot on the ESP32-P4 at least... it's WAAAAY faster than USB OTG with a USB drive.

Also MJPEG files are now supported in Image Player so it's even more efficient as it can load one big blob.

@latent quarry this means in theory Image Player can be ported to devices with SD card slots - you'll just need PSRAM and a JPEG decoder library. MJPEG is decoded within the image cache manager so no extra libs.

@golden panther this also means because nearly every ESP32-P4 has a microSD card slot (I own 99% of them and they all have microSD slots), I can start experimenting with using it in "Full Speed" mode, so controllers can now be a possibility.

[latent quarry]

S3 only

[tulip willow]

Ability to work with non-uniform Art-Net setups now. Even save and load presets for your Art-Net setups depending on what you're doing.

Also a LOT of bugs fixed for weird sized panels. I was getting away with a few things as everything was 64-bit aligned entirely by accident.

Now everything is 64-bit aligned intentionally. Always. 😁

Also full support for Pioneer Pro Link networks to pull all kinds of data from your decks - including phrasing data for triggering preset changes on exact beats.

Also access to both BPM and beat/bar data.

[latent quarry]

Yoo Tory every time your panel getting bigger 😂🌟 i like it

[tulip willow]

This is 98,304 pixels, 384x256

Most things run around 24 FPS.

The Pioneer DJ demo "effect" needs a lot of pixels tho. It will just default to Solid if you're under 128 in either dimension.

[latent quarry]

Damn that's a lot of pixel

That amount of pixels 24 FPS is crazy

I'm switching to raspberry pi

“I’m learning about Raspberry Pi

But since you using p4 I think it can handle it so will .

[tulip willow]

Well, there's other paths to the Pioneer data without needing that effect.

Scrolling Text has new combinable macros for all the Pioneer metadata so you can make a segment called "#TT - #TA" which will give you "Track Title - Track Artist"

This is great in "overlay" mode so you can have song data overlayed on effects.

[latent quarry]

As always dude you're the legend 🌟.

[latent quarry]

How is that 24 FPS it is so smooth .

[tulip willow]

You'll notice the percentage hit 99.9% and the effect changes.

That's live phrasing data from the decks.

It even recognizes "fill" which the MM Mascot does.

[latent quarry]

Dude that's genius .

[tulip willow]

That's all pulled from the decks - assuming you use "phrase analysis" on your files, Pioneer embeds this.

WLED-MM-P4 pretends to be a CDJ/XDJ player on the Pioneer network so it can grab all the data same as another player could.

Heck, it could even download songs from decks.

I have a vague idea of recording timecode and other values so in theory you could "record a mix" - or at least the data stream of a mix.

Then a custom plugin could read that and your USB stick and bring the entire set into a DAW for fixes.

Here the P4 is also using line-in from the board @coral sinew built for the P4 Nano boards, so I guess if you really wanted to, it could also be an actual mix/field recorder too. We're sampling the music already.

Would need to move up from our 22050Hz sampling rate tho. 🤣

Particle Effects are now running as well. I modified @remote temple 's system so the PPA dumps the PS framebuffer directly to my display framebuffer, which is about 2x faster than setPixelColor on every pixel.

Remapping is a post-process now, so you don't need to worry about it - everything in WLED-MM-P4 is drawn on a flat framebuffer so you can directly access pixel data, use the PPA, do direct memory copies, moves, fills, etc.

It's also now "aware" that the bus needs to be big enough for every pixel, so that's adjusted automatically in case you fuck up, or you want to run a smaller display.

Regular effects and accelerated 2D framebuffer effects run side by side, even as different layers.

And the live preview is now simply taking the framebuffer and scaling it down. Stupidly fast for the live preview - which I now run scaled to the resolution - so here it's running at maybe 5 FPS where it might run at 30 FPS on a 64x64 matrix.

[tulip willow]

A little "quality of life" enhancement too.

LED map names are now used everywhere (in the main GUI and in making presets)

And if you have a bunch of generic presets without an LED map specified, they will load the "default" map (ie, most likely no map) when you click them by default.

The little "Lock" checkbox is persistent across reboots (provided you save your config at some point) and always forces that LED map to be applied, regardless of if the preset has "unchanged" or a different map set.

This is useful if you have a setup where you want to run generic presets in different locations or on different fixtures without making presets for each map.

[teal fjord]

@tulip willow can you recommend a particular make of hub75 panel? I see a lot of requirements for the library but most panels don't advertise the ICs used. Thanks.

[tulip willow]

This is NOT done via the library - all of these panels are driven off a ColorLight card.

Those cards are setup via the ColorLight software and they can run a wizard that can figure out just about any panel setup.

[teal fjord]

How are you driving the colorlight card from WLED? Also, any specific colorlight model?

[tulip willow]

Not exactly.

The path is WLED-MM-P4 -> DDP output (or Art-Net or E1.31) -> FPP/Falcon Player on an RPi5 -> ColorLight Card

For this amount of pixels, DDP has an edge for sure - and WLED-MM-P4 has better optimized DDP.

It may be possible to drive a ColorLight card directly from WLED-MM-P4 but it would require WiFi+Ethernet and that's bad for performance at scale.

[teal fjord]

Hmmm. Seems strange to use the P4 when the solution already requires a RPi5 with so many more resources, but I guess it's fun to tinker!

[tulip willow]

You're not wrong. This was just an easy path to driving a bunch of HUB75 panels without the overhead.

