Hardware Switcher Information

[Steven Digges]

There is already a lot of discussion in this forum about software switching so I am going to try and be helpful by starting a thread on hardware switchers. The shows I do range from small where I am a SPC doing it all to shows with AV budgets well into six figures. The switching I do is not just for webcasting. It is usually done with a live audience in the venue viewing camera I-mag, computer feeds, and video content. The switched program signal is often webcast live or used in post-production to eliminate countless hours of multi-cam editing. Unfortunately, these days the small shows are more common than the big budget shows. On complex shows I do not run the switch or any other gear, I am the technical director. I don’t want to sound like an authority on this but it is something I know a little bit about so I will help if I can.

Hardware Switcher Basics: For the purpose of this thread I will assume you are webcasting or interested in it and you want to do it in the most economical way you can. There is a lot of good news if that is your objective. Switchers are just like cameras and computers in the sense that they have gotten better, smaller, and less expensive. The bang for the buck is amazing. For over a decade I hauled a Sony Anycast AWS-G500 all over the country, what a PIA. That switcher cost me $18,000.00. Last month Roland released the Roland VR-4HD HD AV Mixer for $2,800.00 and it does almost everything my Anycast did and some of it better. And you might not even need that level of switcher, there are more economical options.

As soon as you begin multi-source webcasting your system will become switcher centric. Switching can be done with a dedicated hardware device, software, or combination of both. Question number one is what are your sources and their method of connection? Will they remain constant or do you need to be prepared for a multitude of devices and signals. If you are building a system just for your own sources and that will not change you are lucky and will get by spending much less. In my scenario I have to be prepared to handle whatever device a presenter may give me ten minutes before he goes on stage. That is not the way to run a show and they have all been told they cannot do that but it happens all the time. We used to be concerned with just PC or Mac, now they might give me anything under the sun right down to their damn phone. This matters because it is all going to be fed to the switch! So…..what are your sources, connections and your output signal specs? Are they all cameras or will you be switching to computer signals, tablets, and phones? Can every source send exactly the same resolution and frame rate signal in? Does that signal match your output signal? Matched signals can matter a lot.

Scaling, this means everything. To understand what switcher will work for your needs you need to understand scaling. Hardware switchers have a scaler on every input, no scalers, or some scalers. Simply put, most switchers with no scaled inputs will require every input signal to be exactly the same resolution and frame rate or they will not work. Scaled inputs allow you to use unmatched signals and convert them to a uniform match. To seamlessly switch digital video signals they all need to be the same and the conversion happens on the upstream side of the switch, hence the need for scaled inputs. Scaled inputs dramatically add to the cost of switchers. If you are sure you don’t need them don’t pay for them, but know you are limiting your input signal versatility. Having at least one scaled input is a very good thing to have.

Decimator to the rescue: Just a few months ago Charles Papert mentioned the Decimator line of converters to me. They make a line of independent scaler/converter boxes. I chose the MD-Cross HDMI-SDI Up/Down Cross converter. It is an amazing little box. I can program it to take almost any signal I want and output that signal as almost anything I want. It can turn any unscaled input into a scaled input. That means you may be able to combine a switcher with unscaled inputs with a decimator ($400.00) and save the money stepping up to what a scaled switcher would cost. For me, it can be a lifesaver because I never know what signal I am going to get from a client and it also serves as a HDMI/SDI cable converter or a SDI distribution amp.

Finally some words about switchers: If I was in the market for a simple webcasting switcher this month there is no doubt in my mind I would go with one of the new Roland Video Mixer/switchers. Over the last year Roland has released a new line of affordable video switchers (they are switchers to me, some call them mixers). You can check out the “V and VR” line here:

https://proav.roland.com/global/cate...ured_products/

The line covers everything from simple 4 input HDMI switchers to Multi SDI/HDMI switcher/mixer/effect processors with a dedicated USB output for webcasting. Some have no scalers and others have some scalers. There is something for everyone. My disclaimer would be that I have very little experience with Roland products. The switchers on most of my shows cost tens of thousands more. If these work as advertised I don’t see how you could beat them.

