In what scenarios should PHP developers consider using imagecreatefromjpeg() and imagejpeg() functions for displaying images in PHP applications, and how can they ensure proper implementation for optimal performance?

When displaying images in PHP applications, developers should consider using the imagecreatefromjpeg() and imagejpeg() functions for JPEG images. These functions allow for the creation of image resources from JPEG files and the output of JPEG images, respectively. To ensure optimal performance, developers should properly handle errors, free up memory after image processing, and consider caching images to reduce load times.

// Example code snippet for displaying a JPEG image using imagecreatefromjpeg() and imagejpeg()

// Path to the JPEG image file
$imageFile = 'path/to/image.jpg';

// Create image resource from JPEG file
$image = imagecreatefromjpeg($imageFile);

// Output the image to the browser or save it to a file
header('Content-Type: image/jpeg');
imagejpeg($image);

// Free up memory
imagedestroy($image);