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Gyroflow: Advanced open-source gyro-assisted video stabilization

gyroflow.xyz

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Re: Gyroflow: Advanced open-source gyro-assisted video stabilization

#3
This is actually really cool from a code perspective, as this is the first app I've seen that uses Qt/QML in combination with Rust. I was always searching for alternative cross-platform GUI toolkits that use Rust and some form of QML like language for the UI. sixtyfps (now slint) is a promising candidate that is developed by some ex Qt guys, but their QML style syntax is still a bit off in my taste.

[1] https://github.com/slint-ui/slint

Re: Gyroflow: Advanced open-source gyro-assisted video stabilization

#5
Does the gyro really give much extra information that can't be inferred from the video feed itself?

The complexity of simultaneously capturing the gyro output and time syncing it to the video seems pretty high if the benefit is only marginal.

Re: Gyroflow: Advanced open-source gyro-assisted video stabilization

#7

I use this regularly, with good results. Here’s an example comparison of flight footage from a RunCam 5 Orange on a 5” freestyle quadcopter: https://youtu.be/1ZORzfJ1sog

It does a really good job! Thanks for posting an example.

One decision that such a program needs to make is how to smooth out the movement, and what this one seems to be doing is a sort of a "piecewise linear" function which is a bit jarring to watch when it suddenly transitions between 2 speeds.

Re: Gyroflow: Advanced open-source gyro-assisted video stabilization

#8

Does the gyro really give much extra information that can't be inferred from the video feed itself? The complexity of simultaneously capturing the gyro output and time syncing it to the video seems pretty high if the benefit is only marginal.

I remember a colleague working on such a project about 7 years ago (he put together a prototype in 2 weeks). The reason the gyro makes a huge difference is that the image is not produced at the same time, the sensor rows are scanned out gradually, and a gyro allows you to assign a correction to each row of pixels instead only to the whole image at the same time. Doing the same through vision is close to impossible.

edit: A gyro-based algorithm is quite simple, while computer vision is still not a fully solved problem in general

Re: Gyroflow: Advanced open-source gyro-assisted video stabilization

#9

I use this regularly, with good results. Here’s an example comparison of flight footage from a RunCam 5 Orange on a 5” freestyle quadcopter: https://youtu.be/1ZORzfJ1sog

It does a really good job! Thanks for posting an example. One decision that such a program needs to make is how to smooth out the movement, and what this one seems to be doing is a sort of a "piecewise linear" function which is a bit jarring to watch when it suddenly transitions between 2 speeds.

> One thing that such a program needs to make is how to smooth out the movement

There are several different smoothing algorithms that you can choose from - I don’t recall the name of the one I used here, but it was specifically called out in the docs to be most suitable for acrobatic flight.

You can set up key frames, which can give a lot more control over where and how the stabilization is applied. I just used the ones that gyroflow chose for me here.

> what this one seems to be doing is a sort of a "piecewise linear" function which is a bit jarring to watch when it suddenly transitions between 2 speeds.

I made this example specifically to learn how to stabilize that kind of footage, because that’s what I do the most of and that’s where I think I’ll find the biggest benefit.

Also… this is my favorite quadcopter at the moment, and can do some pretty crazy stuff. It’s got 5x5x3 props, 1,950KV motors, and uses 6S batteries. Assuming 24V and no load, that’s around 47,000 RPM. I don’t have a GPS receiver on it, but I’ve handily outrun a friend’s flying wing that was moving at 120MPH according to its onboard telemetry. All of that is to say that a lot of that speed transition isn’t an artifact of the stabilization. :)

For slow, “cinematic” footage, Premier and DaVinci Resolve’s image-based stabilization does an adequate job with less work.

Re: Gyroflow: Advanced open-source gyro-assisted video stabilization

#10

Does the gyro really give much extra information that can't be inferred from the video feed itself? The complexity of simultaneously capturing the gyro output and time syncing it to the video seems pretty high if the benefit is only marginal.

Definitely.

Syncing “blackbox logs” from the flight controller’s gyroscope is a pain, for sure. There are some cameras on the market now that have their own gyroscope and automatically produce sidecar files for the same time period as the video, like the RunCam 5 Orange. For those, syncing the gyro readings is totally a non-issue.

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