Changeset 5183

Timestamp:

10/03/07 14:10:35 (6 years ago)

Author:

jgaeddert

Message:

adding functionality to binary sequence

Location:

experimental/components/Packetizer/trunk/Packetizer-metadata/src

Files:

• binary_sequence.c (modified) (3 diffs)
• binary_sequence.h (modified) (2 diffs)

experimental/components/Packetizer/trunk/Packetizer-metadata/src/binary_sequence.c

@@ -22 +22 @@
 #include "binary_sequence.h"
 
+signed int c_bits[16] = {
+    -4, // 0000
+    -2, // 0001
+    -2, // 0010
+     0, // 0011
+    -2, // 0100
+     0, // 0101
+     0, // 0110
+     2, // 0111
+    -2, // 1000
+     0, // 1001
+     0, // 1010
+     2, // 1011
+     0, // 1100
+     2, // 1101
+     2, // 1110
+     4  // 1111
+};
+
 binary_sequence_t * binary_sequence_create()
 {
@@ -41 +60 @@
         printf("ERROR! binary sequence already initialized!\n");
 
-    // initialize length
+    //
+    bs->num_bits = num_bits;
+    
+    // initialize array length
     bs->s_len = num_bits / 8;
+
+    // initialize bit mask
+    bs->bit_mask_last_block = 0x00;
+    unsigned int i;
+    for (i=0; i<(num_bits % 8); i++) {
+        bs->bit_mask_last_block <<=1;
+        bs->bit_mask_last_block &= 0x01;
+    }
 
     // initialze array with zeros
@@ -49 +79 @@
 
 
+void binary_sequence_push(binary_sequence_t * bs, BIT b)
+{
+    //
+    BIT overflow;
+    int i;
+    
+    for (i=bs->s_len; i>0; i--) {
+        overflow = ( (bs->s)[i] & 0x00f0 ) == 0 ? 0 : 1;
+        (bs->s)[i] <<= 1;
+        (bs->s)[i] |= overflow;
+    }
+}
 
+signed int binary_sequence_correlate(binary_sequence_t * bs1, binary_sequence_t * bs2)
+{
+    signed int rxy = 0;
+    unsigned int i;
+    
+    if ( bs1->s_len != bs2->s_len ) {
+        printf("ERROR! binary_sequence_correlate(): binary sequences must be the same length!\n");
+        // throw error
+    }
+    unsigned int c_bits_index;
+    for (i=0; i<(bs1->s_len); i++) {
+        //
+        c_bits_index = (bs1->s)[i] & (bs2->s)[i];
+        if ( i == bs1->s_len )
+            c_bits_index &= bs1->bit_mask_last_block;
+        rxy += c_bits[c_bits_index];
+    }
+    
+    return rxy;
+}
+
+

experimental/components/Packetizer/trunk/Packetizer-metadata/src/binary_sequence.h

@@ -34 +34 @@
 typedef struct binary_sequence binary_sequence_t;
 
+extern signed int c_bits[16];
+
 struct binary_sequence {
     /// sequence array
     UINT8 * s;
-
+    
+    ///
+    unsigned int num_bits;
+    
+    ///
+    UINT8 bit_mask_last_block;
+    
     /// length of array
     unsigned int s_len;
@@ -46 +54 @@
 void binary_sequence_initialize(binary_sequence_t * bs, unsigned int num_bits);
 
-void binary_sequence_destroy(binary_sequence_t * s);
+void binary_sequence_destroy(binary_sequence_t * bs);
 
-void binary_sequence_push(BIT b);
+void binary_sequence_push(binary_sequence_t * bs, BIT b);
 
-signed int binary_sequence_correlate(binary_sequence_t * s1, binary_sequence_t * s2);
+signed int binary_sequence_correlate(binary_sequence_t * bs1, binary_sequence_t * bs2);
 
 #endif