Raspberry Pi Forums

dividuum

Hi. I've managed a basic MMAL based video playback on a DRM GL surface on the Pi4. I've now run into an odd issue that I don't have any explanation for. Have a look at this image: https://usercontent.infobeamer.com/mmal-video-render-flickering.jpg Edit: Here's a video . What you see in screen captur...

dividuum

Two threads, each independently wait on a drmModePageFlip for their respective display? Not at the moment. Is that how it's supposed to work? Right now I eglSwapBuffers, then gbm_surface_lock_front_buffer, optionally create a drm fb from if none exists yet and then issue two drmModePageFlip calls f...

dividuum

Another day and a few follow up comments and questions. modetest is the lowest level DRM test tool. "modetest -M vc4" for my single headed display lists [...] Thanks for that. That makes it easier to see what's going on. I don't believe there is any guarantee that the displays will be in sync, and t...

dividuum

Hey. Thanks a lot for the quick response and very useful insight. I'll see how far I get

dividuum

I'm currently porting info-beamer pi to the Pi4. I'm using DRM to set up a GL surface without using X at all. A few questions came up while working on that: When is /dev/dri/card0 and when is /dev/dri/card1 active? Usually it's card1, but I remember seeing card0 successfully working as well. Are the...

dividuum

Thanks for the pointers. It looks like it might be possible through the dispmanx API. At least from my understanding (of up to the Pi3, no idea about what the Pi4 might do at some point), there's no way to efficiently get any kind of realtime screen capturing. The vc_dispmanx_snapshot function resu...

dividuum

DeluxePixel wrote: ↑
Mon Jul 01, 2019 10:28 am
More to the point, is it possible on the pi4 to use any form of accelerated opengl without using X?

A simple yes or no from someone who knows would be great.

Yes. With the mechanism from my previous post. No X required.

dividuum

Not quite, EGL is still used, its dispmanx that has been replaced by X11 as the lower layer. You need to be able to provide and Xwindow id to eglCreateWindowSurface rather than a EGL_DISPMANX_WINDOW_T Not necessarily: You can also use DRM/GBM(?). See this code (run with ./kmscube -D /dev/dri/card1)...

dividuum

Is there any good documentation on DRM and all the other APIs that are used now? https://01.org/linuxgraphics/gfx-docs/drm/gpu/index.html seems to document the driver side point of view. Even the man pages link to non-existing documentation pages (for example drmModePageFlip). Only somewhat complete...

dividuum

Edited: The H264 decoder only supports 1920x1080. Oh. Didn't know that. Thanks. So HVEC is required for that? How does one decode that? I naively modified my existing code to send HVEC video frames to the `video_decode` component and never got a OMX_EventPortSettingsChanged event. Is OMX still supp...

dividuum

How exactly does that work? Can we the existing OpenMAX API? I tried omxplayer with jellyfish-120-mbps-4k-uhd-h264.mkv from http://jell.yfish.us/ without success: root@raspberrypi:~# ffprobe jellyfish-120-mbps-4k-uhd-h264.mkv ffprobe version 4.1.3-1+rpt1 Copyright (c) 2007-2019 the FFmpeg developers...

dividuum

dom wrote: ↑
Fri Jun 28, 2019 1:37 pm
But a simpler source might be kmscube.

Thanks a lot. That was exactly what I was looking for. That should be very helpful in porting my code over to the Pi4.

dividuum

X isn't essential. Kodi for example runs as a fullscreen app. Any hint where to look at? I guess this is the GBM part? Is there any minimal example that shows how to set up a GL surface similar to how it worked with the legacy drivers? When opening a surface like that, I guess that's still on its o...

dividuum

info-beamer can do that. It has the option to render videos on OpenGL textures. So you can use all kinds of transformations. The downside is that this is more GPU intensive and FullHD might be problematic. The feature is used for example in this magic video wall package to arbitrarily transform vid...

dividuum

Paul Hutch wrote: ↑
Tue Apr 02, 2019 5:55 pm
From what I've read nobody who has coded this type of system for the Raspberry Pi has released it as free software.

