1 /* $Id: tif_strip.c,v 1.17 2006/03/21 16:29:33 dron Exp $ */
2
3 /*
4 * Copyright (c) 1991-1997 Sam Leffler
5 * Copyright (c) 1991-1997 Silicon Graphics, Inc.
6 *
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.
14 *
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.
18 *
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
24 * OF THIS SOFTWARE.
25 */
26
27 /*
28 * TIFF Library.
29 *
30 * Strip-organized Image Support Routines.
31 */
32 #include "tiffiop.h"
33
34 static uint32
summarize(TIFF * tif,size_t summand1,size_t summand2,const char * where)35 summarize(TIFF* tif, size_t summand1, size_t summand2, const char* where)
36 {
37 /*
38 * XXX: We are using casting to uint32 here, bacause sizeof(size_t)
39 * may be larger than sizeof(uint32) on 64-bit architectures.
40 */
41 uint32 bytes = summand1 + summand2;
42
43 if (bytes - summand1 != summand2) {
44 TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "Integer overflow in %s", where);
45 bytes = 0;
46 }
47
48 return (bytes);
49 }
50
51 static uint32
multiply(TIFF * tif,size_t nmemb,size_t elem_size,const char * where)52 multiply(TIFF* tif, size_t nmemb, size_t elem_size, const char* where)
53 {
54 uint32 bytes = nmemb * elem_size;
55
56 if (elem_size && bytes / elem_size != nmemb) {
57 TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "Integer overflow in %s", where);
58 bytes = 0;
59 }
60
61 return (bytes);
62 }
63
64 /*
65 * Compute which strip a (row,sample) value is in.
66 */
67 tstrip_t
TIFFComputeStrip(TIFF * tif,uint32 row,tsample_t sample)68 TIFFComputeStrip(TIFF* tif, uint32 row, tsample_t sample)
69 {
70 TIFFDirectory *td = &tif->tif_dir;
71 tstrip_t strip;
72
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);
80 }
81 strip += sample*td->td_stripsperimage;
82 }
83 return (strip);
84 }
85
86 /*
87 * Compute how many strips are in an image.
88 */
89 tstrip_t
TIFFNumberOfStrips(TIFF * tif)90 TIFFNumberOfStrips(TIFF* tif)
91 {
92 TIFFDirectory *td = &tif->tif_dir;
93 tstrip_t nstrips;
94
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");
100 return (nstrips);
101 }
102
103 /*
104 * Compute the # bytes in a variable height, row-aligned strip.
105 */
106 tsize_t
TIFFVStripSize(TIFF * tif,uint32 nrows)107 TIFFVStripSize(TIFF* tif, uint32 nrows)
108 {
109 TIFFDirectory *td = &tif->tif_dir;
110
111 if (nrows == (uint32) -1)
112 nrows = td->td_imagelength;
113 if (td->td_planarconfig == PLANARCONFIG_CONTIG &&
114 td->td_photometric == PHOTOMETRIC_YCBCR &&
115 !isUpSampled(tif)) {
116 /*
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.
123 */
124 uint16 ycbcrsubsampling[2];
125 tsize_t w, scanline, samplingarea;
126
127 TIFFGetField( tif, TIFFTAG_YCBCRSUBSAMPLING,
128 ycbcrsubsampling + 0,
129 ycbcrsubsampling + 1 );
130
131 samplingarea = ycbcrsubsampling[0]*ycbcrsubsampling[1];
132 if (samplingarea == 0) {
133 TIFFErrorExt(tif->tif_clientdata, tif->tif_name,
134 "Invalid YCbCr subsampling");
135 return 0;
136 }
137
138 w = TIFFroundup(td->td_imagewidth, ycbcrsubsampling[0]);
139 scanline = TIFFhowmany8(multiply(tif, w, td->td_bitspersample,
140 "TIFFVStripSize"));
141 nrows = TIFFroundup(nrows, ycbcrsubsampling[1]);
142 /* NB: don't need TIFFhowmany here 'cuz everything is rounded */
143 scanline = multiply(tif, nrows, scanline, "TIFFVStripSize");
144 return ((tsize_t)
145 summarize(tif, scanline,
146 multiply(tif, 2, scanline / samplingarea,
147 "TIFFVStripSize"), "TIFFVStripSize"));
148 } else
149 return ((tsize_t) multiply(tif, nrows, TIFFScanlineSize(tif),
150 "TIFFVStripSize"));
151 }
152
153
154 /*
155 * Compute the # bytes in a raw strip.
