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by Doub
Tue Feb 04, 2020 7:07 pm
Forum: Advanced users
Topic: 1440x1440 HDMI timings
Replies: 10
Views: 493

Re: 1440x1440 HDMI timings

It seems hdmi_pixel_freq_limit was the key to unlock the synchronization. After that for a while I had these weird graphic glitches most of the time while my camera MMAL pipeline was running (the framebuffer console was fine): it was stable (not frozen) maybe 1 second every 5 seconds. It turns out I...
by Doub
Tue Feb 04, 2020 1:31 pm
Forum: Advanced users
Topic: 1440x1440 HDMI timings
Replies: 10
Views: 493

Re: 1440x1440 HDMI timings

aBUGSworstnightmare wrote:
Tue Feb 04, 2020 1:15 pm
buy a Pi4 and connect it to your display ... easiest solution to this issue.
I have size constraints that won't fit a Pi 4, and I need an unlocked camera port, so that's not really a solution.
by Doub
Mon Feb 03, 2020 3:14 am
Forum: Advanced users
Topic: 1440x1440 HDMI timings
Replies: 10
Views: 493

Re: 1440x1440 HDMI timings

For Pi0-3, the default max pixel frequency through the HDMI is 148.5MHz as the hardware is specified for 1080p60. Would the Pi4 be able to run at higher frequencies safely? If so is there a compute module in the pipe using its SoC? Your pixel frequency of 198MHz is above that, so the mode is consid...
by Doub
Sat Feb 01, 2020 6:47 am
Forum: Advanced users
Topic: 1440x1440 HDMI timings
Replies: 10
Views: 493

Re: 1440x1440 HDMI timings

For reference the full edidparser output is as follows: Enabling fuzzy format match... Parsing edid-1440x1440.bin... HDMI:EDID version 1.3, 1 extensions, unknown aspect ratio HDMI:EDID features - videodef 0x80 !standby !suspend !active off; colour encoding:RGB444|YCbCr422; sRGB is not default colour...
by Doub
Sat Feb 01, 2020 6:47 am
Forum: Advanced users
Topic: 1440x1440 HDMI timings
Replies: 10
Views: 493

1440x1440 HDMI timings

I purchased a small 3" 1440x1440 LCD panel for a head mounted display project. It's MIPI DSI but it came with an HDMI adapter board, which is detected properly on a Windows PC. 1440x1440 is the same number of pixels as 1920x1080, so I assume the Pi can do it, but tell me if I'm wrong. On my Pi (a CM...
by Doub
Tue Dec 17, 2019 8:05 pm
Forum: Beginners
Topic: New Tenda W311MI USB WiFi Dongle
Replies: 1
Views: 1059

Re: New Tenda W311MI USB WiFi Dongle

I have a similar dongle branded Cudy. On a Windows 10 I did the same as what usb_modeswitch does, which is to eject the virtual CD from the default mode. It then re-enumerates with that same Realtek 0xB711 PID, and some (preinstalled or automatically downloaded) Realtek driver matches the device and...
by Doub
Mon Nov 25, 2019 6:39 am
Forum: Networking and servers
Topic: WiFi dongle list & capabilities
Replies: 0
Views: 142

WiFi dongle list & capabilities

I've started a project using a Pi Zero W and I successfully managed to get its WiFi to work in combined managed+ap mode, ie. WiFi client and access point at the same time. Now I'd like to move the project to a compute module (I currently have a CM3+ and I/O board, custom I/O board on the way), and I...
by Doub
Mon Nov 25, 2019 2:40 am
Forum: Troubleshooting
Topic: (UPDATE) Drivers for TL-WN725N V2 - 3.6.11+ -> 4.xx.xx+
Replies: 1430
Views: 1357316

