Skip to content

Fix importer intrinsics #518

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
simonfuhrmann merged 1 commit into from
Sep 9, 2020
Merged

Fix importer intrinsics #518

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
8 changes: 6 additions & 2 deletions apps/makescene/makescene.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -422,8 +422,12 @@ import_bundle_nvm_or_colmap (AppSettings const& conf, bool load_nvm = true)
add_exif_to_view(view, exif);

/* Normalize focal length, add undistorted image. */
int const maxdim = std::max(image->width(), image->height());
mve_cam.flen = mve_cam.flen / static_cast<float>(maxdim);
if (load_nvm)
{
// In the case of Colmap, the focal length is already normalized
int const maxdim = std::max(image->width(), image->height());
mve_cam.flen = mve_cam.flen / static_cast<float>(maxdim);
}

mve::ByteImage::Ptr undist;
if (load_nvm)
Expand Down
58 changes: 15 additions & 43 deletions libs/mve/bundle_io.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -23,6 +23,7 @@
#include "math/vector.h"
#include "mve/bundle_io.h"
#include "mve/image_tools.h"
#include "mve/depthmap.h"


MVE_NAMESPACE_BEGIN
Expand Down Expand Up @@ -549,8 +550,15 @@ create_camera_info_from_params(CameraInfo& camera_info,
// Pinhole: fx, fy, cx, cy
float fx = params[0];
float fy = params[1];
camera_info.flen = fx;
camera_info.paspect = fy / fx;
float dim_aspect = static_cast<float>(width) / height;
float pixel_aspect = fy / fx;
float img_aspect = dim_aspect * pixel_aspect;
if (img_aspect < 1.0f) {
camera_info.flen = fy / height;
} else {
camera_info.flen = fx / width;
}
camera_info.paspect = pixel_aspect;
camera_info.ppoint[0] = params[2] / width;
camera_info.ppoint[1] = params[3] / height;
}
Expand Down Expand Up @@ -1130,45 +1138,6 @@ parse_colmap_depth_map(const std::string& path)
return depth_img;
}

void
convert_depth_map_semantics(mve::CameraInfo& mve_cam, int original_width,
int original_height, mve::FloatImage::Ptr depth_image)
{
// The meaning of the depth map values in MVE and Colmap differs.
// In MVE the depth value is defined w.r.t. unit vectors.
// In Colmap the depth value is defined w.r.t. canonical vectors (i.e.
// the z-component is equal to 1).
size_t max_extent = std::max(original_width, original_height);
float fx = mve_cam.flen * max_extent;
float fy = fx * mve_cam.paspect;
float cx = mve_cam.ppoint[0] * original_width;
float cy = mve_cam.ppoint[1] * original_height;

size_t depth_map_width = depth_image->width();
size_t depth_map_height = depth_image->height();

float u_step_size = original_width / depth_map_width;
float v_step_size = original_height / depth_map_height;

for (int idx = 0; idx < depth_image->get_pixel_amount(); ++idx)
{
size_t u = idx % depth_map_width;
size_t v = idx / depth_map_width;
// No offset of 0.5 here, since Colmap depth values are defined w.r.t.
// shifted pixel values
float u_img = u_step_size * (float)u;
float v_img = v_step_size * (float)v;
// The cannoncial vectors are defined according to p.155 of
// "Multiple View Geometry" by Hartley and Zisserman
math::Vec3f canonical_ray{
(u_img - cx) / fx,
(v_img - cy) / fy,
1.0};
float norm = canonical_ray.norm();
depth_image->at(idx) = depth_image->at(idx) * norm;
}
}

mve::FloatImage::Ptr
load_colmap_depth_map(int scale, mve::CameraInfo& mve_cam, int original_width,
int original_height,
Expand All @@ -1182,8 +1151,11 @@ load_colmap_depth_map(int scale, mve::CameraInfo& mve_cam, int original_width,
int depth_width = depth_image->width();
int depth_height = depth_image->height();

convert_depth_map_semantics(mve_cam, original_width, original_height,
depth_image);
math::Matrix3f inv_calib;
mve_cam.fill_inverse_calibration(*inv_calib, original_width,
original_height);
mve::image::depthmap_convert_conventions<float>(depth_image, inv_calib,
true);

if (depth_width == original_width && depth_height == original_height)
{
Expand Down