如何从1个图像的Y通道和另一个图像的U,V通道创建新图像?

时间:2018-05-20 19:43:09

标签: python python-imaging-library rgb pillow yuv

我有两张图片contentgenerated。我想创建一个新的图像,其中Y通道为generated,U和V通道为content。使用PIL,我认为我应该能够使用.convert('YCbCr')将我的RGB输入图像转换为YUV。然后在我创建新图像后,我可以使用.convert('RGB')将其转换为RGB。

图像以RGB格式输入以下功能:

def original_colors(content, generated):
    generated_y = generated.convert('YCbCr')
    content_uv = content_uv.convert('YCbCr')
    # Combine Y from generated_y with U and V from content_uv
    # and convert the resulting output back to RGB. 
    return output

将频道组合成新图像的最佳/最有效方法是什么?

以下是我采用的解决方案:

# Combine the Y channel of the generated image and the UV/CbCr channels of the
# content image to perform color-independent style transfer.
def original_colors(content, generated):
    content_channels = list(content.convert('YCbCr').split())
    generated_channels = list(generated.convert('YCbCr').split())
    content_channels[0] = generated_channels[0]
    return Image.merge('YCbCr', content_channels).convert('RGB') 

1 个答案:

答案 0 :(得分:2)

如果alpha_composite()函数没有做你想做的事情,那么你可以将图像加载到数据数组中,并使用切片来替换数组的相关部分。以下似乎使用两个图像:

from PIL import Image
import numpy

# open images and make the same size
image1 = Image.open("image1.jpg").resize((256, 256))
image2 = Image.open("image2.jpg").resize((256, 256))

# convert tp YCbCr
image1_y = image1.convert('YCbCr')
image2_y = image2.convert('YCbCr')

# load image data into arrays
image1_y_array = numpy.array(image1_y)
image2_y_array = numpy.array(image2_y)

# show shape and size of arrays
print (image1_y_array.shape)
print (image2_y_array.shape)

#print (image1_y_array[:,:,0])    # uncomment to see actual data
#print (image2_y_array[:,:,0])    # uncomment to see actual data

# replace image 1 Y channel with image 2 Y channel
# assume 1st [0] channel is the Y
image1_y_array[:,:,0] = image2_y_array[:,:,0]

# create new image from the updated array data
new_image1_y = Image.fromarray(image1_y_array)

# and show the result
new_image1_y.show()

# can now convert new_image1_y back to jpeg, etc.

当图像数据加载到数组中时,可以看到来自数组形状输出的3个数据通道:

(256, 256, 3)
(256, 256, 3)

我假设0索引通道是Y通道,如果没有,则根据需要用1或2替换幻数0。

NB显然图像应该是相同的大小。我希望这可能有所帮助。

编辑:

在不使用numpy的情况下也可以做同样的事情:

from PIL import Image

# open images and make the same size
image1 = Image.open("image1.jpg").resize((256, 256))
image2 = Image.open("image2.jpg").resize((256, 256))

# convert tp YCbCr
image1_y = image1.convert('YCbCr')
image2_y = image2.convert('YCbCr')

# split image data
image1_y_data = image1_y.split()
image2_y_data = image2_y.split()

# replace image 1 Y channel with image 2 Y channel
# assume 1st [0] channel is the Y
image1_y_data_list = list(image1_y_data)
image2_y_data_list = list(image2_y_data)

image1_y_data_list[0] = image2_y_data_list[0]

# create new image from the updated data
new_image1_y = Image.merge('YCbCr', image1_y_data_list)

# and show the result
new_image1_y.show()

# can now convert new_image1_y back to jpeg, etc.