How to create a new image from a JPEG file using the imagecreatefromjpeg() function in PHP?

The imagecreatefromjpeg() function is an inbuilt PHP function that creates a new image resource from a JPEG file. It returns an image identifier representing the image obtained from the given filename.

Syntax

resource imagecreatefromjpeg(string $filename)

Parameters

$filename − The name or path to the JPEG image file to be loaded.

Return Value

Returns an image resource identifier on success, or false on failure.

Note: This function requires the GD extension to be enabled in PHP.

Example 1 − Basic Image Loading and Display

The following example shows how to load a JPEG image and display it in the browser ?

<?php
   // Load an image from file
   $img = imagecreatefromjpeg('/path/to/image.jpg');
   
   // Set the content type header for JPEG
   header('Content-type: image/jpeg');
   
   // Output the image to browser
   imagejpeg($img);
   
   // Free up memory
   imagedestroy($img);
?>

Example 2 − Image Processing with Flip

This example demonstrates loading a JPEG image, applying a flip transformation, and saving the result ?

<?php
   // Load a JPEG image from file
   $img = imagecreatefromjpeg('/path/to/input.jpg');
   
   // Flip the image horizontally
   imageflip($img, IMG_FLIP_HORIZONTAL);
   
   // Save the modified image
   imagejpeg($img, '/path/to/output.jpg');
   
   // Clean up memory
   imagedestroy($img);
?>

Example 3 − Error Handling

This example shows how to handle errors when loading JPEG files ?

<?php
   function LoadJpeg($imgname) {
      // Attempt to open the image
      $im = @imagecreatefromjpeg($imgname);
      
      // Check if loading failed
      if(!$im) {
         // Create a fallback image
         $im = imagecreatetruecolor(700, 300);
         $bgc = imagecolorallocate($im, 0, 0, 255);
         $tc = imagecolorallocate($im, 255, 255, 255);
         imagefilledrectangle($im, 0, 0, 700, 300, $bgc);
         
         // Display error message on image
         imagestring($im, 5, 80, 140, 'Error loading ' . $imgname, $tc);
      }
      return $im;
   }

   // Set content type
   header('Content-Type: image/jpeg');
   
   // Load image with error handling
   $img = LoadJpeg('nonexistent.jpg');
   imagejpeg($img);
   imagedestroy($img);
?>

Key Points

Conclusion

The imagecreatefromjpeg() function is essential for loading JPEG images in PHP for further processing. Always implement proper error handling and remember to free memory with imagedestroy().