This change solves a bottleneck which was caused by attempt to cache
postprocessed search areas used for tracking. It was a single cache
used by all threads, which required to have some synchronization
mechanism. This synchronization turned out to be making all threads
to idle while one thread is accessing the cache. The access was not
cheap, so the multi-threading did not provide expected speedup.
Current solution is to remove the cache of search areas. This avoids
any threading synchronization overhead because there is no need for
it anymore. The downside is that for certain configurations tracking
became slower when comparing to master branch. There is no expected
slowdown compared to 2.91 release.
The slowdown is mainly experienced when using big search area and
keyframe matching strategy. Other cases should still be within a
ballpark of performance of single-threaded code prior to this change.
The reason why is it so is because while this change makes it so the
image accessors needs to process images multiple times the complexity
of this process is almost the same as all the overhead for the cache
lookup and maintenance.
Here are Some numbers gained on different configurations.
CPU: Intel Xeom CPU E5-2699 v4
OS: Linux
Footage: Old_Factory MVI_4005.mov from the first part of Track Match
Blend training which can be found on the Blender Cloud.
Tracking 443 markers across 250 frames. The unit is seconds.
File: F9433209
2.91: 401.520874
before: 358.650055
after: 14.966302
Tracking single marker across 250 frames. The unit is seconds.
File: F9433211
2.91 before after
Big keyframe 1.307203 1.005324 1.227300
Big previous frame 1.144055 0.881139 0.944044
Small keyframe 0.434015 0.197760 0.224982
Small previous frame 0.463207 0.218058 0.234172
All at once 2.338268 1.481220 1.518060
Previously image accessor was sharing array pointer for tracks access.
Now it is possible to pass a temporary array valid only during the
initialization process.
Should be no functional changes.
Implemented Brown-Conrady lens distortion model with 4 radial and
2 tangential coefficients to improve compatibility with other software,
such as Agisoft Photoscan/Metashapes, 3DF Zephir, RealityCapture,
Bentley ContextCapture, Alisevision Meshroom(opensource).
Also older programs: Bundler, CPMVS.
In general terms, most photogrammetric software.
The new model is available under the distortion model menu in Lens
settings.
For tests and demos check the original patch.
Reviewed By: sergey
Differential Revision: https://developer.blender.org/D9037
Neither Nuke nor Natron support OpenCV's radial distortion model
which makes it impossible to have any kind of interoperability.
The new model is available under the distortion model menu in Lens
settings.
Differential Revision: https://developer.blender.org/D7484
Allows to open newer files in older Blender after new distortion model
has been added.
It will behave as if this is a polynomial model with all 0 coefficients
which are then being refined and assigned explicitly after solving the
motion.
Need to communicate available number of threads to the camera
intrinsics implementation, otherwise default value of 1 is used.
Must have been single-threaded for a very long time.
Mainly affects for() loops.
The reason why loop parameter was declared outside of the loop roots
back to the times when not all compilers supported C99.
BF-admins agree to remove header information that isn't useful,
to reduce noise.
- BEGIN/END license blocks
Developers should add non license comments as separate comment blocks.
No need for separator text.
- Contributors
This is often invalid, outdated or misleading
especially when splitting files.
It's more useful to git-blame to find out who has developed the code.
See P901 for script to perform these edits.
- Use BLI_threadpool_ prefix for (deprecated)
thread/listbase API.
- Use BLI_thread as prefix for other functions.
See P614 to apply instead of manually resolving conflicts.
Enabled cache for frame accessor and tweaked policy so we guarantee keyframed
images to be always in the cache. The logic might fail in some real corner case
(for example, when doing multiple tracks at once on a system where we can not
fit 2 clip frames in cache) but things are much better now for regular use.
This feature got lost with new auto-track API,
Added it back by extending frame accessor class. This isn't really
a frame thing, but we don't have other type of accessor here.
Surely, we can use old-style API here and pass mask via region
tracker options for this particular case, but then it becomes much
less obvious how real auto-tracker will access this mask with old
style API.
So seems we do need an accessor for such data, just matter of
finding better place than frame accessor.
Things like `BLI_uniquename` had nothing, but really nothing to do in
BLI_path_util files!
Also, got rid of length limitation in `BLI_uniquename_cb`, we can use
alloca here to avoid overhead of malloc while keeping free size (within
reasonable limits of course).
- Add blentranslation `BLT_*` module.
- moved & split `BLF_translation.h` into (`BLT_translation.h`, `BLT_lang.h`).
- moved `BLF_*_unifont` functions from `blf_translation.c` to new source file `blf_font_i18n.c`.
This was never ported to a new tracking pipeline and now it's done using
FrameAccessor::Transform routines. Quite striaghtforward, but i've changed
order of grayscale conversion in blender side with call of transform callback.
This way it's much easier to perform rescaling in libmv side.
The title actually tells it all, this commit switches Blender to use the new
autotrack API from Libmv.
From the user point of view it means that prediction model is now used when
tracking which gives really nice results.
All the other changes are not really visible for users, those are just frame
accessors, caches and so for the new API.
This commit makes it so CameraIntrinsics is no longer hardcoded
to use the traditional polynomial radial distortion model. Currently
the distortion code has generic logic which is shared between
different distortion models, but had no other models until now.
This moves everything specific to the polynomial radial distortion
to a subclass PolynomialDistortionCameraIntrinsics(), and adds a
new division distortion model suitable for cameras such as the
GoPro which have much stronger distortion due to their fisheye lens.
This also cleans up the internal API of CameraIntrinsics to make
it easier to understand and reduces old C-style code.
New distortion model is available in the Lens panel of MCE.
- Polynomial is the old well-known model
- Division is the new one which s intended to deal better with huge
distortion.
Coefficients of this model works independent from each other
and for division model one probably want to have positive values
to have a barrel distortion.
File tracking.c became rather huge and annoying to
maintain and it really contains several independent
areas of motrack pipeline.
Now we've got:
* tracking.c: general-purpose functions which are used
by blender, clip editor, RNA and so.
* tracking_detect.c: feature detection functions
(blender-side, logic is still in libmv).
* tracking_plane_tracker.c: blender-side 2D tracking logic.
* tracking_plane_tracker.c: plane track tracker.
* tracking_solver.c: functions for camera solving.
* tracking_stabilize.c: 2D stabilization functions.
* tracking_util.c: utility functions for all those files
and which shouldn't be public.
