如何读取存储为一维数组的 hdf5 文件。并以图像形式查看它们？

Question

我有一个大型图像分类数据集，以

.hdf5

格式存储。数据集的标签和图像存储在

.hdf5

文件中。我无法查看图像，因为它们以数组的形式存储。我使用的数据集读取代码如下，

import h5py
import numpy
f = h5py.File('data/images.hdf5', 'r')
print(list(f.keys()))

['datasets']

group = f['datasets']
list(group.keys())

['car']

现在当我阅读该组时

cars

我有以下输出，

data = group['car']
data.shape,data[0].shape,data[1].shape

((51,), (383275,), (257120,)

因此，标签

51

看起来有

car

图像，并且图像存储为

383275

和

257120

维数组，没有有关其高度和宽度尺寸的信息。我想再次将图像保存为 RGB。 接下来，按照代码here，我尝试读取图像。

import numpy as np
from PIL import Image

# hdf = h5py.File("Sample.h5",'r')
array = data[0]
img = Image.fromarray(array.astype('uint8'), 'RGB')
img.save("yourimage.thumbnail", "JPEG")
img.show()

不幸的是，收到以下错误。

File /usr/local/lib/python3.8/dist-packages/PIL/Image.py:784, in Image.frombytes(self, data, decoder_name, *args)
    781 s = d.decode(data)
    783 if s[0] >= 0:
--> 784     raise ValueError("not enough image data")
    785 if s[1] != 0:
    786     raise ValueError("cannot decode image data")

ValueError: not enough image data

参考资料我已经检查了hdf组帮助库等。 任何帮助都会非常有用。谢谢。

Answer 1

import h5py
import numpy as np
from PIL import Image

# Open the HDF5 file
with h5py.File('data/images.hdf5', 'r') as f:
    # Access the dataset containing images
    data = f['datasets']['car']

    # Iterate through each image stored as a 1-D array
    for i in range(len(data)):
        # Assuming you know the correct dimensions. For example, 256x256 with 3 color channels
        height, width, channels = 256, 256, 3

        # Reshape the 1-D array into a 3-D array with the shape (height, width, channels)
        image_array = np.reshape(data[i], (height, width, channels))

        # Convert the numpy array into a PIL image
        img = Image.fromarray(image_array.astype('uint8'), 'RGB')

        # Save or display the image
        img.save(f'image_{i}.png')
        img.show()  # Remove this line if you don't want to display the image