Each of us uses the Internet every day and deals with images in a variety of formats, most of which were created not to hold complete picture information, but to hold as much of it as possible while taking up as little space as possible.
Not only that, but the images we see are often the result of being 'created' and then forwarded and shared through complex channels on the Internet, with too many opportunities for compression (chat software, browser traffic-saving access, forwarding by various applications, etc.). The 'mosaic' we see may have originally been a high-definition, gorgeous image of.
The greening effect does indeed pull off the effect after 27 simulated retweets, image credit: Github/LionNatsu/ terribleGreen.
When we like a particular image and want to use it as wallpaper or PPT material, we find that the clarity of the image that looked fine turns into a "mosaic". If we really like the image, we will go to the trouble of finding the original image, but assuming that the image is not as sharp as we want it to be when they are uploaded, then even finding the original image will not help. In addition to finding the original image, we can also try to use some online services and websites to enlarge the image to even sharper than the original, today I will take you through a few famous image enlargement websites and software and compare their pros and cons.
Statement before the introduction: it is theoretically impossible to truly zoom in on an image losslessly. Image enlargement cannot "create" information that was not there originally, lost (shaky hands, mosaic, super high noise), all the image enlargement algorithm does is "guess" what was there originally, and a good algorithm guesses more accurately, so it is better to enlarge images that originally had details, but were just compressed by the image algorithm.
- Test photo by Wozzy Kippard
- Test illustration by apapico/
Illustrations, comics, secondary and non-realistic images
Waifu2x: Twice the size of a paperweight 'wife'
Waifu2x, which translates to "double the size of your paper wife", is a nerdy name for a picture algorithm that is sweeping the field of artificial intelligence (machine learning).
One of the advantages of machine learning is that after giving a specific input and output, it is able to find the connection between the input and output on its own, after which you then give it the relevant input to automatically generate the output. Seeing this should give you an idea of what a geek who knows machine learning can make, right? That's right, he used a bunch of low- and high-resolution Galgame images to train a deep convolutional neural network so that the algorithm learned to turn low-resolution Galgames into high-resolution Galgames.
That's how Waifu2x came to be. As an AI algorithm trained with Galgame, its best feature is its ability to achieve near 'lossless' perfect enlargement of illustrations, manga, secondary and other non-realistic images.
We can use Waifu2x's demo site to zoom in on our own image, which actually looks like this (right-click and select "View image in new tab" to see the original image more obviously).
Illustration 100% zoom demo, original + noise reduction low medium high 
Photo 100% zoom demo, original + noise reduction low, medium and high As you can see, Waifu2x holds up very well at twice the zoom level. The color is even more pure than the original image, so it can be said to have achieved a clarity "beyond the original image". However, the enlargement effect of real photos is not so amazing, and can only be said to be at the same level as other image enlargement algorithms.
Since it is only for demonstration purposes, the site only supports zooming in on images with a maximum resolution of 1500*1500, and also requires a certain network environment (Google Captcha is used).
#### Bigjpg: domestic version Waifu2x
Bigjpg is another online image enlargement site that uses the Waifu2x algorithm, supporting resolutions up to 3000*3000 (under 10MB), while providing stress-free domestic access. Since it uses the same algorithm, I won't repeat it here. Bigjpg also offers a paid service, which allows you to pay for the privilege of larger magnification, simultaneous enlargement of multiple images and independent server processing.
Bigjpg also has an Android app with WeChat applets, which I personally find more convenient and useful than the website, and recommend you Use its WeChat applet.
## Waifu2x-caffe: Waifu2x with graphics hardware acceleration
While online Waifu2x enlargement is convenient, it has several disadvantages for people who have the need to frequently enlarge images and enlarge multiple images (e.g. Gifs, videos).
- There is a limit to the size and resolution of the image, you can't convert 2K to 4K or 4K to 8K.
- The speed is too slow. This is the main reason, not only are large images slow to upload, but the lack of performance of the servers used by the niche services causes them to be processed very slowly, taking from a few tens of seconds to ten minutes a picture on average for me just can't wait.
- It crashes when processing a lot of images at the same time, and it can be maddening to wait a few minutes only to be prompted with a failed zoom.
- The algorithm and magnification are not customizable, Waifu2x itself supports unlimited magnification (provided the performance is sufficient), but online you can only magnify twice (Bigjpg's 16x magnification requires payment) and the settings are not detailed enough.
This is when we need to always have Waifu2x-caffe - the native version of Waifu2x - on our computers to zoom in on the images.
The usage is simple, download back from Github -> open the app -> drag in the image to be processed. There is no resolution and size limit, no magnification limit (magnification is directly the number input box), detailed settings support (image conversion format, model for image magnification reference, etc.).
