What is the difference between imagecreateformjpeg and imagecreate for a new PHP image?

What is the difference between imagecreateformjpeg and imagecreate for new PHP plotting? & Lt ;? Phpheader ("content-type: image/gif"); & nbsp; // define the output as image type. what is the difference between imagecreateformjpeg and imagecreate in PHP drawing?
Header ("content-type: image/gif"); // defines the output as an image type.
$ Im = imagecreatefromjpeg ("bg.jpg"); // load the photo
$ Textcolor = imagecolorallocate ($ im, 56,73, 136); // set the font color to blue and the value to RGB.
$ Fnt = "c:/windows/fonts/simhei. ttf"; // define the font
$ Text = iconv ("gb2312", "UTF-8", "Dandong Broken Bridge"); // Convert Chinese to UTF-8 format
ImageTTFText ($ im, 30, 0, 150,120, $ textcolor, $ fnt, $ text); // write TTF text to the graph
Imagegif ($ im); // create a gif image
ImageDestroy ($ im); // ends the image and releases the memory space.
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In the above example
$ Im = imagecreatefromjpeg ("bg.jpg"); // load the photo
Change
$ Im = imagecreate (200,100 );
An error occurs. Why? I just want to change the background image to a custom box. Share PHP graphics:
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One is loaded from an image, and the other is completely self-painted.
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After testing, your code has no syntax error.
The background color is not set.