TIFFReadRGBAImage - read and decode an image into a fixed-format raster

       LibTIFF contributors

       1988-2022, LibTIFF contributors

4.7                                               Apr 30, 2025                          TIFFREADRGBAIMAGE(3tiff)

TIFFReadRGBAImage()  reads  a  strip-  or  tile-based  image  into memory, storing the result in the user
       supplied raster.  The raster is assumed to be an array of width × height 32-bit entries, where width must
       be less than or equal to the width of the image (height  may  be  any  non-zero  size).   If  the  raster
       dimensions  are  smaller  than  the image, the image data is cropped to the raster bounds.  If the raster
       height is greater than that of the image, then the image data are placed in the lower part of the raster.
       (Note that the raster is assume to be organized such that the pixel at location (x, y) is raster  [  y  ×
       width + x ]; with the raster origin in the lower-left hand corner.)

       TIFFReadRGBAImageOriented()  works  like  TIFFReadRGBAImage() except that the user can specify the raster
       origin position with the orientation parameter. Four orientations are supported:

       • ORIENTATION_TOPLEFT: origin in top-left corner,

       • ORIENTATION_TOPRIGHT: origin in top-right corner,

       • ORIENTATION_BOTLEFT: origin in bottom-left corner

       • ORIENTATION_BOTRIGHT: origin in bottom-right corner.

       If you choose ORIENTATION_BOTLEFT, the result will be the same as returned by the TIFFReadRGBAImage().

       Raster pixels are 8-bit packed red, green, blue, alpha samples.  The macros TIFFGetR, TIFFGetG, TIFFGetB,
       and TIFFGetA should be used to access  individual  samples.   Images  without  Associated  Alpha  matting
       information have a constant Alpha of 1.0 (255).

       TIFFReadRGBAImage()  converts  non-8-bit  images  by scaling sample values.  Palette, grayscale, bilevel,
       CMYK, and YCbCr images are converted to RGB transparently.  Raster pixels are returned uncorrected by any
       colorimetry information present in the directory.

       The parameter stopOnError specifies how to act if an error is encountered while  reading  the  image.  If
       stopOnError  is  non-zero, then an error will terminate the operation; otherwise TIFFReadRGBAImage() will
       continue processing data until all the possible data in the image have been requested.

       All error messages are directed to the TIFFErrorExtR() routine.

       "Sorry,cannothandle%d-bitpictures":
          The image had BitsPerSample other than 1, 2, 4, 8, or 16.

       "Sorry,cannothandle%d-channelimages":
          The image had SamplesPerPixel other than 1, 3, or 4.

       Missingneeded"PhotometricInterpretation"tag:
          The image did not have a tag that describes how to display the data.

       No"PhotometricInterpretation"tag,assumingRGB:
          The image was missing a tag that describes how to display it, but because it has 3 or 4 samples/pixel,
          it is assumed to be RGB.

       No"PhotometricInterpretation"tag,assumingmin-is-black:
          The image was missing a tag that describes how to display it, but because it has 1 sample/pixel, it is
          assumed to be a grayscale or bilevel image.

       "Nospaceforphotometricconversiontable":
          There was insufficient memory for a table used to convert image samples to 8-bit RGB.

       Missingrequired"Colormap"tag:
          A Palette image did not have a required Colormap tag.

       "Nospacefortilebuffer":
          There was insufficient memory to allocate an i/o buffer.

       "Nospaceforstripbuffer":
          There was insufficient memory to allocate an i/o buffer.

       "Cannothandleformat":
          The image has a format (combination of BitsPerSample, SamplesPerPixel, and  PhotometricInterpretation)
          that TIFFReadRGBAImage() can not handle.

       "NospaceforB&Wmappingtable":
          There was insufficient memory to allocate a table used to map grayscale data to RGB.

       "NospaceforPalettemappingtable":
          There was insufficient memory to allocate a table used to map data to 8-bit RGB.

       TIFFReadRGBAImage - read and decode an image into a fixed-format raster

       In C++ the stopOnError parameter defaults to 0.

       SamplesPerPixel must be either 1, 2, 4, 8, or 16 bits.  Colorimetric samples/pixel must be either  1,  3,
       or 4 (i.e.  SamplesPerPixel minus ExtraSamples).

       Palettte  image  colormaps that appear to be incorrectly written as 8-bit values are automatically scaled
       to 16-bits.

       IFFReadRGBAImage() is just a wrapper around the more general TIFFRGBAImage facilities.

       1 is returned if the image was successfully read and converted.  Otherwise, 0 is returned if an error was
       encountered and stopOnError is zero.

TIFFOpen  (3tiff),  TIFFRGBAImage  (3tiff),  TIFFReadRGBAStrip (3tiff), TIFFReadRGBATile (3tiff), libtiff
       (3tiff)

          #include <tiffio.h>

       TIFFGetR(abgr)
              ((abgr)&0xff)

       TIFFGetG(abgr)
              (((abgr) >> 8) & 0xff)

       TIFFGetB(abgr)
              (((abgr) >> 16) & 0xff)

       TIFFGetA(abgr)
              (((abgr) >> 24) & 0xff)

       intTIFFReadRGBAImage(TIFF*tif,uint32_twidth,uint32_theight,uint32_t*raster,intstopOnError)intTIFFReadRGBAImageOriented(TIFF*tif,uint32_twidth,uint32_theight,uint32_t*raster,intorientation,intstopOnError)