As far as i remember Keir, this should be safe for our usages of ceres
and it should save noticeable amount of time and used memory when
compiling blender with libmv support.
Quick tests with tracking went smooth after this.
Added option to use Grease Pencil datablock as a mask for pattern
when doing motion tracking. Option could be found in Tracking Settings
panel.
All strokes would be rasterized separately from each other and every
stroke is treating as a closed spline.
Also added option to apply a mask on track preview which is situated
just after B/B/W channel button under track preview.
Helps keeping features tracked when there's large scale happens
without need to manually re-adjust search area.
Currently using factor of pattern's boundbox scale, but probably
could be done in more accurate way?
This patch aims to solve unaligned operation assert
happens in Eigen library.
This is short-term solution which in fact shall be reverted
as soon as real solution would be added to Ceres. Meanwhile
this should be acceptable to have for a while.
===========================================
Major list of changes done in tomato branch:
- Add a planar tracking implementation to libmv
This adds a new planar tracking implementation to libmv. The
tracker is based on Ceres[1], the new nonlinear minimizer that
myself and Sameer released from Google as open source. Since
the motion model is more involved, the interface is
different than the RegionTracker interface used previously
in Blender.
The start of a C API in libmv-capi.{cpp,h} is also included.
- Migrate from pat_{min,max} for markers to 4 corners representation
Convert markers in the movie clip editor / 2D tracker from using
pat_min and pat_max notation to using the a more general, 4-corner
representation.
There is still considerable porting work to do; in particular
sliding from preview widget does not work correct for rotated
markers.
All other areas should be ported to new representation:
* Added support of sliding individual corners. LMB slide + Ctrl
would scale the whole pattern
* S would scale the whole marker, S-S would scale pattern only
* Added support of marker's rotation which is currently rotates
only patterns around their centers or all markers around median,
Rotation or other non-translation/scaling transformation of search
area doesn't make sense.
* Track Preview widget would display transformed pattern which
libmv actually operates with.
- "Efficient Second-order Minimization" for the planar tracker
This implements the "Efficient Second-order Minimization"
scheme, as supported by the existing translation tracker.
This increases the amount of per-iteration work, but
decreases the number of iterations required to converge and
also increases the size of the basin of attraction for the
optimization.
- Remove the use of the legacy RegionTracker API from Blender,
and replaces it with the new TrackRegion API. This also
adds several features to the planar tracker in libmv:
* Do a brute-force initialization of tracking similar to "Hybrid"
mode in the stable release, but using all floats. This is slower
but more accurate. It is still necessary to evaluate if the
performance loss is worth it. In particular, this change is
necessary to support high bit depth imagery.
* Add support for masks over the search window. This is a step
towards supporting user-defined tracker masks. The tracker masks
will make it easy for users to make a mask for e.g. a ball.
Not exposed into interface yet/
* Add Pearson product moment correlation coefficient checking (aka
"Correlation" in the UI. This causes tracking failure if the
tracked patch is not linearly related to the template.
* Add support for warping a few points in addition to the supplied
points. This is useful because the tracking code deliberately
does not expose the underlying warp representation. Instead,
warps are specified in an aparametric way via the correspondences.
- Replace the old style tracker configuration panel with the
new planar tracking panel. From a users perspective, this means:
* The old "tracking algorithm" picker is gone. There is only 1
algorithm now. We may revisit this later, but I would much
prefer to have only 1 algorithm. So far no optimization work
has been done so the speed is not there yet.
* There is now a dropdown to select the motion model. Choices:
* Translation
* Translation, rotation
* Translation, scale
* Translation, rotation, scale
* Affine
* Perspective
* The old "Hybrid" mode is gone; instead there is a toggle to
enable or disable translation-only tracker initialization. This
is the equivalent of the hyrbid mode before, but rewritten to work
with the new planar tracking modes.
* The pyramid levels setting is gone. At a future date, the planar
tracker will decide to use pyramids or not automatically. The
pyramid setting was ultimately a mistake; with the brute force
initialization it is unnecessary.
- Add light-normalized tracking
Added the ability to normalize patterns by their average value while
tracking, to make them invariant to global illumination changes.
