Convert a 1 channel image to a 3 channel image












0















I have a grayscale image that has only 1 channel. I am using a code that expects all images to have three channels. How can I convert my image to a 3 channel image using some Linux commands?



Here is the error I get and I do not want to change the code, rather I want to change the image:



Traceback (most recent call last):
File "get_img_vec.py", line 22, in <module>
nd_arr = img2vec.get_vec(img)
File "../img_to_vec.py", line 43, in get_vec
h_x = self.model(image)
File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torch/nn/modules/module.py", line 477, in __call__
result = self.forward(*input, **kwargs)
File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torchvision-0.2.1-py3.6.egg/torchvision/models/resnet.py", line 139, in forward
File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torch/nn/modules/module.py", line 477, in __call__
result = self.forward(*input, **kwargs)
File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torch/nn/modules/conv.py", line 301, in forward
self.padding, self.dilation, self.groups)
RuntimeError: Given groups=1, weight of size [64, 3, 7, 7], expected input[1, 1, 224, 224] to have 3 channels, but got 1 channels instead


The image:



$ identify 10524.jpg
0524.jpg JPEG 1050x550 1050x550+0+0 8-bit PseudoClass 256c 80.7KB 0.000u 0:00.000


This is the image:



black and white photo of a face










share|improve this question





























    0















    I have a grayscale image that has only 1 channel. I am using a code that expects all images to have three channels. How can I convert my image to a 3 channel image using some Linux commands?



    Here is the error I get and I do not want to change the code, rather I want to change the image:



    Traceback (most recent call last):
    File "get_img_vec.py", line 22, in <module>
    nd_arr = img2vec.get_vec(img)
    File "../img_to_vec.py", line 43, in get_vec
    h_x = self.model(image)
    File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torch/nn/modules/module.py", line 477, in __call__
    result = self.forward(*input, **kwargs)
    File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torchvision-0.2.1-py3.6.egg/torchvision/models/resnet.py", line 139, in forward
    File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torch/nn/modules/module.py", line 477, in __call__
    result = self.forward(*input, **kwargs)
    File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torch/nn/modules/conv.py", line 301, in forward
    self.padding, self.dilation, self.groups)
    RuntimeError: Given groups=1, weight of size [64, 3, 7, 7], expected input[1, 1, 224, 224] to have 3 channels, but got 1 channels instead


    The image:



    $ identify 10524.jpg
    0524.jpg JPEG 1050x550 1050x550+0+0 8-bit PseudoClass 256c 80.7KB 0.000u 0:00.000


    This is the image:



    black and white photo of a face










    share|improve this question



























      0












      0








      0








      I have a grayscale image that has only 1 channel. I am using a code that expects all images to have three channels. How can I convert my image to a 3 channel image using some Linux commands?



      Here is the error I get and I do not want to change the code, rather I want to change the image:



      Traceback (most recent call last):
      File "get_img_vec.py", line 22, in <module>
      nd_arr = img2vec.get_vec(img)
      File "../img_to_vec.py", line 43, in get_vec
      h_x = self.model(image)
      File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torch/nn/modules/module.py", line 477, in __call__
      result = self.forward(*input, **kwargs)
      File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torchvision-0.2.1-py3.6.egg/torchvision/models/resnet.py", line 139, in forward
      File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torch/nn/modules/module.py", line 477, in __call__
      result = self.forward(*input, **kwargs)
      File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torch/nn/modules/conv.py", line 301, in forward
      self.padding, self.dilation, self.groups)
      RuntimeError: Given groups=1, weight of size [64, 3, 7, 7], expected input[1, 1, 224, 224] to have 3 channels, but got 1 channels instead


      The image:



      $ identify 10524.jpg
      0524.jpg JPEG 1050x550 1050x550+0+0 8-bit PseudoClass 256c 80.7KB 0.000u 0:00.000


      This is the image:



      black and white photo of a face










      share|improve this question
















      I have a grayscale image that has only 1 channel. I am using a code that expects all images to have three channels. How can I convert my image to a 3 channel image using some Linux commands?



      Here is the error I get and I do not want to change the code, rather I want to change the image:



      Traceback (most recent call last):
      File "get_img_vec.py", line 22, in <module>
      nd_arr = img2vec.get_vec(img)
      File "../img_to_vec.py", line 43, in get_vec
      h_x = self.model(image)
      File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torch/nn/modules/module.py", line 477, in __call__
      result = self.forward(*input, **kwargs)
      File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torchvision-0.2.1-py3.6.egg/torchvision/models/resnet.py", line 139, in forward
      File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torch/nn/modules/module.py", line 477, in __call__
      result = self.forward(*input, **kwargs)
      File "/scratch/sjn-p3/anaconda/anaconda3/lib/python3.6/site-packages/torch/nn/modules/conv.py", line 301, in forward
      self.padding, self.dilation, self.groups)
      RuntimeError: Given groups=1, weight of size [64, 3, 7, 7], expected input[1, 1, 224, 224] to have 3 channels, but got 1 channels instead


      The image:



      $ identify 10524.jpg
      0524.jpg JPEG 1050x550 1050x550+0+0 8-bit PseudoClass 256c 80.7KB 0.000u 0:00.000


      This is the image:



      black and white photo of a face







      convert image-processing






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited Jan 4 at 10:16









      Zanna

      50.5k13133241




      50.5k13133241










      asked Nov 9 '18 at 18:06









      Mona JalalMona Jalal

      1,19052440




      1,19052440






















          2 Answers
          2






          active

          oldest

          votes


















          1
















          1. Install ImageMagick if needed:



            sudo apt install imagemagick



          (You can also install the latest release from source on Ubuntu 18.04 following this guide)





