# Color Blob and Line Tracking
## Import KOI 2 Library
```python
from future import *
from koi2 import KOI2
```
## Serial Initialization
```python
koi = KOI2(tx, rx)
```
Initializes the serial connection to KOI.
Parameters:
tx: TX Pin, use P2 for Robotbit EDU
rx: RX Pin, use P12 for Robotbit EDU
## Select Color Blob Tracking Mode
```
koi.setModel(16)
```
Sets the KOI mode to Color Blob Tracking.
## Set Color to Track
```
koi.colorSwitch(color)
```
Parameters:
color: Color to track
color
meaning
0
Red
1
Green
2
Blue
3
Yellow
9
Custom(requires calibration)
## Calibrate Custom Color
```
koi.colorCalibration()
```
Calibrates KOI to track a custom color.
## Get Color Blob Data
```
koi.xywh[0]
```
Returns data for the tracked color blob.
Parameters:
data: The type of data to return.
data
Meaning
0
X coordinates
1
Y coordinates
2
Width of blob
3
Height of blob
## Sample Program: Color Blob Tracking
```
from future import *
from koi2 import KOI2
koi = KOI2('P2', 'P12')
koi.setModel(16)
screen.sync = 0
while True:
koi.read_from_uart()
if sensor.btnValue('a'):
koi.colorSwitch(0)
if sensor.btnValue('b'):
koi.colorCalibration()
koi.colorSwitch(9)
screen.fill((0, 0, 0))
screen.text(koi.xywh[0],5,10,1,(255, 255, 255))
screen.text(koi.xywh[1],5,30,1,(255, 255, 255))
screen.text(koi.xywh[2],5,50,1,(255, 255, 255))
screen.text(koi.xywh[3],5,70,1,(255, 255, 255))
screen.refresh()
```
{% file src="" %}
## Select Line Tracking Mode
```
koi.setModel(32)
```
Sets the KOI mode to Color Blob Tracking.
## Set Color to Track
```
koi.lineSwitch(color)
```
Parameters:
color: Color to track
color
meaning
0
Red
1
Green
2
Blue
3
Yellow
9
Custom(requires calibration)
## Calibrate Custom Color
```
koi.colorCalibration()
```
Calibrates KOI to track a custom color.
## Get Line Data
```
koi.xy12[data]
```
Returns data for the tracked line.
Parameters:
data: The type of data to return.
| data | Meaning |
| ---- | -------------- |
| 0 | X1 coordinates |
| 1 | Y1 coordinates |
| 2 | X2 coordinates |
| 3 | Y2 coordinates |
## Sample Program: Line Tracking
```
from future import *
from koi2 import KOI2
koi = KOI2('P2', 'P12')
koi.setModel(32)
screen.sync = 0
while True:
koi.read_from_uart()
if sensor.btnValue('a'):
koi.lineSwitch(3)
if sensor.btnValue('b'):
koi.colorCalibration()
koi.lineSwitch(4)
screen.fill((0, 0, 0))
screen.text(koi.xy12[0],5,10,1,(255, 255, 255))
screen.text(koi.xy12[1],5,30,1,(255, 255, 255))
screen.text(koi.xy12[2],5,50,1,(255, 255, 255))
screen.text(koi.xy12[3],5,70,1,(255, 255, 255))
screen.refresh()
```
{% file src="" %}