If you don't mind feature bloat. The GIMP If you want to try a specialized tool. PicGhost If you don't mind the command line*. ffmpeg for video, imagemagik for images. From any of several programming languages. GD. From Javascript. Web Canvas *. big "if", I know
STEP 1: Simply download PDF element from Apple's App Store/Google Play. STEP 2: Once downloaded, launch PDF element and click on the blue button named Add to bookstore. STEP 5: Once the add button appears, click on bookstore to confirm whether you would like to add the PDF to Apple's bookstore or not. STEP 6: Now, you can view the PDF document or the PDF file you would like to add/remove watermark from. Click on the green Add button and select a PDF file or the entire document (from left-to-right). STEP 7: On the screen which appears, drag the watermark to any empty area of the page. STEP 8: Once the watermark is added, simply click on the Apply button. Alternatively, you can simply tap on the blue arrow icon on the right-to-left side of the watermark and tap on Edit. STEP 9: From the drop-down menu, you can see options to Edit/Remove Watermark. Please note, that for adding.