156 */
157 tsize_t
TIFFRawStripSize(TIFF * tif,tstrip_t strip)158 TIFFRawStripSize(TIFF* tif, tstrip_t strip)
159 {
160 TIFFDirectory* td = &tif->tif_dir;
161 tsize_t bytecount = td->td_stripbytecount[strip];
162
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;
168 }
169
170 return bytecount;
171 }
172
173 /*
174 * Compute the # bytes in a (row-aligned) strip.
175 *
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
179 * to hold the strip.
180 */
181 tsize_t
TIFFStripSize(TIFF * tif)182 TIFFStripSize(TIFF* tif)
183 {
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));
189 }
190
191 /*
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.
196 */
197 uint32
TIFFDefaultStripSize(TIFF * tif,uint32 request)198 TIFFDefaultStripSize(TIFF* tif, uint32 request)
199 {
200 return (*tif->tif_defstripsize)(tif, request);
201 }
202
203 uint32
_TIFFDefaultStripSize(TIFF * tif,uint32 s)204 _TIFFDefaultStripSize(TIFF* tif, uint32 s)
205 {
206 if ((int32) s < 1) {
207 /*
208 * If RowsPerStrip is unspecified, try to break the
209 * image up into strips that are approximately
210 * STRIP_SIZE_DEFAULT bytes long.
211 */
212 tsize_t scanline = TIFFScanlineSize(tif);
213 s = (uint32)STRIP_SIZE_DEFAULT / (scanline == 0 ? 1 : scanline);
214 if (s == 0) /* very wide images */
215 s = 1;
216 }
217 return (s);
218 }
219
220 /*
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.
225 */
226 tsize_t
TIFFScanlineSize(TIFF * tif)227 TIFFScanlineSize(TIFF* tif)
228 {
229 TIFFDirectory *td = &tif->tif_dir;
230 tsize_t scanline;
231
232 if (td->td_planarconfig == PLANARCONFIG_CONTIG) {
233 if (td->td_photometric == PHOTOMETRIC_YCBCR
234 && !isUpSampled(tif)) {
235 uint16 ycbcrsubsampling[2];
236
237 TIFFGetField(tif, TIFFTAG_YCBCRSUBSAMPLING,
238 ycbcrsubsampling + 0,
239 ycbcrsubsampling + 1);
240
241 if (ycbcrsubsampling[0] == 0) {
242 TIFFErrorExt(tif->tif_clientdata, tif->tif_name,
243 "Invalid YCbCr subsampling");
244 return 0;
245 }
246
247 scanline = TIFFroundup(td->td_imagewidth,
248 ycbcrsubsampling[0]);
249 scanline = TIFFhowmany8(multiply(tif, scanline,
250 td->td_bitspersample,
251 "TIFFScanlineSize"));
252 return ((tsize_t)
253 summarize(tif, scanline,
254 multiply(tif, 2,
255 scanline / ycbcrsubsampling[0],
256 "TIFFVStripSize"),
257 "TIFFVStripSize"));
258 } else {
259 scanline = multiply(tif, td->td_imagewidth,
260 td->td_samplesperpixel,
261 "TIFFScanlineSize");
262 }
263 } else
264 scanline = td->td_imagewidth;
265 return ((tsize_t) TIFFhowmany8(multiply(tif, scanline,
266 td->td_bitspersample,
267 "TIFFScanlineSize")));
268 }
269
270 /*
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).
275 */
276 tsize_t
TIFFRasterScanlineSize(TIFF * tif)277 TIFFRasterScanlineSize(TIFF* tif)
278 {
279 TIFFDirectory *td = &tif->tif_dir;
280 tsize_t scanline;
281
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));
288 } else
289 return ((tsize_t) multiply (tif, TIFFhowmany8(scanline),
290 td->td_samplesperpixel,
291 "TIFFRasterScanlineSize"));
292 }
293
294 /* vim: set ts=8 sts=8 sw=8 noet: */
295