How to Upscale a Video
When you’re creating video content and sharing it online, it’s natural to want it to look the best it possibly can. Screens and phones are optimized for high resolution content, and 4K is quickly becoming the new standard across the world. Not all video is formatted in the highest possible resolution however, so what can you do to upgrade lower resolution footage? Well the short answer is ‘a lot’, with a process known as ‘upscaling’.
Hollywood films have been making upscaling video look easy for years, with a simple ‘zoom in and enhance’ effect that hasn’t always been born out in real life, as people are fond of pointing out. The truth is the process is a little more complicated than the movies would have you believe, but with every year that passes advances in video editing technology makes it easier and more effective. In this article we’ll take a look at how upscaling works, and give you some tips on how to upscale your own videos.
In the world of video, upscaling refers to increasing the effective resolution of a piece of content. In other words, converting low resolution material into a higher definition.
It’s important to note that this process will not deliver the same results as a video in its native resolution. For example, upscaling a 1080p video into 4K means taking footage that was originally encoded in 1920×1080 and transforming it into what a higher-resolution version of the same footage ought to look like. This upscaled video will not be identical to a video in native 4K resolution, but it should offer a better clarity and definition than what was previously available.
How does upscaling work
Upscaling takes low resolution content and upgrades it for higher resolutions, using algorithms to ‘predict’ how newly-formed pixels should look. 1080p content, for example, is designed for displays with a little over two million pixels. 4K TVs on the other hand, have almost 8.3 million pixels, while 8K TVs pack in a whopping 33 million pixels. That’s a lot of pixels to account for!
The most straightforward way to fill in those additional pixels is doubling, whereby the same visual information is repeated in blocks of pixels, leading to unrefined block images that are better for retro games than they are for home movies. This is called ‘nearest neighbour resizing’.
Another approach is creating interstitial pixels, which smooth out transitions between pixels in low-res sources. In other words, mid-points that bridge the space between the varying pixels around them. A bright pixel next to a dark pixel in the source video would therefore be bordered by mid-level brightness pixels in the final upscaled footage, which results in a ‘soft’ appearance. This softness can then be improved using sharpening techniques.
What is upscale quality?
Some people mistakenly assume that stretching footage to fit the resolution you're displaying at will deliver the same quality as the original. This is not the case, in fact the greater the jump in upscaling, the more pixels that have to be created, meaning the footage will suffer in quality. In general, upscale quality depends on the quality of the source material. Footage that has been recorded in high definition has a better chance of looking the part when it’s been upscaled to higher resolutions.
Using the upscaling tools that are available today, video can be scaled and optimized for higher resolutions. Currently, it’s not possible to completely ‘restore’ all the missing pixels that you would need to account for to turn 1080p video into true 4K for instance, but with the rate of technological improvement in the world it’s only a matter of time until we can.
If you want to upscale your video content, there is a wide range of NLE software available on the market that can do it for you. Adobe Premiere Pro, iMovie, DaVinci Resolve and Final Cut Pro X are just a sample of the programs that have tools you can use to upscale and enhance your videos.
As well as the NLE options available to you, AI video upscaling is a growing area of the market that can produce some excellent results. AI upscaling specializes in using temporal information to create better video enhancement results than if you were to upscale one frame at a time. This technology is available through software like Topaz Video Enhance AI, and built into some of the newer TVs that are manufactured today.
How does upscaling a video work?
The basic idea of upscaling is taking material in a given resolution - 480i, 720p, 1080p - and stretching it across the entire screen. Without doing this, a 1080p signal would take up just a fraction of a 4K television’s display, for instance. Upscaling algorithms create new pixels to fill the space, using the existing pixels as a reference point. 4K has four times the pixels of 1080p, so to upscale a 1080p video to 4K, each individual 1080p pixel has to ‘produce’ four pixels.
Upscaling a video involves more than just creating new pixels however. Video processing techniques are used to extrapolate what details ought to be present in the scene. How well this works depends on the type of content being upscaled.
Can you upscale 720p to 4K?
The quick and easy way to upscale 720p video to 4K is to scale the video by 535% so that it fills the screen. However, this will not deliver the definition and quality that you would expect from a native 4K video.
With visual effects software like After Effects, you can use effects to upscale 720p to 4K while preserving detail. After Effects has an effect called Detail-preserving Upscale, which you can find in the Effects & Presets section, under the Distort tag. Drag and drop this effect onto your video, and choose Fit to Comp Height in the effect settings and render it out.
Can you upscale a video to 1080p?
These days, 1080p is often the bare minimum expectation when it comes to video resolution online. 1080p is what we call ‘true high definition’, in comparison to 720p, which is merely ‘high definition’.
