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1 /*****************************************************************************/
2 // Copyright 2006-2008 Adobe Systems Incorporated
3 // All Rights Reserved.
4 //
5 // NOTICE:  Adobe permits you to use, modify, and distribute this file in
6 // accordance with the terms of the Adobe license agreement accompanying it.
7 /*****************************************************************************/
8 
9 /* $Id: //mondo/dng_sdk_1_4/dng_sdk/source/dng_pixel_buffer.h#1 $ */
10 /* $DateTime: 2012/05/30 13:28:51 $ */
11 /* $Change: 832332 $ */
12 /* $Author: tknoll $ */
13 
14 /** \file
15  * Support for holding buffers of sample data.
16  */
17 
18 /*****************************************************************************/
19 
20 #ifndef __dng_pixel_buffer__
21 #define __dng_pixel_buffer__
22 
23 /*****************************************************************************/
24 
25 #include "dng_assertions.h"
26 #include "dng_rect.h"
27 #include "dng_safe_arithmetic.h"
28 #include "dng_tag_types.h"
29 
30 /*****************************************************************************/
31 
32 /// Compute best set of step values for a given source and destination area and stride.
33 
34 void OptimizeOrder (const void *&sPtr,
35 					void *&dPtr,
36 					uint32 sPixelSize,
37 					uint32 dPixelSize,
38 					uint32 &count0,
39 					uint32 &count1,
40 					uint32 &count2,
41 					int32 &sStep0,
42 					int32 &sStep1,
43 					int32 &sStep2,
44 					int32 &dStep0,
45 					int32 &dStep1,
46 					int32 &dStep2);
47 
48 void OptimizeOrder (const void *&sPtr,
49 					uint32 sPixelSize,
50 					uint32 &count0,
51 					uint32 &count1,
52 					uint32 &count2,
53 					int32 &sStep0,
54 					int32 &sStep1,
55 					int32 &sStep2);
56 
57 void OptimizeOrder (void *&dPtr,
58 					uint32 dPixelSize,
59 					uint32 &count0,
60 					uint32 &count1,
61 					uint32 &count2,
62 					int32 &dStep0,
63 					int32 &dStep1,
64 					int32 &dStep2);
65 
66 /*****************************************************************************/
67 
68 #define qDebugPixelType 0
69 
70 #if qDebugPixelType
71 
72 #define ASSERT_PIXEL_TYPE(typeVal) CheckPixelType (typeVal)
73 
74 #else
75 
76 #define ASSERT_PIXEL_TYPE(typeVal) DNG_ASSERT (fPixelType == typeVal, "Pixel type access mismatch")
77 
78 #endif
79 
80 /*****************************************************************************/
81 
82 /// \brief Holds a buffer of pixel data with "pixel geometry" metadata.
83 ///
84 /// The pixel geometry describes the layout in terms of how many planes, rows and columns
85 /// plus the steps (in bytes) between each column, row and plane.
86 
87 class dng_pixel_buffer
88 	{
89 
90 	public:
91 
92 		// Area this buffer holds.
93 
94 		dng_rect fArea;
95 
96 		// Range of planes this buffer holds.
97 
98 		uint32 fPlane;
99 		uint32 fPlanes;
100 
101 		// Steps between pixels.
102 
103 		int32 fRowStep;
104 		int32 fColStep;
105 		int32 fPlaneStep;
106 
107 		// Basic pixel type (TIFF tag type code).
108 
109 		uint32 fPixelType;
110 
111 		// Size of pixel type in bytes.
112 
113 		uint32 fPixelSize;
114 
115 		// Pointer to buffer's data.
116 
117 		void *fData;
118 
119 		// Do we have write-access to this data?
120 
121 		bool fDirty;
122 
123 	private:
124 
125 		void * InternalPixel (int32 row,
126 							  int32 col,
127 					  	      uint32 plane = 0) const
128 			{
129 
130 			// Ensure pixel to be accessed lies inside valid area.
131 			if (row < fArea.t || row >= fArea.b ||
132 				col < fArea.l || col >= fArea.r ||
133 				plane < fPlane || (plane - fPlane) >= fPlanes)
134 				{
135 				ThrowProgramError ("Out-of-range pixel access");
136 				}
137 
138 			// Compute offset of pixel.
