gstreamer/ext/opencv/gstcameracalibrate.cpp
2020-06-06 00:40:42 +02:00

769 lines
27 KiB
C++

/*
* GStreamer
* Copyright (C) <2017> Philippe Renon <philippe_renon@yahoo.fr>
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
* Alternatively, the contents of this file may be used under the
* GNU Lesser General Public License Version 2.1 (the "LGPL"), in
* which case the following provisions apply instead of the ones
* mentioned above:
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:element-cameraundistort
*
* This element performs camera calibration.
*
* Once the calibration procedure is done:
* - An event, containing the camera correction parameters, is sent upstream
* and downstream to be consumed by cameraundistort elements.
* - The _settings_ property is set to the camera correction parameters (as
* an opaque string of serialized OpenCV objects).
* The value of this property can later be used to configure a
* cameraundistort element.
* - The element becomes idle and can later be restarted [TODO].
*
* Based on this tutorial: https://docs.opencv.org/2.4/doc/tutorials/calib3d/camera_calibration/camera_calibration.html
*
* ## Example pipelines
*
* |[
* gst-launch-1.0 -v v4l2src ! videoconvert ! cameraundistort ! cameracalibrate | autovideosink
* ]| will correct camera distortion once camera calibration is done.
*/
/*
* TODO
* - signal when calibration is done
* - action signal to start calibration
* - do pattern detection asynchronously
* - do final calibration computation asynchronously
* - use cairo for drawing overlay
* - use overlay
* - implement settings query
* - validate user settings (see validate() in tutorial)
* - save complete state (see saveCameraParams() in tutorial)
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "gstcameracalibrate.h"
#include <opencv2/imgproc.hpp>
#include <opencv2/calib3d.hpp>
#include <gst/opencv/gstopencvutils.h>
#include "camerautils.hpp"
#include "cameraevent.hpp"
#include <vector>
GST_DEBUG_CATEGORY_STATIC (gst_camera_calibrate_debug);
#define GST_CAT_DEFAULT gst_camera_calibrate_debug
#define DEFAULT_CALIBRATON_PATTERN GST_CAMERA_CALIBRATION_PATTERN_CHESSBOARD
#define DEFAULT_BOARD_WIDTH 9
#define DEFAULT_BOARD_HEIGHT 6
#define DEFAULT_SQUARE_SIZE 50
#define DEFAULT_ASPECT_RATIO 1.0
#define DEFAULT_CORNER_SUB_PIXEL true
#define DEFAULT_ZERO_TANGENT_DISTORTION FALSE
#define DEFAULT_CENTER_PRINCIPAL_POINT FALSE
#define DEFAULT_USE_FISHEYE FALSE
#define DEFAULT_FRAME_COUNT 25
#define DEFAULT_DELAY 350
#define DEFAULT_SHOW_CORNERS true
enum
{
PROP_0,
PROP_CALIBRATON_PATTERN,
PROP_BOARD_WIDTH,
PROP_BOARD_HEIGHT,
PROP_SQUARE_SIZE,
PROP_ASPECT_RATIO,
PROP_CORNER_SUB_PIXEL,
PROP_ZERO_TANGENT_DISTORTION,
PROP_CENTER_PRINCIPAL_POINT,
PROP_USE_FISHEYE,
PROP_FRAME_COUNT,
PROP_DELAY,
PROP_SHOW_CORNERS,
PROP_SETTINGS
};
enum
{
DETECTION = 0,
CAPTURING = 1,
CALIBRATED = 2
};
#define GST_TYPE_CAMERA_CALIBRATION_PATTERN (camera_calibration_pattern_get_type ())
static GType
camera_calibration_pattern_get_type (void)
{
static GType camera_calibration_pattern_type = 0;
static const GEnumValue camera_calibration_pattern[] = {
{GST_CAMERA_CALIBRATION_PATTERN_CHESSBOARD, "Chessboard", "chessboard"},
{GST_CAMERA_CALIBRATION_PATTERN_CIRCLES_GRID, "Circle Grids",
"circle_grids"},
{GST_CAMERA_CALIBRATION_PATTERN_ASYMMETRIC_CIRCLES_GRID,
"Asymmetric Circle Grids", "asymmetric_circle_grids"},
{0, NULL, NULL},
};
if (!camera_calibration_pattern_type) {
camera_calibration_pattern_type =
g_enum_register_static ("GstCameraCalibrationPattern",
