opencv+aravis

[vahidVision]

hi
thank you for you nice code but i have some problem with it
i use usb3vision camera
the aravis detect my camera and grab frame with readFrameIPL()
when i print framebuffer on readFrameIPL()

(
framebuffer = (void*)arv_buffer_get_data(_buffer, &buffer_size);
std::cout<<buffer_size<<std::endl;/// i add this line
arv_stream_push_buffer(stream, _buffer);
)
1.
my resolution is (2592 * 2048)
print 5308416 continuously (2592 * 2048) that
seems it is GreyScale because RGB should
be(2592 * 2048 * 3) not 2592 * 2048 =5308416
why it grab Grey frame?
2.on Opencv window the full noisy image without any recognizable video content is shown continuously !!! i dont why?

3 . why use this size cvSize(1280, 960) on output video
best regards