Enlarging an image without losing quality is, of course, a big statement. When you increase the image size, even the smallest one, its quality is lost and additional pixels and artifacts appear.

Only images in vector format can boast the ability to scale up without losing quality.

As for increasing the size of images in JPG, TIF, BMP, GIF, PPM, PNG formats, instead of the concept “without loss of quality” we will use “with minimal loss of quality”. A small C++ / QT graphical application called “SmillaEnlarger” will help you lose at least the quality of the picture while increasing it.

The application is available in versions for Linux and Windows. Today we will look at its installation and use in the operating system.

HOW TO INSTALL SMILLAENLARGER. Open the Terminal, give the following commands to add a repository, update and install the application.

Sudo add-apt-repository ppa:dhor/myway sudo apt-get update sudo apt-get install smillaenlarger

After completing the installation process of the program, launch it.

HOW TO ENLARGE AN IMAGE WITHOUT LOSSING QUALITY

In the program interface, click on the “Open...” button, select the image we need and click on the “Open” button.

I uploaded an image measuring 320x213 pixels and using the “Zoom” slider I increased its scale by 1500%.

Click on the “Preview” button without changing the default settings and get the appearance of the final image. If everything suits you, click on the “Enlarge & Save” button, which will save the image, leaving the original one untouched in the same folder. If desired, we can try changing the filter settings.

Ultimately, we had an image measuring 320x213 pixels, but it became 4800x3195 pixels.

At the same time, the quality of the final image has become significantly better, with the same increase in scale.

This is not the only, but, in my opinion, the most correct answer to the question of how to enlarge an image without losing quality, dear blog readers! Please leave your feedback and comments, as well as ask questions.

04/12/16 59K

You don't know how to increase the size of a picture? This is a very simple task since everything you need is already installed on your computer. Read this tutorial and you'll learn how to resize a photo using 5 simple tools.

Method 1: How to Resize an Image in Microsoft Paint

1. Find and launch MS Paint. It comes pre-installed on all versions of the operating system Windows. Start> All Programs> Accessories> Paint:

1. Drag the image into the Paint window or use Menu > Open (Ctrl + O).
2. In the main menu of the program, find the item “ Resize" and select it:

1. The panel for changing image sizes and proportions will open. You can specify the value in pixels. Don't forget to check the " Maintain proportions" Otherwise the image will be deformed:

1. To increase the size of the picture, click the "OK" button and save the photo.

Adviсe:

• If you can't get your photo to the desired size without stretching it, you can use the Crop tool to remove unwanted edges. How to do this is described in paragraph 3;
• To open a photo faster, right-click on it and select “ Open with Paint»;
• It is best to save the image in the same format as the original.

Method 2. How to resize an image in MS Photo Gallery

1. If Microsoft Photo Gallery is not installed on your computer ( Start > Photo Gallery), you need to download and install it as part of Windows Essentials 2012;
2. Launch MS Photo Gallery and find your graphic file;
3. Right-click on it and select “Resize...”:

1. Select a ready-made preset: " Small 640 pixels", "Medium 1024", "Large 1280", etc.

1. Click " Resize and save" After you increase the size of the picture, the image will be placed in the same folder, and the original will also remain in it.

Adviсe:

• If you need to set the exact size of the image, select " Custom" and set the size to the larger side of the photo;
• To resize multiple photos at once, select them while holding down the Ctrl key.

Method 3: How to Resize an Image in Photoscape

You can increase the size of the picture in Photoshop. Or use Photoscape for this.

1. Download Photoscape and install it. Launch the program;
2. Go to the "Editor" tab and find the photo you want to edit:

1. At the bottom of the image there is a button " Resize", Click on it.
2. Set a new photo size. Make sure the option " Maintain aspect ratio" is enabled and press the "OK" button:

1. Save the edited image.

Adviсe:

• If you need to resize multiple images, use the " Batch editor" Add a folder and resize all the photos in it;
• If you don't know the exact size, you can set the "Percentage" of the original size.