139 			const int64 rowOffset = SafeInt64Mult(fRowStep,
140 				static_cast<int64> (row) - static_cast<int64> (fArea.t));
141 			const int64 colOffset = SafeInt64Mult(fColStep,
142 				static_cast<int64> (col) - static_cast<int64> (fArea.l));
143 			const int64 planeOffset = SafeInt64Mult(fPlaneStep,
144 				static_cast<int64> (plane - fPlane));
145 			const int64 offset = SafeInt64Mult(static_cast<int64>(fPixelSize),
146 				SafeInt64Add(SafeInt64Add(rowOffset, colOffset), planeOffset));
147 
148 			// Add offset to buffer base address.
149 			return static_cast<void *> (static_cast<uint8 *> (fData) + offset);
150 
151 			}
152 
153 		#if qDebugPixelType
154 
155 		void CheckPixelType (uint32 pixelType) const;
156 
157 		#endif
158 
159 	public:
160 
161 		dng_pixel_buffer ();
162 
163 		/// Note: This constructor is for internal use only and should not be
164 		/// considered part of the DNG SDK API.
165 		///
166 		/// Initialize the pixel buffer according to the given parameters (see
167 		/// below). May throw an error if arithmetic overflow occurs when
168 		/// computing the row, column or plane step, or if an invalid value was
169 		/// passed for planarConfiguration.
170 		///
171 		/// \param size Area covered by the pixel buffer
172 		/// \param plane Index of the first plane
173 		/// \param planes Number of planes
174 		/// \param pixelType Pixel data type (one of the values defined in
175 		///        dng_tag_types.h)
176 		/// \param planarConfiguration Layout of the pixel planes in memory: One
177 		///        of pcInterleaved, pcPlanar, or pcRowInterleaved (defined in
178 		///        dng_tag_values.h)
179 		/// \param data Pointer to the pixel data
180 		dng_pixel_buffer (const dng_rect &area, uint32 plane, uint32 planes,
181 						  uint32 pixelType, uint32 planarConfiguration,
182 						  void *data);
183 
184 		dng_pixel_buffer (const dng_pixel_buffer &buffer);
185 
186 		dng_pixel_buffer & operator= (const dng_pixel_buffer &buffer);
187 
188 		virtual ~dng_pixel_buffer ();
189 
190 		/// Get the range of pixel values.
191 		/// \retval Range of value a pixel can take. (Meaning [0, max] for unsigned case. Signed case is biased so [-32768, max - 32768].)
192 
193 		uint32 PixelRange () const;
194 
195 		/// Get extent of pixels in buffer
196 		/// \retval Rectangle giving valid extent of buffer.
197 
Area()198 		const dng_rect & Area () const
199 			{
200 			return fArea;
201 			}
202 
203 		/// Number of planes of image data.
204 		/// \retval Number of planes held in buffer.
205 
Planes()206 		uint32 Planes () const
207 			{
208 			return fPlanes;
209 			}
210 
211 		/// Step, in pixels not bytes, between rows of data in buffer.
212 		/// \retval row step in pixels. May be negative.
213 
RowStep()214 		int32 RowStep () const
215 			{
216 			return fRowStep;
217 			}
218 
219 		/// Step, in pixels not bytes, between planes of data in buffer.
220 		/// \retval plane step in pixels. May be negative.
221 
PlaneStep()222 		int32 PlaneStep () const
223 			{
224 			return fPlaneStep;
225 			}
226 
227 		/// Get read-only untyped (void *) pointer to pixel data starting at a specific pixel in the buffer.
228 		/// \param row Start row for buffer pointer.
229 		/// \param col Start column for buffer pointer.
230 		/// \param plane Start plane for buffer pointer.
231 		/// \retval Pointer to pixel data as void *.
232 
233 		const void * ConstPixel (int32 row,
234 					  			 int32 col,
235 					  			 uint32 plane = 0) const
236 			{
237 
238 			return InternalPixel (row, col, plane);
239 
240 			}
241 
242 		/// Get a writable untyped (void *) pointer to pixel data starting at a specific pixel in the buffer.
243 		/// \param row Start row for buffer pointer.
244 		/// \param col Start column for buffer pointer.
245 		/// \param plane Start plane for buffer pointer.
246 		/// \retval Pointer to pixel data as void *.
