Romain Berrada / Morse Featured

Morse Encoder/Decoder Library. Transforms char array to binary array and vice-versa.

A Morse Encoding/Decoding Library \n Transforms char arrays into bool arrays and vice-versa

Morse code taken from http://en.wikipedia.org/wiki/Morse_code Added some more characters :
- : DOT DOT DASH DASH
_ : DASH DASH DASH DOT
. : DASH DASH DASH DASH
/ : DOT DASH DOT DASH
@ : DOT DOT DOT DASH DOT
? : DOT DOT DASH DOT DOT

Here is an quick hello-world that show how to use this library

#include "mbed.h
#include "Morse.h"
    
Serial pc(USBTX, USBRX);
    
int main() {
    int i;
    Morse_data* data;
    char message[] = "Hello World";
    
    data = morse_create(morse_getBoolSize(message));
    morse_encode(message, data);
    for (i=0; i<data->length; i++) pc.printf("%d", data->data[i]);
    
    morse_decode(data, message);
    pc.printf("\nMessage was : %s\n", message);
    
    while(1);
}

Diff: MorseDecoder.cpp

Revision:
1:84ef66bf435d
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MorseDecoder.cpp	Thu Sep 18 17:26:24 2014 +0000
@@ -0,0 +1,135 @@
+/* 
+    Copyright (c) 2014 Romain Berrada
+    
+    Permission is hereby granted, free of charge, to any person obtaining a copy of this software 
+    and associated documentation files (the "Software"), to deal in the Software without restriction, 
+    including without limitation the rights to use, copy, modify, merge, publish, distribute, 
+    sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is 
+    furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included in all copies or 
+    substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING 
+    BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
+    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
+    DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
+    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+#include "Morse.h"
+#include "mbed.h"
+
+struct _morse_tree {
+    char value;
+    const struct _morse_tree* dot;
+    const struct _morse_tree* dash;
+};
+
+// Depth 5 of the tree
+static const struct _morse_tree _morse_tree_1 = {'1', 0, 0};
+static const struct _morse_tree _morse_tree_2 = {'2', 0, 0};
+static const struct _morse_tree _morse_tree_3 = {'3', 0, 0};
+static const struct _morse_tree _morse_tree_4 = {'4', 0, 0};
+static const struct _morse_tree _morse_tree_5 = {'5', 0, 0};
+static const struct _morse_tree _morse_tree_6 = {'6', 0, 0};
+static const struct _morse_tree _morse_tree_7 = {'7', 0, 0};
+static const struct _morse_tree _morse_tree_8 = {'8', 0, 0};
+static const struct _morse_tree _morse_tree_9 = {'9', 0, 0};
+static const struct _morse_tree _morse_tree_0 = {'0', 0, 0};
+static const struct _morse_tree _morse_tree_AR= {'@', 0, 0};                           // @ added as DOT,DOT,DOT,DASH,DOT
+static const struct _morse_tree _morse_tree_IN= {'?', 0, 0};                           // ? added as DOT,DOT,DASH,DOT,DOT
+
+// Depth 4 of the tree
+static const struct _morse_tree _morse_tree_H = {'H', &_morse_tree_5, &_morse_tree_4};
+static const struct _morse_tree _morse_tree_V = {'V',&_morse_tree_AR ,&_morse_tree_3};
+static const struct _morse_tree _morse_tree_F = {'F',&_morse_tree_IN, 0};
+static const struct _morse_tree _morse_tree_MN= {'-', 0,              &_morse_tree_2}; // - added as DOT,DOT,DASH,DASH
+static const struct _morse_tree _morse_tree_L = {'L', 0,              0};
+static const struct _morse_tree _morse_tree_SL= {'/', 0,              0};              // / added as DOT,DASH,DOT,DASH
+static const struct _morse_tree _morse_tree_P = {'P', 0,              0};
+static const struct _morse_tree _morse_tree_J = {'J', 0,              &_morse_tree_1};
+static const struct _morse_tree _morse_tree_B = {'B', &_morse_tree_6, 0};
+static const struct _morse_tree _morse_tree_X = {'X', 0, 0};
