RACE MODE for Walksnail Avatar: Image Quality and Latency Testing

hi there everyone today we're going to be talking about a new feature coming down the line from walks now for the Avatar HD system this is race mode walks now are doing what DJI couldn't or more likely wouldn't do which is create a mode specifically for their HD system designed for fpv racing in this video we're going to be looking at the image quality and the latency of race mode and we're going to be talking about the consistency of latency that walks now is attempting to achieve with this new setup so let's not waste any more time let's dive right into it so let's start by enabling race mode and seeing what changes in the Avatar system so jump into the menu of the Avatar system and then go into the settings page in the settings page you're going to find the device submenu and within that menu you're going to find race mode when you enable race mode the goggles are going to need to reboot and then you'll notice a few changes firstly when you come to select your channels you see the channels are labeled R1 to R8 those are all the raceband channels so you're going to be using exactly the same frequencies as analog video on those raceband channels the second thing you're going to notice is that you're going to be locked to 25 megabit mode and that's to maintain that 20 megahertz Channel bandwidth that's equivalent to analog so that you're not using up more bandwidth than an analog pilot on that same channel and the third thing you're going to notice that's changed is that the resolution will now be 540p rather than 720P so it makes sense in race mode why walk Snail would change the frequency of the system to precisely match the analog raceband channels and also why they'd lock Us in 25 megabit mode so that we're using a 20 megahertz wide Channel equivalent to an analog pilot but why are they changing the resolution of the system from 720p to 540p well this is a trade-off that they're making to improve the consistency of the latency of the link in that racing mode whenever we're transmitting data over the air we have to trade off signal strength bandwidth and effective data rate with the Avatar system when we're flying freestyle we turn the transmitter power up as high as we can and we run the 50 megabit mode with the wide bandwidth so 40 megahertz wide Channel and that gives us the best possible effective data rate so that's the best image quality and the lowest possible latency however in a racing situation we can't do that in racing we're limited to 25 milliwatts of output power and a 20 megahertz wide channel so that we play nicely with all of the other pilots who are flying different systems and that really limits the effective data rate that the Avatar system has to play with the walkstown Avatar system a reduction in the effective data rate can directly impact the latency the way the system works is it encodes each frame of video and then transmits it to the goggles the goggles needs all of that data all of that encoded data to be able to reconstruct the frame and so if any of that data is missing because the signal was weak or because there was interference that data has to be re-transmitted from the VTX to the goggles and then once all the data is there the goggle can decode the frame and display it so the Avatar system has some buffer in its transmission protocol for a certain amount of re-transmission however if the signal is very weak or there's a lot of interference there might be so much loss of data that and so many re-transmissions needed that it just takes too long and the re-transmissions overrun the amount of time allocated for them if that happens then the system has no choice it needs all the data to be able to display the frame and so it keeps re-transmitting and so you get an increase in latency it takes longer for the frame to arrive with the race mode what walks now done is they've reduced the resolution to 540p that's reduced the amount of data that needs to be transmitted and that means that now there's more space in the in the transmission pipeline there's more time for re-transmissions and that means that the system can deal with more interference or a weaker signal before there's an impact on latency there still will be an impact on latency if the signal gets very bad but the hope is that this is a very rare occurrence and that most of the time you're going to see a very consistent 25 milliseconds or so of latency but how is all this going to affect image quality and latency in race mode well to answer that we're going to look at some flight footage now and this flight footage was collected with pre-release firmware so please take the results with a big grain of salt because performance is going to change on this system before it's released as further development happens but nonetheless we can see the difference between 720p standard mode and 540p race mode we'll start by looking at 720p at full output power so this is really best case scenario we're 50 megabits so that 40 megahertz wide Channel 720p 100 frames per second and we're at full output power maximum output power and so this is kind of The Benchmark for image quality that I think we're all used to seeing when we're flying freestyle with the walks now Avatar system but now let's switch to 720p 100 frames per second but now we're going to use a 20 megahertz wide channel so that's 25 megabit mode and we're also going to switch down to 25 milliwatts output power and now we can really start to see a difference in terms of the image quality between you know full output power 50 megabit mode and this 25 megabit mode 25 mil output power it's really a lot less stable in terms of latency and the image quality also is not so consistent now let's look at 540p race mode so this is 540p 100 frames per second still 25 milliwatts output power still 25 megabit mode so 20 megahertz wide Channel overall I definitely think the image quality is a little bit worse than 720p full output power 50 megabit mode definitely but I think the image quality is a little bit more consistent a little bit more stable in this race mode compared to standard mode at 25 milliwatts and I think also the latency is more