Method 4. How to resize an image in IrfanView

1. Install IrfanView - a great tool for viewing and enlarging pictures;
2. Add a photo by dragging it into the program window, or by clicking the first button in the toolbar:

1. Go to the "Image" tab, select " Change size/proportions» ( Ctrl+R);
2. Set the new size in pixels, centimeters, inches, or as a percentage of the original image:

1. Save the image.

Adviсe:

• You can use standard sizes: 640 by 480 pixels, 800 by 600 pixels, 1024 by 768 pixels, etc.;
• To maintain high quality photos, make sure your DPI is set to at least 300.

Method 5. How to resize an image online

1. To resize a picture online, go to PicResize.
2. Click the button Browse" to select a photo. Click " Continue»:

1. Select a percentage of the original image, such as 50% smaller. The tool will display the output image size. Alternatively, you can enter your exact size by selecting " Custom Size»:

Using Photoshop, you can easily reduce or increase the size of an image. Moreover, this can be done in different ways depending on what result you are striving for.

Before we start looking at the methods, first a little theory.

Firstly, what is reducing or increasing the size of an image? First of all, this concept should be understood as reducing/increasing the resolution of a picture, that is, its length and width and, accordingly, the number of pixels that make up any raster image. .

Secondly, what happens to the quality of the picture after resizing it?

• During the reduction process, there is a loss of pixels, but the quality as a whole does not suffer, it remains quite clear.
• During the enlargement process, Photoshop stretches the pixels and draws them in accordance with its algorithm. Therefore, when enlarging, the picture quality always suffers. The higher the magnification, the more clearly the irreversible loss of quality is visible.

A similar issue was discussed in the lesson related to changing the layer size,

A clear example of how image quality changes:

In this article, we’ll look at 4 ways to change the size of a picture in Photoshop and look at when and which method is best to use.

Method 1 - Image Size Dialog Box

This is the classic and most universal way. It is suitable in most cases, especially when you already know to what size you should reduce and enlarge the image size.

Open the image in Photoshop.

Open dialog box Image - Image Size(or key combination - Alt+Ctrl+I). The following window will appear:

Pay attention to the fields immediately Width And Height. The values ​​that will be indicated there are the current dimensions of the image. By default they are measured in pixels.

If you initially know to what size you need to resize the image, then enter these values ​​in the above fields.

Proportions

If there is no checkmark in the window settings Maintain proportions, then you can enter any values ​​in the length and width fields. But you run the risk that the picture will be stretched vertically or horizontally. It is very easy to make a mistake and choose the wrong proportions.

Example without maintaining proportions

Example with maintaining proportions

Method 2 - Resizing using Transformation

Transforming an image is a cool method that definitely needs to be added to your Photoshop knowledge base. This method is good in two cases:

• reduce or increase the size of the entire image;
• Reduce or enlarge the inserted image in Photoshop.

Size details for each case.

How to reduce or increase the size of an entire image

Step 1

Open the picture. Select a team Editing - Free Transform or press the key combination Ctrl + T.

Note

If this command is not active (grayed out), then your background layer is locked to change. This is indicated by a padlock icon directly on the layer.

To unlock the background layer, double-click on it. A window will appear New Layer, Press OK.

Step 2

A frame will appear around the image. There are markers in the corners and on each side that you need to pull to make the image smaller or larger.

After resizing, click on the checkmark at the top of the options bar. There is a bug in Photoshop CS6 and this checkbox is not visible. If you also don’t see it, then press the Enter button to accept the changes or Esc to cancel.

Step 3.1 Case with magnification

If you enlarged the picture in this way, then, as you can see, part of it became hidden, it seemed to not fit into the size in which it was opened. On the one hand, this is also not bad and can also be used in some cases.

But if you insist on showing the entire image, select the command Image - Show all.

