[JdeRobot] Compressed Images

[Roberto Calvo]

El lun, 30-03-2015 a las 13:18 +0200, Oscar Garcia escribió:
> Implement image compression not implied redactor or modify Image
> interface. I explained it in previous message. Only is needed to
> modify color spaces. Format used in image is sent inside
> ImageDescription.

Oscar,

I'm going to try explain what it's the problem and the solution that we
adopted. 

Just think about this scenario. We need that one instance of server
(just one) provides several formats at the same time. Imagine three
clients ask to server about RGB8, RGB8_Z and NV21 format images (for
instance). If cameraserver provides always NV21 format (using
colorspaces), how other client can ask about RGB8_Z? 

There is no way to do that if the client doesn't specify the format that
it wants. Until now, the cameraserver always sent the same format image
to every clients, and this is a problem. What does the server decide if
it has to send a compress image or regular image? Just the client tell
it with this new parameter.

We had this idea two years ago, but we know that modify the interfaces
always have a huge cost. But, right now it's necessary to provide more
functionality and flexibility to JdeRobot.

Just think about it. The server has to provide several image formats to
different clients at the same time. Just we know twice solutions: create
a new method getImageDataFormat(format), or modify the getImageData()
method to add the format that the client wants. 

I want to be clear what is the problem about compressed images, and if
someone has a great solution is welcome, no doubt it! But, think in the
scenario I told you.

Best,

-- 
Roberto Calvo Palomino        | Robotics Lab (GSyC) 
R&D Android Mobile Engineer   | Universidad Rey Juan Carlos

Twitter: @rocapal 
Linkedin: http://www.linkedin.com/in/rocapal