我正在创建一个映射函数，它扩充数据集中的每个图像，然后由 tf.numpy_function 包装以创建一个 tensorflow 操作。现在这个 tensorflow op 被传递给 tf.data.Dataset.map 函数
我遇到了一种奇怪的行为，因为代码有时会运行并且有时会显示错误。
transformations = Compose([
Rotate(limit=40),
RandomBrightness(limit=0.1),
JpegCompression(quality_lower=85, quality_upper=100, p=0.5),
HueSaturationValue(hue_shift_limit=20, sat_shift_limit=30, val_shift_limit=20, p=0.5),
RandomContrast(limit=0.2, p=0.5),
HorizontalFlip(),
])
def aug(image):
aug_img = transformations(image=image)['image']
aug_img = tf.image.convert_image_dtype(aug_img, 'float32')
return aug_img
def tf_augment(image,label):
aug_img = tf.numpy_function(func = aug, inp =[image], Tout =tf.float32)
return aug_img,label
augmented_ds = data.batch(10).map(tf_augment,num_parallel_calls=AUTOTUNE)
it = iter(augmented_ds)
batch = next(it)
images,labels = batch
for image,label in zip(images,labels):
show_image(image,label)
tf.data.Dataset对象data由image,label元组组成。我已经对图像进行了预处理，data以使每个图像都具有相同的大小，这样做是为了确保data可以对图像进行批处理。aug是一个增广函数，它image取自data
所以，在我的例子aug中是映射函数。现在aug必须在将映射应用于data.
tf_augment是将传递给data.map方法的张量流操作
为了对映射进行矢量化，我想data在将映射应用到它之前对第一个进行批处理。所以，我data.batch.map先使用，然后再申请map。
现在是最后一段代码
augmented_ds = data.batch(10).map(tf_augment,num_parallel_calls=AUTOTUNE)
it = iter(augmented_ds)
batch = next(it)
images,labels = batch
for image,label in zip(images,labels):
show_image(image,label)
有时运行并在其他时间抛出错误。
它抛出的错误是
UnknownError Traceback (most recent call last)
~\anaconda3\envs\tf23\lib\site-packages\tensorflow\python\eager\context.py in execution_mode(mode)
2101 ctx.executor = executor_new
-> 2102 yield
2103 finally:
~\anaconda3\envs\tf23\lib\site-packages\tensorflow\python\data\ops\iterator_ops.py in _next_internal(self)
754 # handles execute on the same device as where the resource is placed.
--> 755 ret = gen_dataset_ops.iterator_get_next(
756 self._iterator_resource,
~\anaconda3\envs\tf23\lib\site-packages\tensorflow\python\ops\gen_dataset_ops.py in iterator_get_next(iterator, output_types, output_shapes, name)
2609 except _core._NotOkStatusException as e:
-> 2610 _ops.raise_from_not_ok_status(e, name)
2611 except _core._FallbackException:
~\anaconda3\envs\tf23\lib\site-packages\tensorflow\python\framework\ops.py in raise_from_not_ok_status(e, name)
6842 # pylint: disable=protected-access
-> 6843 six.raise_from(core._status_to_exception(e.code, message), None)
6844 # pylint: enable=protected-access
~\anaconda3\envs\tf23\lib\site-packages\six.py in raise_from(value, from_value)
UnknownError: error: OpenCV(4.4.0) C:\Users\appveyor\AppData\Local\Temp\1\pip-req-build-k8sx3e60\opencv\modules\imgproc\src\imgwarp.cpp:2594: error: (-215:Assertion failed) src.cols > 0 && src.rows > 0 in function 'cv::warpAffine'
Traceback (most recent call last):
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\tensorflow\python\ops\script_ops.py", line 244, in __call__
ret = func(*args)
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\tensorflow\python\autograph\impl\api.py", line 302, in wrapper
return func(*args, **kwargs)
File "<ipython-input-68-80185d06bd35>", line 2, in aug
aug_img = transformations(image=image)['image']
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\core\composition.py", line 176, in __call__
data = t(force_apply=force_apply, **data)
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\core\transforms_interface.py", line 87, in __call__
return self.apply_with_params(params, **kwargs)
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\core\transforms_interface.py", line 100, in apply_with_params
res[key] = target_function(arg, **dict(params, **target_dependencies))
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\augmentations\transforms.py", line 526, in apply
return F.rotate(img, angle, interpolation, self.border_mode, self.value)
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\augmentations\functional.py", line 70, in wrapped_function
result = func(img, *args, **kwargs)
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\augmentations\functional.py", line 202, in rotate
return warp_fn(img)
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\augmentations\functional.py", line 188, in __process_fn