Black Magic Design: I do not have much good to say here. But admittedly I am not a fan of BMD in the first place. BMD offers the ATEM line of video switchers. One of my gripes is I read their website with cation because it is hyped with what they do and nothing about what they don’t. For example, on first glance they appear to do a lot. They boast about all of the input compatibility of the ATEM line. In reality they accept the standard array of SD and HD video signals. There is not a scaled input available on any of them. All signals will have to match or be externally adapted. They also do not have good built in control surfaces (if any). You have to dedicate a lap top to control them. If you want to buy the optional control surface, even for a $1,000.00 switcher you have to buy the $5,000.00 control surface. They only make one and it works with the whole line. Craziness, every time I think they provide something of value I find what they leave out to lessen the price. I will stop there and leave you to your own opinions.

I knew this would get long. I hope someone finds at least something useful here.

Kind Regards,

Steve

[Donald McPherson]

I've been messing about with Xsplit two cam. I've had to adjust the match frame timing within the program. Say I buy the Roland V-1HD Portable Compact HD Video Switcher does anyone know if I can also frame match. ( say one camera is wired and the second wireless the timing is different)

[Steven Digges]

Donald,

Check out this page:

https://proav.roland.com/global/promos/v-1hd/

Tons of info on the V1-HD. I think it will work for you as long as both cameras are the same resolution. It says for example, that you can mix 1080i and 1080P signals so it must have a frame rate matcher.

The V1-HD is the most basic model but it does a lot. Remember though that it is HDMI out only. The USB is not the USB 3.0 made for webcasting output found on some other models.

Steve

[Chris Harding]

Hi Steve

I think what Donald is taking about is the fact that the wireless unit does have some latency and would that be an issue on a hardware switcher. I actually need to try the same setup on my software switcher and see if there is an issue bringing in a 1080P direct camera and a 1080P wireless remote camera .. if Livestream Studio can do it I'm pretty sure the Roland's firmware can also do it. I know that Studio does an auto downsize to 720P when you bring in video that's 1080 into a 720 project.

[Steven Digges]

As long as the wireless video receivers are outputting a true video signal any switcher wont care where it came from. They will work if it is an accepted resolution.

There is no such thing as adjustments for incoming latency. There is however often times audio delay adjustments to keep audio/video sync.

Steve

[Donald McPherson]

I think I will wait and see if someone else uses this system. I only need two cameras at the moment so will stick with what I know works.

[Giroud Francois]

I like software PC based switchers because they are very open, and allow fast compatibility.
For example Vmix has really tons of features and there is nothing it can't do.

Today, video heavily rely on computer network, as output for streaming or as input for taking source like skype or face book or twitter.

NDI is a new standard that is really handsome (you can transform a smartphone as a mobile camera or a tablette as wireless monitor.

You can record simultaneous streams (at different resolutions or with and without effects for example), you are almost totally free with video format, mixing interlaced with progressive, scale video at will , get input not only from cameras, but also form smartphones or PC.

[Bruce Dempsey]

Cerevo Livewedge is what i use

[William Hohauser]

Originally Posted by Steven Digges

Donald,

Check out this page:

https://proav.roland.com/global/promos/v-1hd/

Tons of info on the V1-HD. I think it will work for you as long as both cameras are the same resolution. It says for example, that you can mix 1080i and 1080P signals so it must have a frame rate matcher.

The V1-HD is the most basic model but it does a lot. Remember though that it is HDMI out only. The USB is not the USB 3.0 made for webcasting output found on some other models.

Steve

I have a decent amount of experience with these switchers and I have to say that for the price you get a lot of switcher in a compact yet easy to use package. The USB on these switchers (including the SDI version) is only for computer control of basic switcher functions and firmware upgrades. To webcast with these switchers you need an HDMI/SDI to USB3 or Thunderbolt convertor.

