Complete Tutorial on AI Image Processing, 2026 6 Practical Tips for Cutting Out Pictures, Modifying Pictures, Changing Pictures and Changing Backgrounds

Complete Tutorial on AI Image Processing, 2026 6 Practical Tips for Cutting Out Pictures, Modifying Pictures, Changing Pictures and Changing Backgrounds

In the past, when processing a picture, you had to rely on manual strokes to cut out the picture, adjust parameters repeatedly in professional software, and change the background often took half a day. Nowadays, AI image processing tools compress these tedious steps into a few clicks. Ordinary people do not need to understand professional concepts such as layers, masks, and channels to create clean and neat finished products. This tutorial does not use jargon, but directly explains what AI image processing can do for you, as well as how to operate the six most commonly used techniques of cutting out images, retouching images, expanding images, changing backgrounds, partially redrawing, and improving clarity. Whether you want to change the background of e-commerce products to a clean one, or want to clean up old photos, you can find the corresponding method here. After reading this, you can probably understand why more and more people leave image processing to AI.

What exactly can AI image processing do?

Simply put, AI image processing is to let the algorithm complete the work for you that originally required manual pixel-by-pixel operations. Its core capabilities can be divided into two categories: one is to transform existing pictures, such as cutting out the subject, removing passers-by, clearing up blurry faces, and adding a larger area to the picture; the other is to understand the content of the picture and then perform semantic-level editing. For example, if you select an area and say "Change this dress to red," it can redraw it while keeping the light and shadow consistent. The biggest difference from traditional software is that AI can understand what is in the picture, so it knows where the people are, where the sky is, and where the ground is. The operation is more like communicating with a knowledgeable assistant rather than mechanically dragging control points. Once you understand this underlying logic, you will be able to learn the following six techniques smoothly, because they are essentially calling on different combinations of AI's two abilities of "understanding the picture" and "redrawing".

Tip 1: Cut out pictures with one click, say goodbye to manual strokes

Cutting out images is the most frequent requirement and is also the earliest mature capability of AI. The traditional method is to outline the edges of the main body bit by bit, and it is almost impossible to clean the edges of hair and plush. The logic of AI cutout is completely different. It first identifies the subject in the picture, and then automatically calculates the boundary between the subject and the background. Even hair strands and translucent areas can be separated relatively naturally. In terms of operation, you usually only need to upload an image, click "cut out" or "remove background", and you can get a transparent PNG in a few seconds. It has a wide range of daily uses: e-commerce stores use it to turn products into white backgrounds, separate characters when making posters, and organize ID photos to change the background color. It should be noted that if the main body of the original image is too close to the background color, or the edges are too cluttered, AI may also leave burrs. At this time, most tools provide manual smear remedial brushes, which can correct the areas that need to be retained or removed. For most scenarios, the finished product of one-click cutout is enough to be used directly.

Tip 2: Intelligent photo editing to remove defects

Editing pictures used to be the most troublesome thing, because removing a debris meant manually sampling from the side and then covering it up bit by bit. If the cover was not covered well, obvious traces would be left. AI retouching turns this step into "select and disappear": you circle the extra wires in the picture, the garbage on the ground, and the passers-by who intruded in the photo, and AI will automatically complete the area based on the surrounding texture and structure, making it look like there is nothing there in the first place. The same goes for portrait retouching. Acne removal, wrinkle reduction, and skin resurfacing can all be accomplished while retaining the texture of the skin without turning it into a plasticky mess. Such functions are usually called "eliminate", "remove passers-by", "one-click beautification" and the like in tools. Here is a tip for actual use: the smaller the object to be eliminated and the more regular the surrounding background, the more natural the completion effect will be; if you want to remove an object that occupies a large area of ​​the screen and is covered by a complex background, you may need to process it several times, in small pieces, and the effect will be much better than framing a large area at once.

Tip 3: Expand the picture to make the picture larger

Image enlargement solves the problem of "too crowded composition" or "insufficient size". For example, if you take a photo with a vertical composition and now want to post it as a horizontal cover, if you crop it directly, the content will be lost, and if you stretch it directly, it will be deformed. AI image enlargement can add reasonable extension content out of thin air around the original image: continue to draw the background on both sides of the character, complete the truncated desktop, and connect a section of the sky upward. It is based on the existing color, light and perspective relationships of the original image, so the supplemented part can usually be integrated with the original image. This ability is particularly useful for matching images for different platforms. A piece of material can be expanded into square images, horizontal images, and vertical images to suit public accounts, video covers, and posters respectively. When using it, it is recommended not to expand too much at one time. The larger the range, the more content the AI ​​needs to "imagine", and the higher the probability of errors or strange repeated textures. Gradually expand outwards in two or three times, and confirm each time before continuing. The result will be much more stable, and it will be easier to maintain a consistent atmosphere with the original picture.

