Why my depth map is so bad ?

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Hello,

I don't know if it's normal to obtain this kind of depth map ? Can you tell me ?

What I did is the following: i have dataset with left and right image. Thank to stereo_image_proc, I obtained the pointCloud2 and disparity image. (I can't know if my disparity image is valid because image_view crash and i can't see with rqt_image_view)

Then I transformed the Disparity Image to Depth Map thank to this node https://github.com/skohlbr/disparity_...

But I obtain a very weird result: http://hpics.li/74b5c6f

Do you know why ? And especially how i can solve this problem ?

Many thank,