While I'm guilty of that too, the following exists and might be what OP is looking for: https://github.com/balena-io/wifi-connect

dividuum

How to sync different videos on differents Raspberry? If you're ok with using a commercial product, our info-beamer hosted product can do that. You can easily build video walls or individual screens that play either the same content or different content of the same duration in sync. info-beamer wor...

dividuum

There's also this readme that describes how to write(?) some OTP values. No idea if that's helpful and I didn't try any of the mentioned commands. Proceed with care.

dividuum

Info Beamer looks interesting, yes I would really like a turn key solution with start and stop times to control the media players. Unfortunately I think your solution David is rather out of my budget as it has more commercial features than I require as a poor Artist. info-beamer is really on the lo...

dividuum

Thanks for the suggestions, very helpful, I have looked at the Pi Wall before which is interesting. [...] Mike what is SSH ? I’m not much of a programmer If you're willing to trade money for convenience, you can look at our info-beamer hosted digital signage solution . It can do what you describe e...

dividuum

Thanks for the replay Is same thing it play 2 sec then freeze 1 sec and then stop I trying to stream this video to a Raspberry Pi https://www.youtube.com/watch?v=RtU_mdL2vBM I'm the developer of info-beamer hosted , a digital signage system for the RPi. I've been playing around with live streaming ...

dividuum

Hi there - I have a wall mounted TV in a corridor I use to display welcome information etc. The TV has no ethernet port, just HDMI in. I used to drive this via a PC the other side of the wall but I now want to use a spare Raspberry Pi I have kicking about. There's an ethernet port on the wall behin...

dividuum

True seamless will be hard to do with a rpi just based on the processing power. That's not correct. My info-beamer pi software is capable of that. It works by preloading and pausing the next video before the current video ends. Once it ends, it unpauses the next video. It works pretty well. Here's ...

dividuum

I doubt you'll get useful feedback if you don't post at least some of your code.

dividuum

There is the hdmi_adjust_clock vcgencmd command that can be used to adjust the output HDMI clock frequency. There's a post somewhere in this forum that describes that using a slightly increased or decreased framerate is still within the HDMI spec. I've using this in info-beamer pi to create the "glo...

dividuum

Hi, ,this is exactly what I'm looking to do but I need the process embedded into my Raspberry Pi Zero W .. do you offer a non-hosted solution? Sorry, I don't. Also it's tightly integrated into the custom Linux distribution that info-beamer hosted is using, so it wouldn't work in Raspbian without qu...

Search found 225 matches

Pi4: MMAL video in GL (on DRM). Flickering texture. Any idea what might be wrong?

Re: Pi4 DRM questions

Re: Pi4 DRM questions

Re: Pi4 DRM questions

Pi4 DRM questions

Re: Screen capture and video encoding

Re: OpenGL on Buster on both Pi 3 and Pi 4

Re: OpenGL on Buster on both Pi 3 and Pi 4

Re: OpenGL on Buster on both Pi 3 and Pi 4

Re: Playing UHD H264

Playing UHD H264

Re: Thread from Pi4 discussion

Re: Thread from Pi4 discussion

Re: could omxplayer display non rectangular area ?

Re: WiFi Connection manager with fallback web configuration portal

Re: How synchronize videos on Raspberry CM3 ?

Re: Writing to OTP registers without rebooting

Re: Multiple displays running simultaneously

Re: Multiple displays running simultaneously

Re: use omxplayer to streaming youtube

Re: Info display screen

Re: RANDOM VIDEO PLAYER FOR ART INSTALATION

Re: Trouble rendering a simple OpenGL ES 2.0 application

Re: Possible to adjust phase of frame timing on video output?

Re: RPi configred as Access Point to configure Wifi?