Re: (UPDATE) Drivers for TL-WN725N V2 - 3.6.11+ -> 4.xx.xx+

The install script linked in the top post doesn't seem to support the Pi compute modules. Is that on purpose? I have a CM3+ and a TP-Link RTL8188EUS-based Wifi dongle I'd like to use together. I had to add the following section to get the Pi detected: # check for Pi CM3+ elif cat Pirevno | grep -i '...
by Doub
Thu Aug 29, 2019 4:36 am
Forum: Camera board
Topic: Is a power switch possible
Replies: 3
Views: 577

Re: Is a power switch possible

HermannSW wrote:
Mon Jul 22, 2019 6:44 pm
Hot plugging camera does not work, needs to be present at boot.
Would it be possible to boot with it, then unplug it temporarily and re-plug it when necessary?
by Doub
Wed Jul 31, 2019 1:28 pm
Forum: Graphics programming
Topic: Screen capture and video encoding
Replies: 5
Views: 1777

Re: Screen capture and video encoding

Thanks for the pointers. It looks like it might be possible through the dispmanx API. I need to spend some time with it (and MMAL) to see if I can manage to get an uncompressed video stream efficiently and encode it. I have not used MMAL extensively for encoding, my main focus has been getting the c...
by Doub
Tue Jul 30, 2019 8:31 pm
Forum: Graphics programming
Topic: Screen capture and video encoding
Replies: 5
Views: 1777

Re: Screen capture and video encoding

You can start with VNC direct capture mode, which can obtain legacy OpenVG or dispmanx overlay pixels directly from the framebuffer. This sounds quite inefficient to run a VNC server and a VNC client just to capture the framebuffer. Do you happen to know how that direct capture mode is implemented?...
by Doub
Wed Jul 17, 2019 4:56 am
Forum: Graphics programming
Topic: Screen capture and video encoding
Replies: 5
Views: 1777

Screen capture and video encoding

I've written a C application which primary feature is to display the camera input full screen, with some UI overlay, with minimal lag. I've used MMAL to capture the camera, and OpenVG to draw the overlay. Now I'd like to add as a secondary feature (as in, it shouldn't compromise the primary feature)...
by Doub
Wed Jul 03, 2019 9:05 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Trying to connect a LCD display to a raspberry pi 3 B+
Replies: 6
Views: 799

Re: Trying to connect a LCD display to a raspberry pi 3 B+

Did you just buy a random LCD panel and assume you could connect it to a Pi? Or did you pick it from a list of compatible ones?
by Doub
Tue Apr 16, 2019 12:33 pm
Forum: Camera board
Topic: Why no 4-lane CSI on the Zero?
Replies: 2
Views: 403

Why no 4-lane CSI on the Zero?

The Raspberry Pi Zero CSI connector has the same pinout as the compute module IO board CSI connectors, but two of the four CSI data lanes are not connected. I always assumed it was because the BCM2835 didn't have a 4-lane CSI input. But I just realized the compute module v1.1 does have a 4-lane CSI ...
by Doub
Tue Apr 16, 2019 11:56 am
Forum: Camera board
Topic: Disabling lens shading
Replies: 3
Views: 387

Re: Disabling lens shading

I did find the second link but not the first. Thanks.

Interestingly (at least to me), the red tint on the edges is even worse without lens shading. So I probably need to customize it instead of turning it off. But that's work for a later stage of the project.
by Doub
Tue Apr 16, 2019 7:12 am
Forum: Camera board
Topic: Disabling lens shading
Replies: 3
Views: 387

Disabling lens shading

My project puts a naked IMX219 sensor in a focal plane of a scavenged telescopic lens. I noticed I get some unexpected red tint near the edges of the image, and some greenish gray tint near the middle. I'm wondering if that comes from the lens shading step of the camera pipeline. I see the MMAL_PARA...
by Doub
Tue Apr 16, 2019 7:01 am
Forum: Camera board
Topic: MMAL cropping
Replies: 5
Views: 509

Re: MMAL cropping

The calculations are all buried in the firmware. Is "firmware" stuff provided by Broadcom or by the Raspberry Pi Foundation? Is it likely to evolve and improve if I suggest non-breaking changes? It'll first take the sensor mode and centre crop it I don't want the centre, but instead select a square...
by Doub
Mon Apr 15, 2019 1:56 am
Forum: Other projects
Topic: Target Camera for Long Range Shooting - Intrigued?
Replies: 5
Views: 1816

Re: Target Camera for Long Range Shooting - Intrigued?