Upscaling to 1080p means you’re working with source material that’s 720p or lower. In the case of 720p footage, If you upscale the video to 1080p and then change the contrast of colours and apply some sharpening effects and noise reduction using your video editing software you can make small improvements to the video. It's up to you to decide whether it’s worth the effort!
With 480p videos in ‘standard definition’ upscaling becomes a more difficult task, as you’ll see below.
Can I convert 480p to 1080p?
You can rescale standard definition 480p video to high definition 1080p, but this is more like enlarging, and not the same as converting it into HD. When you upscale a video, you’re adding extra pixels based on the information that is provided to you by the source material. Because SD information isn’t anywhere near the level of HD information, there is too much of a gap to make up and you will get varying results.
How good is 4k upscaling
The quality of a video that has been upscaled to 4K will depend on the quality of the source material. For example, if the source material was 720p, it’s impossible for it to ever match the look of an ultra-high quality source like native 4K.
However, that’s not to say that upscaling to 4K can’t be successful. By using external software like Red Giant’s Instant 4K in your NLE, you can achieve great results even from low resolution source material. If you’re playing upscaled 4K footage from 1080p source material on a 4K TV screen it can often be difficult to tell the difference on first look!
For more information on 4K, see our article 4K vs 1080p: A Complete Guide.
One quick way of upscaling video is to use AI video enhancement software. After importing your low resolution video into the software, the program then predicts the missing coefficients and recomposes the same frames with enhanced quality. As well as this, the AI video enhancement software automatically processes the video by deblurring, denoising, sharpening, enhancing and correcting colours and much more.
One of the best AI-assisted video upscalers around is Topaz Labs Video Enhance AI. All users need to do is to add a video and adjust the settings to their liking. The program comes with multiple AI processing models too, which will affect the process differently.
Adobe Premiere Pro is a powerful video editing program that can handle pretty much any video-related task you throw at it. It’s one of the most popular video editors out there, so it’s no surprise that you can use the software to upscale videos by following a few simple steps:
- Create a new sequence. Set the desired resolution, such as 4K or 1080p. Make sure to select the same frame rate and aspect ratio as the original video
- Click into Media from the Preferences menu. Choose Set to frame size in Default Media Scaling in the pop-up window
- Next, import the video you intend to upscale and put it into the timeline. The video should already fill the entire frame, no matter the resolution you’re upscaling to
- Zoom in to the upscaled video to see whether there are artefacts or noise that you need to get rid of. If you want to sharpen the video, apply an Unsharp Mask to compensate for the blurred frames.
- Export the video.
How do I increase the resolution of a video in Premiere Pro?
Premiere Pro handles resolution on a sequence-by-sequence basis. Every sequence you create has its own resolution.
If you need to change a specific sequence to a different resolution, head into the Sequence Settings. Or, select all, copy, then make a new sequence with the desired resolution, and paste your edit into it. Be careful though; if you make the resolution too small you might end up cropping your video.
You can also choose your resolution in Media Encoder, which will encode your entire video at the final resolution you want.
How do you upscale a video from 720p to 1080p in Premiere?
One way you can upscale a video from 720p to 1080p in Premiere Pro is to simply let the software take care of it. By this we mean, select a start and end point for your footage in the timeline, and export it using ctrl/cmd + m.
Once you’re in the Export Settings panel, you can go into the Preset dropdown menu and select High Quality 1080p HD, or another suitable 1080p option. Make sure Render at Maximum Depth is selected, and that the Bitrate Encoding is set to VBR, 2 pass for maximum render quality. Hit Export, and your 720p video will be upscaled to 1080p.
How do I sharpen a video in Premiere Pro?
Once you have your footage imported into a sequence in Premiere Pro, go over to the effects bar on the left and type ‘Unsharp mask’. You should find it in Video Effects > Blur & Sharpen.
Drag the Unsharp Mask onto your video layer, and in the top left of Premiere you’ll see options to adjust settings for the mask. The intensity of the effect is controlled by Amount, and a max setting of 500 here will cause your footage to look unnaturally sharpened. The Radius setting controls the contrast of the effect, and again, a high setting will cause your footage to look artificial.
The ideal settings for the Unsharp Mask are to keep the Amount lower than 100, and the Radius lower than 10. Keep it subtle and you’ll get great results!
So, if you’ve got video content in low resolution that you want to improve, try upscaling it using the tips and techniques we outlined above. You might not get the exact same results as you would if you’d shot the footage in a higher resolution, but you might be surprised at what you can achieve. For more video editing guides, stay tuned to the Video Production section of our blog.