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diff --git a/tiff/man/TIFFReadRGBATile.3tiff b/tiff/man/TIFFReadRGBATile.3tiff new file mode 100755 index 0000000..dfae1a9 --- /dev/null +++ b/tiff/man/TIFFReadRGBATile.3tiff @@ -0,0 +1,171 @@ +.\" $Id: TIFFReadRGBATile.3tiff,v 1.2 2005-11-02 11:07:18 dron Exp $ +.\" +.\" Copyright (c) 1991-1997 Sam Leffler +.\" Copyright (c) 1991-1997 Silicon Graphics, Inc. +.\" +.\" Permission to use, copy, modify, distribute, and sell this software and +.\" its documentation for any purpose is hereby granted without fee, provided +.\" that (i) the above copyright notices and this permission notice appear in +.\" all copies of the software and related documentation, and (ii) the names of +.\" Sam Leffler and Silicon Graphics may not be used in any advertising or +.\" publicity relating to the software without the specific, prior written +.\" permission of Sam Leffler and Silicon Graphics. +.\" +.\" THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, +.\" EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY +.\" WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. +.\" +.\" IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR +.\" ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, +.\" OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, +.\" WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF +.\" LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE +.\" OF THIS SOFTWARE. +.\" +.if n .po 0 +.TH TIFFReadRGBATile 3TIFF "December 10, 1998" "libtiff" +.SH NAME +TIFFReadRGBATile \- read and decode an image tile into a fixed-format raster +.SH SYNOPSIS +.B "#include <tiffio.h>" +.sp +.B "#define TIFFGetR(abgr) ((abgr) & 0xff)" +.br +.B "#define TIFFGetG(abgr) (((abgr) >> 8) & 0xff)" +.br +.B "#define TIFFGetB(abgr) (((abgr) >> 16) & 0xff)" +.br +.B "#define TIFFGetA(abgr) (((abgr) >> 24) & 0xff)" +.sp +.BI "int TIFFReadRGBATile(TIFF *" tif ", uint32 " x ", uint32 " y ", uint32 *" raster ")" +.SH DESCRIPTION +.IR TIFFReadRGBATile +reads a single tile of a tile-based image into memory, storing the result in +the user supplied RGBA +.IR raster . +The raster is assumed to be an array of width times length 32-bit entries, +where width is the width of a tile (TIFFTAG_TILEWIDTH) and length is the +height of a tile (TIFFTAG_TILELENGTH). + +.PP +The +.IR x +and +.IR y +values are the offsets from the top left corner to the top left corner of the +tile to be read. They must be an exact multiple of the tile width and length. + +.PP +Note that the raster is assume to be organized such that the pixel at location +(\fIx\fP,\fIy\fP) is \fIraster\fP[\fIy\fP*\fIwidth\fP+\fIx\fP]; with the +raster origin in the +.I lower-left hand corner +of the tile. That is bottom to top organization. Edge tiles which partly fall +off the image will be filled out with appropriate zeroed areas. + +.PP +Raster pixels are 8-bit packed red, green, blue, alpha samples. The macros +.IR TIFFGetR , +.IR TIFFGetG , +.IR TIFFGetB , +and +.I TIFFGetA +should be used to access individual samples. Images without Associated Alpha +matting information have a constant Alpha of 1.0 (255). +.PP +See the +.IR TIFFRGBAImage (3TIFF) +page for more details on how various image types are converted to RGBA values. +.SH NOTES +Samples must be either 1, 2, 4, 8, or 16 bits. Colorimetric samples/pixel must +be either 1, 3, or 4 (i.e. +.I SamplesPerPixel +minus +.IR ExtraSamples ). +.PP +Palette image colormaps that appear to be incorrectly written as 8-bit values +are automatically scaled to 16-bits. +.PP +.I TIFFReadRGBATile +is just a wrapper around the more general +.IR TIFFRGBAImage (3TIFF) +facilities. It's main advantage over the similar +.IR 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 tile. The +.IR TIFFReadRGBAStrip() +function does a similar operation for stripped images. +.SH "RETURN VALUES" +1 is returned if the image was successfully read and converted. +Otherwise, 0 is returned if an error was encountered. +.SH DIAGNOSTICS +All error messages are directed to the +.IR TIFFError (3TIFF) +routine. +.PP +.BR "Sorry, can not handle %d-bit pictures" . +The image had +.I BitsPerSample +other than 1, 2, 4, 8, or 16. +.PP +.BR "Sorry, can not handle %d-channel images" . +The image had +.I SamplesPerPixel +other than 1, 3, or 4. +.PP +\fBMissing needed "PhotometricInterpretation" tag\fP. +The image did not have a tag that describes how to display the data. +.PP +\fBNo "PhotometricInterpretation" tag, assuming RGB\fP. +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 +.SM RGB. +.PP +\fBNo "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. +.PP +.BR "No space for photometric conversion table" . +There was insufficient memory for a table used to convert +image samples to 8-bit +.SM RGB. +.PP +\fBMissing required "Colormap" tag\fP. +A Palette image did not have a required +.I Colormap +tag. +.PP +.BR "No space for tile buffer" . +There was insufficient memory to allocate an i/o buffer. +.PP +.BR "No space for strip buffer" . +There was insufficient memory to allocate an i/o buffer. +.PP +.BR "Can not handle format" . +The image has a format (combination of +.IR BitsPerSample , +.IR SamplesPerPixel , +and +.IR PhotometricInterpretation ) +that +.I TIFFReadRGBAImage +can not handle. +.PP +.BR "No space for B&W mapping table" . +There was insufficient memory to allocate a table used to map +grayscale data to +.SM RGB. +.PP +.BR "No space for Palette mapping table" . +There was insufficient memory to allocate a table used to map data to 8-bit +.SM RGB. +.SH "SEE ALSO" +.BR TIFFOpen (3TIFF), +.BR TIFFRGBAImage (3TIFF), +.BR TIFFReadRGBAImage (3TIFF), +.BR TIFFReadRGBAStrip (3TIFF), +.BR libtiff (3TIFF) +.PP +Libtiff library home page: +.BR http://www.remotesensing.org/libtiff/ |