img = process_fn(img, **kwargs)
cv2.error: OpenCV(4.4.0) C:\Users\appveyor\AppData\Local\Temp\1\pip-req-build-k8sx3e60\opencv\modules\imgproc\src\imgwarp.cpp:2594: error: (-215:Assertion failed) src.cols > 0 && src.rows > 0 in function 'cv::warpAffine'
[[{{node PyFunc}}]] [Op:IteratorGetNext]
During handling of the above exception, another exception occurred:
UnknownError Traceback (most recent call last)
<ipython-input-73-82392f6b5110> in <module>
1 augmented_ds = resized_ds.batch(10).map(tf_augment,num_parallel_calls=AUTOTUNE)
2 it = iter(augmented_ds)
----> 3 batch = next(it)
4 images,labels = batch
5 images.shape
~\anaconda3\envs\tf23\lib\site-packages\tensorflow\python\data\ops\iterator_ops.py in __next__(self)
734
735 def __next__(self): # For Python 3 compatibility
--> 736 return self.next()
737
738 def _next_internal(self):
~\anaconda3\envs\tf23\lib\site-packages\tensorflow\python\data\ops\iterator_ops.py in next(self)
770 def next(self):
771 try:
--> 772 return self._next_internal()
773 except errors.OutOfRangeError:
774 raise StopIteration
~\anaconda3\envs\tf23\lib\site-packages\tensorflow\python\data\ops\iterator_ops.py in _next_internal(self)
762 return self._element_spec._from_compatible_tensor_list(ret) # pylint: disable=protected-access
763 except AttributeError:
--> 764 return structure.from_compatible_tensor_list(self._element_spec, ret)
765
766 @property
~\anaconda3\envs\tf23\lib\contextlib.py in __exit__(self, type, value, traceback)
129 value = type()
130 try:
--> 131 self.gen.throw(type, value, traceback)
132 except StopIteration as exc:
133 # Suppress StopIteration *unless* it's the same exception that
~\anaconda3\envs\tf23\lib\site-packages\tensorflow\python\eager\context.py in execution_mode(mode)
2103 finally:
2104 ctx.executor = executor_old
-> 2105 executor_new.wait()
2106
2107
~\anaconda3\envs\tf23\lib\site-packages\tensorflow\python\eager\executor.py in wait(self)
65 def wait(self):
66 """Waits for ops dispatched in this executor to finish."""
---> 67 pywrap_tfe.TFE_ExecutorWaitForAllPendingNodes(self._handle)
68
69 def clear_error(self):
UnknownError: error: OpenCV(4.4.0) C:\Users\appveyor\AppData\Local\Temp\1\pip-req-build-k8sx3e60\opencv\modules\imgproc\src\imgwarp.cpp:2594: error: (-215:Assertion failed) src.cols > 0 && src.rows > 0 in function 'cv::warpAffine'
Traceback (most recent call last):
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\tensorflow\python\ops\script_ops.py", line 244, in __call__
ret = func(*args)
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\tensorflow\python\autograph\impl\api.py", line 302, in wrapper
return func(*args, **kwargs)
File "<ipython-input-68-80185d06bd35>", line 2, in aug
aug_img = transformations(image=image)['image']
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\core\composition.py", line 176, in __call__
data = t(force_apply=force_apply, **data)
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\core\transforms_interface.py", line 87, in __call__
return self.apply_with_params(params, **kwargs)
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\core\transforms_interface.py", line 100, in apply_with_params
res[key] = target_function(arg, **dict(params, **target_dependencies))
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\augmentations\transforms.py", line 526, in apply
return F.rotate(img, angle, interpolation, self.border_mode, self.value)
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\augmentations\functional.py", line 70, in wrapped_function
result = func(img, *args, **kwargs)
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\augmentations\functional.py", line 202, in rotate
return warp_fn(img)
File "C:\Users\aksha\anaconda3\envs\tf23\lib\site-packages\albumentations\augmentations\functional.py", line 188, in __process_fn
img = process_fn(img, **kwargs)
cv2.error: OpenCV(4.4.0) C:\Users\appveyor\AppData\Local\Temp\1\pip-req-build-k8sx3e60\opencv\modules\imgproc\src\imgwarp.cpp:2594: error: (-215:Assertion failed) src.cols > 0 && src.rows > 0 in function 'cv::warpAffine'
[[{{node PyFunc}}]]
我还附上了 colab 笔记本的链接。请复制它。 合作实验室