+static const struct _morse_tree _morse_tree_C = {'C', 0, 0};
+static const struct _morse_tree _morse_tree_Y = {'Y', 0, 0};
+static const struct _morse_tree _morse_tree_Z = {'Z', &_morse_tree_7, 0};
+static const struct _morse_tree _morse_tree_Q = {'Q', 0, 0};
+static const struct _morse_tree _morse_tree_UN= {'_', &_morse_tree_8, 0};              // _ added as DASH,DASH,DASH,DOT
+static const struct _morse_tree _morse_tree_DO= {'.', &_morse_tree_9, &_morse_tree_0}; // . added as DASH,DASH,DASH,DASH
+
+// Depth 3 of the tree
+static const struct _morse_tree _morse_tree_S = {'S', &_morse_tree_H, &_morse_tree_V};
+static const struct _morse_tree _morse_tree_U = {'U', &_morse_tree_F, &_morse_tree_MN};
+static const struct _morse_tree _morse_tree_R = {'R', &_morse_tree_L, &_morse_tree_SL};
+static const struct _morse_tree _morse_tree_W = {'W', &_morse_tree_P, &_morse_tree_J};
+static const struct _morse_tree _morse_tree_D = {'D', &_morse_tree_B, &_morse_tree_X};
+static const struct _morse_tree _morse_tree_K = {'K', &_morse_tree_C, &_morse_tree_Y};
+static const struct _morse_tree _morse_tree_G = {'G', &_morse_tree_Z, &_morse_tree_Q};
+static const struct _morse_tree _morse_tree_O = {'O', &_morse_tree_UN,&_morse_tree_DO};
+
+// Depth 2 of the tree
+static const struct _morse_tree _morse_tree_I = {'I', &_morse_tree_S, &_morse_tree_U};
+static const struct _morse_tree _morse_tree_A = {'A', &_morse_tree_R, &_morse_tree_W};
+static const struct _morse_tree _morse_tree_N = {'N', &_morse_tree_D, &_morse_tree_K};
+static const struct _morse_tree _morse_tree_M = {'M', &_morse_tree_G, &_morse_tree_O};
+
+// Depth 1 of the tree
+static const struct _morse_tree _morse_tree_E = {'E', &_morse_tree_I, &_morse_tree_A};
+static const struct _morse_tree _morse_tree_T = {'T', &_morse_tree_N, &_morse_tree_M};
+
+static const struct _morse_tree _morse_tree_root = {'#', &_morse_tree_E, &_morse_tree_T};
+
+unsigned int morse_getWordSize(Morse_data* data) {
+    unsigned int i;
+    unsigned int blank_counter=0;
+    unsigned int size=0;
+    
+    for (i=0; i<data->length; i++) {
+        if (data->data[i]==false) blank_counter++;
+        else { // else true
+            // checks all the blanks so far, and then reset the counter
+            if (blank_counter==3) size++; // if blanks to separate two chars
+            else if (blank_counter==7) size+=2; // if blanks for a space : acknowledge the space and the char before the space
+            blank_counter=0;
+        }
+    }
+    size++; // acknowledge the last char
+    if (blank_counter>=7) size++;
+    return size;
+}
+
+void morse_decode(Morse_data* data, char* word) {
+    unsigned int i;
+    unsigned int char_i=0;
+    unsigned int false_counter=0;
+    unsigned int true_counter=0;
+    const struct _morse_tree* tree = &_morse_tree_root; // CHANGE TO THE BINRARY TREE IMPLEMENTATION AND PUT THE ROOT INSTEAD
+
+    for (i=0; i<data->length; i++) {
+        if (data->data[i]==false) {
+            // if false, increase the false_counter, manage the number of true and false before, and reset the true_counter
+            false_counter++;
+            
+            if (true_counter==1) tree = tree->dot;
+            else if (true_counter==3) tree = tree->dash;
+            
+            if (false_counter==3) {
+                word[char_i++] = tree->value;
+                tree = &_morse_tree_root;
+            }
+            else if (false_counter==7) word[char_i++] = ' ';
+
+            true_counter=0;
+        }
+        else { // else true
+            true_counter++;
+            false_counter=0;
+        }   
+    }
+    
+    if (true_counter==1) word[char_i++] = tree->dot->value;
+    else if (true_counter==3) word[char_i++] = tree->dash->value;
+
+    word[char_i] = '\0'; // finally, end the char array
+}