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14 votes

Raspberry Pi 3 has less than 1GB memory available at OS level

If the output of vcgencmd get_mem arm && vcgencmd get_mem gpu is arm=880M gpu=128M This means that GPU is using 128M. This can be verified/changed in raspi-config Advanced Options, although ...
Milliways's user avatar
  • 60.3k
10 votes
Accepted

Raspberry Pi 3 has less than 1GB memory available at OS level

First of all, I give my best regards to @Milliways for suggesting to check 2 simple commands. vcgencmd get_mem arm && vcgencmd get_mem gpu Where is the missing 128MB memory? Even if both ...
vaha's user avatar
  • 1,240
9 votes

Can I use the GPU for calculations?

You can write high-level programs that run on the Pi's GPU using QPULib: https://github.com/mn416/QPULib It's a programming language and compiler targeting the 12 vector processors (QPUs) inside the ...
user46562's user avatar
9 votes

How am I supposed to set GPU memory in RPi4?

Here's the relevant part of the official docs. Min and max: GPU memory in megabytes, sets the memory split between the CPU and GPU; the CPU gets the remaining memory. The minimum value is 16; the ...
Dmitry Grigoryev's user avatar
8 votes
Accepted

WebGL does not work properly on Raspberry Pi Chromium Browser

Okay so I found a solution here: https://www.raspberrypi.org/forums/viewtopic.php?t=191087 use raspi-config to enable OpenGL (Full KMS) remove "--disable-gpu-compositing'' from /etc/chromium-...
JoeyCK's user avatar
  • 708
5 votes

Unable to set GPU memory split on Raspberry Pi Zero W

Thanks to the forums over on raspberrypi.org I was able to find out the answer to this, so I am sharing it here for future reference... ANSWER: The 128M of GPU RAM is still being reserved because I ...
MrChips's user avatar
  • 983
5 votes
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300 MHz (3D core) / 400 MHz (VideoCore IV) difference?

The article is referencing two different circuits within the GPU that are meant to take two different tasks. Does this mean the GPU has 700 MHz raw power? No, the things don't just plug into each ...
Jacobm001's user avatar
  • 11.9k
5 votes
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Using GPU to decode QRCODE

In theory, you could use the OpenGL API to speed things up a bit. There's no implementation of OpenCL for now. You could design your code such that its calculations are a fragment shader according to ...
Aloha's user avatar
  • 7,156
5 votes

How to connect a graphic card to Raspberry pi?

I originally flagged this as being, possibly seriously, Off-Topic but technically there is a further method that make it possible to connect a graphics card to the RPi and have the latter generate ...
SlySven's user avatar
  • 3,621
4 votes
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Raspberry PI 3 Increase Gpu Memory to 944

This is useless as you don't seem to run GPU RAM heavy OpenGL applications. You don't need more than 128MB GPU RAM to run videos smoothly as the hardware decoder will use only a fixed amount. So ...
kwasmich's user avatar
  • 2,702
4 votes

Is there a GPU accelerated Xorg server?

Eric Anholt has been working on completely overhauling the Raspberry Graphics Stack since July 2014. This means it was done "properly" - everything is opensource and directly in upstream: kernel.org, ...
flakeshake's user avatar
  • 6,213
4 votes

Get CPU and GPU usage on Raspberry Pi

To monitor the CPU, RAM and SWAP usage in Raspbian, you can use TOP or HTOP. In terminal, run top. TOP is available by default, and gives reasonably good details. But, I find HTOP to be more useful, ...
Dr.Viper's user avatar
  • 209
3 votes

eglGetDisplay() fails on RaspBerry 3

The hello_* programs are built against Raspberry Pi's closed source driver's EGL platform ("dispmanx"). The open source driver doesn't implement that EGL platform, and instead implements EGL on X11, ...
Emma Anholt's user avatar
3 votes

Fatal Error: GLES2/gl2.h: No such file or directory

The file GLES2/gl2.h belongs to the package called libgles2-mesa-dev, which you should install with apt-get.
Dmitry Grigoryev's user avatar
3 votes
Accepted

How will leaving the default GPU memory setting at 64 affect my installed packages

The setting doesn't affect "installed packages" specifically, but affects the amount of memory you have available for graphics operations and how much system RAM you're left with. You need at least ...
cjs's user avatar
  • 833
3 votes

Hardware-accelerated h264 encoding possible?

