title: Writing geotiff is grayscale instead of color python-gdal
body: <p>I am trying to upscale an geotiff, using deep learning network. I read in a color geo-tiff using gdal and process each band separately and write that band back into the new geo-tiff driver. The code snippet that does this is given below.</p>
  <pre><code> # Remove the scale the image and create separate image for each Band
   bands = tiffimg.shape[-1]
  
   #Create TIFF File driver similar to input
   driver = gdal.GetDriverByName(&quot;GTiff&quot;)
   outdata = driver.Create(f'{save_dir}/{imgname}.{fileExtension}', tiffDS.RasterXSize*2, tiffDS.RasterYSize*2, bands, gdal.GDT_UInt16)
   outpng = np.ones((tiffimg.shape[0]*2,tiffimg.shape[1]*2,tiffimg.shape[2]),dtype=tiffimg.dtype)
  
          
          
      for band in range(bands):
          singleBand = tiffimg[:,:,band]
          bandMaxValue = np.ndarray.max(singleBand)
          print(f'Band {band+1} min and max values before processing:{np.ndarray.min(singleBand)} \t {np.ndarray.max(singleBand)}')
          scaledBand = (singleBand).astype(np.float32)/bandMaxValue
          img_lq = np.stack((scaledBand,)*3,axis=-1)
          resizedImg = getSRImage(args, img_lq, imgname) # gets the upscaled band
          resizedImg = (resizedImg[:,:,1]*bandMaxValue).round().astype(tiffimg.dtype)
          print(f'Band {band+1} min and max values After processing:{np.ndarray.min(resizedImg)} \t {np.ndarray.max(resizedImg)}')
          outdata.GetRasterBand(band+1).WriteArray(resizedImg)
          outdata.GetRasterBand(band+1).SetNoDataValue(100000)##if you want these values transparent
          outpng[band] = resizedImg
  