Tip 4: Change the background and switch scenes at will

Changing the background is a natural extension of the ability to cut out images. First, accurately cut out the subject, and then match it with a new background. The portrait can be instantly moved from a messy living room to a solid-color studio, a cafe, or an outdoor lawn. The advanced aspect of AI background changing is that it is not just a simple texture. A good tool will automatically adjust the light, shadow and color temperature of the subject's edge, making the character and the new background look like they were taken in the same environment, rather than being cut and pasted together. This trick is almost standard in the e-commerce scene. The same piece of clothing can be replaced with different styles of backgrounds to create a series of pictures; individual users often use it to make interesting combinations of travel check-ins, or to change the background of ID photos into the prescribed red, blue and white. If what you want is not a ready-made background, but needs to generate a brand new creative background or material picture from scratch, then it belongs to another type of tool. We will specifically mention this when we talk about tool selection below, because cutout and original generation follow two different technical paths.

Tip 5: Partial redrawing and precise modification of details

Partial redraw is currently the most "magical" function, which allows you to modify a certain part of the image just like giving a command. The specific method is to use a paintbrush to paint the area you want to change, and then describe the result you want in one sentence, such as "change short sleeves to long sleeves", "add a window to this wall", "change daytime to dusk". AI will only regenerate the area you selected, leaving the rest intact, and try to make the new painting content naturally connect with the surroundings in terms of style, light and shadow, and perspective. This ability changes picture editing from "adjusting parameters" to "communicating with language", and the threshold is suddenly lowered to the point where ordinary people can get started. It is suitable for fine local adjustments: changing clothes, changing hairstyles, adjusting the color and style of products, trimming and adding certain elements. The more specific the prompt words are written, the closer the results will be to expectations; if you are not satisfied at one time, it is also a normal operation to draw the best one several times, because each generation will be slightly different.

Tip 6: Improve clarity and turn blur into high definition

Old photos are blurry, screenshots are distorted, and they are all mosaic after enlargement. These can all be saved by AI's sharpness enhancement. Its principle is to "guess" the original details based on the picture content and fill them in, rather than simply sharpening the edges, so the picture can still remain relatively clean after being enlarged several times. Common uses include restoring facial features from blurry old photos, losslessly enlarging small images for printing, and upgrading low-definition materials found on the Internet to usable resolutions. What needs to be explained objectively is that AI enhancement adds reasonable inferred details rather than real information, so you must have psychological expectations for face restoration: it can make the photo clearer and more beautiful, but the details added may not be completely consistent with the person. It is not suitable for scenes involving documents and evidence collection that require high authenticity. For daily sharing, nostalgic restoration, and material amplification, its performance is usually quite capable.

What dimensions should you consider when choosing tools?

There are many AI image processing tools on the market. When choosing, don’t just look at the promotional words, focus on several practical dimensions. The first is whether the functions are complete. It is best to close the loop of the first six skills in one tool, otherwise it will be a hassle to flip back and forth between multiple software. The second is the processing quality, especially the naturalness of the edges of the cutout and partial redrawing. The same picture may be very different in different tools. It is recommended to try it with your own real material before making a decision. The third is the output limit, free quota, whether there is a watermark, and whether it can export high-resolution original images. These directly affect the actual usability. The specific rules are different from each company. Just read the current instructions clearly before using it. The fourth is the ease of operation and Chinese support. Whether the interface is intuitive and whether prompt words can be in Chinese will have obvious differences in the domestic user experience. Finally, we need to consider how the data is processed, how the uploaded images are stored, and whether they will be used for other purposes. This is especially noteworthy when it comes to portraits and privacy. By comprehensively weighing these items, you can basically filter out most of the flashy choices.

