Diff: LineScan.cpp

Revision:

8:b9ec2f3e12b6

Parent:

7:7d3b6edd783e

Child:

9:5226617d2019

--- a/LineScan.cpp	Tue Mar 31 23:34:18 2015 +0000
+++ b/LineScan.cpp	Thu Apr 02 18:38:29 2015 +0000
@@ -5,7 +5,9 @@
 */
 #include "LineScan.h"
 
-#define MEAN_REF 15000      //ideal difference we should see
+#define THRESH 10000
+
+#define MEAN_REF 30000      //ideal difference we should see
 #define CAM_CTRL_GAIN 0.001 //should be small
 
 uint16_t read1Bit(AnalogIn cam, DigitalOut *camClk){
@@ -29,24 +31,25 @@
     *camClk = 0;
 }
 
-int processFn(uint16_t *array, int arraySz, int* exposure){
-    int avg[NUM_PIX];
-    int diff[NUM_PIX];
+float processFn(uint16_t *array, int arraySz, int* exposure){
+    int frameLen = NUM_PIX -  2 * SKIP;
+    int avg[frameLen];
+    int diff[frameLen];
     int highest = 0;
     int lowest = 0;
-    int h_idx = NUM_PIX/2;
-    int l_idx = NUM_PIX/2;
+    int h_idx = frameLen/2;
+    int l_idx = frameLen/2;
     
     //for AGC
     float exposureChange;
     
     //Just finds line center, does not track crossings (needs this feature)
     if(array){
-        avg[0] = array[0];
+        avg[0] = array[SKIP - 1]/2 + array[SKIP]/2;
         diff[0] = 0;
         
-        for(int i = 1; i < NUM_PIX; i++){
-            avg[i] = array[i - 1]/2 + array[i]/2;   //smoothing
+        for(int i = 1; i < frameLen; i++){
+            avg[i] = array[i - 1 + SKIP]/2 + array[i + SKIP]/2;   //smoothing
             diff[i] = avg[i - 1] - avg[i];          //differential
             
             if(diff[i] > highest){
@@ -58,7 +61,7 @@
                 l_idx = i;
             }
         }
-        exposureChange = ((float)(MEAN_REF - highest)) * CAM_CTRL_GAIN;    //AGC, simple proportional controller
+        exposureChange = ((float)(MEAN_REF - highest + lowest)) * CAM_CTRL_GAIN;    //AGC, simple proportional controller
         *exposure += (int)exposureChange;
         if(*exposure <= 0)
             *exposure = 1;
@@ -66,13 +69,13 @@
             *exposure = 40;
     }
     
-    return (h_idx + l_idx)/2;
+    return ((float)(h_idx + l_idx)) / (2.0 * (float)frameLen);    //0 is center
 }
 
 //call after integration time is done, returns index of array line is expected to be at and new exposure time
-int getLinePos(AnalogIn cam, DigitalOut *camSi, DigitalOut *camClk, int *exposure){ // telemetry::NumericArray<uint16_t, 128> &tele_linescan){
+float getLinePos(AnalogIn cam, DigitalOut *camSi, DigitalOut *camClk, int *exposure){ // telemetry::NumericArray<uint16_t, 128> &tele_linescan){
     uint16_t lineAry[NUM_PIX];
-    int position;
+    float position;
     
     //read 
     startRead(camSi, camClk);