camera_calibration_pattern);
}
return camera_calibration_pattern_type;
}
G_DEFINE_TYPE (GstCameraCalibrate, gst_camera_calibrate,
GST_TYPE_OPENCV_VIDEO_FILTER);
static void gst_camera_calibrate_dispose (GObject * object);
static void gst_camera_calibrate_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_camera_calibrate_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static GstFlowReturn
gst_camera_calibrate_transform_frame_ip (GstOpencvVideoFilter * cvfilter,
GstBuffer * frame, cv::Mat img);
/* clean up */
static void
gst_camera_calibrate_finalize (GObject * obj)
{
G_OBJECT_CLASS (gst_camera_calibrate_parent_class)->finalize (obj);
}
/* initialize the cameracalibration's class */
static void
gst_camera_calibrate_class_init (GstCameraCalibrateClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
GstOpencvVideoFilterClass *opencvfilter_class =
GST_OPENCV_VIDEO_FILTER_CLASS (klass);
GstCaps *caps;
GstPadTemplate *templ;
gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_camera_calibrate_finalize);
gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_camera_calibrate_dispose);
gobject_class->set_property = gst_camera_calibrate_set_property;
gobject_class->get_property = gst_camera_calibrate_get_property;
opencvfilter_class->cv_trans_ip_func =
gst_camera_calibrate_transform_frame_ip;
g_object_class_install_property (gobject_class, PROP_CALIBRATON_PATTERN,
g_param_spec_enum ("pattern", "Calibration Pattern",
"One of the chessboard, circles, or asymmetric circle pattern",
GST_TYPE_CAMERA_CALIBRATION_PATTERN, DEFAULT_CALIBRATON_PATTERN,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)));
g_object_class_install_property (gobject_class, PROP_BOARD_WIDTH,
g_param_spec_int ("board-width", "Board Width",
"The board width in number of items",
1, G_MAXINT, DEFAULT_BOARD_WIDTH,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)));
g_object_class_install_property (gobject_class, PROP_BOARD_HEIGHT,
g_param_spec_int ("board-height", "Board Height",
"The board height in number of items",
1, G_MAXINT, DEFAULT_BOARD_WIDTH,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)));
g_object_class_install_property (gobject_class, PROP_SQUARE_SIZE,
g_param_spec_float ("square-size", "Square Size",
"The size of a square in your defined unit (point, millimeter, etc.)",
0.0, G_MAXFLOAT, DEFAULT_SQUARE_SIZE,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)));
g_object_class_install_property (gobject_class, PROP_ASPECT_RATIO,
g_param_spec_float ("aspect-ratio", "Aspect Ratio",
"The aspect ratio",
0.0, G_MAXFLOAT, DEFAULT_ASPECT_RATIO,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)));
g_object_class_install_property (gobject_class, PROP_CORNER_SUB_PIXEL,
g_param_spec_boolean ("corner-sub-pixel", "Corner Sub Pixel",
"Improve corner detection accuracy for chessboard",
DEFAULT_CORNER_SUB_PIXEL,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)));
g_object_class_install_property (gobject_class, PROP_ZERO_TANGENT_DISTORTION,
g_param_spec_boolean ("zero-tangent-distorsion",
"Zero Tangent Distorsion", "Assume zero tangential distortion",
DEFAULT_ZERO_TANGENT_DISTORTION,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)));
g_object_class_install_property (gobject_class, PROP_CENTER_PRINCIPAL_POINT,
g_param_spec_boolean ("center-principal-point", "Center Principal Point",
"Fix the principal point at the center",
DEFAULT_CENTER_PRINCIPAL_POINT,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)));
g_object_class_install_property (gobject_class, PROP_USE_FISHEYE,
