PHP，检测水印图像？ [英] PHP, detecting watermarked images?

问题描述

我有一个类似100万张图片的图书馆，其中大约有一半是在同一地点加上相同的，半透明水印的水印。

I have a library of like 1 million images, and roughly half of these are watermarked with the same, half transparent watermark in the same spot.

我在哪里开始，用水印检测图像？是否有一些标准工具用于此目的？

Where do I begin, detecting the images with the watermarks? Is there some standard tools for this purpose?

推荐答案

如果根据您的问题，您只想检测带水印的图像，您可以使用以下算法：

If according to your question, you just want to detect the images that are watermarked, you can use the following algorithm:

• 提取水印图像样本扫描水印图像


• 逐个像素地存储数组中的第一个像素。逐个像素地扫描每个


• 图像并存储在一个数组中。每当来自被扫描图像的行矩阵


• 包含


• 相同顺序的数组元素时，它很可能是匹配。

• Extract a sample of the watermarking image Scan the watermark image
• pixel by pixel and store the first pixels in an array. Scan each
• image pixel by pixel and store in an array. Whenever a row matrix
• from the image being scanned contains elements of the array in the
• same order, it's most likely a match.

代码可能是这样的：

$no_of_pixels = what_you_got;
$matched = 0;
$thumbpixels = array();
$wmark = imagecreatefrompng("watermark.png");
list($width, $height) =  getimagesize("watermark.png");
$tesimage = imagecreatefrompng("test.png");
for($h = 0; $h < $height; $h++){    
    for($w = 0; $w < $width; $w++){
        if(imagecolorsforindex($testimage, imagecolorat($testimage, $w, $h)) == $thumbpixels[0]){
            while($thumbpixels[$i++] === imagecolorsforindex($tesimage, imagecolorat($wmark, $w, $h)) && $no_of_pixels != $matched){
                $matched++;
            }
            if($matched == $no_of_pixels) echo "Voila, we found it!";
        }
    }
}

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编辑

只看到你的缩略图示例。如果您只想检测文字，可以尝试 tesseract-ocr 或 PhpOCR 。

您也可以考虑 PHPSane

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