Xiaomi smartphone owners often face the need to quickly send a copy of a document, whether for visa processing, registration on a government service website or verification of identity at a bank. Instead of finding a printer and a scanner, modern technology allows you to turn your device’s camera into a powerful tool for digitization.
The challenge is not just pressing the down button, but preparing the image to be accepted by government agencies or financial institutions. The camera must work in a certain mode to remove glare, align perspective and improve readability. In this article, we will explore all the nuances of working with built-in tools of the MIUI system and third-party solutions.
You'll learn how to avoid common bugs like blurred corners or lack of contrast. We'll also look at Mi Scanner's built-in app, which is often underrated by users, even though it's perfectly document-focused. Get ready to turn your smartphone into a mobile office.
Preparation of the device and shooting conditions
Before you open the camera app, you need to be physically ready for the process. The quality of the final file depends on the lighting and stability of the hands. Find a place with bright but diffuse light. Direct sunlight or a flash from a ceiling lamp will create glare on the laminated page of the passport, which will make the text unreadable.
Wipe the camera lens with a soft cloth. Even microscopic fatty fingerprints can turn clear text into a blurred stain, which will automatically deny the document verification. Put the passport on a flat, dark surface, which will create the necessary contrast for automatic border detection algorithms.
⚠️ Warning: Never use a digital flash when scanning laminated pages.The flash creates white "hot spots" that completely hide the text and photo of the owner.
It is also important to check the resolution settings in the camera app itself, make sure you are not in macro shooting from close range if the lens is not allowing you to focus, the optimal distance is 20-30 centimeters from the document.
Use of the built-in Mi Scanner application
The MIUI shell and the new HyperOS already have a powerful document tool pre-installed, located in the Tools folder or searched through a menu, and this app automatically identifies the edges of a document, aligns it, and applies filters to improve readability.
Run Mi Scanner and point the camera to turn the passport around. The system recognizes the document and offers to take a picture. After that, you can choose the processing mode: "Document", "Photo" or "Passport". Document mode usually gives the best result for text pages, turning the background into pure white and the text black.
Once scanned, you have the option to immediately send a file or save it to a gallery. The app allows you to scan multi-page documents, combining them into one. PDF-File, which is extremely convenient for passports with visas or additional pages.
☑️ Scan quality check
Set up a standard camera for documents
If you prefer to use the standard Camera app, you will need to manually adjust the settings to achieve a professional result. Automode often tries to "improve" the face in the passport photo by blurring the text around. Switch to Pro or Pro mode if it is available on your Xiaomi model.
In manual mode, set a minimum ISO (usually 50 or 100) to avoid digital noise on the white background of the page. Focus (Focus) manually and adjust the letters to be as clear as possible. White balance (WB) is better set manually, focusing on the white color of the paper to remove yellowness or blueness.
| Parameter | Recommended value | Why do you need it? |
|---|---|---|
| ISO | 50-100 | Remove grain on a white background |
| Excerpt. | Auto or 1/60 | Prevents lubrication from hand trembling |
| Focus (AF) | Manual (MF) | It captures sharpness on the text without allowing the camera to “walk” |
| White balance | Manual (model) | Makes the background of the page pure white |
Use a timer in 2 or 3 seconds, and this allows you to press the trigger button and move your hand away so you don't shake your smartphone when you're shooting, and even microscopic movement can reduce the sharpness of small letters.
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Use a tripod or wrap your phone around a stack of books for absolute stillness while shooting with a timer.
Processing and improving image quality
Once a photo is taken, it often requires final processing. Xiaomi's built-in gallery editor offers powerful tools to do this. Open the photo, click "Change" and select filters. Document, Scan or B filters are the best fits.
These filters increase contrast by making black text deep and background white, and there's also a Magic or Improve feature that uses artificial intelligence algorithms to align the horizon and remove shadows. If the passport was photographed at an angle, the Cover tool allows you to align perspective manually.
⚠️ Warning: When processing in bl/b mode, check whether important watermarks or colored security elements are missing if they are required for inspection.
Save the final file in high quality JPEG format. Don't use memory saving compression in your camera settings if you plan to print a document or send it to government agencies where every pixel counts.
Third-party scanning applications
Built-in tools may not be enough for complex cases, such as if the passport is old, worn or has a complex background. In such cases, specialized applications from Google Play come to the rescue, with Adobe Scan, Microsoft Lens and CamScanner being the market leaders.
These applications have more advanced text recognition algorithms (OCRs) that can not only create a picture, but also recognize text, allowing you to copy the series and passport number to the clipboard, which eliminates errors when manually entering data.
Data security in third-party applications
Installing such an app on Xiaomi requires attention to permissions. Be sure to check what rights you give the program. Only access to the camera and storage is enough. Access to contacts or location for the document scanner is not necessary and should be prohibited.
Data retention and transmission formats
The file format you choose depends on where you send the scan. To download to public service portals or banking applications, JPG or PNG formats are most often required, which ensure good compatibility and acceptable file size.
If you send a passport by email or via a print messenger, you should use PDF format, which ensures that the document does not automatically shrink to low quality, as is often the case with pictures in messengers, and PDF can also combine the passport spread and residence into one file.
When sending via instant messengers (Telegram, WhatsApp, Viber), always choose the option "Send as a file" or "Document" rather than "Photograph", which will prevent automatic compression and loss of quality, which can make small letters unreadable.
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Always check the final file on another device (such as a computer) to make sure the text is clearly readable and there are no lights.