consistent more stable at 25 milliwatts than what we get in standard mode so this race mode is doing what you know walks now wanted to do which is improving the stability the consistency of the the image quality and the latency in that low output power narrow channel bandwidth situation that we have in fpv racing with latency being such an important consideration for racing I wouldn't want you to just believe the latency numbers reported in the Avatar goggles without any evidence to back it up so I'm going to take you through my latency test setup that uses a thousand frames per second high speed camera and then we're going to look at some high speed footage and measure the latency of the Avatar system in this new race mode all right so let me take you through my latency testing setup if you haven't seen it already I have two LEDs here wired up to a single switch so they both turn on and off at exactly the same time and LEDs turn on and off really really fast in a few nanoseconds a few billionths of a second so these LEDs are instantaneously on and off together over here I've got my fpv goggles with a high speed camera pointed into the goggles looking at the goggle screen and I don't use a GoPro for this I use a different high speed camera in fact it's the camera you're watching me through right now but this GoPro will kind of serve the purpose it's looking at the goggle screen and that's where the high speed camera is looking I take one of the LEDs and I put it so that it's visible from the high speed camera and I take the second LED and I put it in front of the fpv camera so if you think about the view from the high speed camera it can see one led directly in front of its lens and it can see the other LED through the goggles so like through the fpv system and that means that when I turn on the LEDs they both turn on at the same time but the high speed camera sees the LED in the goggles turn on first and then some number of milliseconds later depending on the latency of the system it will see the LED in front of the fpv camera turn on and using this method we can very accurately measure the glass to glass latency of any fpd video system and we can also measure the time to full frame and the frame rate as well okay so let's look at some high speed footage from this test setup we can see that at time T equals zero both LEDs are turning on and we see the LED in the goggles turn on immediately then we have to wait some time about 25 milliseconds before we start to see the LED turn on in front of the goggles and we can actually see the whole goggle screen update over the next 10 milliseconds and we have a complete new full frame after 35 milliseconds that also tells us that the frame rate of the system is 100 frames per second because we're getting a new frame every 10 milliseconds so how does this latency compare with other systems well as you can see in this chart race mode is very comparable to the other modes that the Avatar system has under the best case conditions and it's very competitive with the latency offered by any of the DJI systems either DJI V1 or O3 it's not quite as fast as the systems from HD 0 or analog fpv and so that's something to bear in mind if you're a very competitive racer looking for the lowest possible latency so that brings us to the end of the video and as always it's time for my conclusions and even though this is pre-release firmware and there's still a bit of work to do on it before it's finished I already love what this says about the direction that calyx is going with the walkstown Avatar system because for me walks out Avatar has always been about having a digital fpv system that can do a whole load of different things really well so it can do micros you've got that 1s light VTX you can do five inch freestyle with the right antennas you can go really far with the system because it's no range limit on it so you can do all of these different disciplines but before now you couldn't really do racing racing you still needed to fly analog or hd0 another system but if walksdale can get this race mode working really really well then you could theoretically use walks now avatar for every different type of quad that you wanted to fly and I think that's brilliant that's that would be a fantastic place for the system to be as a better value option it's cheaper than O3 so you get slightly better value and you can do more things with it so you don't have to have multiple different fpv systems for different applications for different drones that you want to fly that's where I think this system will really shine and there's just one other thing one other thing that walks now could do that I think would be really brilliant to kind of continue on this line walks now if you can do a flight controller that has an elrs receiver and a walks out Avatar VTX built into it so it's a single board solution for tiny whoops then I think that would be amazing and then walks to Avatar you really could use it for everything because you could have race mode for tiny root racing and you could have that onboard recording if you wanted to uh to record your tiny with flights as well in much better quality than you could achieve with uh with an analog system for example so those are my conclusions and if you enjoyed the video and you got value out of the time that I put into doing the flight testing and the latency testing and going through how to set up race mode on the system then please consider joining my patreon you can join from just a few dollars a month it will support the time that I put into making all these videos and help me make better videos for you in the future you'll also get access to a special area of my Discord server and sneak peeks of new upcoming products and boy is there a new upcoming product that you're going to want to know about coming very very soon so if you'd like to join that there are links down in the video description I'd really appreciate it that's all I have for you for today so until next time I wish you all very very happy flying

Channel: Chris Rosser

Views: 6,562

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Id: O9iuNx8eXss

Length: 12min 42sec (762 seconds)

Published: Mon Sep 04 2023