Typical Nerd: YouTube Video Quality - Resolution Dependance

If you’re one of those guys or girls that share their video gameplay on YouTube as a Let’s Play then you are probably very interested in how good the video looks once uploaded to and processed by YouTube. YouTube encodes every video you throw at it, every single one, in order to have it in all the available resolutions and, more importantly, in a format that can be streamed and displayed by their web video player. With another step of encoding being done, a step where you have no control over, a lot of quality is getting lost because of the rather low bitrates YouTube chooses, especially for modern games that are visually very complex. How can you get around that?

I’m not going into all the details that comprise video recording and encoding of gameplay. I merely compare what influence the video resolution has on the quality of the resulting video on YouTube.

Of course, your source should be of a high quality. What does high mean? In the best event lossless, of course, but who has the time to upload 60 – 70 GB of video for about 20 minutes of gameplay. So you compress it first, at the moment H264 should be the video codec of choice for most gamers, and the upload it. If possible, select an application or custom workflow that utilizes the x264 encoder. It produces the best quality by far. The downside: it’s purely CPU drive so you need as much cores as possible. But, in my tests evaluating a video editing software, it was still the fastest compared to the MainConcept encoder without hardware acceleration (which didn’t work with my GTX970; could be an issue of Sony Movie Studio that I tested). Also you should prefer a constant rate factor (CRF) over variable bitrate (VBR) because that lets the encoder decide how much bitrate to use based on the source material. This way you don’t have to tune the setting for each and every game or use a too high bitrate range for games that don’t need it. I recommend a CRF of about 20 or 21. That produces a video that is as close to lossless as possible in a decent amount of time (running on a 3.8 GHz 6-core monster). For my videos I use TMPGEnc Video Mastering Works 6 which comes with the x264 encoder but uses a percent based rate factor instead of what x264 usually uses (which seems rather random to me, but hey, those guys are smarter than me so there must be a reason). I set that value to 64% which is somewhere around CRF20.

Enough of that now, let’s get to the actual topic: the influence of the resolution. This one I can make very short. If you record Full-HD, i.e. 1920x1080 you should consider scaling to at least 2048x1152. It adds a very tiny bit of blur or jagged edges on some texts but regarding YouTube it is totally worth it. From my comparisons it looks like, and I have read that in forums as well, YouTube uses the quality setting of the 1440p resolution which gives you a much better quality. Following are a set of images of two games recorded in 1080p and uploaded in 1080p, 1152p and also 1440p (the latter two scaled from Full-HD). Here are the links to the respective videos.

Now the screenshots taken from the YouTube web player on a Full-HD monitor. 1440p might look better on a higher resolution display but on a 1080p monitor I can see no difference to 1152p.

Batman Image 1: 1080