imgcodecs: Add rgb flag for imread and imdecode #25809
Try to `imread` images by RGB to save R-B swapping costs.
## How to use it?
```
img_rgb = cv2.imread("PATH", IMREAD_COLOR_RGB) # OpenCV decode the image by RGB format.
```
## TODO
- [x] Fix the broken code
- [x] Add imread rgb test
- [x] Speed test of rgb mode.
## Performance test
| file name | IMREAD_COLOR | IMREAD_COLOR_RGB |
| --------- | ------ | --------- |
| jpg01 | 284 ms | 277 ms |
| jpg02 | 376 ms | 366 ms |
| png01 | 62 ms | 60 ms |
| Png02 | 97 ms | 94 ms |
Test with [image_test.zip](https://github.com/user-attachments/files/15982949/image_test.zip)
```.cpp
string img_path = "/Users/mzh/work/data/image_test/png02.png";
int loop = 20;
TickMeter t;
double t0 = 10000;
for (int i = 0; i < loop; i++)
{
t.reset();
t.start();
img_bgr = imread(img_path, IMREAD_COLOR);
t.stop();
if (t.getTimeMilli() < t0) t0 = t.getTimeMilli();
}
std::cout<<"bgr time = "<<t0<<std::endl;
t0 = 10000;
for (int i = 0; i < loop; i++)
{
t.reset();
t.start();
img_rgb = imread(img_path, IMREAD_COLOR_RGB);
t.stop();
if (t.getTimeMilli() < t0) t0 = t.getTimeMilli();
}
std::cout<<"rgb time = "<<t0<<std::endl;
```
### Pull Request Readiness Checklist
See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request
- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch
- [ ] There is a reference to the original bug report and related work
- [ ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
Patch to opencv_extra has the same branch name.
- [ ] The feature is well documented and sample code can be built with the project CMake
OpenEXR encoder: add capability to set the DWA compression level
* OpenEXR encoder: add capability to set the DWA compression level from outside
* Do not try to call `header.dwaCompressionLevel()` if OpenEXR is not version 3 or later
* Minor cleanup
Support building with OpenEXR 3.x
* Support OpenEXR 3.0
Try to find OpenEXR 3.0 using the upstream cmake config, and fallback to the previous algorithm if not found
* Add explicit ImfFrameBuffer.h include
This was transitively included with OpenEXR 2.x, but that's no longer the case with OpenEXR 3.x
OpenEXR compression options
* Adding possibility to select the compression type for the OpenEXR format.
There are compression modes other than the default that are more suited for certain data. Mainly grainy/noisy data.
* Code review fixes.
Co-authored-by: Daniel Rydstrom <daniel.rydstrom@sick.se>
* Fix issue #10114
Convert table change
From:
CV_8U -> HALF
CV_8S -> HALF
CV_16U -> UINT
CV_16S -> UINT
CV_32S -> UINT
CV_32F -> FLOAT
To:
CV_8U -> HALF
CV_8S -> HALF
CV_16U -> UINT
CV_16S -> FLOAT
CV_32S -> FLOAT loss precision
CV_32F -> FLOAT
Signed integer can't be presented well with UINT. Even adjust bias, CV16S and CV32S will be confused when load from exr file.
Also fix CV_8S negative value incorrect bug
* EXR import and export
imread() from EXR returns CV_32F only
imwrite() accepts CV_32 cv::Mat only and stores FLOAT images by default. Add imwrite() flag to store in HALF format.
* fix compiling error
* clean up
* fix EXR import issues
