TIFFWRITESCANLINE(3tiff) LibTIFF TIFFWRITESCANLINE(3tiff)
TIFFWriteScanline - write a scanline to an open TIFF file
#include <tiffio.h>
int TIFFWriteScanline(TIFF *tif, void *buf, uint32_t row, uint16_t
sample)
Write data to a file at the specified row. The sample parameter is
used only if data are organized in separate planes
(PlanarConfiguration = 2). The data are assumed to be uncompressed
and in the native bit- and byte-order of the host machine. The data
written to the file is compressed according to the compression scheme
of the current TIFF directory (see further below). If the current
scanline is past the end of the current subfile, the ImageLength
field is automatically increased to include the scanline (except for
PlanarConfiguration = 2, where the ImageLength cannot be changed once
the first data are written). If the ImageLength is increased, the
StripOffsets and StripByteCounts fields are similarly enlarged to
reflect data written past the previous end of image.
The library writes encoded data using the native machine byte order.
Correctly implemented TIFF readers are expected to do any necessary
byte-swapping to correctly process image data with BitsPerSample
greater than 8. The library attempts to hide bit-ordering differences
between the image and the native machine by converting data from the
native machine order.
In C++ the sample parameter defaults to 0.
Once data are written to a file for the current directory, the values
of certain tags may not be altered; see TIFFSetField() for more
information.
It is not possible to write scanlines to a file that uses a tiled
organization. The routine TIFFIsTiled() can be used to determine if
the file is organized as tiles or strips.
TIFFWriteScanline() returns -1 if it immediately detects an error and
1 for a successful write.
All error messages are directed to the TIFFErrorExtR() routine.
%s: File not open for writing:
The file was opened for reading, not writing.
"Can not write scanlines to a tiled image":
An attempt was made to write a scanline to a tiled image. The
image is assumed to be organized in tiles because the TileWidth
and TileLength tags have been set with TIFFSetField().
"Compression algorithm does not support random access":
Data was written in a non-sequential order to a file that uses a
compression algorithm and that has RowsPerStrip greater than one.
That is, data in the image is to be stored in a compressed form,
and with multiple rows packed into a strip. In this case, the
library does not support random access to the data. The data
should either be written as entire strips, sequentially by rows,
or the value of RowsPerStrip should be set to one.
%s: Must set "ImageWidth" before writing data:
The image's width has not be set before the first write. See
TIFFSetField() for information on how to do this.
%s: Must set "PlanarConfiguration" before writing data:
The organization of data has not be defined before the first
write. See TIFFSetField() for information on how to do this.
Can not change "ImageLength" when using separate planes:
Separate image planes are being used (PlanarConfiguration = 2),
but the number of rows has not been specified before the first
write. The library supports the dynamic growth of an image only
when data are organized in a contiguous manner
(PlanarConfiguration = 1).
"%d: Sample out of range, max %d":
The sample parameter was greater than the value of the
SamplesPerPixel tag.
%s: No space for strip arrays:
There was not enough space for the arrays that hold strip offsets
and byte counts.
Writing subsampled YCbCR data does not work correctly because, for
PlanarConfiguration = 2 the size of a scanline is not calculated on a
per-sample basis, and for PlanarConfiguration = 1 the library does
not pack the block-interleaved samples.
TIFFOpen (3tiff), TIFFWriteEncodedStrip (3tiff), TIFFWriteRawStrip
(3tiff), libtiff (3tiff)
LibTIFF contributors
1988-2025, LibTIFF contributors
4.7 March 7, 2026 TIFFWRITESCANLINE(3tiff)
NAME
TIFFWriteScanline - write a scanline to an open TIFF file
SYNOPSIS
#include <tiffio.h>
int TIFFWriteScanline(TIFF *tif, void *buf, uint32_t row, uint16_t
sample)
DESCRIPTION
Write data to a file at the specified row. The sample parameter is
used only if data are organized in separate planes
(PlanarConfiguration = 2). The data are assumed to be uncompressed
and in the native bit- and byte-order of the host machine. The data
written to the file is compressed according to the compression scheme
of the current TIFF directory (see further below). If the current
scanline is past the end of the current subfile, the ImageLength
field is automatically increased to include the scanline (except for
PlanarConfiguration = 2, where the ImageLength cannot be changed once
the first data are written). If the ImageLength is increased, the
StripOffsets and StripByteCounts fields are similarly enlarged to
reflect data written past the previous end of image.
NOTES
The library writes encoded data using the native machine byte order.
Correctly implemented TIFF readers are expected to do any necessary
byte-swapping to correctly process image data with BitsPerSample
greater than 8. The library attempts to hide bit-ordering differences
between the image and the native machine by converting data from the
native machine order.
In C++ the sample parameter defaults to 0.
Once data are written to a file for the current directory, the values
of certain tags may not be altered; see TIFFSetField() for more
information.
It is not possible to write scanlines to a file that uses a tiled
organization. The routine TIFFIsTiled() can be used to determine if
the file is organized as tiles or strips.
RETURN VALUES
TIFFWriteScanline() returns -1 if it immediately detects an error and
1 for a successful write.
DIAGNOSTICS
All error messages are directed to the TIFFErrorExtR() routine.
%s: File not open for writing:
The file was opened for reading, not writing.
"Can not write scanlines to a tiled image":
An attempt was made to write a scanline to a tiled image. The
image is assumed to be organized in tiles because the TileWidth
and TileLength tags have been set with TIFFSetField().
"Compression algorithm does not support random access":
Data was written in a non-sequential order to a file that uses a
compression algorithm and that has RowsPerStrip greater than one.
That is, data in the image is to be stored in a compressed form,
and with multiple rows packed into a strip. In this case, the
library does not support random access to the data. The data
should either be written as entire strips, sequentially by rows,
or the value of RowsPerStrip should be set to one.
%s: Must set "ImageWidth" before writing data:
The image's width has not be set before the first write. See
TIFFSetField() for information on how to do this.
%s: Must set "PlanarConfiguration" before writing data:
The organization of data has not be defined before the first
write. See TIFFSetField() for information on how to do this.
Can not change "ImageLength" when using separate planes:
Separate image planes are being used (PlanarConfiguration = 2),
but the number of rows has not been specified before the first
write. The library supports the dynamic growth of an image only
when data are organized in a contiguous manner
(PlanarConfiguration = 1).
"%d: Sample out of range, max %d":
The sample parameter was greater than the value of the
SamplesPerPixel tag.
%s: No space for strip arrays:
There was not enough space for the arrays that hold strip offsets
and byte counts.
BUGS
Writing subsampled YCbCR data does not work correctly because, for
PlanarConfiguration = 2 the size of a scanline is not calculated on a
per-sample basis, and for PlanarConfiguration = 1 the library does
not pack the block-interleaved samples.
SEE ALSO
TIFFOpen (3tiff), TIFFWriteEncodedStrip (3tiff), TIFFWriteRawStrip
(3tiff), libtiff (3tiff)
AUTHOR
LibTIFF contributors
COPYRIGHT
1988-2025, LibTIFF contributors
4.7 March 7, 2026 TIFFWRITESCANLINE(3tiff)