def load_sample(fp: str,
name: str,
img_type: str = '.jpg',
an_type: str = 'labelme') -> Sample:
image = Image.open(os.path.join(fp, name + img_type))
annotation = load_annotation(os.path.join(fp, name), an_type, 'airport')
return Sample(image, annotation)
def mirror_image(sample: Sample) -> Sample:
"""
左右镜像
:param sample:
:return:
"""
image = sample.image
annotation = sample.annotation
return Sample(image.transpose(Image.FLIP_LEFT_RIGHT),
transform_annotation(annotation, 'mirror'))
def rotate_image(sample: Sample) -> Sample:
"""
逆时针旋转90度
:param sample:
:return:
"""
# TODO: bug，旋转y轴坐标向下偏移
image = sample.image
annotation = sample.annotation
rotate = Image.ROTATE_90
return Sample(image.transpose(rotate),
transform_annotation(annotation, 'rotate'))
def resize_image(sample: Sample, percent: float) -> Sample:
"""
百分比重采样
:param sample:
:param percent:
:return:
"""
image = sample.image
annotation = sample.annotation
if percent > 1 or percent <= 0:
raise ValueError('percent must in the range: (0,1]')
image_width, image_height = image.size
new_size = (floor(image_width * percent), floor(image_height * percent))
return Sample(
image.resize(new_size),
transform_annotation(annotation, 'resize', new_size=new_size))
def square_clip(sample: Sample) -> Sample:
image = sample.image
image_width, image_height = image.size
if image_width == image_height:
return sample
annotation = sample.annotation
x, y = floor(image_width / 2), floor(image_height / 2)
new_size = min(image_width, image_height)
x0, y0 = x - floor(new_size / 2), y - floor(new_size / 2)
if x0 < 0:
x0 = 0
if y0 < 0:
y0 = 0
clip_box = (x0, y0, x0 + new_size, y0 + new_size)
return Sample(
image.crop(clip_box),
transform_annotation(annotation, 'clip', clip_img_box=clip_box))
def rotate_image2(sample: Sample, angle=90) -> Sample:
"""
逆时针旋转
:param sample:
:param angle: 旋转角度
:return:
"""
image = sample.image
w, h = image.size
annotation = sample.annotation
if angle > 90 or angle < 0:
raise ValueError('angle must in range [0, 90]')
new_image = image.rotate(angle, expand=True)
nw, nh = new_image.size
return Sample(
new_image,
transform_annotation(annotation,
'rotate2',
a=angle,
w=w,
h=h,
nw=nw,
nh=nh))
def zoom_clip_image(sample: Sample,
ratio: float,
random_shift=False) -> Sample:
"""
zoom, then clip by ratio
:param sample:
:param ratio:
:param random_shift:
:return:
"""
if ratio > 1:
ratio = 1
if ratio < 0:
raise ValueError('ratio must be greater than 0')
image = sample.image
annotation = sample.annotation
labels = annotation.labels
object_extents = None
for label in labels:
if label.auxiliary:
object_extents = label.get_extents()
if object_extents is None:
raise ValueError('can not find auxiliary label')
img_width, img_height = image.size
ob_width = abs(object_extents.x_max - object_extents.x_min)
ob_height = abs(object_extents.y_max - object_extents.y_min)
if ratio == 1:
# 如果目标占满整个子图片，则裁剪成机场范围
clip_img_box = (object_extents.x_min, object_extents.y_min,
object_extents.x_max, object_extents.y_max)
return Sample(
image.crop(clip_img_box),
transform_annotation(annotation, 'clip',
clip_img_box=clip_img_box))
x_mid = object_extents.x_min + floor(ob_width / 2)
y_mid = object_extents.y_min + floor(ob_height / 2)
size = min(img_width, img_height)
if max(ob_width / ratio, ob_height / ratio) < size:
# 符合条件说明大小合适，选择合适的范围即可
size = max(ob_width / ratio, ob_height / ratio)
c_xmin = x_mid - floor(size / 2)
c_ymin = y_mid - floor(size / 2)
c_xmax = x_mid + floor(size / 2)
c_ymax = y_mid + floor(size / 2)
if random_shift is True:
shift_x = random.randint(-floor(ob_width / 2), floor(ob_width / 2))
shift_y = random.randint(-floor(ob_height / 2),
floor(ob_height / 2))
c_xmin = c_xmin + shift_x
c_ymin = c_ymin + shift_y
c_xmax = c_xmax + shift_x
c_ymax = c_ymax + shift_y
if c_xmin < 0:
c_xmin = 0
c_xmax = 2 * floor(size / 2)
if c_ymin < 0:
c_ymin = 0
c_ymax = 2 * floor(size / 2)
if c_xmax > img_width - 1:
c_xmax = img_width - 1
c_xmin = c_xmax - 2 * floor(size / 2)
if c_ymax > img_height - 1:
c_ymax = img_height - 1
c_ymin = c_ymax - 2 * floor(size / 2)
clip_box = (c_xmin, c_ymin, c_xmax, c_ymax)
return Sample(
image.crop(clip_box),
transform_annotation(annotation, 'clip', clip_img_box=clip_box))
return zoom_clip_image(sample, ratio + 0.05, random_shift)