Download image from SLR camera via arduino using USB wiring

I have a SRL camera with a USB port (PINOUT A) to download the image file from the camera storage card. The same camera has a second pinout plug (PINOUT B) for remote shooting.

Arduino controls the shooting via the PINOUT B. But I do not know how to plug the USB from plug A to Arduino to capture the image file and uploaded to the computer.

Plugging the USB directly to the computer does not help because the camera shutter is dissable whenever senses power from the USB port. This only left me with the option to connect the USB to the arduino that can control the power on/Off to the usb but dont know how to to the upload to the computer.