Most importantly, it supports CUDA hardware acceleration for Nvidia graphics cards, which means one word - fast. - FAST. On the latest 10-series Nvidia graphics cards it processes even faster than it takes time, and many subtitlers and webmasters use it to double the clarity of videos and animations.
Emoticons, icons & other simple pictures
vector image with infinite zoom
In addition to AI and other image enlargement algorithms, there is a way to infinitely improve image clarity -- and once and for all -- by converting images to vector images.
What is a vector image? As we all know, general bitmap images save pixel information, for example, a 200*200 resolution image saves information of 40,000 pixel points; while vector images save information on the location of key points, and the shape, outline, size and other attributes of the graphics formed by connecting these points.
One advantage of vector graphics is that there is no such concept as resolution. By mathematically calculating the points and graphical information it holds, it renders the picture as we can see it, so vector images are not distorted by zooming in as many times as possible.
If vector graphics are so great, why don't we make all our pictures vector graphics? Take a modern smartphone for example, the amount of information to be saved in a photo taken to break it down into points and shapes is huge, and calculating that many points and shapes when viewing it requires super high performance. So the vector image enlargement service below is better suited for simple images like emojis, icons and the like.
Consequences of forcibly converting HD pixel images### Vector Magic
Vector Magic can fully automate the conversion of any uploaded image to vector, and I have prepared three images of varying complexity so that you can visualize which images get the best results when converted to vector.
As you can see, the less the color gradient and the more distinct the border, the better the result. Emoticons are this type of image, and after conversion we can save them as SVG. To use them, convert online to PNG at any resolution you want.
However, the biggest disadvantage of Vector Magic is that there is a charge for saving, or a monthly charge, and we recommend using the following free website (to visually show the effect put into the first introduction. (As for the cost, you can check it out for yourself if you're curious, I was shocked anyway).
Image Vectorizer
Image Vectorizer can also fully automatically convert any uploaded image to a vector image, and it.
- Completely free and able to save multiple formats.
- Being able to see the conversion has a technological feel to it.
- Support AI auto-adjustment to optimize the conversion effect.
- Provides professional color depth and toning settings so that professionals can get better conversion results.
From the results, Image Vectorizer's auto mode is much better than Vector Magic's (so Where did you get the courage to charge so much for Vector Magic?)
In addition to image enlargement, sometimes the use of photo vectorization can produce nice artistic effects.
Photo and bitmap images
The next step is finally to the most common photo enlargement. Unlike the above types of online services, the photo enlargement recommendations are all software. Again, all photo enlargement software cannot restore information that does not exist (those who want software to restore license plate numbers from a few pixels can give up).
A Sharper Scaling
A Sharper Scaling is a super lightweight image enlargement software that requires the Microsoft .NET 3.5 framework. Once installed there are only a few simple buttons, and as per usual tried the following enlargements of photos and illustrations.
Note: The comparison image provided by the software is not a comparison of the original image and the enlarged image, but a comparison of the traditional image enlargement algorithm and A Sharper Scaling algorithm zoomed image comparison, you need to pay attention when using it (a bit anti-human design, I used most of the time before I noticed ......) .
A Sharper Scaling does a good job of enlarging photos, at least much better than the traditional enlargement algorithm next to it. However, contrary to Waifu2x, non-realistic images such as illustrations can't be enlarged with it, the effect is very insignificant and sometimes even counter-productive.
Photozoom Pro
Photozoom Pro is a veteran image enlargement software that has been consistently updated for 13 years and is used by many companies in the professional field, the latest version is Photozoom Pro7.
As a professional software, it is naturally very good for photo enlargement, with many built-in image enlargement algorithms, we can manually adjust the best algorithm according to the photo We can manually adjust the best algorithm depending on the type of photo. After adjusting, you can directly input or drag the slider bar to the desired resolution, and the enlarged effect will be displayed on the right side in real time.
Each algorithm inside Photozoom Pro has more detailed settings, allowing users to slowly adjust it for different images until they achieve the the best enlargement effect. Again, it's not particularly effective for enlarging non-realistic images such as illustrations, but it's much better than A Sharper Scaling, and requires some patience to achieve some results.
Photoshop comes with adjustments
Finally, I'll give you a brief explanation of how to zoom in on an image inside PS.
- Open the image you want to enlarge in PhotoShop.
- Click Image -> Image Size, shortcut Alt + Ctrl + I to open the image resize window.
- Enter the new resolution you want, and under 'Resample' below you can choose from several simple algorithms.
- Click OK.
With today's recommended websites and software, you will be able to create PPTs or set wallpapers, and encounter all types of images in "low definition to high definition and high definition to Blu-ray". HD to Blu-ray" now. If you like this article, please click the red heart or follow me, see you in the next article.