merge into one pdf multiple items at once join lines into one joining pdfs into one merge multiple pages into one join pngs and jpgs into one merge excel files into one all at once all+at+once+using+photoshop all into one all at once using photoshop all+at+once all together into one image merge 2 pdf pages into one sound into one join many images into one file merge lines into one line merge audio into one several files at once appending oggs