[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [54932] trunk/blender: Modal (aka tripod) solver rework
Sergey Sharybin
sergey.vfx at gmail.com
Thu Feb 28 15:24:42 CET 2013
Revision: 54932
http://projects.blender.org/scm/viewvc.php?view=rev&root=bf-blender&revision=54932
Author: nazgul
Date: 2013-02-28 14:24:42 +0000 (Thu, 28 Feb 2013)
Log Message:
-----------
Modal (aka tripod) solver rework
Several major things are done in this commit:
- First of all, logic of modal solver was changed.
We do not rely on only minimizer to take care of
guessing rotation for frame, but we're using
analytical rotation computation for point clouds
to obtain initial rotation.
Then this rotation is being refined using Ceres
minimizer and now instead of minimizing average
distance between points of point of two clouds,
minimization of reprojection error of point
cloud onto frame happens.
This gives quite a bit of precision improvement.
- Second bigger improvement here is using bundle
adjustment for a result of first step when we're
only estimating rotation between neighbor images
and reprojecting markers.
This averages error across the image sequence
avoiding error accumulation. Also, this will
tweak bundles themselves a bit for better match.
- And last bigger improvement here is support of
camera intrinsics refirenment.
This allowed to significantly improve solution
for real-life footage and results after such
refining are much more usable than it were before.
Thanks to Keir for the help and code review.
Modified Paths:
--------------
trunk/blender/extern/libmv/CMakeLists.txt
trunk/blender/extern/libmv/files.txt
trunk/blender/extern/libmv/libmv/simple_pipeline/bundle.cc
trunk/blender/extern/libmv/libmv/simple_pipeline/bundle.h
trunk/blender/extern/libmv/libmv/simple_pipeline/modal_solver.cc
trunk/blender/extern/libmv/libmv-capi.cpp
trunk/blender/extern/libmv/libmv-capi.h
trunk/blender/release/scripts/startup/bl_ui/space_clip.py
trunk/blender/source/blender/blenkernel/intern/tracking.c
Added Paths:
-----------
trunk/blender/extern/libmv/libmv/multiview/panography.h
Modified: trunk/blender/extern/libmv/CMakeLists.txt
===================================================================
--- trunk/blender/extern/libmv/CMakeLists.txt 2013-02-28 14:24:25 UTC (rev 54931)
+++ trunk/blender/extern/libmv/CMakeLists.txt 2013-02-28 14:24:42 UTC (rev 54932)
@@ -99,6 +99,7 @@
libmv/multiview/homography.h
libmv/multiview/homography_parameterization.h
libmv/multiview/nviewtriangulation.h
+ libmv/multiview/panography.h
libmv/multiview/projection.h
libmv/multiview/resection.h
libmv/multiview/triangulation.h
Modified: trunk/blender/extern/libmv/files.txt
===================================================================
--- trunk/blender/extern/libmv/files.txt 2013-02-28 14:24:25 UTC (rev 54931)
+++ trunk/blender/extern/libmv/files.txt 2013-02-28 14:24:42 UTC (rev 54932)
@@ -21,6 +21,7 @@
libmv/multiview/homography.h
libmv/multiview/homography_parameterization.h
libmv/multiview/nviewtriangulation.h
+libmv/multiview/panography.h
libmv/multiview/projection.cc
libmv/multiview/projection.h
libmv/multiview/resection.h
@@ -142,25 +143,6 @@
third_party/glog/src/windows/port.cc
third_party/glog/src/windows/port.h
third_party/glog/src/windows/preprocess.sh
-third_party/ldl/CMakeLists.txt
-third_party/ldl/Doc/ChangeLog
-third_party/ldl/Doc/lesser.txt
-third_party/ldl/Include/ldl.h
-third_party/ldl/README.libmv
-third_party/ldl/README.txt
-third_party/ldl/Source/ldl.c
third_party/msinttypes/inttypes.h
third_party/msinttypes/README.libmv
third_party/msinttypes/stdint.h
-third_party/ssba/COPYING.TXT
-third_party/ssba/Geometry/v3d_cameramatrix.h
-third_party/ssba/Geometry/v3d_distortion.h
-third_party/ssba/Geometry/v3d_metricbundle.cpp
-third_party/ssba/Geometry/v3d_metricbundle.h
-third_party/ssba/Math/v3d_linear.h
-third_party/ssba/Math/v3d_linear_utils.h
-third_party/ssba/Math/v3d_mathutilities.h
-third_party/ssba/Math/v3d_optimization.cpp
-third_party/ssba/Math/v3d_optimization.h
-third_party/ssba/README.libmv
-third_party/ssba/README.TXT
Added: trunk/blender/extern/libmv/libmv/multiview/panography.h
===================================================================
--- trunk/blender/extern/libmv/libmv/multiview/panography.h (rev 0)
+++ trunk/blender/extern/libmv/libmv/multiview/panography.h 2013-02-28 14:24:42 UTC (rev 54932)
@@ -0,0 +1,181 @@
+// Copyright (c) 2009 libmv authors.