g_param_spec_boolean ("use-fisheye", "Use Fisheye",
"Use fisheye camera model for calibration",
DEFAULT_USE_FISHEYE,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)));
g_object_class_install_property (gobject_class, PROP_DELAY,
g_param_spec_int ("delay", "Delay",
"Sampling periodicity in ms", 0, G_MAXINT,
DEFAULT_DELAY,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)));
g_object_class_install_property (gobject_class, PROP_FRAME_COUNT,
g_param_spec_int ("frame-count", "Frame Count",
"The number of frames to use from the input for calibration", 1,
G_MAXINT, DEFAULT_FRAME_COUNT,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)));
g_object_class_install_property (gobject_class, PROP_SHOW_CORNERS,
g_param_spec_boolean ("show-corners", "Show Corners",
"Show corners",
DEFAULT_SHOW_CORNERS,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)));
g_object_class_install_property (gobject_class, PROP_SETTINGS,
g_param_spec_string ("settings", "Settings",
"Camera correction parameters (opaque string of serialized OpenCV objects)",
NULL, (GParamFlags) (G_PARAM_READABLE | G_PARAM_STATIC_STRINGS)));
gst_element_class_set_static_metadata (element_class,
"cameracalibrate",
"Filter/Effect/Video",
"Performs camera calibration",
"Philippe Renon <philippe_renon@yahoo.fr>");
/* add sink and source pad templates */
caps = gst_opencv_caps_from_cv_image_type (CV_8UC4);
gst_caps_append (caps, gst_opencv_caps_from_cv_image_type (CV_8UC3));
gst_caps_append (caps, gst_opencv_caps_from_cv_image_type (CV_8UC1));
templ = gst_pad_template_new ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
gst_caps_ref (caps));
gst_element_class_add_pad_template (element_class, templ);
templ = gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS, caps);
gst_element_class_add_pad_template (element_class, templ);
gst_type_mark_as_plugin_api (GST_TYPE_CAMERA_CALIBRATION_PATTERN, (GstPluginAPIFlags) 0);
}
/* initialize the new element
* initialize instance structure
*/
static void
gst_camera_calibrate_init (GstCameraCalibrate * calib)
{
calib->calibrationPattern = DEFAULT_CALIBRATON_PATTERN;
calib->boardSize.width = DEFAULT_BOARD_WIDTH;
calib->boardSize.height = DEFAULT_BOARD_HEIGHT;
calib->squareSize = DEFAULT_SQUARE_SIZE;
calib->aspectRatio = DEFAULT_ASPECT_RATIO;
calib->cornerSubPix = DEFAULT_CORNER_SUB_PIXEL;
calib->calibZeroTangentDist = DEFAULT_ZERO_TANGENT_DISTORTION;
calib->calibFixPrincipalPoint = DEFAULT_CENTER_PRINCIPAL_POINT;
calib->useFisheye = DEFAULT_USE_FISHEYE;
calib->nrFrames = DEFAULT_FRAME_COUNT;
calib->delay = DEFAULT_DELAY;
calib->showCorners = DEFAULT_SHOW_CORNERS;
calib->flags = cv::CALIB_FIX_K4 | cv::CALIB_FIX_K5;
if (calib->calibFixPrincipalPoint)
calib->flags |= cv::CALIB_FIX_PRINCIPAL_POINT;
if (calib->calibZeroTangentDist)
calib->flags |= cv::CALIB_ZERO_TANGENT_DIST;
if (calib->aspectRatio)
calib->flags |= cv::CALIB_FIX_ASPECT_RATIO;
if (calib->useFisheye) {
/* the fisheye model has its own enum, so overwrite the flags */
calib->flags =
cv::fisheye::CALIB_FIX_SKEW | cv::fisheye::CALIB_RECOMPUTE_EXTRINSIC |
/*cv::fisheye::CALIB_FIX_K1 | */
cv::fisheye::CALIB_FIX_K2 | cv::fisheye::CALIB_FIX_K3 | cv::
fisheye::CALIB_FIX_K4;
}
calib->mode = CAPTURING; //DETECTION;
calib->prevTimestamp = 0;
calib->imagePoints.clear ();
calib->cameraMatrix = 0;
calib->distCoeffs = 0;
calib->settings = NULL;
gst_opencv_video_filter_set_in_place (GST_OPENCV_VIDEO_FILTER_CAST (calib),
TRUE);
}
static void
gst_camera_calibrate_dispose (GObject * object)
