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git.saurik.com Git - wxWidgets.git/blob - src/tiff/libtiff/tif_strip.c
4 * Copyright (c) 1991-1997 Sam Leffler
5 * Copyright (c) 1991-1997 Silicon Graphics, Inc.
7 * Permission to use, copy, modify, distribute, and sell this software and
8 * its documentation for any purpose is hereby granted without fee, provided
9 * that (i) the above copyright notices and this permission notice appear in
10 * all copies of the software and related documentation, and (ii) the names of
11 * Sam Leffler and Silicon Graphics may not be used in any advertising or
12 * publicity relating to the software without the specific, prior written
13 * permission of Sam Leffler and Silicon Graphics.
15 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
17 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
19 * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
20 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
21 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
22 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
23 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
30 * Strip-organized Image Support Routines.
35 summarize(TIFF
* tif
, size_t summand1
, size_t summand2
, const char* where
)
38 * XXX: We are using casting to uint32 here, bacause sizeof(size_t)
39 * may be larger than sizeof(uint32) on 64-bit architectures.
41 uint32 bytes
= summand1
+ summand2
;
43 if (bytes
- summand1
!= summand2
) {
44 TIFFErrorExt(tif
->tif_clientdata
, tif
->tif_name
, "Integer overflow in %s", where
);
52 multiply(TIFF
* tif
, size_t nmemb
, size_t elem_size
, const char* where
)
54 uint32 bytes
= nmemb
* elem_size
;
56 if (elem_size
&& bytes
/ elem_size
!= nmemb
) {
57 TIFFErrorExt(tif
->tif_clientdata
, tif
->tif_name
, "Integer overflow in %s", where
);
65 * Compute which strip a (row,sample) value is in.
68 TIFFComputeStrip(TIFF
* tif
, uint32 row
, tsample_t sample
)
70 TIFFDirectory
*td
= &tif
->tif_dir
;
73 strip
= row
/ td
->td_rowsperstrip
;
74 if (td
->td_planarconfig
== PLANARCONFIG_SEPARATE
) {
75 if (sample
>= td
->td_samplesperpixel
) {
76 TIFFErrorExt(tif
->tif_clientdata
, tif
->tif_name
,
77 "%lu: Sample out of range, max %lu",
78 (unsigned long) sample
, (unsigned long) td
->td_samplesperpixel
);
79 return ((tstrip_t
) 0);
81 strip
+= sample
*td
->td_stripsperimage
;
87 * Compute how many strips are in an image.
90 TIFFNumberOfStrips(TIFF
* tif
)
92 TIFFDirectory
*td
= &tif
->tif_dir
;
95 nstrips
= (td
->td_rowsperstrip
== (uint32
) -1 ? 1 :
96 TIFFhowmany(td
->td_imagelength
, td
->td_rowsperstrip
));
97 if (td
->td_planarconfig
== PLANARCONFIG_SEPARATE
)
98 nstrips
= multiply(tif
, nstrips
, td
->td_samplesperpixel
,
99 "TIFFNumberOfStrips");
104 * Compute the # bytes in a variable height, row-aligned strip.
107 TIFFVStripSize(TIFF
* tif
, uint32 nrows
)
109 TIFFDirectory
*td
= &tif
->tif_dir
;
111 if (nrows
== (uint32
) -1)
112 nrows
= td
->td_imagelength
;
113 if (td
->td_planarconfig
== PLANARCONFIG_CONTIG
&&
114 td
->td_photometric
== PHOTOMETRIC_YCBCR
&&
117 * Packed YCbCr data contain one Cb+Cr for every
118 * HorizontalSampling*VerticalSampling Y values.
119 * Must also roundup width and height when calculating
120 * since images that are not a multiple of the
121 * horizontal/vertical subsampling area include
122 * YCbCr data for the extended image.
124 uint16 ycbcrsubsampling
[2];
125 tsize_t w
, scanline
, samplingarea
;
127 TIFFGetField( tif
, TIFFTAG_YCBCRSUBSAMPLING
,
128 ycbcrsubsampling
+ 0,
129 ycbcrsubsampling
+ 1 );
131 samplingarea
= ycbcrsubsampling
[0]*ycbcrsubsampling
[1];
132 if (samplingarea
== 0) {
133 TIFFErrorExt(tif
->tif_clientdata
, tif
->tif_name
,
134 "Invalid YCbCr subsampling");
138 w
= TIFFroundup(td
->td_imagewidth
, ycbcrsubsampling
[0]);
139 scanline
= TIFFhowmany8(multiply(tif
, w
, td
->td_bitspersample
,
141 nrows
= TIFFroundup(nrows
, ycbcrsubsampling
[1]);
142 /* NB: don't need TIFFhowmany here 'cuz everything is rounded */
143 scanline
= multiply(tif
, nrows
, scanline
, "TIFFVStripSize");
145 summarize(tif
, scanline
,
146 multiply(tif
, 2, scanline
/ samplingarea
,
147 "TIFFVStripSize"), "TIFFVStripSize"));
149 return ((tsize_t
) multiply(tif
, nrows
, TIFFScanlineSize(tif
),
155 * Compute the # bytes in a raw strip.