Step 3.2 Case when decreasing

When you zoom out, you'll see a checkerboard background. This is emptiness, transparency. It will disappear when you save the image. But it would be correct to cut off the void in order to ultimately see what the final size of the picture is.

To cut off the void, select the Image command - Trimming.

In order not to disturb the proportions of the image in this method, when you drag the frame markers, simultaneously hold down the key Shift.

How to reduce or enlarge an inserted image in Photoshop

In any case, take the case described above into account. Namely, the ability to use a command Free transformation(Ctrl+T). This technique will be needed to carry out such a common operation, as reducing or enlarging an inserted picture, item, object(call it what you want).

So, a familiar situation: you inserted another picture into your main image in Photoshop, but it did not fit in size.

Select this image and use the transform command. Now, as described above, pull the markers in the desired direction.

Method 3 - Canvas Size

Not the most popular method, but nevertheless we will also consider it - the command.

The peculiarity of this method is that we change the size of the image resolution, while the image itself does not change in any way. Photoshop simply cuts off part of the image (if we are talking about reduction), or adds a background color (if we are talking about enlargement).

That is, let's say your picture is 700x700 pixels. Through Image - Canvas Size you set the size to 500x500. As a result, Photoshop cuts off the extra 200 pixels in height and width. In the settings, you can specify where it cuts from: it is either evenly on all sides, or you can select a specific side.

How to reduce image size without losing quality

We looked at 4 ways to reduce image sizes. Of these, two methods: Canvas Size and Crop are not associated with loss of quality. In fact (width and height) the pictures become smaller, but the content itself remains the same size. To achieve this, you need to sacrifice part of the image, in other words, simply crop it to the desired size. For more details on how to do this, see the text above.

How to make a cropped image smaller in Photoshop

To reduce the size of a cut-out object in Photoshop, you need to be able to: cut out objects, manipulate the cut-out area (including reducing it).

Read about how to cut out objects in other articles. Let's look at reduction in more detail.

In this situation, you will also need to know how to use the command Free transformation.

When the object is cut out, you need to form a shape around it. After that, apply a transformation and, according to the instructions above, drag the handles in the direction to make this object smaller.

In any case, when reducing the cut fragment in the free space, Photoshop will automatically add a background color. Therefore, if you have a simple case, then take care first and select the same background color that surrounds the object to be reduced. To do this, get a color sample using and .

If you notice an error in the text, select it and press Ctrl + Enter. Thank you!

To understand what processes are involved in the mechanism for resizing an image, read the building material of any raster image. In short, these are small colored squares that, like a mosaic, make up a picture.

When we talk about sizes, we talk about permission. It is written as the sum of pixels in one row in width and one column in height and is written like this: 655x382. These are the dimensions of the following art:

Therefore, when resizing the image, we must change the values ​​of these pixels in width and/or height.

In case of size reduction, for example, let's change our example to 300x175, the image will already consist of 300 pixels in width and 175 pixels in height. No narrowing occurred. Photoshop recalculated the pixels in the image and figured out which ones it could get rid of.

But this process is not reversible. If you need to return everything back or do even more, then a new process will start - increase.

In case of increasing size, Photoshop calculates which pixels are missing and adds them based on complex processing algorithms. This process cannot be of high quality, so when the image is enlarged, the quality is lost. The picture loses the clarity of details and becomes blurry. For clarity, I will enlarge the example above to its original size. Compare:

Thus, when enlarging, the quality will greatly depend on the initial size of the image and on the course to which you need to “grow”.

Image Size Dialog Box

So, the most basic way to resize an image is to use the menu command:

Image - Image Size.

Hotkey: Alt+Ctrl+I.

A dialog box will open:

This dialog box allows you, firstly, to obtain information about the current image dimensions, and secondly, to actually change them.

Pixel Dimensions

To change the image size change the values Width and Height. By default they are measured in pixels, but you can select percentages from the drop-down list.

