OCR technology and its application in PHP

With the popularization of the Internet, the production and application of various digital materials are becoming more and more widespread, of which pictures are only one of them. In some scenarios, the information contained in the picture needs to be recognized and converted into numbers that can be read by a computer. In this case, the support of OCR technology is needed. This article will introduce the application of OCR technology in PHP and related knowledge.

OCR (Optical Character Recognition, optical character recognition) is a pattern recognition technology. Its basic idea is to convert the characters and text appearing in the image into information that can be processed by the computer. In the past, the application scope of OCR technology was limited to printed text, but with the continuous development of technology, its application has gradually extended to handwriting, printing, semi-manual and semi-printing, industry special symbols, etc.

In PHP, we can use Tesseract OCR to perform OCR related operations. Tesseract OCR is an open source OCR engine developed by Google and supports multiple languages ​​including Chinese. It relies on the Leptonica image processing library and can read images in TIF, JPEG, GIF, PNG and other formats and convert them into text in UTF-8 format. Using Tesseract OCR can realize automated image text recognition and processing, which can be applied in many fields, such as automatically identifying license plate numbers, detecting verification codes, etc.

When using Tesseract OCR for OCR operation, we can first convert the image to be recognized into a black and white image (binary processing), and then use Tesseract OCR for text recognition. The following is a simple PHP example:

<?php
$target_file = "image.jpg"; //待处理的图片文件路径
$im = new imagick($target_file);
$im->setImageColorspace(255);
$im->setCompression(Imagick::COMPRESSION_NO);
$im->setCompressionQuality(0);
$im->setImageFormat("tiff");
$im->writeImage("temp.tiff");

$command = 'tesseract temp.tiff output -l chi_sim'; //执行OCR命令
exec($command);

$file = fopen("output.txt", "r"); //读取转换后的文字
echo fread($file, filesize("output.txt"));
fclose($file);
?>

In the above example, we first use the ImageMagick library to convert the image to be processed into a black and white image and into tiff format (a format supported by Tesseract OCR), and then Use the exec() function to execute the OCR command and save the converted results to the output.txt file. Finally, use the fread() function to read the output.txt file and display it.

In summary, the application of OCR technology in PHP can help us automatically process image and text information and improve work efficiency. The emergence of the Tesseract OCR engine further promotes the development and application of OCR technology, making it more convenient to use OCR technology in PHP.

The above is the detailed content of OCR technology and its application in PHP. For more information, please follow other related articles on the PHP Chinese website!