There are a few caveats I have regarding the HDMI version of these switchers (if the SDI version had been out, I would have gotten those for a specific client). The HDMI latency is very evident and can be disruptive to the switching process if you are doing a live event and can't isolate the switched audio from the live audio. The switcher has an analog audio input but that will be about 5 frames early depending on the HDMI equipment you are using. In my situation it is some robotic cameras from PTZ Optics (very good cameras incidentally but no functional audio input). The Roland switcher allows you to delay the analog audio but it's very hard to get it frame accurate. SDI shouldn't have this problem. I am setting up a weekly live webcast in the near future for a client and to avoid the sync problems I am sending the audio board feed directly into one of the pro JVC cameras being used and letting the HDMI sync itself.

Roland is releasing a newer A/V mixer, the VR4-HD (https://proav.roland.com/global/products/vr-4hd/) that has an integrated audio mixer, a preview monitor and USB3 video feed for a computer but lacks the traditional two banks with fader bar functionality of the V1-HD or V1-SDI. It's also significantly more expensive than the purchase price of a V1-Hd, a Blackmagic HDMI to Thunderbolt convertor and a four input audio board.

Personally if I can't use a Tricaster for a multi-cam live streaming project, I would rather use a Roland switcher then use a software switch. I would keep the titling in the computer with a program like Wirecast but an actual switching board is easier and less anxiety inducing.

[Donald McPherson]

That answers my question. No video sync only audio sync. For the V-1hd I would need to go cable all the way to make this work? Yes?

[Chris Harding]

Hi Donald

I bring my audio into a mixer and disregard the audio signal coming down the HDMI feed but I must admit I haven't noticed any sync issues at all ...OK I'm not using a hardware mixer but we do use the main camera on wireless coming into the software mixer LS Studio and then bring all audio feeds directly into the computer. Is the issue only with hardware mixers or do software mixers correct the latency so audio/video sync is correct. According to William's post if the incoming video (assuming it's just video you are switching) you have a 5ms latency so audio fed directly into your streaming software would be out of sync by that amount? I'm confused as even on closeups I don't seem to have any lip sync issues that I can see anyway!

[Charles Papert]

Couple of notes--Steven noted above the good results he'd gotten using the $395 Decimator MD-Cross for input format conversion. Thought it was worth mentioning that Decimator makes a similar unit for $295, the MD-HX, which omits the test pattern generator but has the same scaling engine.

For my application I use a Blackmagic ATEM Television Studio which as Steven notes does require all inputs to be the same format (their recently released version does accommodate many more formats the original version, but still has that uniform requirement). And indeed it does require a laptop if you don't want to use their full sized hardware component. I've augmented with an X-Keys stick which works well for cuts-only switching. Any function of the ATEM that can be controlled with a keystroke can be mapped to the X-Keys, which are quite affordable.

[Donald McPherson]

I don't have a hardware mixer. I am asking about two cameras one HDMI to USB/converter the other HDMI /wifi sender to wifi receiver/HDMI to USB/converer. There is an obvious lag between the two which can be synchronised in X split. As said above you can adjust the audio but not the video to sync.

[Charles Papert]

Donald, the solution to this may lay in the wireless transmitter you are using--if it is encoding to H264 that would likely be the cause of the delay. There are many zero latency transmitters on the market that can help with this.

[William Hohauser]

Any HDMI source will gain a delay every time it's put thru a device. So for example, I have an HDMI source that goes thru a recorder then loops to the Roland switcher then the switcher output signal goes thru a recorder and then finally out of the recorder to a HDMI monitor. So that's 4 HDMI devices the signal loops thru. By the time I see the signal on the monitor it's a number of frames late from the action I am recording. I could use an HDMI DA but then I need more monitors to make sure everything is working. In another set up I have Sony consumer camcorders running HDMI to the Roland switcher and there might be a frame delay versus the analog input.

A wireless transmitter will put a delay in and the receiver will put in a delay depending on the transmission method.