drive.py

import argparse
import base64
from datetime import datetime
import os
import shutil

import numpy as np
import socketio
import eventlet
import eventlet.wsgi
from PIL import Image
from flask import Flask
from io import BytesIO

from keras.models import load_model
import h5py
from keras import __version__ as keras_version

import cv2
import DetectLaneLines as dl

sio = socketio.Server()
app = Flask(__name__)
model = None
prev_image_array = None

def preprocess_image(img):
    '''
    Method for preprocessing images: this method is the same used in drive.py, except this version uses
    BGR to YUV and drive.py uses RGB to YUV (due to using cv2 to read the image here, where drive.py images are
    received in RGB)
    '''
    new_img = img[50:140,:,:]
    # apply subtle blur
    new_img = cv2.GaussianBlur(new_img, (3,3), 0)
    # scale to 66x200x3 (same as nVidia)
    new_img = cv2.resize(new_img,(200, 66), interpolation = cv2.INTER_AREA)

    new_img = cv2.cvtColor(new_img, cv2.COLOR_RGB2YUV)
    return new_img


class SimplePIController:
    def __init__(self, Kp, Ki):
        self.Kp = Kp
        self.Ki = Ki
        self.set_point = 0.
        self.error = 0.
        self.integral = 0.

    def set_desired(self, desired):
        self.set_point = desired

    def update(self, measurement):
        # proportional error
        self.error = self.set_point - measurement

        # integral error
        self.integral += self.error

        return self.Kp * self.error + self.Ki * self.integral


controller = SimplePIController(0.1, 0.002)
set_speed = 30  # Adjust this for track 2
controller.set_desired(set_speed)


@sio.on('telemetry')
def telemetry(sid, data):
    if data:
        # The current steering angle of the car
        steering_angle = data["steering_angle"]
        # The current throttle of the car
        throttle = data["throttle"]
        # The current speed of the car
        speed = data["speed"]
        # The current image from the center camera of the car
        imgString = data["image"]
        image = Image.open(BytesIO(base64.b64decode(imgString)))
        image_array = np.asarray(image)
        img = preprocess_image(image_array)
        transformed_image_array = img[None, :, :, :]
        old_angle = float(steering_angle)/25 # Convertion from 25 to 1
        pred_angle = float(model.predict(transformed_image_array, batch_size=1))

        # Override oredictions based on current angle and new angle
        if abs(pred_angle) < 0.075:
            new_angle = 0
        elif abs(pred_angle) < 0.12:
            new_angle = pred_angle/3
        else:
            new_angle = (pred_angle - old_angle) * 1.1 + old_angle

        steering_angle = float(new_angle)

        throttle = controller.update(float(speed))

        print(steering_angle, throttle, old_angle)
        send_control(steering_angle, throttle)

        # save frame
        if args.image_folder != '':
            timestamp = datetime.utcnow().strftime('%Y_%m_%d_%H_%M_%S_%f')[:-3]
            image_filename = os.path.join(args.image_folder, timestamp)
            image.save('{}.jpg'.format(image_filename))
    else:
        # NOTE: DON'T EDIT THIS.
        sio.emit('manual', data={}, skip_sid=True)


@sio.on('connect')
def connect(sid, environ):
    print("connect ", sid)
    send_control(0, 0)


def send_control(steering_angle, throttle):
    sio.emit(
        "steer",
        data={
            'steering_angle': steering_angle.__str__(),
            'throttle': throttle.__str__()
        },
        skip_sid=True)


if __name__ == '__main__':
    parser = argparse.ArgumentParser(description='Remote Driving')
    parser.add_argument(
        'model',
        type=str,
        help='Path to model h5 file. Model should be on the same path.'
    )
    parser.add_argument(
        'image_folder',
        type=str,
        nargs='?',
        default='',
        help='Path to image folder. This is where the images from the run will be saved.'
    )
    args = parser.parse_args()

    # check that model Keras version is same as local Keras version
    f = h5py.File(args.model, mode='r')
    model_version = f.attrs.get('keras_version')
    keras_version = str(keras_version).encode('utf8')

    if model_version != keras_version:
        print('You are using Keras version ', keras_version,
              ', but the model was built using ', model_version)

    model = load_model(args.model)

    if args.image_folder != '':
        print("Creating image folder at {}".format(args.image_folder))
        if not os.path.exists(args.image_folder):
            os.makedirs(args.image_folder)
        else:
            shutil.rmtree(args.image_folder)
            os.makedirs(args.image_folder)
        print("RECORDING THIS RUN ...")
    else:
        print("NOT RECORDING THIS RUN ...")

    # wrap Flask application with engineio's middleware
    app = socketio.Middleware(sio, app)

    # deploy as an eventlet WSGI server
    eventlet.wsgi.server(eventlet.listen(('', 4567)), app)