How can I merge the positive and negative images into o…

One option to merge front and back images into one image is to use the GD library in PHP. Here is a simple example code:

// 创建一个空白图片
$combinedImage = imagecreatetruecolor(200, 100);

// 加载正面图片
$frontImage = imagecreatefromjpeg('front.jpg');

// 加载反面图片
$backImage = imagecreatefromjpeg('back.jpg');

// 将正面图片复制到合并图片上
imagecopy($combinedImage, $frontImage, 0, 0, 0, 0, 100, 100);

// 将反面图片复制到合并图片上
imagecopy($combinedImage, $backImage, 100, 0, 0, 0, 100, 100);

// 保存合并图片
imagejpeg($combinedImage, 'combined.jpg');

// 释放内存
imagedestroy($combinedImage);
imagedestroy($frontImage);
imagedestroy($backImage);

In the code example above, we first create a blank merged image. Next, we load the front and back images using the imagecreatefromjpeg function. Then, we use the imagecopy function to copy the front and back images onto the specified positions of the merged image. Finally, we save the merged image using the imagejpeg function and free up memory using the imagedestroy function.