Notice the bracket and chain icon. This means that when you change the width or height, the second value will automatically change in the same proportions as the original image. This is necessary so that it does not turn out compressed or elongated. To enable/disable this function, check the box. "Keep proportions"(Constrain Proportions).

Document Size

I mentioned this group of settings when talking about the printer. Permission(Resolution) changes the pixel size and affects print quality. For printers, feel free to set it in the range of 200-300 pixels per inch.

The Width and Height values ​​tell us what sizes of paper the image can be printed on. Changing the numbers will change the size of the image. Please note that there is also a function for maintaining proportions.

Scale Styles

Determines whether the program will scale any layer styles applied to the image. It is recommended to leave this option checked, otherwise, for example, the shadow you add may end up being larger or smaller than the picture itself.

Interpolation

This is your key to changing resolution without affecting image quality. Interpolation Resample Image is the process by which Photoshop responds to a resizing command by adding or subtracting pixels. The problem is that when interpolating, the program “makes assumptions”, and this can ruin the quality of the image.

When you first start the program, setup Interpolation is turned on, and is responsible for increasing or decreasing the number of pixels in the image. These processes reduce image quality as the program either creates pixels or chooses which ones to remove accordingly. By disabling the setting, you protect quality by locking the pixel size.

When you check the box Interpolation, you need to select a method from the drop-down list below. Why might this be needed? Sometimes you'll need Photoshop's help to create an image larger or smaller than the original.

For example, if you have an image with the resolution 200 pixels per inch, the size of which when printed is 4x6, and the size of the printed version should be 5x7 and it is advisable to keep the resolution at 200 pixels per inch. To do this, you can check this box.

The drop-down options below the Interpolation check box determine what form of math Photoshop uses to add or remove pixels. Since higher image quality means more work, the better the image, the more time it takes for the program to complete the above process.

Here are your options, sorted by quality (worst to best) and speed (fastest to slowest):

• By neighboring pixels (preserves sharp edges) (Nearest Neighbor). Although this method results in the lowest image quality, it can be useful because it produces the smallest files. This is useful if you are transferring files over the Internet and you or the recipient has a slow connection. This method works by looking at the colors of surrounding pixels and copying them. It is known for creating jagged edges, so you should only apply it to images with hard edges, such as illustrations, that have not been smoothed.
• Bilinear. If you choose this method, Photoshop will guess the color of the new pixels, choosing a middle ground between the color of the pixels immediately above and below, and to the left and right of the one being added. The result of this method is slightly better than when choosing the option By neighboring pixels and it's still pretty fast, but you're better off using one of the following three methods instead of Bilinear.
• Bicubic (best for smooth gradients). This method determines the colors of new pixels by averaging the colors of the pixels directly above and below the new one, as well as the two pixels to the left and right of it. This method takes longer than the previous two, but creates a smoother transition in areas where one color is replaced by another.
• Bicubic Smoother (best for enlargement). Close to the previous method in the way new pixels are created. Using this method, the pixels are slightly blurred so that new ones can be superimposed on old ones, giving the image a smoother, more natural look. It is recommended to use this method to enlarge images.
• Bicubic Sharper (best for reduction). This method is also similar to the method Bicubic (best for smooth gradients) in the way it creates new pixels, but instead of blurring entire pixels to improve the blending of new and old like the previous method, it only softens the edges of the pixels. It is recommended to use this method to reduce images.

With the advent of photography in the first half of the 19th century, a natural desire to enlarge the image to the size of an artistic canvas could not help but arise. One of the real and most effective methods, which is still used to this day, was to redraw it cell by cell, but today such advice is rarely given, because it is obvious that those who want to enlarge an image are interested in how to increase the size of photographs on a computer.

Image size on PC monitor

Since we're talking about a PC, let's say that on the monitor the size of images is reduced/increased using the Ctrl (-/+) key combination or the mouse wheel with the same Ctrl key pressed. And if you're online, you can influence the size of the image by changing the scale in the "View" tab in the browser menu. No one is forbidden to resolve), calling this command by right-clicking directly on the desktop.

