Changing pixel size of a URDF camera

edit

How do I change the pixel size of my URDF camera?

Anyone knows?

For example for this urdf file:

<gazebo reference="camera_link">
<sensor type="camera" name="camera1">
  <update_rate>30.0</update_rate>
  <camera name="head">
    <horizontal_fov>1.3962634</horizontal_fov>
    <image>
      <width>1000</width>
      <height>900</height>
      <format>R8G8B8</format>
    </image>
    <clip>
      <near>0.02</near>
      <far>500</far>
    </clip>
    <noise>
      <type>gaussian</type>
      <!-- Noise is sampled independently per pixel on each frame.
           That pixel's noise value is added to each of its color
           channels, which at that point lie in the range [0,1]. -->
      <mean>0.0</mean>
      <stddev>0.007</stddev>
    </noise>
  </camera>
  <plugin name="camera_controller" filename="libgazebo_ros_camera.so">
    <alwaysOn>true</alwaysOn>
    <updateRate>0.0</updateRate>
    <cameraName>p3dx/camera1</cameraName>
    <imageTopicName>image_raw</imageTopicName>
    <cameraInfoTopicName>camera_info</cameraInfoTopicName>
    <frameName>camera_link</frameName>
    <hackBaseline>0.07</hackBaseline>
    <distortionK1>0.0</distortionK1>
    <distortionK2>0.0</distortionK2>
    <distortionK3>0.0</distortionK3>
    <distortionT1>0.0</distortionT1>
    <distortionT2>0.0</distortionT2>
  </plugin>
</sensor>

</gazebo>

I was trying to change the image width and hight but that just makes my image bigger not change the pixel size.

Thx so much friends.