247 
248 		void * DirtyPixel (int32 row,
249 					  	   int32 col,
250 					  	   uint32 plane = 0)
251 			{
252 
253 			DNG_ASSERT (fDirty, "Dirty access to const pixel buffer");
254 
255 			return InternalPixel (row, col, plane);
256 
257 			}
258 
259 		/// Get read-only uint8 * to pixel data starting at a specific pixel in the buffer.
260 		/// \param row Start row for buffer pointer.
261 		/// \param col Start column for buffer pointer.
262 		/// \param plane Start plane for buffer pointer.
263 		/// \retval Pointer to pixel data as uint8 *.
264 
265 		const uint8 * ConstPixel_uint8 (int32 row,
266 										int32 col,
267 										uint32 plane = 0) const
268 			{
269 
270 			ASSERT_PIXEL_TYPE (ttByte);
271 
272 			return (const uint8 *) ConstPixel (row, col, plane);
273 
274 			}
275 
276 		/// Get a writable uint8 * to pixel data starting at a specific pixel in the buffer.
277 		/// \param row Start row for buffer pointer.
278 		/// \param col Start column for buffer pointer.
279 		/// \param plane Start plane for buffer pointer.
280 		/// \retval Pointer to pixel data as uint8 *.
281 
282 		uint8 * DirtyPixel_uint8 (int32 row,
283 								  int32 col,
284 								  uint32 plane = 0)
285 			{
286 
287 			ASSERT_PIXEL_TYPE (ttByte);
288 
289 			return (uint8 *) DirtyPixel (row, col, plane);
290 
291 			}
292 
293 		/// Get read-only int8 * to pixel data starting at a specific pixel in the buffer.
294 		/// \param row Start row for buffer pointer.
295 		/// \param col Start column for buffer pointer.
296 		/// \param plane Start plane for buffer pointer.
297 		/// \retval Pointer to pixel data as int8 *.
298 
299 		const int8 * ConstPixel_int8 (int32 row,
300 									  int32 col,
301 									  uint32 plane = 0) const
302 			{
303 
304 			ASSERT_PIXEL_TYPE (ttSByte);
305 
306 			return (const int8 *) ConstPixel (row, col, plane);
307 
308 			}
309 
310 		/// Get a writable int8 * to pixel data starting at a specific pixel in the buffer.
311 		/// \param row Start row for buffer pointer.
312 		/// \param col Start column for buffer pointer.
313 		/// \param plane Start plane for buffer pointer.
314 		/// \retval Pointer to pixel data as int8 *.
315 
316 		int8 * DirtyPixel_int8 (int32 row,
317 								int32 col,
318 								uint32 plane = 0)
319 			{
320 
321 			ASSERT_PIXEL_TYPE (ttSByte);
322 
323 			return (int8 *) DirtyPixel (row, col, plane);
324 
325 			}
326 
327 		/// Get read-only uint16 * to pixel data starting at a specific pixel in the buffer.
328 		/// \param row Start row for buffer pointer.
329 		/// \param col Start column for buffer pointer.
330 		/// \param plane Start plane for buffer pointer.
331 		/// \retval Pointer to pixel data as uint16 *.
332 
333 		const uint16 * ConstPixel_uint16 (int32 row,
334 										  int32 col,
335 										  uint32 plane = 0) const
336 			{
337 
338 			ASSERT_PIXEL_TYPE (ttShort);
339 
340 			return (const uint16 *) ConstPixel (row, col, plane);
341 
342 			}
343 
344 		/// Get a writable uint16 * to pixel data starting at a specific pixel in the buffer.
345 		/// \param row Start row for buffer pointer.
346 		/// \param col Start column for buffer pointer.
347 		/// \param plane Start plane for buffer pointer.
348 		/// \retval Pointer to pixel data as uint16 *.
349 
350 		uint16 * DirtyPixel_uint16 (int32 row,
351 								    int32 col,
352 								    uint32 plane = 0)
353 			{
354 
355 			ASSERT_PIXEL_TYPE (ttShort);
356 
357 			return (uint16 *) DirtyPixel (row, col, plane);
358 
359 			}
360 
361 		/// Get read-only int16 * to pixel data starting at a specific pixel in the buffer.
362 		/// \param row Start row for buffer pointer.
363 		/// \param col Start column for buffer pointer.
