使用imagejpeg

Question

我已经接近完成了这件事（我现在已经尝试了几天），但却遇到了一个奇怪的错误。

此代码复制服务器上的图像并将其大小调整为一半，这在页面的简化版本上可以正常工作：

    $percent = 0.5;
list($width, $height) = getimagesize($output_filename);
$newwidth = $width * $percent;
$newheight = $height * $percent;
$thumb = imagecreatetruecolor($newwidth, $newheight);
$source = imagecreatefromjpeg($output_filename);
imagecopyresized($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);
imagejpeg($thumb, $output_filename_new, $jpeg_quality);

这很好用，但是当我将它添加到上传图像的页面时，首先复制/调整大小的位不起作用。

我认为在上传图片后它会丢失$ strName（上一页为$ _POST），如果我手动添加文件名，并使用字符串作为其工作的文件名。

这是在应该复制图像的代码之前上传图像的代码：

// resize the original image to size of editor
$resizedImage = imagecreatetruecolor($imgW, $imgH);
imagecopyresampled($resizedImage, $source_image, 0, 0, 0, 0, $imgW, $imgH, $imgInitW, $imgInitH);
// rotate the rezized image
$rotated_image = imagerotate($resizedImage, -$angle, 0);
// find new width & height of rotated image
$rotated_width = imagesx($rotated_image);
$rotated_height = imagesy($rotated_image);
// diff between rotated & original sizes
$dx = $rotated_width - $imgW;
$dy = $rotated_height - $imgH;
// crop rotated image to fit into original rezized rectangle
$cropped_rotated_image = imagecreatetruecolor($imgW, $imgH);
imagecolortransparent($cropped_rotated_image, imagecolorallocate($cropped_rotated_image, 0, 0, 0));
imagecopyresampled($cropped_rotated_image, $rotated_image, 0, 0, $dx / 2, $dy / 2, $imgW, $imgH, $imgW, $imgH);
// crop image into selected area
$final_image = imagecreatetruecolor($cropW, $cropH);
imagecolortransparent($final_image, imagecolorallocate($final_image, 0, 0, 0));
imagecopyresampled($final_image, $cropped_rotated_image, 0, 0, $imgX1, $imgY1, $cropW, $cropH, $cropW, $cropH);
// finally output png image
//imagepng($final_image, $output_filename.$type, $png_quality);
imagejpeg($final_image, $output_filename.$type, $jpeg_quality);
imagedestroy($final_image);




$percent = 0.5;
list($width, $height) = getimagesize($output_filename);
$newwidth = $width * $percent;
$newheight = $height * $percent;
$thumb = imagecreatetruecolor($newwidth, $newheight);
$source = imagecreatefromjpeg($output_filename);
imagecopyresized($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);
imagejpeg($thumb, $output_filename_new, $jpeg_quality);