TIFFREADRGBASTRIP(3tiff) LibTIFF TIFFREADRGBASTRIP(3tiff)
NAME
TIFFReadRGBAStrip - read and decode an image strip into a fixed-format
raster
SYNOPSIS
#include <tiffio.h>
TIFFReadRGBAStrip(3) *tif, uint32_t row, uint32_t *raster)
int TIFFReadRGBAStripExt(TIFF *tif, uint32_t row, uint32_t *raster, int
stop_on_error)
DESCRIPTION
TIFFReadRGBAStrip() reads a single strip of a strip-based image into
memory, storing the result in the user supplied RGBA raster. The
raster is assumed to be an array of ImageWidth x RowsPerStrip 32-bit
entries, where ImageWidth is the width of the image
(TIFFTAG_IMAGEWIDTH) and RowsPerStrip is the maximum lines in a strip
(TIFFTAG_ROWSPERSTRIP).
TIFFReadRGBAStripExt() provides the paramater stop_on_error. Its
behaviour is described at TIFFReadRGBAImage.
The row value should be the row of the first row in the strip (strip x
RowsPerStrip, zero based).
Note that the raster is assume to be organized such that the pixel at
location (x, y) is raster [ y x width + x ]; with the raster origin in
the lower-left hand corner of the strip. That is bottom to top
organization. When reading a partial last strip in the file the last
line of the image will begin at the beginning of the buffer.
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).
See the TIFFRGBAImage page for more details on how various image types
are converted to RGBA values.
NOTES
Samples must be either 1, 2, 4, 8, or 16 bits. Colorimetric
samples/pixel must be either 1, 3, or 4 (i.e. SamplesPerPixel -
ExtraSamples).
Palette image colormaps that appear to be incorrectly written as 8-bit
values are automatically scaled to 16-bits.
TIFFReadRGBAStrip() is just a wrapper around the more general
TIFFRGBAImage facilities. It's main advantage over the similar
TIFFReadRGBAImage() function is that for large images a single buffer
capable of holding the whole image doesn't need to be allocated, only
enough for one strip. The TIFFReadRGBATile() function does a similar
operation for tiled images.
RETURN VALUES
1 is returned if the image was successfully read and converted.
Otherwise, 0 is returned if an error was encountered.
DIAGNOSTICS
All error messages are directed to the TIFFErrorExtR() routine.
"Sorry, can not handle %d-bit pictures":
The image had BitsPerSample other than 1, 2, 4, 8, or 16.
"Sorry, can not handle %d-channel images":
The image had SamplesPerPixel other than 1, 3, or 4.
Missing needed "PhotometricInterpretation" tag:
The image did not have a tag that describes how to display the data.
No "PhotometricInterpretation" tag, assuming RGB:
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, assuming min-is-black\fP:
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.
"No space for photometric conversion table":
There was insufficient memory for a table used to convert image
samples to 8-bit RGB.
Missing required "Colormap" tag:
A Palette image did not have a required Colormap tag.
"No space for tile buffer":
There was insufficient memory to allocate an i/o buffer.
"No space for strip buffer":
There was insufficient memory to allocate an i/o buffer.
"Can not handle format":
The image has a format (combination of BitsPerSample,
SamplesPerPixel, and PhotometricInterpretation) that
TIFFReadRGBAImage() can not handle.
"No space for B&W mapping table":
There was insufficient memory to allocate a table used to map
grayscale data to RGB.
"No space for Palette mapping table":
There was insufficient memory to allocate a table used to map data
to 8-bit RGB.
SEE ALSO
TIFFOpen(3), TIFFRGBAImage(3), TIFFReadRGBAImage(3),
TIFFReadRGBATile(3), libtiff(3)
AUTHOR
LibTIFF contributors
COPYRIGHT
1988-2022, LibTIFF contributors
4.6 October 9, 2023 TIFFREADRGBASTRIP(3tiff)
tiff 4.6.0 - Generated Thu Oct 12 07:31:03 CDT 2023