{
GstCameraCalibrate *calib = GST_CAMERA_CALIBRATE (object);
g_free (calib->settings);
calib->settings = NULL;
G_OBJECT_CLASS (gst_camera_calibrate_parent_class)->dispose (object);
}
static void
gst_camera_calibrate_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstCameraCalibrate *calib = GST_CAMERA_CALIBRATE (object);
switch (prop_id) {
case PROP_CALIBRATON_PATTERN:
calib->calibrationPattern = g_value_get_enum (value);
break;
case PROP_BOARD_WIDTH:
calib->boardSize.width = g_value_get_int (value);
break;
case PROP_BOARD_HEIGHT:
calib->boardSize.height = g_value_get_int (value);
break;
case PROP_SQUARE_SIZE:
calib->squareSize = g_value_get_float (value);
break;
case PROP_ASPECT_RATIO:
calib->aspectRatio = g_value_get_float (value);
break;
case PROP_CORNER_SUB_PIXEL:
calib->cornerSubPix = g_value_get_boolean (value);
break;
case PROP_ZERO_TANGENT_DISTORTION:
calib->calibZeroTangentDist = g_value_get_boolean (value);
break;
case PROP_CENTER_PRINCIPAL_POINT:
calib->calibFixPrincipalPoint = g_value_get_boolean (value);
break;
case PROP_USE_FISHEYE:
calib->useFisheye = g_value_get_boolean (value);
break;
case PROP_FRAME_COUNT:
calib->nrFrames = g_value_get_int (value);
break;
case PROP_DELAY:
calib->delay = g_value_get_int (value);
break;
case PROP_SHOW_CORNERS:
calib->showCorners = g_value_get_boolean (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_camera_calibrate_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstCameraCalibrate *calib = GST_CAMERA_CALIBRATE (object);
switch (prop_id) {
case PROP_CALIBRATON_PATTERN:
g_value_set_enum (value, calib->calibrationPattern);
break;
case PROP_BOARD_WIDTH:
g_value_set_int (value, calib->boardSize.width);
break;
case PROP_BOARD_HEIGHT:
g_value_set_int (value, calib->boardSize.height);
break;
case PROP_SQUARE_SIZE:
g_value_set_float (value, calib->squareSize);
break;
case PROP_ASPECT_RATIO:
g_value_set_float (value, calib->aspectRatio);
break;
case PROP_CORNER_SUB_PIXEL:
g_value_set_boolean (value, calib->cornerSubPix);
break;
case PROP_ZERO_TANGENT_DISTORTION:
g_value_set_boolean (value, calib->calibZeroTangentDist);
break;
case PROP_CENTER_PRINCIPAL_POINT:
g_value_set_boolean (value, calib->calibFixPrincipalPoint);
break;
case PROP_USE_FISHEYE:
g_value_set_boolean (value, calib->useFisheye);
break;
case PROP_FRAME_COUNT:
g_value_set_int (value, calib->nrFrames);
break;
case PROP_DELAY:
g_value_set_int (value, calib->delay);
break;
case PROP_SHOW_CORNERS:
g_value_set_boolean (value, calib->showCorners);
break;
case PROP_SETTINGS:
g_value_set_string (value, calib->settings);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
void camera_calibrate_run (GstCameraCalibrate * calib, cv::Mat img);
/*
* Performs the camera calibration
*/
static GstFlowReturn
gst_camera_calibrate_transform_frame_ip (GstOpencvVideoFilter * cvfilter,
G_GNUC_UNUSED GstBuffer * frame, cv::Mat img)
{
GstCameraCalibrate *calib = GST_CAMERA_CALIBRATE (cvfilter);
camera_calibrate_run (calib, img);
return GST_FLOW_OK;
}
bool camera_calibrate_calibrate (GstCameraCalibrate * calib,
cv::Size imageSize, cv::Mat & cameraMatrix, cv::Mat & distCoeffs,
std::vector < std::vector < cv::Point2f > >imagePoints);
void
camera_calibrate_run (GstCameraCalibrate * calib, cv::Mat img)
{
// For camera only take new samples after delay time
if (calib->mode == CAPTURING) {
// get_input
cv::Size imageSize = img.size ();
/* find_pattern
* FIXME find ways to reduce CPU usage
* don't do it on all frames ? will it help ? corner display will be affected.
