Video: Video Engineering Toolbox: The Last Two Feet, Part 1
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David Hassoun: Let's dig into some of the last two feet. So the ultimate goal here is, how do you actually see this stuff all come together? Wat goes on on the screen? Hopefully this is a no-brainer, but VLC Player is a great player for testing, just to see how things work.
It doesn't give you a whole ton of insights, but it's a good baseline to make sure, "Hey, if it plays here, you're probably pretty good." The tricky thing with VLC player is I've seen it play a lot of things that other players can't handle. It's a little bit too good in that regard, so as a user, if you want to use it, that's great for you. This is not something that normally happens. Most times it's video engineers, and you're using that to validate and test and so forth.
Is it a great litmus to test, to say, "Okay, well, if it plays in VLC it should play anywhere"? No. Unfortunately not. It's a very resilient player that does a good job working around issues for the most part. But it is a good baseline. If it doesn't play in VLC player, I can pretty much say it's not going to play almost anywhere, unless it's due to authentication, token issues, that type of stuff. But that's why you use your network tool up front.
Beamr View is a really cool tool. Now, this one is more for comparative quality analysis. Maybe I have two different videos and one's looking to have a problem, but they're supposed to be the same. Especially when you want to compare quality between different bitrates. One of them was having an issue, playback or it's just, "I'm doing encoding and I want to be able to validate stuff."
It is really cool. And it's free. They don't make it sound like it's free when you go to their site, just so you know, but it actually is. You hit them up, you say, "Hey, I want to use this, is that cool?" They're gonna be like, "Yeah. Sure, go for it. As long as you're not doing something you really shouldn't be." They also have really cool, amazing encoding tools that are also, for the most part, free depending on the level of usage that you do.
With Beamr View, it's mostly about A/B and it does frame-by-frame. So you can kick over. You can get indications of data up on top, so what's your resolution. In this case, even though these are separate resolutions, I told it to scale to match so I can see. Then it has a couple different ways that you can look to do. You can see the quality benefit of one versus the other.
There's a number of different ways you can do that. I did split view. There's butterfly view, so it actually flips them over. There's dual view. That's gonna be hard to see. Let's go back to something that's a little more manageable. And there's overlay, that you can toggle for. I'm running at a lower resolution than my computer wants to, so nothing looks great except for if I go back to the split view, which is my favorite, and lets you do the back and forth.
Really handy tool, also good for testing playback as a whole. Does a good job. Also loading in things like HEVC content, it can handle and so forth. So when you want to start looking like, "Okay, really, am I gonna get the benefit of HEVC versus AV1 or H.264, this can be a really good place to start looking to see. And you can see for yourself. You should get a benefit, let's be clear.
One of my personal favorite ones, and the one I use probably the most is Telestream's Switch. It's a paid player, and not a cheap one. Really, the value that you get out of Switch and why they have a fairly hefty price tag on it, is it's meant to also be able to allow you to do key stuff when it comes to fixing things, especially around subtitles, closed caption data and so forth. It's one of the few ones that actually allows you to pull out your 608, 708 data that's in-band and actually do things to it and potentially fix things that we normally couldn't do elsewise.
However, to get the features that I like, which is specific around this nice little bottom bar, you also need to have that same version. Here is actually the Switch player. Also, frame-by-frame. The benefit, and why I love this tool, though, is all these little markers, these are actually showing your iframes, your pframes and your bframes. So the yellow is an indication of your iframes. The pframes are your purple and the blue ones are your bframes.
Why is this important? If we have content, that for instance, doesn't start on a keyframe, bad things happen. Always need that iFrame in the beginning. Or you can have a number of issues that can come forward from that. One of the first things I always have to do is go check, what's our keyframe? Let alone, also, is our keyframe cadenced properly? If we have a keyframe every two seconds, making sure that that happens and follows through as that can cause issues in certain platforms, especially when you start switching between content.
But then you can also see, there's also additional keyframes. Those are gonna be on scene change, most likely. So see complete scene change and then this is our two-second cadence. So we can have extra ones, but we need to always make sure we have our cadence that we want. The weird thing that I've seen as well, and I still have yet to be able to really get this one locked down, is oftentimes I see a lot of times in Switch where it shows a blank keyframe in the beginning. But other tools that I use, so if I go do some stuff like ffprobe or whatnot, it won't indicate that there's an extra keyframe there.
I still love this because it's a super-valuable tool and it has actually helped me identify a lot of problems in the past, especially when we're trying to do intermixed content. When it comes to potential encoding issues, or packaging. So if something gets cut and packaged improperly, this is a great visual tool to allow me to actually see that.
Also, if we're seeing playback and we're seeing bad things happening in the video, bad blocking and so forth, coming in, being able to play it here frame-by-frame, really handy. But it does have its downsides, specifically around its cost.
RealEyes CEO David Hassoun discusses more playback-testing tools, including RealEyes MOE:Viewer, in this clip from his presentation at Video Engineering Summit at Streaming Media West 2018.
RealEyes CEO David Hassoun discusses Elecard Stream Analyzer, FFprobe, and other tools for deep content analysis in this clip from his presentation at Video Engineering Summit at Streaming Media West 2018.
RealEyes CEO David Hassoun discusses Charles, Wireshark, Apple TV Proxy, and other network diagnostic tools in this clip from his presentation at Video Engineering Summit at Streaming Media West 2018.
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