How to use "-batchmode" command line argument for standalone player?

Hi:
my app doing off-screen rendering, it render scene to a RenderTexture binded to main Camera, then use a native plugin to read out the rendered image; it works well when my app is started without any arguments,but when I run my app in “headless” mode with “-batchmode” argument, the readout image is all black(include alpha channel);
I think display window is not necessary for my app, so “-batchmode” argument should be used, but why the readout image is black when the argument is used? How do I modify the script to adapt it?

Same demand, same issue. Additionaly, my native plugin make the Unity standalone player display a windows with its content all wihte, dispite I launch it in batchmode.