Change the image in the run time using appium

Hi,

I have a requirement to automate the capturing of check image. As we cannot capture the check using automation in real time, i thought of taking the picture with out the check that will give me a dummy image and now the screen is displayed with some dummy image .so is it possible to put the check image in place of dummy image using appium.if so can you please help me how to do that or any other suggestions to achieve capturing of check

below is what i got after capturing the dummy image.

I want to change the above image to below using appium.