Redmi smartphone owners often face a situation where when viewing video content, the image does not occupy the entire usable area of the display. This is especially true for the Xiaomi Redmi 9 model, whose screen has a specific aspect ratio of 20:9. Many videos shot in the classic 16:9 format are displayed by default with black fields at the top and bottom, which visually reduces the play area.
But today’s technology allows you to stretch a picture or use smart zooming to tap into each matrix pickle. In this article, we’ll take a look at how to make full-screen video on a Xiaomi Redmi 9, look at the built-in MIUI system, settings for popular players, and how to adjust your social media display, and learn how to get rid of annoying streaks and enjoy content at maximum resolution.
It's worth noting that not all methods are suitable for any type of content, for example, stretching a news broadcast can distort the faces of announcers, whereas for animations or abstract videos it will be invisible, so it's important to understand the difference between full-fill mode and smart zoom mode to choose the best option for a particular situation.
Technical features of the Redmi 9 display and aspect ratio
To properly customize the display, you need to understand the physical basis of the device. The Redmi 9 screen has a resolution of 2340×1080 pixels, which corresponds to an elongated format of 20:9. Most video content on the Internet and television is still produced in the 16:9 standard (Full HD).
The default Android system in the MIUI shell is to keep the original proportions of the video in order not to distort the picture. It's the right behavior in terms of the director's intent, but not always convenient for the user who wants to maximize the image. Understanding this difference in proportions is the key to solving the problem.
⚠️ Attention: Forced stretching of video can cause geometric distortion of objects. Circles can become ovals, and people's faces can stretch unnaturally wide.
There are several ways to address this imbalance: you can use built-in galleries, third-party video players with powerful rendering engines, or system settings for specific applications. Each method has its advantages and disadvantages, which we will discuss later.
Use of the built-in video player Xiaomi
The standard video app preinstalled on Redmi 9 has hidden zooming features that not everyone knows about. It automatically analyzes content, but lets you manually switch display modes during playback, the fastest way to change a picture without installing additional software.
To activate full-screen mode, run the video file through the gallery or file manager. At the bottom of the screen or in the settings menu (three dots), find the icon responsible for proportions. It usually looks like two triangles diverging to the sides, or is indicated as a ratio.
Click on this control several times to cyclically re-examine the available modes. The system will offer options for Original, Fill and Stretch. Fill clips the edges of the video, removing the black bars, but losing part of the image on the sides. Stretch mode distorts the picture, filling the entire screen completely.
☑️ Checking player settings
When you switch to another video, you can reset to standard settings, so you have to repeat the procedure, which is done for convenience, so that you don't distort the content that you want to show in the original proportions.
Set up full screen mode for YouTube and online cinemas
When you stream content, for example, through a YouTube or Netflix app, the scalability is limited by the service player itself, but at the MIUI level, you can force the app to use the entire display area, ignoring the camera cutout or standard indentations.
To do this, you need to go to the system settings. Open Settings, find the Advanced Settings section (or just scroll down to Full Screen Mode). This is a list of all the installed applications. Find your browser or movie theater app in the list and activate the switch.
Once enabled, the app will ignore system constraints and stretch across the entire physical matrix, which is especially useful for browsers where video players often don’t adapt to the elongated screens of Redmi smartphones.
| Annex | Recommended treatment | Possible distortions | Impact on the battery |
|---|---|---|---|
| YouTube | Standard + Full-screen | Minimum | Average. |
| Browser (Chrome) | Forced full screen | Possible at the interface | High. |
| gallery | Automatic. | Depends on the file. | Low. |
| TikTok / Instagram | Native (vertical) | Absent. | High. |
Keep in mind that enabling full screen mode for some applications can cause interface elements (Back buttons, status bar) to be superimposed on the video, in which case it is better to go back to standard settings.
Why can’t you just stretch a video on YouTube?
Third-party video players for maximum control
If Redmi 9’s standard tools aren’t enough, Google Play’s dedicated apps are on the rise, with MX Player, VLC for Android, and KMPlayer leading the way, and with powerful decoding engines and flexible zooming settings.
The most popular solution is the MX Player, which uses a simple gesture to control the scale: double-touching the screen in different parts changes the display mode, which is much more convenient than looking for buttons on the menu every time.
Available modes in third-party players usually include:
- 📐 Original - retains the proportions of the source, leaving black fields.
- 🔍 Scaling – zooms in to fill the width or height of the screen, cutting off the excess.
- ↔️ Stretching – forcefully fits video into the screen boundaries, distorting geometry.
- 🎬 100% – displaying a pixel to a pixel without interpolation.
Using a third-party player also often solves problems with playing heavy formats that Xiaomi's built-in gallery may not "pull" or display with audio desynchronization.For owners of Redmi 9, this is a great opportunity to improve the content consumption experience.
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In the MX Player, you can configure the double tap action in the gesture settings. Set "Scale" for the left edge and "Stretch" for the right to switch between modes instantly.
Addressing blackband issues on social media
Social media platforms like Instagram, TikTok and Telegram dictate their display rules. Vertical videos (9:16) take up the entire Redmi 9 screen without any problems, as they are even narrower than the phone's display.
In Telegram, for example, the built-in player allows you to do a pinch-to-zoom zoom, so by diagonally spreading two fingers on the screen, you can zoom in by removing the black bars, but losing some of the image at the edges, which is the safest method, without causing geometric distortion.
On Instagram, the situation is similar. However, if you use the web version through a browser, you may need to activate the system full-screen mode, which was discussed earlier. The mobile application usually adapts itself to the screen, but when you rotate the device, you can experience crashes.
⚠️ Note: When watching video in messengers through the built-in player, the quality may decrease due to traffic compression. For better quality, download the file and open it in a third-party player.
Some users try to use modified versions of the applications for advanced features, but on Redmi 9 this can lead to unstable system operation or locking the account.
Frequent questions and solutions to scaling problems
Even after setting up, you may have questions about how Android works on MediaTek processors installed in Redmi 9. For example, video may twitch when stretching is enabled if GPU resources are not enough.
If you notice that the phone starts to heat up or video slows down when using full-screen mode in heavy formats (4K, HDR), try to reduce the quality of playback in the settings of the video service itself.
It’s also worth checking for system updates. Xiaomi engineers regularly release patches that improve the display and video subsystem. Go to Settings → About Phone → MIUI version and click the update check button.
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The optimal balance between quality and screen filling is achieved by using Crop mode rather than Strettch, as this preserves the natural proportions of objects.
In conclusion, video size management on Xiaomi Redmi 9 is a flexible process that depends on your preferences: someone is willing to sacrifice the edges of the frame for the absence of black stripes, and someone prefers the original picture. Using a combination of system settings and third-party players, you can customize the device perfectly for yourself.