View Full Version : Zero budget wireless video links


Andrew Smith
August 11th, 2022, 09:10 PM
In recent months I tried something new for a camera link at an event where you have a few cams around a stage but there is a street march component in the middle of the proceedings and you really need to include this in the coverage for the live stream.

YouTube has such good streaming infrastructure and 4G cellular data coverage works everywhere, and it would be such a shame for the facility of these to go to waste. :-) So we tried using a smart phone with the YouTube Studio app to stream horizontal video to a non-public location, in turn fed into the video switcher and through to the official live stream.

The technical test prior to the event worked well, so it was a very promising thing.

Knowing the importance of good audio, we obtained a Rode VideoMic Me (https://rode.com/en/microphones/mobile/videomic-me-c) which gives stunning quality audio for what it is. Pro-tip: there are three versions of this product according to the connector on our phone and you need to purchase the one that matches the handset you will be using on the day. Also, the mic clamps are designed for the width of the phone and you will need to remove any protective covers to attach it.

The mic did surprisingly well at picking up the voices of people you interview along the way and rejecting the unwanted environmental noise. The clarity of the audio really brings something special to the content.

When using the phone as your remote camera, a phone stick could come in handy but you otherwise just have to hold the thing and move smoothly like a video ninja (as you do) as you make your way amongst the people.

The good news is that the quality of your video footage on the phone screen is absolutely stunning. The bad news is that the YouTube app is a liar. Per the attached image, the video quality really falls apart as if it had defaulted down to 360p resolution. With no comms between you and the video switcher, there is no way to discover this until you make it back. Ugh.

Andrew

Andrew Smith
August 11th, 2022, 09:20 PM
The initial diagnosis of the situation was that the YouTube app will drop down its data rate to maintain a stream, sacrificing resolution along the way, to survive patches of bad reception. Further, that as a domestic app and not professional software it simply doesn't even bother to check resume a better quality stream later on.

We did some further testing and the conclusion is that the YouTube app encodes out just enough of a data rate to support a good rendition of a face talking to the camera, but anything more than that and the image quality will rapidly fall apart. Possibly to save the drain on a battery and working within the limitations of phone CPUs when the app was developed.

Take a look at the attached image of the shoe which serves as a "simple" image for testing purposes. You can then compare to the quality of the two wide shots.

Essentially, YouTube streamed from a phone just isn't up to the task.

Andrew

PS. Click the images to enlarge them.

Andrew Smith
August 11th, 2022, 09:33 PM
During our subsequent testing and evaluation, we also tried a Facebook live stream. Whilst only 720p resolution, the quality of the video streamed was clearly superior to that of YouTube. I don't have an example frame to show you, but we'll try with this option for the next time we do this.

I wouldn't be surprised if the day comes where software for professional use is developed for the purpose of doing this sort of thing. You might have to stick with some minimum spec phone hardware, but we've been through this before with the early days of ingesting and editing video on a computer. Sure beats lugging around a camera, power source and proper streaming hardware to do the same job.

Andrew

Greg Miller
September 3rd, 2022, 06:27 AM
That has been the case with a lot of low-BW video systems ever since day one. I recall the same sort of issues using the original hardware-based PictureTel system 25 years ago. A medium shot of seated talent, against a stationary, rather plain, background, was fine. The more you deviated from that description, the worse the video got.

I've often wished I could tell a video system to drop back to 15FPS or even 10FPS, while maintaining spatial resolution. Personal preference, perhaps, but I would rather watch a quick sequence of visibly discrete frames, all sharp, rather than a smooth stream of blurry, low-res video.

It will be interesting to hear how well Facebook streaming works for you. I wonder whether the cellular network cuts back on your BW when there are a zillion people on site, all talking and texting at once. Any chance you could set up your own router & outdoor hotspot on a private LAN, and have the phone/cam connect directly to that.