Looks like by compiling ffmpeg by yourself, on RPi3B+ you can get ENCODING HIGH-COMPLEXITY 30 FPS VIDEO FROM A 1920 X 1080 JPEG IMAGE SEQUENCE – SIGNIFICANT MOTION AND INTRAFRAME DETAIL – HIGH ...
akostadinov's user avatar
3 votes

Why does the Raspberry Pi's GPU control the first stages of the boot process?

The GPU copies a 32K block to the L2 cache and executes it. It saves the cost of a CPU BIOS chip - the 32K code loads it from an SD card The reference manual doesn't say if that 32K is rewritable. If ...
Sean's user avatar
  • 31
3 votes

Get CPU and GPU usage on Raspberry Pi

The command that will give you insight into what's being allocated by the GPU is sudo vcdbg reloc. The output looks like what begins here. In my case, I could see that the 236M allocated was too close ...
OutsourcedGuru's user avatar
3 votes

How am I supposed to set GPU memory in RPi4?

You shouldn't need to set it beyond the default value in the plain Raspbian /boot/config.txt. Max value is 128M. Setting it beyond 128M can leave your Raspberry Pi 4B unbootable. GPU memory on a ...
Dougie's user avatar
  • 5,321
3 votes
Accepted

Hardware acceleration on the pi 4

The foundation has their own (downstream) version of ffmpeg with HEVC decode (!) acceleration: https://github.com/popcornmix/FFmpeg/tree/2711 HEVC acceleration in VLC is currently being beta tested :...
flakeshake's user avatar
  • 6,213
3 votes

RPI 4 - ffmpeg - how to get hardware h.264 decoding to work?

As of July 2021 you can get half way there. There is a V4L2 M2M (memory to memory) interface that is used to access hardware encoders and decoders, and the Pi seems to have pretty good support for ...
Malvineous's user avatar
  • 1,884
2 votes

What is the optimum split of main versus GPU memory?

From my experience, 8-16MB for just terminal. 20MB for 800p GUI 24MB for 1080p GUI 32MB for 1440p GUI 64MB for <1080p youtube videos 128MB for 1080p youtube videos 256MB for 4k videos (more than ...
ProDigit's user avatar
2 votes

Get CPU and GPU usage on Raspberry Pi

This question is old, but the accepted answer does not tell how to monitor the GPU usage. There is a way -- tested only with the closed source broadcom drivers: # /opt/vc/bin/vcdbg reloc stats ...
zertyz's user avatar
  • 741
2 votes
Accepted

Pi 3 GPU overclocking ability

Yes it is possible to overclock the GPU and yes , this leads to a performance improvement. Look at following resources: Official overclocking overview here example config.txt settings here. Please ...
flakeshake's user avatar
  • 6,213
2 votes

Hardware-accelerated h264 encoding possible?

The ffmpeg apt package now includes support for hardware encode and decode. sudo apt install ffmpeg To see which hardware codecs (using one of the following APIs: v4l2m2m, VAAPI, OMX, MMAL) are ...
Pierz's user avatar
  • 844
2 votes

Show multiple HD streams at once on raspberry pi?

Im no expert but I know the Pis network bandwidth isn't super duper, so I'm assuming you'd get away fine with one HD to start from each Pi, then the more videos you cram for a single Pi to render, you'...
mrSidX's user avatar
  • 608
2 votes
Accepted

Compile Raspivid from userland

Compiling raspivid (or any of the raspicam apps) requires a lot more than just RaspiVid.c. Have a look at the top of that file and you'll see it also uses stuff from RaspiCamControl, RaspiPreview, and ...
Dave Jones's user avatar
  • 3,978
2 votes

WebGL does not work properly on Raspberry Pi Chromium Browser

Seems like your not the only one with this problem. You might wanna check your chrome://flash page , and see if you are using any drivers that you shouldn't. Test and check each driver accordingly for ...
Aden's user avatar
  • 80
2 votes
Accepted

Can Raspbery Pi 4 hardware decode 4k@60hz H.265 10bit video?

According to this document, it actually supports "HEVCv2 Main 4:4:4 10", where the 10 at the end means that it actually supports 10 bit decoding, which also hints it might support HDR.
lvella's user avatar
  • 189
2 votes

Getting OpenGL ES Framebuffer back to CPU Memory

glReadPixels() is the correct function to use, and it's exactly what you asked for: Move data from the GPU's framebuffer to the CPU. On Raspbian, I believe they disabled the NEON code in the GL ...
Emma Anholt's user avatar

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