How to achieve a value of a multi-type message mesage ?

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Dear friends,

I am trying to Subscribe from a topic, this topic has been published by CMVISION (/blobs) and has this type :

Header header uint32 image_width uint32 image_height uint32 blob_count Blob[] blobs

and in this type, "Blob" is another message type itself : uint32 red uint32 green uint32 blue uint32 area uint32 x uint32 y uint32 left uint32 right uint32 top uint32 bottom

I want to subscribe the "x" and "y" from this message, but I dont know hoe to call that,

For example I want to write them on the terminal and in my "callback" function I wrote :

void callback1(const cmvision::Blobs::ConstPtr& msg1) {

ROS_INFO("I heard: [%d]", msg1->blobs ??????);

}

I tried to call that like an array, it didn't work.... can any body help me in this problem?

Thanks HAmed