I've been working on putting a Pi Zero in my scope instead of on the target. I don't need the long range radio, but I have the same dual "at home with internet" and "at the range" problem. I found out that with the built-in Pi Zero W WiFi I can have it both as a WiFi client and an access point at th...
by Doub
Mon Apr 15, 2019 1:27 am
Forum: Camera board
Topic: MMAL cropping
Replies: 5
Views: 509

Re: MMAL cropping

Well, I don't need to record video (yet), but I need the preview to work. I managed to get something to work by changing the pixel aspect ratio (format.es.video.num/den) of the camera preview port. I feel like there's way too many scaling steps in this pipeline when all I want is stream pixels 1 for...
by Doub
Sun Apr 14, 2019 4:27 am
Forum: Camera board
Topic: MMAL cropping
Replies: 5
Views: 509

MMAL cropping

In my application I need only a square portion of the camera image, and 60 fps. So I'm running a camera v2 in mode 6, which gives me 1280x720 pixels. I'd like to only get 720x720 pixels, but choose which ones (aligned left, middle, right or anywhere in between). I've been playing with the camera com...
by Doub
Sat Apr 06, 2019 1:03 am
Forum: Camera board
Topic: How to make pi camera display stays in front of other windows
Replies: 2
Views: 440

Re: How to make pi camera display stays in front of other windows

If you "start the camera" using raspivid or similar, you can try to download and compile it from sources, and change the PREVIEW_LAYER in RaspiPreview.h to something higher than 2.
by Doub
Sat Apr 06, 2019 12:57 am
Forum: Camera board
Topic: Change resolution and transfer rate
Replies: 3
Views: 471

Re: Change resolution and transfer rate

As far as I understand the MMAL pipeline which raspivid uses only support the two official cameras, so I'm not sure you can use this to read data from your FPGA, unless it emulates one of the official cameras. I think there are other ways to get the CSI data from Linux without using the MMAL stack, ...
by Doub
Sun Feb 10, 2019 3:04 pm
Forum: Camera board
Topic: segmentation fault on second mmal_port_destroy
Replies: 4
Views: 442

Re: segmentation fault on second mmal_port_destroy

You shouldn't use m_pool after calling destroy. This is C (as oppposed to C++), the mmal_port_pool_destroy function cannot set your pointer to NULL, the caller is responsible for that. This is just like calling "free" twice on the same pointer.
by Doub
Wed Feb 06, 2019 10:11 am
Forum: Camera board
Topic: One camera, 2 preview windows. Is this possible?
Replies: 9
Views: 861

Re: One camera, 2 preview windows. Is this possible?

I think the PiCamera wraps and connect the camera and renderer components. What you need is insert a splitter and add a second renderer. You probably need to go one level deeper into the MMAL binding and connect the components yourself. Maybe get the sources for the PiCamera class and modify it to s...
by Doub
Fri Feb 01, 2019 9:16 pm
Forum: Camera board
Topic: Camera V2.1 not (or no longer) working on Pi Zero W
Replies: 4
Views: 898

Re: Camera V2.1 not (or no longer) working on Pi Zero W

What is the output of "vcgencmd get_camera" with v2 camera connected? Here is what I get with one of the non-working V2 cameras. [email protected]:~ $ vcgencmd get_camera supported=1 detected=1 [email protected]:~ $ raspivid -f mmal: mmal_vc_component_enable: failed to enable component: ENOSPC mmal: camera com...

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