


How to implement the function of randomly generating watermark images in PHP
This article mainly introduces the relevant information of PHP to generate random watermark images in detail. It has certain reference value. Interested friends can refer to
GD graphics library based on PHP. Generate an image. Only for those who are new to the GD library and can learn from examples.
1. Requirements
The layout of the website uses a style similar to the MOOC course list. Each course is a banner picture, and below the picture is the title and introduction. Because there are a large number of courses, there are no special banners designed for all courses, so you need to generate images yourself according to certain rules (I originally planned to use p layout to solve the problem, but p img is not well controlled in responsive layout).
Generated renderings:
2. Tools & Materials
1. Open PHP GD graphics library extension
2. Prepare multiple small watermark images
3. Get the background color RGB value of the pre-generated image
3. Code
The process of generating images is detailed in the code.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 |
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So we can use it directly in the page to display the image directly.
Note: I encountered a problem during the process: if the watermark image is a transparent png image, when you copy the watermark image to image, it will appear as The white background cannot be transparently blended with the image background we set, so the same color processing needs to be done for random watermark images.
4. Summary
This small example uses simple steps to generate an image, which can be displayed directly in the browser, or it can be given to imagepng Add the second parameter, which is the path, to save the image. Therefore, by learning several methods in the GD library in the examples, you can create pictures, add text watermarks, or image watermarks to pictures.
The above is the entire content of this article, I hope it will be helpful to everyone's study.
Related recommendations:
PHP implementationPicture watermark class encapsulation
PHP implementationPicture watermark class encapsulation code sharing
The above is the detailed content of How to implement the function of randomly generating watermark images in PHP. For more information, please follow other related articles on the PHP Chinese website!

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