【发布时间】：2020-01-13 03:51:17
【问题描述】：
我正在使用 Ghostscript 9.50 和 ImageMagick 7.0.9 从上传的 PDF 文档生成首页缩略图。
这是我从 http://www.rainbodesign.com/pub/image-tools/pdf-to-jpg.html 获得的代码，然后我将其用作电子书控制器中的函数
function thumbnail(){
$pdfPath = $_SERVER['DOCUMENT_ROOT'] . str_replace(basename($_SERVER['SCRIPT_NAME']),"",$_SERVER['SCRIPT_NAME']); // Path to PDF files on the server
$imagesPath = $_SERVER['DOCUMENT_ROOT'] . str_replace(basename($_SERVER['SCRIPT_NAME']),"",$_SERVER['SCRIPT_NAME']) . 'ebooks/'; // Path to your images directory on the server
$thumbsPath = $imagesPath . 'thumbnails/'; // Path to image thumbnails directory
$thumbsize = 250; // Width of thumbnail images (set to 0 for full size)
$pageNo = 0; // Page # from PDF to convert (ordinal!)
// Constants and Defaults
// ----------------------
$theWMType = 'jpg:';
$extension = '.jpg';
$pdf = '';
$error = '';
// Fetch user settings and default overrides via query string
if (isset($_GET['src'])) { $pdf = $_GET['src']; }
if (isset($_GET['path'])) { $pdfPath = $_SERVER['DOCUMENT_ROOT'] . '/' . $_GET['path']; }
if (isset($_GET['width'])) { $thumbsize = $_GET['width']; }
if (isset($_GET['page'])) { $pageNo = $_GET['page'] - 1; } // Page # is ordinal in ImageMagick!
if ($pdf == '') { $error .= "Source Image Not Specified.<br>\n"; }
$original = $pdfPath . $pdf; // Add file path to PDF file name
$originalBase = basename($pdf,'.pdf'); // Extract PDF file name basename w/o extension
$thumbnail = $thumbsPath . $originalBase . $extension; // Use basename for the thumbnail .jpg file name
if (!file_exists($original)) { // Make sure PDF file exists
$error .= "Source PDF Document Not Found<br>\n" . $original . "<br>\n";
}
// Fix file name(s) to select 1st page of PDF and enquote $original if it/they contain <space>s.
if (strpos($original, ' ') !== false) {
$original = "\"" . $original . "[$pageNo]\""; // Enclose file name in quotes and add Page #
$thumbnail = str_replace(' ', '_', $thumbnail); // Replace <space>s with underscores
} else {
$original = $original . "[$pageNo]"; // Just add Page # to PDF $original
}
// Check to see if the thumbnail already exists in the "cache"
if (!file_exists($thumbnail)) {
// No! Convert PDF to JPG with ImageMagick/GhostScript now!
if ($error == '') {
$wmCmd = "convert $original";
if ($thumbsize != 0) { $wmCmd .= " -resize " . $thumbsize . "x"; }
$wmCmd .= " $theWMType$thumbnail";
$result = exec($wmCmd);
} // endif $error == ''
// A little error-checking overkill
if (!file_exists($thumbnail)) {
$error .= "Convert Failed! Can't find $thumbnail<br>\n";
$error .= $result . "<br>\n" . $original . "<br>\n" . $thumbnail . "<br>\n";
} // endif !file_exists
} // endif !file_exists($thumbnail)
if ($error != '') { // Did we see an error?
header("Content-type: text/html\n"); // Yes! Send MIME-type header for HTML files
echo($error);
} else {
header("Content-type: image/jpeg\n"); // No. OK, send MIME-type header for JPEG files
echo(file_get_contents($thumbnail)); // Fetch image file contents and send it!
} // endif $error
exit;
}
但是当我想在那里显示缩略图时：
<img src="<?= base_url('ebook/thumbnail?src=ebooks/' . $e->file) ?>" width="100" alt="pdf document">
图片无法显示，当从浏览器中的 img 标签“src”加载 URL 进行检查时，出现此错误：
Convert Failed! Can't find D:/htdocs/halokes_library/ebooks/thumbnails/XML_Bible.jpg
D:/htdocs/halokes_library/ebooks/XML_Bible.pdf[0]
D:/htdocs/halokes_library/ebooks/thumbnails/XML_Bible.jpg
有什么想法吗？
【问题讨论】：
-
你确定路径正确吗？
-
您引用了您自己的代码中的错误。从 ImageMagick 捕获错误会更有用，或者更好的是从 Ghostscript 捕获错误/警告消息。
-
@SimoneRossaini 是的，路径是正确的
-
@chrisl 我从浏览器中捕获了该错误。我无法从 ImageMagick 或 Ghostscript 捕获错误，因为转换是通过此 PHP 代码执行的（不直接使用 Ghostscript CLI 或 ImageMagick 应用程序）
-
好吧，我能建议的最好的方法是仔细检查 PHP 运行命令的环境： PHP 通常在特殊用户下运行，并且通常 PATH 环境变量未设置为“正常”用户。值得仔细检查。
标签： php codeigniter imagemagick ghostscript