void projectMetadata(const File &src, File &dst)

This is a pure virtual function. It must be overloaded by all derived classes. Project a Template's metadata through the transform, modifying its contents in some way and storing the modified data in dst.

• function definition:

  virtual void projectMetadata(const File &src, File &dst) const = 0
  

• parameters:

  Parameter	Type	Description
  src	const File &	Input File. It is immutable
  dst	File &	Output File. Should contain the modified data from the input template.

• output: (void)

• example:

  class IncrementPropertyTransform : public MetadataTransform
  {
      Q_OBJECT
      Q_PROPERTY(QString key READ get_key WRITE set_key RESET reset_key STORED false)
      BR_PROPERTY(QString, key, "")
  
      void projectMetadata(const File &src, File &dst) const
      {
          dst = src;
          dst.set(key, src.get<int>(key, 0) + 1);
      }
  };
  
  BR_REGISTER(Transform, IncrementPropertyTransform)
  
  MetadataTransform *m_transform = (MetadataTransform *)Transform::make("IncrementProperty(property1)", NULL);
  
  File in("picture.jpg"), out;
  in.set("property1", 10);
  
  m_transform->projectMetadata(in, out);
  out.flat(); // Returns "picture.jpg[property1=11]"
  

void project(const Template &src, Template &dst)

Project a Template through the transform by passing its metadata through projectMetadata and storing the result in dst. All matrices in src are passed unchanged to dst.

• function definition:

  void project(const Template &src, Template &dst) const
  

• parameters:

  Parameter	Type	Description
  src	const Template &	Input Template. It is immutable
  dst	Template &	Output Template. Should contain the modified data from the input template.

• output: (void)