HUB75 video walls have dedicated scaler hardware - so this is basically the same.

I'm looking at MIPI DSI -> HDMI for exactly this reason.

Offloading LED processing to something else is highly useful at scale - this is why I use Art-Net hardware for my huge installations.

...or in this case, a RPi5 as a bridge/

[teal fjord]

I was wondering what approach to take for a modest set of a few 128x128 tiles built up from 128x64 or 64x64 panels and was veering towards putting an ESP32-P4 on a 128x128 block and seeing if I could build up multiples of those into a larger wall. My install space is into a book shelf system which lends itself to modular tiles in terms of the layout.

[tulip willow]

I've done six 64x64 HUB75 panels on an ESP32-S3, so eventually, WLED-MM-P4 will be able to, too. And likely more.

ParallelIO on the ESP32-P4 actually has Espressif demo code for HUB75 driving.

[teal fjord]

That's good news, I saw some conservative memory calculations but 128x128 should be stable in this case. The space allows for 128x128 with P2.5 panels but maybe more if I can find cheap P1.86 or denser displays.

[tulip willow]

I mean, I'm maintaining memory for 384x256 right now and it's running at 24 FPS pretty stable.

That's more constrained by network on the P4 than anything else.

[teal fjord]

I have a digi-octa running 32x96 ws2812b matrixes but 29fps on those wasn't enough to get smooth music response for my eyes, so I'm wary about going too large.

That's 1024 LEDs per output, meant to rewire to 512 each over holidays but stuff got in the way

60fps would be nice I think.

[tulip willow]

Art-Net offload (or this HUB75 offload I'm doing via FPP) is useful as it's giving the pixel pushing over to dedicated hardware.

The Art-Net FPGA devices DO. NOT. GLITCH.

Also WLED-MM-P4 can output up to 16 pins directly so you could drive each of those twelve 16x16 panels at 130 FPS - and Parallel IO at that count is "guaranteed" glitch-free. Up to ~340 pixels x 16 outputs is one Parallel IO transaction and is ensured to be sent perfectly via hardware acceleration.

[teal fjord]

Would be nice if there was a 16 input level shifter board available. I considered using 16 single ws2812b LEDs near the gpio pins as a hack for 5V data levels but it might not work correctly.

I have another 4 panels ready for installation so I can get a 16x16 on each of the 16 pins for a total 64x64 ws2812b array. That'd be fun but I've been dreading the wiring and installation work. Got to get it done!

[turbid basin]

ws2812b is a horrible level-shifter, it's a tiny tiny integrated IC, not resistors on the output, etc. etc. only meant to drive the next LED right next to it. If you have to use some kind of LED, use a ws2811 for instance, nice big chip, decent output drive, pixels often have integrated resistors, etc.

[turbid basin]

So up to 600 LEDs per output pin is problematic then? Reading into what you are saying here.

[tulip willow]

It's been very stable for me, but I think there's a bug in the IDF that causes a slight pause and occasional glitches.

I haven't tested it in a while - when I say "guarenteed glitch-free" I mean there's basically no way 16 x 340 LEDs will glitch - not that more is super glitchy or anything.

and 8 x 680 won't. And so on down the powers of 2.

[tulip willow]

@coral sinew has one for sale! I have one on my desk. Even has I2S line-line! (but you lose 1 output pin when you use I2S line-in, I seem to recall)

[remote temple]

if the P4 DMA works anything like the one on the C3 you could up that number to infinite using linked DMA lists

[coral sinew]

16 outputs if Line-In is used, but 14 if integrated micro. New version will not have this limitation.

[tulip willow]

I haven't actually hooked any LEDs up to mine yet - I'm just super happy to have an Art-Net powerhouse with line-in and Ethernet.

It could have zero Physical LED outputs and I'd be happy. 😁

[teal fjord]

Sounds great, please post a link when the new one is ready.

[teal fjord]

I had seen https://shop.myhome-control.de/en/ABC-WLED-ESP32-P4-shield/HW10027 but was looking for something that handled power as well as data like the stackable power + data boards in my QuinLED Dig-Octa.

As with 5V matrix panels, the amp requirements can be quite high.

Not sure about the mounting holes - this doesn't look vastly different to the hole pattern on the QuinLED Dig-Octa but I bet it wouldn't line up, certainly doesn't include the power-delivery post in the centre of the board.

[turbid basin]

I am working on one that will come out somewhere later this year.

[teal fjord]

Excellent news. I will mess around with the P4 nano and some individual WS2811 as temporary level shifters in the meantime and see how the software develops.

[teal fjord]

Is there a way to upload images via API calls? Would like to display album art but avoid moving to ESPhome and lvgl just to show a 64x64 image.

[teal fjord]

FYI I got up to some fun with Hub75 and album art display on WLED via HA DDP sync and reported over on the MM discord: #1466425745378250846 message

[finite wadi]

Awesome! I'm building a pixel art player for this board! https://github.com/fabkury/p3a

[teal fjord]

Perhaps you could ship the Makapix client as a WLED user mod?
https://github.com/wled/WLED/tree/main/usermods

Would open up your pixel art to anyone with a WLED matrix.

[tulip willow]

@finite wadi you can also use that second USB-C port for a USB drive, but weirdly it doesn't provide power - so you need a powered hub or something.

I have code in WLED-MM-P4 that shows how to init/mount/use a USB HS drive.