          1. To separate image channels run:



              convert rose: -channel R -separate separate_red.gif
            convert rose: -channel G -separate separate_green.gif
            convert rose: -channel B -separate separate_blue.gif


            (following this guide)



            or to combine RGB image channels run:



            convert  separate_red.gif separate_green.gif separate_blue.gif 
            -combine -set colorspace sRGB rose_combined.gif


            (following this guide)




          This will work for JPG too. Also you can try combining copies of the same gray-scale images with 3 different channels.






          share|improve this answer

































            0














            The following Python code works:



            import cv2
            import numpy as np
            img = cv2.imread('10524.jpg')
            gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
            img2 = np.zeros_like(img)
            img2[:,:,0] = gray
            img2[:,:,1] = gray
            img2[:,:,2] = gray
            cv2.imwrite('10524.jpg', img2)





            share|improve this answer























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              2 Answers
              2






              active

              oldest

              votes








              2 Answers
              2






              active

              oldest

              votes









              active

              oldest

              votes






              active

              oldest

              votes









              1
















              1. Install ImageMagick if needed:



                sudo apt install imagemagick



              (You can also install the latest release from source on Ubuntu 18.04 following this guide)





              1. To separate image channels run:



                  convert rose: -channel R -separate separate_red.gif
                convert rose: -channel G -separate separate_green.gif
                convert rose: -channel B -separate separate_blue.gif


                (following this guide)



                or to combine RGB image channels run:



                convert  separate_red.gif separate_green.gif separate_blue.gif 
                -combine -set colorspace sRGB rose_combined.gif


                (following this guide)




              This will work for JPG too. Also you can try combining copies of the same gray-scale images with 3 different channels.






              share|improve this answer






























                1
















                1. Install ImageMagick if needed:



                  sudo apt install imagemagick



                (You can also install the latest release from source on Ubuntu 18.04 following this guide)





                1. To separate image channels run:



                    convert rose: -channel R -separate separate_red.gif
                  convert rose: -channel G -separate separate_green.gif
                  convert rose: -channel B -separate separate_blue.gif


                  (following this guide)



                  or to combine RGB image channels run:



                  convert  separate_red.gif separate_green.gif separate_blue.gif 
                  -combine -set colorspace sRGB rose_combined.gif


                  (following this guide)




                This will work for JPG too. Also you can try combining copies of the same gray-scale images with 3 different channels.






                share|improve this answer




























                  1












                  1








                  1









                  1. Install ImageMagick if needed:



                    sudo apt install imagemagick



                  (You can also install the latest release from source on Ubuntu 18.04 following this guide)





                  1. To separate image channels run:



                      convert rose: -channel R -separate separate_red.gif
                    convert rose: -channel G -separate separate_green.gif
                    convert rose: -channel B -separate separate_blue.gif


                    (following this guide)



                    or to combine RGB image channels run:



                    convert  separate_red.gif separate_green.gif separate_blue.gif 
                    -combine -set colorspace sRGB rose_combined.gif


                    (following this guide)




                  This will work for JPG too. Also you can try combining copies of the same gray-scale images with 3 different channels.






                  share|improve this answer

















                  1. Install ImageMagick if needed:



                    sudo apt install imagemagick



                  (You can also install the latest release from source on Ubuntu 18.04 following this guide)





                  1. To separate image channels run:



                      convert rose: -channel R -separate separate_red.gif
                    convert rose: -channel G -separate separate_green.gif
                    convert rose: -channel B -separate separate_blue.gif


                    (following this guide)



                    or to combine RGB image channels run:



                    convert  separate_red.gif separate_green.gif separate_blue.gif 
                    -combine -set colorspace sRGB rose_combined.gif


                    (following this guide)




                  This will work for JPG too. Also you can try combining copies of the same gray-scale images with 3 different channels.







                  share|improve this answer














                  share|improve this answer



                  share|improve this answer








                  edited Jan 4 at 10:20









                  Zanna

                  50.5k13133241




                  50.5k13133241










                  answered Nov 9 '18 at 19:23









                  maturemature

                  1,7381624




                  1,7381624

























                      0














                      The following Python code works:



                      import cv2
                      import numpy as np
                      img = cv2.imread('10524.jpg')
                      gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
                      img2 = np.zeros_like(img)
                      img2[:,:,0] = gray
                      img2[:,:,1] = gray
                      img2[:,:,2] = gray
                      cv2.imwrite('10524.jpg', img2)





                      share|improve this answer




























                        0














                        The following Python code works:



                        import cv2
                        import numpy as np
                        img = cv2.imread('10524.jpg')
                        gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
                        img2 = np.zeros_like(img)
                        img2[:,:,0] = gray
                        img2[:,:,1] = gray
                        img2[:,:,2] = gray
                        cv2.imwrite('10524.jpg', img2)





                        share|improve this answer


























                          0












                          0








                          0







                          The following Python code works:



                          import cv2
                          import numpy as np
                          img = cv2.imread('10524.jpg')
                          gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
                          img2 = np.zeros_like(img)
                          img2[:,:,0] = gray
                          img2[:,:,1] = gray
                          img2[:,:,2] = gray
                          cv2.imwrite('10524.jpg', img2)





                          share|improve this answer













                          The following Python code works:



                          import cv2
                          import numpy as np
                          img = cv2.imread('10524.jpg')
                          gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
                          img2 = np.zeros_like(img)
                          img2[:,:,0] = gray
                          img2[:,:,1] = gray
                          img2[:,:,2] = gray
                          cv2.imwrite('10524.jpg', img2)






                          share|improve this answer












                          share|improve this answer



                          share|improve this answer










                          answered Nov 9 '18 at 20:51









                          Mona JalalMona Jalal

                          1,19052440




                          1,19052440






























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