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2011-11-03 08:07:45 -0500 marked best answer how to make template images for pr2_plugs_actions

Hi, if you want to add a new outlet template, you might want to look at pr2_plugs_actions/outlet_templates/configs for examples of existing templates and generate a new one. I am not sure I understand the PCA-SIFT part of the question. The last time I saw outlet detection, it was using one way descriptors. If you want to replace that with PCA-SIFT, take a look at outlet_template_t class from outlet_pose_estimation package.

2011-10-13 23:20:54 -0500 asked a question pcl_ros manifest.xml changes

In the diamondback , pcl_ros's manifest.xml says

 <cpp cflags="-I${prefix}/include -I${prefix}/msg_gen/cpp/include -I${prefix}/cfg/cpp" lflags="-Wl,-rpath,${prefix}/lib -L${prefix}/lib -lpcl_ros_io -lpcl_ros_features -lpcl_ros_filters -lpcl_ros_segmentation -lpcl_ros_surface -lpcl_ros_tf"/>

In the electric , pcl_ros's manifest.xml says

 <cpp cflags="-I${prefix}/include -I${prefix}/cfg/cpp" lflags="-Wl,-rpath,${prefix}/lib -L${prefix}/lib -lpcl_ros_tf" /> `

and the former flag options were uncommented. I wonder why it had changed.

2011-08-08 11:28:03 -0500 marked best answer changing binning_x,binning_y

No. Color cameras generally work by imposing a Bayer pattern on the image sensor, where each pixel is covered by a filter so that it detects only one color channel (red, green or blue). For example, an RGGB Bayer camera gives you raw images laid out like this:

RG  RG  RG  RG  ...
GB  GB  GB  GB  ...

RG  RG  RG  RG  ...
GB  GB  GB  GB  ...

This is a one-channel image, where each pixel only has information about a single color. Transforming the raw Bayer image into a normal, 3-channel color image is called debayering. There are numerous debayering algorithms of varying sophistication, but the idea is always to interpolate the missing color data from nearby pixels. In ROS, debayering is performed by image_proc.

Binning changes how the camera accumulates the charge at each pixel. With 2x2 binning, 2x2 blocks of pixels are combined into super-pixels using the summed charges of the 4 actual pixels. In this case, every 2x2 Bayer pattern block gets averaged into a monochrome super-pixel:

M M M M ...
M M M M ...

M M M M ...
M M M M ...

You no longer have distinct samples for each color in the raw image.

There are some cameras with a "color binning" feature, which use more complicated circuitry to accumulate each color separately and thus preserve the Bayer pattern in the binned image. As far as I know there aren't any Prosilica cameras with this feature.

2011-08-02 17:57:53 -0500 asked a question changing binning_x,binning_y

Hi,

When I change the binning_x and binning_y of prosilica_driver from reconfigure_gui, the color of image_raw turns to black and white. Are there are any ways to keep image_raw colored when I change binnings?

Thanks in advance,

2011-08-02 17:51:37 -0500 answered a question Using rosservice from webui

Hi,

I finally found the solution. gPump.service_call2() works fine with this problem.

Thanks, H. Chen

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2011-06-17 11:14:09 -0500 marked best answer Using rosservice from webui

Webui was, at one point, for "internal use only". At this point it is completely unsupported...

2011-06-14 17:47:32 -0500 marked best answer how to launch program out-side ros package from launch file

I don't think there is a direct way to achieve this. But you could easily write a wrapper script and put it into a ros package. The script could look like this:

#!/bin/bash
exec $1 ${@:2}

A corresponding launch entry, assuming that the script is called launch_system_cmd.sh and lies in package mypackage, would look like this:

<node name="shell_cmd" type="launch_system_cmd.sh" pkg="mypackage"
      args="/bin/echo foo" />

Please note that roslaunch will pass an additional parameter that sets the name for nodes and if necessary topic remappings. The output of the above command should be something like

foo __name:=shell_cmd

You might need to extend the wrapper script to get rid of those additional parameters.

2011-06-09 16:26:43 -0500 asked a question how to launch program out-side ros package from launch file

Are there any way to start a program in /usr/local/bin from launch file?

2011-05-09 22:28:00 -0500 received badge  Editor (source)
2011-05-09 22:26:16 -0500 asked a question how to make template images for pr2_plugs_actions

Hi,

Does anyone know how to build PCA-SIFT descriptors in pr2_plugs_actions/outlet_template? We want to add new outlet template in our building.

Thanks

Chen Cheng

2011-05-08 21:56:11 -0500 asked a question Using rosservice from webui

Hi

Does anyone have tried to change parameter of dynamic_reconfigure from webui?

For example , I could't figure out how to change prosilica_diver/set_parameters. Of course I can change it from command line like below.

   rosservice call /prosilica_driver/set_parameters '{config:{ints:[[x_offset,0],[y_offset,0],[width,0],[height,0]]}}'

but calling from webui(ros.js) as followings did not works.

    gPump.service_call("prosilica_driver/set_parameters",
                       [[["auto_exposure",true]],
                        [["x_offset",pxoffset]],
                        [["trigger_mode","polled"]],
            [["trig_rate",15.0]]
                        ]);

thanks,