* in a separate frame?
* in a separate element that gets composited back into the main stream
* (video is tee-d into it and can then be decimated, scaled, etc..) */
std::vector < cv::Point2f > pointBuf;
bool found;
int chessBoardFlags =
cv::CALIB_CB_ADAPTIVE_THRESH | cv::CALIB_CB_NORMALIZE_IMAGE;
if (!calib->useFisheye) {
/* fast check erroneously fails with high distortions like fisheye */
chessBoardFlags |= cv::CALIB_CB_FAST_CHECK;
}
/* Find feature points on the input format */
switch (calib->calibrationPattern) {
case GST_CAMERA_CALIBRATION_PATTERN_CHESSBOARD:
found =
cv::findChessboardCorners (img, calib->boardSize, pointBuf,
chessBoardFlags);
break;
case GST_CAMERA_CALIBRATION_PATTERN_CIRCLES_GRID:
found = cv::findCirclesGrid (img, calib->boardSize, pointBuf);
break;
case GST_CAMERA_CALIBRATION_PATTERN_ASYMMETRIC_CIRCLES_GRID:
found =
cv::findCirclesGrid (img, calib->boardSize, pointBuf,
cv::CALIB_CB_ASYMMETRIC_GRID);
break;
default:
found = FALSE;
break;
}
bool blinkOutput = FALSE;
if (found) {
/* improve the found corners' coordinate accuracy for chessboard */
if (calib->calibrationPattern == GST_CAMERA_CALIBRATION_PATTERN_CHESSBOARD
&& calib->cornerSubPix) {
/* FIXME findChessboardCorners and alike do a cv::COLOR_BGR2GRAY (and a histogram balance)
* the color convert should be done once (if needed) and shared
* FIXME keep viewGray around to avoid reallocating it each time... */
cv::Mat viewGray;
cv::cvtColor (img, viewGray, cv::COLOR_BGR2GRAY);
cv::cornerSubPix (viewGray, pointBuf, cv::Size (11, 11), cv::Size (-1,
-1),
cv::TermCriteria (cv::TermCriteria::EPS + cv::TermCriteria::COUNT,
30, 0.1));
}
/* take new samples after delay time */
if ((calib->mode == CAPTURING)
&& ((clock () - calib->prevTimestamp) >
calib->delay * 1e-3 * CLOCKS_PER_SEC)) {
calib->imagePoints.push_back (pointBuf);
calib->prevTimestamp = clock ();
blinkOutput = true;
}
/* draw the corners */
if (calib->showCorners) {
cv::drawChessboardCorners (img, calib->boardSize, cv::Mat (pointBuf),
found);
}
}
/* if got enough frames then stop calibration and show result */
if (calib->mode == CAPTURING
&& calib->imagePoints.size () >= (size_t) calib->nrFrames) {
if (camera_calibrate_calibrate (calib, imageSize, calib->cameraMatrix,
calib->distCoeffs, calib->imagePoints)) {
calib->mode = CALIBRATED;
GstPad *sink_pad = GST_BASE_TRANSFORM_SINK_PAD (calib);
GstPad *src_pad = GST_BASE_TRANSFORM_SRC_PAD (calib);
GstEvent *sink_event;
GstEvent *src_event;
/* set settings property */
g_free (calib->settings);
calib->settings =
camera_serialize_undistort_settings (calib->cameraMatrix,
calib->distCoeffs);
/* create calibrated event and send upstream and downstream */
sink_event = gst_camera_event_new_calibrated (calib->settings);
GST_LOG_OBJECT (sink_pad, "Sending upstream event %s.",
GST_EVENT_TYPE_NAME (sink_event));
if (!gst_pad_push_event (sink_pad, sink_event)) {
GST_WARNING_OBJECT (sink_pad,