Now, if you follow the principle “from simple to complex,” you need to figure out how to increase the size of photos in Paint, because, firstly, it is a standard graphics editor (Start > All Programs > Accessories) that comes with the Windows operating system, and secondly, many are not aware of some of its abilities, including the “Resize” button on the “Home” tab.

Stretch the picture in Paint

In the "Resize and Skew" dialog box, you usually check the "Maintain proportions" checkbox and specify either a percentage or a specific value in pixels. In the second case, it is enough to specify only the desired image width (change horizontally) for the second parameter to change automatically.

Some versions of Paint also have a "Points" option that allows you to enter specific dimensions for the image. If everything is OK, tell the editor so.

When figuring out how to enlarge, most users probably don’t even consider it necessary to add that without loss of quality, believing that this goes without saying. However, this tacit condition is not so easy to satisfy, because the image can be roughly compared to a mosaic of multi-colored pixels. It is not difficult to imagine what the picture will look like if it is simply stretched, because the number of informative pixels will remain the same, but the physical size will increase.

In order to somehow maintain quality to a certain extent, you need to fill the “voids” taking into account the content of the surrounding pixels. Unfortunately, good old Paint is far from the best at this, but there are many programs that, using various algorithms for interpolating data between stretched pixels (resample methods), can enlarge images with very decent quality. Most of these services, among which the paid PhotoZoom Pro is especially popular, are functionally similar and easy to use, but simply recommending them to those who want to learn how to increase the size of photos in Photoshop would be an evasive answer.

Photoshop's ability to resize photos

If you are going to enlarge an image, you must keep in mind that the result directly depends on the quality and size of the source material. After loading the photo into Photoshop, select the “Image Size” command in the “Image” menu, thereby opening a window of the same name, in which you conduct a dialogue with the program.

If you completely trust the program, you can only specify the width and height in the fields of the "Document Size" block, and leave the remaining parameters selected by default, including the "Interpolation" function (Resample Image) and the "Bicubic Automatic" resampling method (Bicubic), which is generally preferred over the other five algorithms. Then use the “Auto…” button to open the “Automatic resolution selection” window, select the desired quality (the default is “Good”) and click OK.

Note: Resampling is a function that controls the amount of data in images that are resized or resized.

Little tricks

Perhaps not everyone knows about some well-known recommendations on how to increase the size of photographs with minimal loss of quality using any graphic editor with correction and resampling functions, but it does not have to be Photoshop.

First, you need to prepare the original image by slightly enlarging it and carefully examining it for noise, blurry areas (where they should not be), various spots and other possible defects. All shortcomings must be eliminated (corrected) and only then proceed to resizing.

Next, you need to enlarge the photo twice as large as planned, work with sharpness, contrast, saturation, then return to the desired size and make sure that the quality remains at the proper level. Here's a little trick, but that's not all.

What people will come up with in search of an original solution to how to increase the size of photos.

It turns out that if you enlarge the image size by 10%, there will be no visual deterioration in quality. This suggests an obvious conclusion: by repeatedly increasing the size by 10%, you can... well, then - who has any imagination. But this method is not universal, and its indiscriminate use for all photographs in a row will not necessarily lead to good results, which largely depend on various quality parameters of the image, including the format. For example, they manage to stretch a black and white photograph up to 50%.

These “secret” techniques are permissible only in cases where for some reason there are no other options, and, most likely, the “cunning production” will require very serious post-processing in Photoshop.

Specialized programs

If you need an answer to the question of how to increase the size of photos with minimal headaches, use one of the specialized programs that have more interpolation algorithms than Photoshop and their own original technologies. In addition to the previously mentioned PhotoZoom Pro program, these services are: Perfect Resiz, Reshade Image Enlarger, OnOne Genuine Fractals Pro v6.0, Akvis Magnifier v3.0 and others.