Add Fisheye calibration tool

[DavidTorresOcana]

This PR introduces changes to be able to calibrate fisheye cameras and aim to Fix #146

This PR is related with ros/common_msgs#151 , ros-perception/vision_opencv#306 and ros-perception/image_common#146

Main changes it introduces are:

• Upgrade current calibration tool to:
  • Allow user select between pinhole and fisheye model
  • Calibrate Monocular and Stereo with fisheye model

[DavidTorresOcana]

Hello
With respect this calibration tool, I though to put it together but I do not know how to modify the application GUI. I hope somebody can help on this.
With respect calibration, when you try: Depending on the camera, results would vary. The general recommendation with fisheye is to collect points on the corners of the image.

[DavidTorresOcana]

Looks promising! I think I'll try it out on real data in a few days.
One high-level comment: could the new functionality be merged into the existing respective packages instead of creating new ones? Even better if it's possible to merge it into the existing nodes instead of adding new ones as well.

I mange to find some time to look into this: Modifications done.

[SteveMacenski]

Just come cleanup. I also noticed you changed the permissions on a bunch of files, why is that necessary?

[SteveMacenski]

Last issue. Please also articulate how you tested this since there is no test coverage

[DavidTorresOcana]

Last issue. Please also articulate how you tested this since there is no test coverage

True: all these features are being tested by live calibration with a real camera.
I would encourage you or anybody else to very it too by calibrating a camera.

[DavidTorresOcana]

Commit bc4f2e3 introduces fisheye calibration flags as input arguments.
The proposed input arguments are:

Options:
  -h, --help            show this help message and exit
  -c CAMERA_NAME, --camera_name=CAMERA_NAME
                        name of the camera to appear in the calibration file

  Chessboard Options:
    You must specify one or more chessboards as pairs of --size and
    --square options.

    -p PATTERN, --pattern=PATTERN
                        calibration pattern to detect - 'chessboard',
                        'circles', 'acircles'
    -s SIZE, --size=SIZE
                        chessboard size as NxM, counting interior corners
                        (e.g. a standard chessboard is 7x7)
    -q SQUARE, --square=SQUARE
                        chessboard square size in meters

  ROS Communication Options:
    --approximate=APPROXIMATE
                        allow specified slop (in seconds) when pairing images
                        from unsynchronized stereo cameras
    --no-service-check  disable check for set_camera_info services at startup
    --queue-size=QUEUE_SIZE
                        image queue size (default 1, set to 0 for unlimited)

  Calibration Optimizer Options:
    --pinhole-fix-principal-point
                        for pinhole, fix the principal point at the image
                        center
    --pinhole-fix-aspect-ratio
                        for pinhole, enforce focal lengths (fx, fy) are equal
    --pinhole-zero-tangent-dist
                        for pinhole, set tangential distortion coefficients
                        (p1, p2) to zero
    --pinhole-k-coefficients=NUM_COEFFS
                        for pinhole, number of radial distortion coefficients
                        to use (up to 6, default 2)
    --fisheye-recompute-extrinsicsts
                        for fisheye, extrinsic will be recomputed after each
                        iteration of intrinsic optimization
    --fisheye-fix-skew  for fisheye, skew coefficient (alpha) is set to zero
                        and stay zero
    --fisheye-fix-principal-point
                        for fisheye,fix the principal point at the image
                        center
    --fisheye-k-coefficients=NUM_COEFFS
                        for fisheye, number of radial distortion coefficients
                        to use fixing to zero the rest (up to 4, default 4)
    --fisheye-check-conditions
                        for fisheye, the functions will check validity of
                        condition number
    --disable_calib_cb_fast_check
                        uses the CALIB_CB_FAST_CHECK flag for
                        findChessboardCorners
    --max-chessboard-speed=MAX_CHESSBOARD_SPEED
                        Do not use samples where the calibration pattern is
                        moving faster                      than this speed in
                        px/frame. Set to eg. 0.5 for rolling shutter cameras. 

[SteveMacenski]

OK if tested on hardware I'm OK with that.

You broke backwards compatibility with the flag updates, we need another solution to that. I think just no qualifiers is fine since that's what OpenCV does anyhow and fisheye is specified

[SteveMacenski]

@JWhitleyAStuff take a look

[JWhitleyWork]

See comments.