"Sending upstream event %p (%s) failed.", sink_event,
GST_EVENT_TYPE_NAME (sink_event));
}
src_event = gst_camera_event_new_calibrated (calib->settings);
GST_LOG_OBJECT (src_pad, "Sending downstream event %s.",
GST_EVENT_TYPE_NAME (src_event));
if (!gst_pad_push_event (src_pad, src_event)) {
GST_WARNING_OBJECT (src_pad,
"Sending downstream event %p (%s) failed.", src_event,
GST_EVENT_TYPE_NAME (src_event));
}
} else {
/* failed to calibrate, go back to detection mode */
calib->mode = DETECTION;
}
}
if (calib->mode == CAPTURING && blinkOutput) {
bitwise_not (img, img);
}
}
/* output text */
/* FIXME ll additional rendering (text, corners, ...) should be done with
* cairo or another gst framework.
* this will relax the conditions on the input format (RBG only at the moment).
* the calibration itself accepts more formats... */
std::string msg = (calib->mode == CAPTURING) ? "100/100" :
(calib->mode == CALIBRATED) ? "Calibrated" : "Waiting...";
int baseLine = 0;
cv::Size textSize = cv::getTextSize (msg, 1, 1, 1, &baseLine);
cv::Point textOrigin (img.cols - 2 * textSize.width - 10,
img.rows - 2 * baseLine - 10);
if (calib->mode == CAPTURING) {
msg =
cv::format ("%d/%d", (int) calib->imagePoints.size (), calib->nrFrames);
}
const cv::Scalar RED (0, 0, 255);
const cv::Scalar GREEN (0, 255, 0);
cv::putText (img, msg, textOrigin, 1, 1,
calib->mode == CALIBRATED ? GREEN : RED);
}
static double
camera_calibrate_calc_reprojection_errors (const std::vector < std::vector <
cv::Point3f > >&objectPoints,
const std::vector < std::vector < cv::Point2f > >&imagePoints,
const std::vector < cv::Mat > &rvecs, const std::vector < cv::Mat > &tvecs,
const cv::Mat & cameraMatrix, const cv::Mat & distCoeffs,
std::vector < float >&perViewErrors, bool fisheye)
{
std::vector < cv::Point2f > imagePoints2;
size_t totalPoints = 0;
double totalErr = 0, err;
perViewErrors.resize (objectPoints.size ());
for (size_t i = 0; i < objectPoints.size (); ++i) {
if (fisheye) {
cv::fisheye::projectPoints (objectPoints[i], imagePoints2,
rvecs[i], tvecs[i], cameraMatrix, distCoeffs);
} else {
cv::projectPoints (objectPoints[i], rvecs[i], tvecs[i],
cameraMatrix, distCoeffs, imagePoints2);
}
err = cv::norm (imagePoints[i], imagePoints2, cv::NORM_L2);
size_t n = objectPoints[i].size ();
perViewErrors[i] = (float) std::sqrt (err * err / n);
totalErr += err * err;
totalPoints += n;
}
return std::sqrt (totalErr / totalPoints);
}
static void
camera_calibrate_calc_corners (cv::Size boardSize, float squareSize,
std::vector < cv::Point3f > &corners, gint patternType /*= CHESSBOARD*/ )
{
corners.clear ();
switch (patternType) {
case GST_CAMERA_CALIBRATION_PATTERN_CHESSBOARD:
case GST_CAMERA_CALIBRATION_PATTERN_CIRCLES_GRID:
for (int i = 0; i < boardSize.height; ++i)
for (int j = 0; j < boardSize.width; ++j)
corners.push_back (cv::Point3f (j * squareSize, i * squareSize, 0));
break;
case GST_CAMERA_CALIBRATION_PATTERN_ASYMMETRIC_CIRCLES_GRID:
