for #140: try to implement management of DRI frame

inc/MJPEGVideoSource.h

@@ -45,13 +45,15 @@ class MJPEGVideoSource : public JPEGVideoSource
       virtual u_int8_t qFactor() { return 128; };
       virtual u_int8_t width() { return m_width; };
       virtual u_int8_t height() { return m_height; };
+      virtual u_int16_t restartInterval() { return m_restartInterval; }
+
       u_int8_t const* quantizationTables( u_int8_t& precision, u_int16_t& length );
 
    protected:
       MJPEGVideoSource(UsageEnvironment& env, FramedSource* source) : JPEGVideoSource(env),
          m_inputSource(source),
          m_width(0), m_height(0), m_qTableSize(0), m_precision(0),
-         m_type(0)
+         m_type(0), m_restartInterval(0)
       {
          memset(&m_qTable,0,sizeof(m_qTable));
       }
@@ -68,4 +70,5 @@ class MJPEGVideoSource : public JPEGVideoSource
       unsigned int  m_qTableSize;
       unsigned int  m_precision;
       u_int8_t      m_type;
+      u_int16_t     m_restartInterval;
 };

src/MJPEGVideoSource.cpp

@@ -65,11 +65,17 @@ void MJPEGVideoSource::afterGettingFrame(unsigned frameSize,unsigned numTruncate
 		i+=length+2;	       
 	    }
 	    // SOS
-	    else if ( ((i+1) < frameSize) && (fTo[i] == 0xFF) && (fTo[i+1] == 0xDA) ) {            
+	    else if ( ((i+3) < frameSize) && (fTo[i] == 0xFF) && (fTo[i+1] == 0xDA) ) {            
 		int length = (fTo[i+2]<<8)|(fTo[i+3]);		    
 		LOG(DEBUG) << "SOS length:" << length;                
 		
 		headerSize = i+length+2;                
+            // DRI
+	    } else if ( ((i+5) < frameSize) && (fTo[i] == 0xFF) && (fTo[i+1] == 0xDD) ) {
+		m_type |= 0x40;
+		int length = (fTo[i+2]<<8)|(fTo[i+3]);		    
+		m_restartInterval = (fTo[i+4]<<8)|(fTo[i+5]);
+		i+=length+2;	       
 	    } else {
 		i++;
 	    }