IMG_RESOURCE

Objects of type IMG_RESOURCE returns a reference to an image, possibly wrapped with Properties. It can be used, for example, for putting background images in tables or table rows or to import an image in your own include scripts.

The array $GLOBALS['TSFE']->lastImgResourceInfo is set to the info array of the resulting image resource (if any) and contains width, height and so on (similar to how $GLOBALS['TSFE']->lastImageInfo does for the cObject IMAGE).

Depending on your use case you might prefer using the cObject IMAGE, which creates a complete img tag.