Batch Video Watermark

I have 50 mp4 videos, about 2 min each, and around 25mb each. I need these watermarked. I have a png watermark. You are required to use some batch watermarking software such as watermark pro, or a plugin for premier. The videos need to be outputted the same quality as the original. When all are watermarked, they need to be zipped up and uploaded to drop box. This is a simple job, the time it takes will depend on your internet connection and processing speed of your pc/mac. THIS JOB SHOULD TAKE NO MORE THAN 1 HOUR's WORK. I DO NOT WANT THESE DONE MANUALLY... ONLY A BATCH PROCESS.