+//
+// 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.
+//
+
+#ifndef LIBMV_MULTIVIEW_PANOGRAPHY_H
+#define LIBMV_MULTIVIEW_PANOGRAPHY_H
+
+#include "libmv/numeric/numeric.h"
+#include "libmv/numeric/poly.h"
+#include "libmv/base/vector.h"
+
+namespace libmv {
+
+static bool Build_Minimal2Point_PolynomialFactor(
+ const Mat & x1, const Mat & x2,
+ double * P) //P must be a double[4]
+{
+ assert(2 == x1.rows());
+ assert(2 == x1.cols());
+ assert(x1.rows() == x2.rows());
+ assert(x1.cols() == x2.cols());
+
+ // Setup the variable of the input problem:
+ Vec xx1 = (x1.col(0)).transpose();
+ Vec yx1 = (x1.col(1)).transpose();
+
+ double a12 = xx1.dot(yx1);
+ Vec xx2 = (x2.col(0)).transpose();
+ Vec yx2 = (x2.col(1)).transpose();
+ double b12 = xx2.dot(yx2);
+
+ double a1 = xx1.squaredNorm();
+ double a2 = yx1.squaredNorm();
+
+ double b1 = xx2.squaredNorm();
+ double b2 = yx2.squaredNorm();
+
+ // Build the 3rd degre polynomial in F^2.
+ //
+ // f^6 * p + f^4 * q + f^2* r + s = 0;
+ //
+ // Coefficients in ascending powers of alpha, i.e. P[N]*x^N.
+ // Run panography_coeffs.py to get the below coefficients.
+ P[0] = b1*b2*a12*a12-a1*a2*b12*b12;
+ P[1] = -2*a1*a2*b12+2*a12*b1*b2+b1*a12*a12+b2*a12*a12-a1*b12*b12-a2*b12*b12;
+ P[2] = b1*b2-a1*a2-2*a1*b12-2*a2*b12+2*a12*b1+2*a12*b2+a12*a12-b12*b12;
+ P[3] = b1+b2-2*b12-a1-a2+2*a12;
+
+ // If P[3] equal to 0 we get ill conditionned data
+ return (P[3] != 0.0);
+}
+
+// This implements a minimal solution (2 points) for panoramic stitching:
+//
+// http://www.cs.ubc.ca/~mbrown/minimal/minimal.html
+//
+// [1] M. Brown and R. Hartley and D. Nister. Minimal Solutions for Panoramic
+// Stitching. CVPR07.
+//
+// The 2-point algorithm solves for the rotation of the camera with a single
+// focal length (4 degrees of freedom).
+//
+// Compute from 1 to 3 possible focal lenght for 2 point correspondences.
+// Suppose that the cameras share the same optical center and focal lengths:
+//
+// Image 1 => H*x = x' => Image 2
+// x (u1j) x' (u2j)
+// a (u11) a' (u21)
+// b (u12) b' (u22)
+//
+// The return values are 1 to 3 possible values for the focal lengths such
+// that:
+//
+// [f 0 0]
+// K = [0 f 0]
+// [0 0 1]
+//
+static void F_FromCorrespondance_2points(const Mat &x1, const Mat &x2,
+ vector<double> *fs) {
+
+ // Build Polynomial factor to get squared focal value.
+ double P[4];
+ Build_Minimal2Point_PolynomialFactor(x1, x2, &P[0]);
+
+ // Solve it by using F = f^2 and a Cubic polynomial solver
+ //
+ // F^3 * p + F^2 * q + F^1 * r + s = 0
+ //
+ double roots[3];
+ int num_roots = SolveCubicPolynomial(P, roots);
+ for (int i = 0; i < num_roots; ++i) {
+ if (roots[i] > 0.0) {
+ fs->push_back(sqrt(roots[i]));
+ }
+ }
+}
+
+// Compute the 3x3 rotation matrix that fits two 3D point clouds in the least
+// square sense. The method is from:
+//
+// K. Arun,T. Huand and D. Blostein. Least-squares fitting of 2 3-D point
+// sets. IEEE Transactions on Pattern Analysis and Machine Intelligence,
+// 9:698-700, 1987.
+//
+// Given the calibration matrices K1, K2 solve for the rotation from
+// corresponding image rays.
