Do I need credits for using VanceAI PC to process pictures?

No.

VanceAI PC is a client software that runs on your computer. It uses your computer's GPU or CPU to process images, so it does not need to consume credits. Your pictures will not be uploaded to the cloud server, and the speed of processing pictures varies according to your computer's hardware. Generally speaking, the better the GPU performance, the faster the image processing speed will be. For the requirements of VanceAI PC for your computer hardware please check here