mirror of
https://github.com/opencv/opencv.git
synced 2024-12-15 18:09:11 +08:00
106 lines
3.7 KiB
Markdown
106 lines
3.7 KiB
Markdown
High level stitching API (Stitcher class) {#tutorial_stitcher}
|
|
=========================================
|
|
|
|
Goal
|
|
----
|
|
|
|
In this tutorial you will learn how to:
|
|
|
|
- use the high-level stitching API for stitching provided by
|
|
- @ref cv::Stitcher
|
|
- learn how to use preconfigured Stitcher configurations to stitch images
|
|
using different camera models.
|
|
|
|
Code
|
|
----
|
|
|
|
This tutorial code's is shown lines below. You can also download it from
|
|
[here](https://github.com/opencv/opencv/tree/3.4/samples/cpp/samples/cpp/stitching.cpp).
|
|
|
|
@include samples/cpp/stitching.cpp
|
|
|
|
Explanation
|
|
-----------
|
|
|
|
The most important code part is:
|
|
|
|
@snippet cpp/stitching.cpp stitching
|
|
|
|
A new instance of stitcher is created and the @ref cv::Stitcher::stitch will
|
|
do all the hard work.
|
|
|
|
@ref cv::Stitcher::create can create stitcher in one of the predefined
|
|
configurations (argument `mode`). See @ref cv::Stitcher::Mode for details. These
|
|
configurations will setup multiple stitcher properties to operate in one of
|
|
predefined scenarios. After you create stitcher in one of predefined
|
|
configurations you can adjust stitching by setting any of the stitcher
|
|
properties.
|
|
|
|
If you have cuda device @ref cv::Stitcher can be configured to offload certain
|
|
operations to GPU. If you prefer this configuration set `try_use_gpu` to true.
|
|
OpenCL acceleration will be used transparently based on global OpenCV settings
|
|
regardless of this flag.
|
|
|
|
Stitching might fail for several reasons, you should always check if
|
|
everything went good and resulting pano is stored in `pano`. See
|
|
@ref cv::Stitcher::Status documentation for possible error codes.
|
|
|
|
Camera models
|
|
-------------
|
|
|
|
There are currently 2 camera models implemented in stitching pipeline.
|
|
|
|
- _Homography model_ expecting perspective transformations between images
|
|
implemented in @ref cv::detail::BestOf2NearestMatcher cv::detail::HomographyBasedEstimator
|
|
cv::detail::BundleAdjusterReproj cv::detail::BundleAdjusterRay
|
|
- _Affine model_ expecting affine transformation with 6 DOF or 4 DOF implemented in
|
|
@ref cv::detail::AffineBestOf2NearestMatcher cv::detail::AffineBasedEstimator
|
|
cv::detail::BundleAdjusterAffine cv::detail::BundleAdjusterAffinePartial cv::AffineWarper
|
|
|
|
Homography model is useful for creating photo panoramas captured by camera,
|
|
while affine-based model can be used to stitch scans and object captured by
|
|
specialized devices.
|
|
|
|
@note
|
|
Certain detailed settings of @ref cv::Stitcher might not make sense. Especially
|
|
you should not mix classes implementing affine model and classes implementing
|
|
Homography model, as they work with different transformations.
|
|
|
|
Try it out
|
|
----------
|
|
|
|
If you enabled building samples you can found binary under
|
|
`build/bin/cpp-example-stitching`. This example is a console application, run it without
|
|
arguments to see help. `opencv_extra` provides some sample data for testing all available
|
|
configurations.
|
|
|
|
to try panorama mode run:
|
|
```
|
|
./cpp-example-stitching --mode panorama <path to opencv_extra>/testdata/stitching/boat*
|
|
```
|
|
![](images/boat.jpg)
|
|
|
|
to try scans mode run (dataset from home-grade scanner):
|
|
```
|
|
./cpp-example-stitching --mode scans <path to opencv_extra>/testdata/stitching/newspaper*
|
|
```
|
|
![](images/newspaper.jpg)
|
|
|
|
or (dataset from professional book scanner):
|
|
```
|
|
./cpp-example-stitching --mode scans <path to opencv_extra>/testdata/stitching/budapest*
|
|
```
|
|
![](images/budapest.jpg)
|
|
|
|
@note
|
|
Examples above expects POSIX platform, on windows you have to provide all files names explicitly
|
|
(e.g. `boat1.jpg` `boat2.jpg`...) as windows command line does not support `*` expansion.
|
|
|
|
See also
|
|
--------
|
|
|
|
If you want to study internals of the stitching pipeline or you want to experiment with detailed
|
|
configuration see
|
|
[stitching_detailed.cpp](https://github.com/opencv/opencv/tree/3.4/samples/cpp/stitching_detailed.cpp)
|
|
in `opencv/samples/cpp` folder.
|