364 		/// \param plane Start plane for buffer pointer.
365 		/// \retval Pointer to pixel data as int16 *.
366 
367 		const int16 * ConstPixel_int16 (int32 row,
368 										int32 col,
369 										uint32 plane = 0) const
370 			{
371 
372 			ASSERT_PIXEL_TYPE (ttSShort);
373 
374 			return (const int16 *) ConstPixel (row, col, plane);
375 
376 			}
377 
378 		/// Get a writable int16 * to pixel data starting at a specific pixel in the buffer.
379 		/// \param row Start row for buffer pointer.
380 		/// \param col Start column for buffer pointer.
381 		/// \param plane Start plane for buffer pointer.
382 		/// \retval Pointer to pixel data as int16 *.
383 
384 		int16 * DirtyPixel_int16 (int32 row,
385 								  int32 col,
386 								  uint32 plane = 0)
387 			{
388 
389 			ASSERT_PIXEL_TYPE (ttSShort);
390 
391 			return (int16 *) DirtyPixel (row, col, plane);
392 
393 			}
394 
395 		/// Get read-only uint32 * to pixel data starting at a specific pixel in the buffer.
396 		/// \param row Start row for buffer pointer.
397 		/// \param col Start column for buffer pointer.
398 		/// \param plane Start plane for buffer pointer.
399 		/// \retval Pointer to pixel data as uint32 *.
400 
401 		const uint32 * ConstPixel_uint32 (int32 row,
402 										  int32 col,
403 										  uint32 plane = 0) const
404 			{
405 
406 			ASSERT_PIXEL_TYPE (ttLong);
407 
408 			return (const uint32 *) ConstPixel (row, col, plane);
409 
410 			}
411 
412 		/// Get a writable uint32 * to pixel data starting at a specific pixel in the buffer.
413 		/// \param row Start row for buffer pointer.
414 		/// \param col Start column for buffer pointer.
415 		/// \param plane Start plane for buffer pointer.
416 		/// \retval Pointer to pixel data as uint32 *.
417 
418 		uint32 * DirtyPixel_uint32 (int32 row,
419 								    int32 col,
420 								    uint32 plane = 0)
421 			{
422 
423 			ASSERT_PIXEL_TYPE (ttLong);
424 
425 			return (uint32 *) DirtyPixel (row, col, plane);
426 
427 			}
428 
429 		/// Get read-only int32 * to pixel data starting at a specific pixel in the buffer.
430 		/// \param row Start row for buffer pointer.
431 		/// \param col Start column for buffer pointer.
432 		/// \param plane Start plane for buffer pointer.
433 		/// \retval Pointer to pixel data as int32 *.
434 
435 		const int32 * ConstPixel_int32 (int32 row,
436 										int32 col,
437 										uint32 plane = 0) const
438 			{
439 
440 			ASSERT_PIXEL_TYPE (ttSLong);
441 
442 			return (const int32 *) ConstPixel (row, col, plane);
443 
444 			}
445 
446 		/// Get a writable int32 * to pixel data starting at a specific pixel in the buffer.
447 		/// \param row Start row for buffer pointer.
448 		/// \param col Start column for buffer pointer.
449 		/// \param plane Start plane for buffer pointer.
450 		/// \retval Pointer to pixel data as int32 *.
451 
452 		int32 * DirtyPixel_int32 (int32 row,
453 								  int32 col,
454 								  uint32 plane = 0)
455 			{
456 
457 			ASSERT_PIXEL_TYPE (ttSLong);
458 
459 			return (int32 *) DirtyPixel (row, col, plane);
460 
461 			}
462 
463 		/// Get read-only real32 * to pixel data starting at a specific pixel in the buffer.
464 		/// \param row Start row for buffer pointer.
465 		/// \param col Start column for buffer pointer.
466 		/// \param plane Start plane for buffer pointer.
467 		/// \retval Pointer to pixel data as real32 *.
468 
469 		const real32 * ConstPixel_real32 (int32 row,
470 										  int32 col,
471 										  uint32 plane = 0) const
472 			{
473 
474 			ASSERT_PIXEL_TYPE (ttFloat);
475 
476 			return (const real32 *) ConstPixel (row, col, plane);
477 
478 			}
479 
480 		/// Get a writable real32 * to pixel data starting at a specific pixel in the buffer.