158 TIFFRawStripSize(TIFF
* tif
, tstrip_t strip
)
160 TIFFDirectory
* td
= &tif
->tif_dir
;
161 tsize_t bytecount
= td
->td_stripbytecount
[strip
];
163 if (bytecount
<= 0) {
164 TIFFErrorExt(tif
->tif_clientdata
, tif
->tif_name
,
165 "%lu: Invalid strip byte count, strip %lu",
166 (unsigned long) bytecount
, (unsigned long) strip
);
167 bytecount
= (tsize_t
) -1;
174 * Compute the # bytes in a (row-aligned) strip.
176 * Note that if RowsPerStrip is larger than the
177 * recorded ImageLength, then the strip size is
178 * truncated to reflect the actual space required
182 TIFFStripSize(TIFF
* tif
)
184 TIFFDirectory
* td
= &tif
->tif_dir
;
185 uint32 rps
= td
->td_rowsperstrip
;
186 if (rps
> td
->td_imagelength
)
187 rps
= td
->td_imagelength
;
188 return (TIFFVStripSize(tif
, rps
));
192 * Compute a default strip size based on the image
193 * characteristics and a requested value. If the
194 * request is <1 then we choose a strip size according
195 * to certain heuristics.
198 TIFFDefaultStripSize(TIFF
* tif
, uint32 request
)
200 return (*tif
->tif_defstripsize
)(tif
, request
);
204 _TIFFDefaultStripSize(TIFF
* tif
, uint32 s
)
208 * If RowsPerStrip is unspecified, try to break the
209 * image up into strips that are approximately
210 * STRIP_SIZE_DEFAULT bytes long.
212 tsize_t scanline
= TIFFScanlineSize(tif
);
213 s
= (uint32
)STRIP_SIZE_DEFAULT
/ (scanline
== 0 ? 1 : scanline
);
214 if (s
== 0) /* very wide images */
221 * Return the number of bytes to read/write in a call to
222 * one of the scanline-oriented i/o routines. Note that
223 * this number may be 1/samples-per-pixel if data is
224 * stored as separate planes.
227 TIFFScanlineSize(TIFF
* tif
)
229 TIFFDirectory
*td
= &tif
->tif_dir
;
232 if (td
->td_planarconfig
== PLANARCONFIG_CONTIG
) {
233 if (td
->td_photometric
== PHOTOMETRIC_YCBCR
234 && !isUpSampled(tif
)) {
235 uint16 ycbcrsubsampling
[2];
237 TIFFGetField(tif
, TIFFTAG_YCBCRSUBSAMPLING
,
238 ycbcrsubsampling
+ 0,
239 ycbcrsubsampling
+ 1);
241 if (ycbcrsubsampling
[0] == 0) {
242 TIFFErrorExt(tif
->tif_clientdata
, tif
->tif_name
,
243 "Invalid YCbCr subsampling");
247 scanline
= TIFFroundup(td
->td_imagewidth
,
248 ycbcrsubsampling
[0]);
249 scanline
= TIFFhowmany8(multiply(tif
, scanline
,
250 td
->td_bitspersample
,
251 "TIFFScanlineSize"));
253 summarize(tif
, scanline
,
255 scanline
/ ycbcrsubsampling
[0],
259 scanline
= multiply(tif
, td
->td_imagewidth
,
260 td
->td_samplesperpixel
,
264 scanline
= td
->td_imagewidth
;
265 return ((tsize_t
) TIFFhowmany8(multiply(tif
, scanline
,
266 td
->td_bitspersample
,
267 "TIFFScanlineSize")));
271 * Return the number of bytes required to store a complete
272 * decoded and packed raster scanline (as opposed to the
273 * I/O size returned by TIFFScanlineSize which may be less
274 * if data is store as separate planes).
277 TIFFRasterScanlineSize(TIFF
* tif
)
279 TIFFDirectory
*td
= &tif
->tif_dir
;
282 scanline
= multiply (tif
, td
->td_bitspersample
, td
->td_imagewidth
,
283 "TIFFRasterScanlineSize");
284 if (td
->td_planarconfig
== PLANARCONFIG_CONTIG
) {
285 scanline
= multiply (tif
, scanline
, td
->td_samplesperpixel
,
286 "TIFFRasterScanlineSize");
287 return ((tsize_t
) TIFFhowmany8(scanline
));
289 return ((tsize_t
) multiply (tif
, TIFFhowmany8(scanline
),
290 td
->td_samplesperpixel
,
291 "TIFFRasterScanlineSize"));
294 /* vim: set ts=8 sts=8 sw=8 noet: */