Answer
For an image annotation object in a PDF file, you can lock its aspect ratio by following these steps:
1.Go to the "Edit" tab in Foxit PDF Editor, then select "Select" and choose "Select Annotation". Right-click on the image annotation object and select the "Properties" option from the context menu to open the "Image Properties" dialog box.
2. In the "Image Properties" dialog box, click on the "Settings" tab, then click on the "Advanced" button to open the "Image Placement" dialog box. Choose "Proportionally" for the Scale option from the drop-down menu, click "OK" to close the "Image Properties" dialog box, and then click on the "Close" button in the dialog box to close it.
3.Then you can then use the Hand tool or the Select Annotation tool to click on the image annotation, and drag one of the resize handles outwards or inwards to resize the image proportionally without changing its aspect ratio.
For an image object in a PDF file, you cannot directly lock its aspect ratio. However, you can maintain the image aspect ratio when adjusting its size by following these steps:
1.Go to the "Edit" tab in Foxit PDF Editor and select the "Edit Object" > "Image" tool.
2. Single-click on the image object to select it, then drag one of the four corner resize handles outwards or inwards to resize the image proportionally. If you use the other resize handles (left & right or top & bottom), you can also hold down the SHIFT key on the keyboard to resize it proportionally without changing its aspect ratio.