How to choose between mobile phone and computer solutions

Whether to use a mobile phone or a computer depends on your usage scenario and accuracy requirements. The advantage of the mobile phone is that it can be taken and modified at will. It is suitable for lightweight needs such as social sharing, travel check-in, and temporarily changing the background of pictures. Most apps make it easy to cut out pictures, eliminate them, and beautify them with one click, which is especially convenient when going out. The computer side is better because of its large screen and precise operation. When doing partial redrawing, you need to reselect the area repeatedly, expand the image and carefully compare the seams. When processing dozens of e-commerce images in batches, the efficiency of enlarging the screen with the mouse is much higher than poking on the small screen. A more worry-free idea is to combine the two ends: you can use your mobile phone to solve minor repairs, and return to the computer when you need to elaborate or batch drawings. It is worth mentioning that if your need is not to change pictures but to generate illustrations, creative materials or brand-new pictures from scratch, then there are now quite mature options on mobile phones. for exampleLingtu(App Store's full name is Lingtu-AI Drawing Design) is an iOS application that is biased toward original creation. You can download it by searching for "Lingtu" in the iOS country without using a VPN. It brings together engines of different styles. The Midjourney style is more atmospheric, the Flux style is more realistic, and the Nano Banana style focuses on quick picture production. It also supports Chinese interaction and localized prompt words. When you want to directly generate a new material picture, it is more suitable than a pure picture modification tool. This type of original generation and the cutout and retouching mentioned above are two different paths, which can be used together as needed.

Common pitfalls and copyright issues

Using AI to process images saves worry, but there are a few pitfalls worth knowing in advance. On a technical level, AI will occasionally "make its own decisions", such as filling in extra limbs when enlarging the image, changing areas you did not select when redrawing parts of the image, or changing the face to look less like you by enhancing the definition. When this happens, don't forcefully adjust it. It is often faster to redo it from another angle or narrow the processing range. Vague descriptions of prompt words are also a common problem. The more specific they are, the less likely they are to overturn. What needs more attention is copyright and compliance. If you use AI to modify pictures taken by others or copyrighted by others, you must confirm that you have authorization before commercial use. You cannot use it just because "AI has modified it" by default. When it comes to portraits, whether it is changing the background or partially redrawing, using other people's faces for commercial promotions also requires personal consent. Unauthorized synthesis and grafting may bring legal risks. Each tool has different copyright ownership and commercial licensing regulations for generated content, and they are often adjusted according to public information. It is best to check the current specific terms of the tool you are using before official commercial use. Only by thinking clearly about these boundaries can you enjoy efficiency without setting yourself up for trouble.

FAQ

Can AI cutout handle complex edges like hair?

Yes, this is the biggest advantage of AI cutout compared to manual strokes. It calculates the boundaries by identifying the subject, and the processing of complex edges such as hair and plush is usually more natural. If the main body of the original image and the background color are too close, resulting in burrs on the edges, most tools also provide manual smear brushes for secondary correction.

Are the details of old photos restored using AI to improve clarity real?

Not exactly. AI enhancement is to infer and fill in reasonable details based on the content of the picture, rather than restoring the real information, so the restored face may not be exactly the same as the person. It is suitable for daily nostalgia, sharing, and material amplification, but it is not recommended for scenarios involving documents, evidence collection, etc. that require high authenticity.

Are cutting out pictures and changing the background and AI-generated pictures the same thing?

no. Cutting out pictures and changing backgrounds is a transformation based on existing pictures, which is an editing ability; while generating new pictures or creative materials from scratch follows the technical path of original generation. If you need to directly generate new materials, you can consider an original generation tool such as Lingtu. It aggregates a variety of style engines and supports Chinese interaction. It has a different positioning than a pure image modification tool.

Is there any difference in the effect of processing pictures on mobile phones and computers?

The effect itself is not much different, the difference is mainly in the operating experience. Mobile phones are suitable for the lightweight needs of shooting and modifying at will; the computer screen is large and the operation is precise. Partial redrawing and image expansion are more efficient than joint or batch processing. A common practice is to use a mobile phone for minor repairs, and use a computer for detailed work and batch drawings.

Can images processed with AI be used commercially?

It cannot be used casually by default. If the original image was taken by someone else or is copyrighted, you must confirm authorization before commercial use; the synthesis involving other people's portraits also requires your consent. Each tool has different copyright and commercial license regulations for generated content and may be adjusted. According to public information, it is best to check the current specific terms of the tool you are using before formal commercial use.