1 files changed, 130 insertions, 0 deletions
diff --git a/mpeglib/lib/mpegplay/motionVector.cpp b/mpeglib/lib/mpegplay/motionVector.cpp
new file mode 100644
index 00000000..ebec0369
--- /dev/null
+++ b/mpeglib/lib/mpegplay/motionVector.cpp
@@ -0,0 +1,130 @@
+/*
+  class for motionvectors
+  Copyright (C) 1999  Martin Vogt
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Library General Public License as published by
+  the Free Software Foundation.
+
+  For more information look at the file COPYRIGHT in this package
+
+ */
+
+
+#include "motionVector.h"
+
+
+
+
+
+MotionVector::MotionVector() {
+}
+
+
+MotionVector::~MotionVector() {
+}
+
+
+
+/*
+ *--------------------------------------------------------------
+ *
+ * ComputeVector --
+ *
+ *	Computes motion vector given parameters previously parsed
+ *      and reconstructed.
+ *
+ * Results:
+ *      Reconstructed motion vector info is put into recon_* parameters
+ *      passed to this function. Also updated previous motion vector
+ *      information.
+ *
+ * Side effects:
+ *      None.
+ *
+ *--------------------------------------------------------------
+ */
+void MotionVector::computeVector(int* recon_right_ptr,
+				 int* recon_down_ptr, 
+				 int& recon_right_prev, 
+				 int& recon_down_prev,
+				 unsigned int& f, 
+				 unsigned int& full_pel_vector, 
+				 int& motion_h_code, 
+				 int& motion_v_code, 
+				 unsigned int& motion_h_r, 
+				 unsigned int& motion_v_r) {
+
+
+  int comp_h_r, comp_v_r;						
+  int right_little, right_big, down_little, down_big;			
+  int max, min, new_vector;						
+									
+  /* The following procedure for the reconstruction of motion vectors 	
+     is a direct and simple implementation of the instructions given	
+     in the mpeg December 1991 standard draft. 				
+  */									
+									
+  if (f == 1 || motion_h_code == 0)					
+    comp_h_r = 0;							
+  else 									
+    comp_h_r = f - 1 - motion_h_r;					
+									
+  if (f == 1 || motion_v_code == 0)					
+    comp_v_r = 0;							
+  else 									
+    comp_v_r = f - 1 - motion_v_r;					
+									
+  right_little = motion_h_code * f;					
+  if (right_little == 0)						
+    right_big = 0;							
+  else {								
+    if (right_little > 0) {						
+      right_little = right_little - comp_h_r;				
+      right_big = right_little - 32 * f;				
+    }									
+    else {								
+      right_little = right_little + comp_h_r;				
+      right_big = right_little + 32 * f;				
+    }									
+  }									
+							 		
+  down_little = motion_v_code * f;					
+  if (down_little == 0)							
+    down_big = 0;							
+  else {								
+    if (down_little > 0) {						
+      down_little = down_little - comp_v_r;				
+      down_big = down_little - 32 * f;					
+    }									
+    else {								
+      down_little = down_little + comp_v_r;				
+      down_big = down_little + 32 * f;					
+    }									
+  }									
+  									
+  max = 16 * f - 1;							
+  min = -16 * f;							
+									
+  new_vector = recon_right_prev + right_little;				
+									
+  if (new_vector <= max && new_vector >= min)				
+    *recon_right_ptr = recon_right_prev + right_little;			
+                      /* just new_vector */				
+  else									
+    *recon_right_ptr = recon_right_prev + right_big;			
+  recon_right_prev = *recon_right_ptr;					
+  if (full_pel_vector)							
+    *recon_right_ptr = *recon_right_ptr << 1;				
+									
+  new_vector = recon_down_prev + down_little;				
+  if (new_vector <= max && new_vector >= min)				
+    *recon_down_ptr = recon_down_prev + down_little;			
+                      /* just new_vector */				
+  else									
+    *recon_down_ptr = recon_down_prev + down_big;			
+  recon_down_prev = *recon_down_ptr;					
+  if (full_pel_vector)							
+    *recon_down_ptr = *recon_down_ptr << 1;				
+
+}