Additional details could be found at wiki page [2]
[1] http://code.google.com/p/ceres-solver
[2] http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.64/Motion_Tracker
Currently only put sources of Ceres library into extern/libmv/third_party and
setup CMake and SCons building systems.
Integration details:
- Even CMake build files are not re-used from Ceres's trunk: they're using some
automatic stuff detection like glog, pthreads, protobuf and so and it's not
so clear how to re-use that files without modifications.
And IMO it's easier if build files are getting re-generated automatically to
match Blender-specific setup rather than keeping changes made locally in
Blender in sync when re-bundling Ceres library. Especially in case when it's
already needed to support SCons build system.
- Integrated only actual sources, all tests were stripped. Probably it'll be nice
to have them, but they'll need clear integration with current module test stuff
in Blender.
- Suitesparse was disabled. It'll help a lot having it, but there are some difficulties
making cholmod working fine on windows. Would be added in future
- collections_port.cc was also stripped. It's not used by Ceres's upstream and
it gives compilation error (undefined uint32 -- looks like namespace issue).
- Currently all schur eliminators are included. Not sure if it makes sense,
also not sure if it makes sense having them switchable on and off -- IMO better
to have single configuration which works and does not require special tweaks
after everything was set up.
To bundle updated version of Ceres:
- Go to extern/libmv/third_party/ceres folder
- Run ./bundle.sh
This will checkout fresh Ceres snapshot of Windows branch (which is currently
most interesting from integration into Blender POV), apply all patches listed
in patches/series and copy needed files into Blender's working copy. This will
also re-generate CMake/SCons build rules.
If you'll need extra files from Ceres repository which are not present in
Blender, you'll need to copy them manually and then run ./mkfiles.sh from
extern/libmv/third_party/ceres folder which will update list of files used
by Blender.
Thanks to Leir Mierle and Sameer Agarwal (and all others who helped developing
Ceres) this library and thanks to Keir Mierle with help integrating it into Blender!
Expose option into interface to use modal solver which currently
supports only tripod motion.
This solver requires two tracks at least to reconstruct motion.
Using more tracks aren't improving solution in general, just adds
instability into solution and slows down things a lot.
Refirement of camera intrinsics was disabled due to it's not only
refines camera intrinsics but also adjusts camera position which
isn't necessary here
To use this solver just activate "Tripod Motion" checkbox in
solver panel.
Merged from tomato: svn merge ^/branches/soc-2011-tomato -r45622:45624 -r46036:46037
P.S. Quite experimental yet, requires more checking and probably
tweaks to prevent camera jumps when tracks apperars/disappears
from the screen.
Expose option into interface to use modal solver which currently
supports only tripod motion.
This solver requires two tracks at least to reconstruct motion.
Using more tracks aren't improving solution in general, just adds
instability into solution and slows down things a lot.
Refirement of camera intrinsics is supported by this solver.
To use this solver just activate "Tripod Motion" checkbox in
solver panel.
- Deduplicate patetrn sampling used in esm and lmicklt trackers and
move SamplePattern to image/sample.h - Move computation of Pearson
product-moment correlation into own function in new file image/correlation.h
so all trackers can use it to check final correlation.
- Remove SAD tracker. It's almost the same as brute tracker, with only two differences:
1. It does brute search of affine transformation which in some cases helps to track
rotating features 2. It didn't use common tracker api which probably gave some
speed advantage, but lead to a real headache to use it together with other
trackers leading to duplicated code in blender side.
- Switch blenedr to use brute tracker instead of sad tracker which tracking made
source code much more simple to follow.
Should resolve compilation error on some platforms when using linux and
compilation error of libmv on FreeBSB.
It was a regression caused by not applied changes on config_linux.h
and some changes made to utilities.cc were also occasionally missed.
This version of libmv includes new gflags and glog libraries which makes
it possible to compile libmv with clang compiler.
Also remove code from CMakeLists which was disabling libmv if using clang.
Tested on linux with gcc-4.6 and clang-3.0, windows cmake+msvc and scons+mingw.
Could be some issues with other platforms/build system which shall be simple to resolve.
Needed to make constants like M_E defined in msvc. Was occasionally
removed on moving main changes in libmv from patch files in blender
repo to won repo (rev44190).