+//
+// R = min || X2 - R * x1 ||.
+//
+// In case of panography, which is for a camera that shares the same camera
+// center,
+//
+// H = K2 * R * K1.inverse();
+//
+// For the full explanation, see Section 8, Solving for Rotation from [1].
+//
+// Parameters:
+//
+// x1 : Point cloud A (3D coords)
+// x2 : Point cloud B (3D coords)
+//
+// [f 0 0]
+// K1 = [0 f 0]
+// [0 0 1]
+//
+// K2 (the same form as K1, but may have different f)
+//
+// Returns: A rotation matrix that minimizes
+//
+// R = arg min || X2 - R * x1 ||
+//
+static void GetR_FixedCameraCenter(const Mat &x1, const Mat &x2,
+ const double focal,
+ Mat3 *R) {
+ assert(3 == x1.rows());
+ assert(2 <= x1.cols());
+ assert(x1.rows() == x2.rows());
+ assert(x1.cols() == x2.cols());
+
+ // Build simplified K matrix
+ Mat3 K( Mat3::Identity() * 1.0/focal );
+ K(2,2)= 1.0;
+
+ // Build the correlation matrix; equation (22) in [1].
+ Mat3 C = Mat3::Zero();
+ for(int i = 0; i < x1.cols(); ++i) {
+ Mat r1i = (K * x1.col(i)).normalized();
+ Mat r2i = (K * x2.col(i)).normalized();
+ C += r2i * r1i.transpose();
+ }
+
+ // Solve for rotation. Equations (24) and (25) in [1].
+ Eigen::JacobiSVD<Mat> svd(C, Eigen::ComputeThinU | Eigen::ComputeThinV);
+ Mat3 scale = Mat3::Identity();
+ scale(2,2) = ((svd.matrixU() * svd.matrixV().transpose()).determinant() > 0.0)
+ ? 1.0
+ : -1.0;
+
+ (*R) = svd.matrixU() * scale * svd.matrixV().transpose();
+}
+
+} // namespace libmv
+
+#endif // LIBMV_MULTIVIEW_PANOGRAPHY_H
Modified: trunk/blender/extern/libmv/libmv/simple_pipeline/bundle.cc
===================================================================
--- trunk/blender/extern/libmv/libmv/simple_pipeline/bundle.cc 2013-02-28 14:24:25 UTC (rev 54931)
+++ trunk/blender/extern/libmv/libmv/simple_pipeline/bundle.cc 2013-02-28 14:24:42 UTC (rev 54932)
@@ -233,7 +233,8 @@
void EuclideanBundleCommonIntrinsics(const Tracks &tracks,
int bundle_intrinsics,
EuclideanReconstruction *reconstruction,
- CameraIntrinsics *intrinsics) {
+ CameraIntrinsics *intrinsics,
+ int bundle_constraints) {
LG << "Original intrinsics: " << *intrinsics;
vector<Marker> markers = tracks.AllMarkers();
@@ -270,7 +271,7 @@
}
problem.AddResidualBlock(new ceres::AutoDiffCostFunction<
- OpenCVReprojectionError, 2, 8, 9 /* 3 */, 3, 3>(
+ OpenCVReprojectionError, 2, 8, 9, 3, 3>(
new OpenCVReprojectionError(
marker.x,
marker.y)),
@@ -284,6 +285,10 @@
problem.SetParameterization(&camera->R(0, 0),
&rotation_parameterization);
+ if (bundle_constraints & BUNDLE_NO_TRANSLATION) {
+ problem.SetParameterBlockConstant(&camera->t(0));
+ }
+
num_residuals++;
}
LG << "Number of residuals: " << num_residuals;
Modified: trunk/blender/extern/libmv/libmv/simple_pipeline/bundle.h
===================================================================
--- trunk/blender/extern/libmv/libmv/simple_pipeline/bundle.h 2013-02-28 14:24:25 UTC (rev 54931)
+++ trunk/blender/extern/libmv/libmv/simple_pipeline/bundle.h 2013-02-28 14:24:42 UTC (rev 54932)
@@ -67,7 +67,12 @@
BUNDLE_FOCAL_LENGTH | BUNDLE_PRINCIPAL_POINT
BUNDLE_FOCAL_LENGTH | BUNDLE_PRINCIPAL_POINT | BUNDLE_RADIAL
BUNDLE_FOCAL_LENGTH | BUNDLE_PRINCIPAL_POINT | BUNDLE_RADIAL | BUNDLE_TANGENTIAL
+ BUNDLE_RADIAL
@@ Diff output truncated at 10240 characters. @@
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