- Add support for refining the camera's intrinsic parameters
during a solve. Currently, refining supports only the following
combinations of intrinsic parameters:
f
f, cx, cy
f, cx, cy, k1, k2
f, k1
f, k1, k2
This is not the same as autocalibration, since the user must
still make a reasonable initial guess about the focal length and
other parameters, whereas true autocalibration would eliminate
the need for the user specify intrinsic parameters at all.
However, the solver works well with only rough guesses for the
focal length, so perhaps full autocalibation is not that
important.
Adding support for the last two combinations, (f, k1) and (f,
k1, k2) required changes to the library libmv depends on for
bundle adjustment, SSBA. These changes should get ported
upstream not just to libmv but to SSBA as well.
- Improved the region of convergence for bundle adjustment by
increasing the number of Levenberg-Marquardt iterations from 50
to 500. This way, the solver is able to crawl out of the bad
local minima it gets stuck in when changing from, for example,
bundling k1 and k2 to just k1 and resetting k2 to 0.
- Add several new region tracker implementations. A region tracker
is a libmv concept, which refers to tracking a template image
pattern through frames. The impact to end users is that tracking
should "just work better". I am reserving a more detailed
writeup, and maybe a paper, for later.
- Other libmv tweaks, such as detecting that a tracker is headed
outside of the image bounds.
This includes several changes made directly to the libmv extern
code rather expecting to get those changes through normal libmv
channels, because I, the libmv BDFL, decided it was faster to work
on libmv directly in Blender, then later reverse-port the libmv
changes from Blender back into libmv trunk. The interesting part
is that I added a full Levenberg-Marquardt loop to the region
tracking code, which should lead to a more stable solutions. I
also added a hacky implementation of "Efficient Second-Order
Minimization" for tracking, which works nicely. A more detailed
quantitative evaluation will follow.
===========================
- Bundle re-newed libmv library.
- Update API in libmv-capi to match new library.
- Initial implementaition of feature detection.
- Fixed bug with incorrect user sync when tracking
for first frame.
===========================
- 32 bit linux compilation should be fixed now.
- Camrea reconstruction data should be better now
when there's no reconstructed cameras.
- Implemented "Set Origin" operator
- Added "Specials" W-key menu for SpaceClip.
Supports such operators:
* Enable track
* Disable track
* Set origin
===========================
- ColaMD moved from OpenNL to extern/.
It'll be needed for libmv. Also, it's a bit updated from
year 1999 to 2007.
Need to be tested for regressions.
- Updated bundling script for libmv. Now it uses fuller
subset of this library.
- Bundled new libmv.
- Request from Keir: add command line argument to toggle logging
stuff on. Currently, if Blender is launched with -d argument
libmv would start printing logging messages. There's no
argument to increase verbosity, but there's API in libmv-capi,
so it'll be easy to add.
- Finally fixed crash when ibuf is acquiring with user=NULL.
- Added ActiveClip property to the scene. This clip is used
as default value for new match-moving constraints.
- Added some flags to Display panel of View3D. Related on
displaying match-moving stuff.
- Internal change: bundles data moved inside to MovieTrackingTrack.
- Initial implementation of 3d reconstruction.
- Added constraint "Camera Solver". This constraint is supposed
to be used to make camera follow the reconstructed camera path.
- Added "reference" property to "Follow Track" constraint.
Now object could be "parented" to 2D track position or to
3D bundle position.
The very quick guide:
To use reconstruction you should have footage with tracked markers,
choose two keyframes in "Tracking settings" panel. There should be
quite noticeable parallax effect between this two frames. This
is used to initialize reconstruction stuff.
Camera data (focal length and optical center) should be filled in
"Camera Data" panel. Optical center is often the center of image,
so it'll be filled in automatically.
You should also set values for undistortion (K1, K2 and K3). Currently,
there's no any visualization for this parameters and approach of
"change value -> reconstruct -> see what've changed" is the only way
for now.
Libmv team is working on auto-calibration tool, so it should be
easier to gather this coefficients in nearest (i hope) future.
There's also no scene orientation stuff.
Basic workflow:
- Open footage.
- Set markers and track them.
- Fill in camera data and keyframes.
- Hit "Solve Camera" button.
- Add "Camera Solver" constraint to camera in scene.
- Choose movieclip in that constraint.
- To see bundles in 3D viewport active clip should be set
in scene buttons.
