raw_image_augmentation.py

from skimage import io
from skimage import transform as tf
import random
import numpy as np
import md5
import glob


def rotate(image):
    angle = random.randint(1,360)
    return tf.rotate(image,angle)

def shear(image):
    # Create Afine transform
    shear = random.uniform(-0.4,0.4)
    afine_tf = tf.AffineTransform(shear=shear)
    # Apply transform to image data
    modified = tf.warp(image, afine_tf)

    return modified;

def rescale(image):
    factor = random.uniform(0.1,0.9)
    return tf.rescale(image,factor)

def translation(image):
        # Create Afine transform
    tx = random.randint(-40,40)
    ty = random.randint(-40,40)
    trans_factor = (tx,ty)
    trans_tf = tf.AffineTransform(translation=trans_factor)
    # Apply transform to image data
    modified = tf.warp(image, trans_tf)

    return modified;

def piecewise_affine(image):
    rows, cols = image.shape[0], image.shape[1]

    src_cols = np.linspace(0, cols, 20)
    src_rows = np.linspace(0, rows, 10)
    src_rows, src_cols = np.meshgrid(src_rows, src_cols)
    src = np.dstack([src_cols.flat, src_rows.flat])[0]

    # add sinusoidal oscillation to row coordinates
    dst_rows = src[:, 1] - np.sin(np.linspace(0, 3 * np.pi, src.shape[0])) * 50
    dst_cols = src[:, 0]
    dst_rows *= 1.5
    dst_rows -= 1.5 * 50
    dst = np.vstack([dst_cols, dst_rows]).T


    tform = tf.PiecewiseAffineTransform()
    tform.estimate(src, dst)

    out_rows = image.shape[0] - 1.5 * 50
    out_cols = cols
    out = tf.warp(image, tform, output_shape=(out_rows, out_cols))

    return out

def resize(image):
    return tf.resize(image,(512,512))



def data_augment(folder, outfolder):
    number = 0
    paths = glob.glob(folder+"/*.jpg")
    for path in paths:
        print "Processing ", path
        try:
            image = io.imread(path)

            # Rotation 3 images

            rotate1 = rotate(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", rotate1)

            rotate2 = rotate(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", rotate2)

            rotate3 = rotate(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", rotate3)

            # Shear 3 images
            shear1 = shear(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", shear1)

            shear2 = shear(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", shear2)

            shear3 = shear(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", shear3)


            # Rescale 3 images
            rescale1 = rescale(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", rescale1)

            rescale2 = rescale(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", rescale2)

            rescale3 = rescale(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", rescale3)

            #translation 3 images
            translation1 = translation(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", translation1)

            translation2 = translation(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", translation2)

            translation2 = translation(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", translation2)

            #piecewise_affine
            piecewise = piecewise_affine(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", piecewise)

            #piecewise_affine
            resizeimg = resize(image)
            number = number + 1
            name = md5.new(str(number)).hexdigest()
            io.imsave(outfolder + "/" + name + ".jpg", resizeimg)
        except:
            print "False"
            pass