diff --git a/libs/main/core/pichunkstream.cpp b/libs/main/core/pichunkstream.cpp
index c80455d3..7920f1b4 100644
--- a/libs/main/core/pichunkstream.cpp
+++ b/libs/main/core/pichunkstream.cpp
@@ -115,7 +115,16 @@ void PIChunkStream::readAll() {
 
 
 PIChunkStream::~PIChunkStream() {
+}
 
+
+bool PIChunkStream::extract(PIByteArray & data) {
+	if (data.size_s() < 4) return false;
+	data >> tmp_data;
+	if (tmp_data.size_s() < 4) return false;
+	data_ = &tmp_data;
+	_init();
+	return true;
 }
 
 
diff --git a/libs/main/core/pichunkstream.h b/libs/main/core/pichunkstream.h
index 89dad97d..d771143b 100644
--- a/libs/main/core/pichunkstream.h
+++ b/libs/main/core/pichunkstream.h
@@ -67,6 +67,9 @@ public:
 	//! Add data to this chunk strean with ID "id" and value "data"
 	template <typename T> PIChunkStream & add(int id, const T & data) {*this << ChunkConst<T>(id, data); return *this;}
 
+	//! Extract %PIByteArray from "data" and set it current stream. Returns if has data to read.
+	bool extract(PIByteArray & data);
+
 	void setSource(const PIByteArray & data);
 	void setSource(PIByteArray * data);