Yes, you can organise a combined photo and video contest. Participants can submit photos and videos in the same contest. In the contest gallery, you'll be able to see both photos and videos.
If you combine photo and video formats in your upload campaign, you will be able to choose the types of content you want to allow and it will display in the gallery:
Allowed file types: JPG, PNG, GIF, WEBP, MP3, QT, MPEG, MP4, OGV, MOV, WMV, AVI, 3GP, MKV, MXF, MTS, M2TS, DOC, DOCX, XLS, XLSX, PPT, PPTX, PDF, PSD, AI, ZIP, RAR.
You can thus combine content types to run a combined photo and video campaign.