HDRReader
vtk-examples/Cxx/IO/HDRReader
Description¶
Demonstrates how to read high-dynamic-range imaging files.
A callback is used to print out the color window (move the mouse horizontally over the image) and color level (move the mouse vertically over the image).
This is based on IO/Image/Testing/Cxx/TestHDRReader.cxx in the VTK source files.
Other languages
See (Python)
Question
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Code¶
HDRReader.cxx
#include "vtkHDRReader.h"
#include "vtkImageData.h"
#include "vtkImageViewer.h"
#include "vtkNew.h"
#include "vtkRenderWindowInteractor.h"
#include "vtkRenderer.h"
#include <vtkCallbackCommand.h>
namespace {
class ColorCallback : public vtkCallbackCommand
{
public:
static ColorCallback* New()
{
return new ColorCallback;
}
// Here we Create a vtkCallbackCommand and reimplement it.
void Execute(vtkObject* caller, unsigned long evId, void*) override
{
// Note the use of reinterpret_cast to cast the caller to the expected type.
// Just do this to demonstrate who called callback and the event that
// triggered it.
// std::cout << interactor->GetClassName() << " Event Id: " << evId
// << std::endl;
std::cout << "Color window: " << imageViewer->GetColorWindow();
std::cout << " level: " << imageViewer->GetColorLevel() << std::endl;
}
ColorCallback() : imageViewer(nullptr)
{
}
// Set pointers to any clientData or callData here.
vtkImageViewer* imageViewer;
private:
ColorCallback(const ColorCallback&) = delete;
void operator=(const ColorCallback&) = delete;
};
} // namespace
int main(int argc, char* argv[])
{
if (argc <= 1)
{
cout << "Usage: " << argv[0] << " <hdr file>" << endl;
cout << "For example: Skyboxes/spiaggia_di_mondello_1k.hdr" << std::endl;
return EXIT_FAILURE;
}
std::string filename = argv[1];
vtkNew<vtkHDRReader> reader;
// Check the image can be read
if (!reader->CanReadFile(filename.c_str()))
{
cerr << "CanReadFile failed for " << filename.c_str() << "\n";
return EXIT_FAILURE;
}
reader->SetFileName(filename.c_str());
reader->UpdateInformation();
// Whole extent
const int* we = reader->GetDataExtent();
const int extents[6] = {we[0], we[1], we[2], we[3], 0, 0};
reader->UpdateExtent(extents);
// Visualize
vtkNew<vtkImageViewer> imageViewer;
imageViewer->SetInputData(reader->GetOutput());
imageViewer->SetColorWindow(1);
imageViewer->SetColorLevel(1);
imageViewer->SetPosition(0, 100);
vtkNew<ColorCallback> getColorWindow;
getColorWindow->imageViewer = imageViewer;
vtkNew<vtkRenderWindowInteractor> iren;
imageViewer->SetupInteractor(iren);
imageViewer->GetRenderWindow()->SetWindowName("HDRReader");
imageViewer->Render();
iren->AddObserver(vtkCommand::EndInteractionEvent, getColorWindow);
iren->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
project(HDRReader)
find_package(VTK COMPONENTS
)
if (NOT VTK_FOUND)
message(FATAL_ERROR "HDRReader: Unable to find the VTK build folder.")
endif()
# Prevent a "command line is too long" failure in Windows.
set(CMAKE_NINJA_FORCE_RESPONSE_FILE "ON" CACHE BOOL "Force Ninja to use response files.")
add_executable(HDRReader MACOSX_BUNDLE HDRReader.cxx )
target_link_libraries(HDRReader PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS HDRReader
MODULES ${VTK_LIBRARIES}
)
Download and Build HDRReader¶
Click here to download HDRReader and its CMakeLists.txt file. Once the tarball HDRReader.tar has been downloaded and extracted,
cd HDRReader/build
If VTK is installed:
cmake ..
If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:
cmake -DVTK_DIR:PATH=/home/me/vtk_build ..
Build the project:
make
and run it:
./HDRReader
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.