              
   outdata.SetGeoTransform(tiffDS.GetGeoTransform())##sets same geotransform as input
   outdata.SetProjection(tiffDS.GetProjection())##sets same projection as input
   outdata.SetMetadata(tiffDS.GetMetadata())
   outdata.FlushCache() ##saves to disk!!
   cv2.imwrite(f'{save_dir}/backup/{imgname}.png', outpng[:,:,0:3])
  </code></pre>
  <p>But as the title suggest the resulting image has all the same characteristics as the parent image (the data type and the number of bands) but when viewing it, the saved image is a gray scale image and not a color image. Not sure where I am going wrong.</p>
  <p>Any help is greatly appreciated.</p>
  <p>Update 1:
  The output of exiftool for the original image is</p>
  <pre><code>ExifTool Version Number         : 12.44
  File Name                       : sample.tif
  Directory                       : .
  File Size                       : 6.6 MB
  File Modification Date/Time     : 2022:08:31 19:23:36-06:00
  File Access Date/Time           : 2022:08:31 21:51:47-06:00
  File Inode Change Date/Time     : 2022:08:31 19:23:36-06:00
  File Permissions                : -rw-r--r--
  File Type                       : TIFF
  File Type Extension             : tif
  MIME Type                       : image/tiff
  Exif Byte Order                 : Little-endian (Intel, II)
  Subfile Type                    : Full-resolution image
  Image Width                     : 2076
  Image Height                    : 1053
  Bits Per Sample                 : 8 8 8
  Compression                     : Uncompressed
  Photometric Interpretation      : RGB
  Strip Offsets                   : (Binary data 8254 bytes, use -b option to extract)
  Orientation                     : Horizontal (normal)
  Samples Per Pixel               : 3
  Rows Per Strip                  : 1
  Strip Byte Counts               : (Binary data 5264 bytes, use -b option to extract)
  X Resolution                    : 72
  Y Resolution                    : 72
  Planar Configuration            : Chunky
  Resolution Unit                 : inches
  Software                        : Adobe Photoshop CS6 (Windows)
  Modify Date                     : 2022:06:15 14:25:22
  XMP Toolkit                     : Adobe XMP Core 5.3-c011 66.145661, 2012/02/06-14:56:27
  Create Date                     : 2022:06:15 14:13:45+08:00
  Metadata Date                   : 2022:06:15 14:25:22+08:00
  Format                          : image/tiff
  Color Mode                      : RGB
  Instance ID                     : xmp.iid:EF964DEF73ECEC11B05DA55541B9A9AE
  Document ID                     : xmp.did:EE964DEF73ECEC11B05DA55541B9A9AE
  Original Document ID            : xmp.did:EE964DEF73ECEC11B05DA55541B9A9AE
  History Action                  : created, saved
  History Instance ID             : xmp.iid:EE964DEF73ECEC11B05DA55541B9A9AE, xmp.iid:EF964DEF73ECEC11B05DA55541B9A9AE
  History When                    : 2022:06:15 14:13:45+08:00, 2022:06:15 14:25:22+08:00
  History Software Agent          : Adobe Photoshop CS6 (Windows), Adobe Photoshop CS6 (Windows)
  History Changed                 : /
  Pixel Scale                     : 1 1 0
  Model Tie Point                 : 0 0 0 7671 3249 0
  IPTC Digest                     : 00000000000000000000000000000000
  Displayed Units X               : inches
  Displayed Units Y               : inches
  Print Style                     : Centered
  Print Position                  : 0 0
  Print Scale                     : 1
  Global Angle                    : 30
  Global Altitude                 : 30
  URL List                        : 
  Slices Group Name               : 
  Num Slices                      : 1
  Pixel Aspect Ratio              : 1
  Photoshop Thumbnail             : (Binary data 10449 bytes, use -b option to extract)
  Has Real Merged Data            : Yes
  Writer Name                     : Adobe Photoshop
  Reader Name                     : Adobe Photoshop CS6
  Color Space                     : Uncalibrated
  Exif Image Width                : 2076
  Exif Image Height               : 1053
  Geo Tiff Version                : 1.1.0
  GT Model Type                   : Geographic
  GT Raster Type                  : Pixel Is Area
  Geographic Type                 : WGS 84
  Geog Citation                   : WGS 84
  Geog Angular Unit Size          : 4.84813681109536e-06
  Geog Semi Major Axis            : 6378137
  Geog Inv Flattening             : 298.257223563
  Image Size                      : 2076x1053
  Megapixels                      : 2.2
  </code></pre>
  <p>while the up-scaled one is</p>
  <pre><code>ExifTool Version Number         : 12.44
  File Name                       : sample_upscaled.TIF
  Directory                       : .
  File Size                       : 52 MB
  File Modification Date/Time     : 2022:09:01 12:12:57-06:00
  File Access Date/Time           : 2022:09:01 12:12:59-06:00
  File Inode Change Date/Time     : 2022:09:01 12:12:57-06:00
  File Permissions                : -rw-r--r--
  File Type                       : TIFF
  File Type Extension             : tif
  MIME Type                       : image/tiff
  Exif Byte Order                 : Little-endian (Intel, II)
  Image Width                     : 4152
  Image Height                    : 2106
  Bits Per Sample                 : 16 16 16
  Compression                     : Uncompressed
  Photometric Interpretation      : BlackIsZero
  Strip Offsets                   : (Binary data 18508 bytes, use -b option to extract)
  Samples Per Pixel               : 3
  Rows Per Strip                  : 1
  Strip Byte Counts               : (Binary data 12635 bytes, use -b option to extract)
  Planar Configuration            : Chunky
  Extra Samples                   : Unknown (0 0)
  Sample Format                   : Unsigned; Unsigned; Unsigned
  GDAL No Data                    : 100000
  Image Size                      : 4152x2106
  Megapixels                      : 8.7 
  </code></pre>
  <p>Solution Update:</p>
  <p>As suggested in the comments, the &quot;Photometric interpretation&quot; was the problem. Added &quot;Photometric interpretation=RGB&quot; while creating the driver. which solved the issue.</p>
  <pre><code>driver = gdal.GetDriverByName(&quot;GTiff&quot;)
  options = ['PHOTOMETRIC=RGB', 'PROFILE=GeoTIFF']
  outdata = driver.Create(f'{save_dir}/{imgname}.{fileExtension}', tiffDS.RasterXSize*2, tiffDS.RasterYSize*2, bands, gdal.GDT_UInt16, options=options)
  </code></pre>