for (int i = 0; i < boardSize.height; i++)
for (int j = 0; j < boardSize.width; j++)
corners.push_back (cv::Point3f ((2 * j + i % 2) * squareSize,
i * squareSize, 0));
break;
default:
break;
}
}
static bool
camera_calibrate_calibrate_full (GstCameraCalibrate * calib,
cv::Size & imageSize, cv::Mat & cameraMatrix, cv::Mat & distCoeffs,
std::vector < std::vector < cv::Point2f > >imagePoints,
std::vector < cv::Mat > &rvecs, std::vector < cv::Mat > &tvecs,
std::vector < float >&reprojErrs, double &totalAvgErr)
{
cameraMatrix = cv::Mat::eye (3, 3, CV_64F);
if (calib->flags & cv::CALIB_FIX_ASPECT_RATIO) {
cameraMatrix.at < double >(0, 0) = calib->aspectRatio;
}
if (calib->useFisheye) {
distCoeffs = cv::Mat::zeros (4, 1, CV_64F);
} else {
distCoeffs = cv::Mat::zeros (8, 1, CV_64F);
}
std::vector < std::vector < cv::Point3f > >objectPoints (1);
camera_calibrate_calc_corners (calib->boardSize, calib->squareSize,
objectPoints[0], calib->calibrationPattern);
objectPoints.resize (imagePoints.size (), objectPoints[0]);
/* Find intrinsic and extrinsic camera parameters */
double rms;
if (calib->useFisheye) {
cv::Mat _rvecs, _tvecs;
rms = cv::fisheye::calibrate (objectPoints, imagePoints, imageSize,
cameraMatrix, distCoeffs, _rvecs, _tvecs, calib->flags);
rvecs.reserve (_rvecs.rows);
tvecs.reserve (_tvecs.rows);
for (int i = 0; i < int (objectPoints.size ()); i++) {
rvecs.push_back (_rvecs.row (i));
tvecs.push_back (_tvecs.row (i));
}
} else {
rms = cv::calibrateCamera (objectPoints, imagePoints, imageSize,
cameraMatrix, distCoeffs, rvecs, tvecs, calib->flags);
}
GST_LOG_OBJECT (calib,
"Re-projection error reported by calibrateCamera: %f", rms);
bool ok = checkRange (cameraMatrix) && checkRange (distCoeffs);
totalAvgErr =
camera_calibrate_calc_reprojection_errors (objectPoints, imagePoints,
rvecs, tvecs, cameraMatrix, distCoeffs, reprojErrs, calib->useFisheye);
return ok;
}
bool
camera_calibrate_calibrate (GstCameraCalibrate * calib,
cv::Size imageSize, cv::Mat & cameraMatrix, cv::Mat & distCoeffs,
std::vector < std::vector < cv::Point2f > >imagePoints)
{
std::vector < cv::Mat > rvecs, tvecs;
std::vector < float >reprojErrs;
double totalAvgErr = 0;
bool ok = camera_calibrate_calibrate_full (calib,
imageSize, cameraMatrix, distCoeffs, imagePoints,
rvecs, tvecs, reprojErrs, totalAvgErr);
GST_LOG_OBJECT (calib, (ok ? "Calibration succeeded" : "Calibration failed"));
/* + ". avg re projection error = " + totalAvgErr); */
return ok;
}
/* entry point to initialize the plug-in
* initialize the plug-in itself
* register the element factories and other features
*/
gboolean
gst_camera_calibrate_plugin_init (GstPlugin * plugin)
{
/* debug category for filtering log messages */
GST_DEBUG_CATEGORY_INIT (gst_camera_calibrate_debug, "cameracalibrate",
0, "Performs camera calibration");
return gst_element_register (plugin, "cameracalibrate", GST_RANK_NONE,
GST_TYPE_CAMERA_CALIBRATE);
}