481 		/// \param row Start row for buffer pointer.
482 		/// \param col Start column for buffer pointer.
483 		/// \param plane Start plane for buffer pointer.
484 		/// \retval Pointer to pixel data as real32 *.
485 
486 		real32 * DirtyPixel_real32 (int32 row,
487 									int32 col,
488 									uint32 plane = 0)
489 			{
490 
491 			ASSERT_PIXEL_TYPE (ttFloat);
492 
493 			return (real32 *) DirtyPixel (row, col, plane);
494 
495 			}
496 
497 		/// Initialize a rectangular area of pixel buffer to a constant.
498 		/// \param area Rectangle of pixel buffer to set.
499 		/// \param plane Plane to start filling on.
500 		/// \param planes Number of planes to fill.
501 		/// \param value Constant value to set pixels to.
502 
503 		void SetConstant (const dng_rect &area,
504 					      uint32 plane,
505 					      uint32 planes,
506 					      uint32 value);
507 
508 		/// Initialize a rectangular area of pixel buffer to a constant unsigned 8-bit value.
509 		/// \param area Rectangle of pixel buffer to set.
510 		/// \param plane Plane to start filling on.
511 		/// \param planes Number of planes to fill.
512 		/// \param value Constant uint8 value to set pixels to.
513 
SetConstant_uint8(const dng_rect & area,uint32 plane,uint32 planes,uint8 value)514 		void SetConstant_uint8 (const dng_rect &area,
515 								uint32 plane,
516 								uint32 planes,
517 								uint8 value)
518 			{
519 
520 			DNG_ASSERT (fPixelType == ttByte, "Mismatched pixel type");
521 
522 			SetConstant (area, plane, planes, (uint32) value);
523 
524 			}
525 
526 		/// Initialize a rectangular area of pixel buffer to a constant unsigned 16-bit value.
527 		/// \param area Rectangle of pixel buffer to set.
528 		/// \param plane Plane to start filling on.
529 		/// \param planes Number of planes to fill.
530 		/// \param value Constant uint16 value to set pixels to.
531 
SetConstant_uint16(const dng_rect & area,uint32 plane,uint32 planes,uint16 value)532 		void SetConstant_uint16 (const dng_rect &area,
533 								 uint32 plane,
534 								 uint32 planes,
535 								 uint16 value)
536 			{
537 
538 			DNG_ASSERT (fPixelType == ttShort, "Mismatched pixel type");
539 
540 			SetConstant (area, plane, planes, (uint32) value);
541 
542 			}
543 
544 		/// Initialize a rectangular area of pixel buffer to a constant signed 16-bit value.
545 		/// \param area Rectangle of pixel buffer to set.
546 		/// \param plane Plane to start filling on.
547 		/// \param planes Number of planes to fill.
548 		/// \param value Constant int16 value to set pixels to.
549 
SetConstant_int16(const dng_rect & area,uint32 plane,uint32 planes,int16 value)550 		void SetConstant_int16 (const dng_rect &area,
551 								uint32 plane,
552 								uint32 planes,
553 								int16 value)
554 			{
555 
556 			DNG_ASSERT (fPixelType == ttSShort, "Mismatched pixel type");
557 
558 			SetConstant (area, plane, planes, (uint32) (uint16) value);
559 
560 			}
561 
562 		/// Initialize a rectangular area of pixel buffer to a constant unsigned 32-bit value.
563 		/// \param area Rectangle of pixel buffer to set.
564 		/// \param plane Plane to start filling on.
565 		/// \param planes Number of planes to fill.
566 		/// \param value Constant uint32 value to set pixels to.
567 
SetConstant_uint32(const dng_rect & area,uint32 plane,uint32 planes,uint32 value)568 		void SetConstant_uint32 (const dng_rect &area,
569 								 uint32 plane,
570 								 uint32 planes,
571 								 uint32 value)
572 			{
573 
574 			DNG_ASSERT (fPixelType == ttLong, "Mismatched pixel type");
575 
576 			SetConstant (area, plane, planes, value);
577 
578 			}
579 
580 		/// Initialize a rectangular area of pixel buffer to a constant real 32-bit value.
581 		/// \param area Rectangle of pixel buffer to set.
582 		/// \param plane Plane to start filling on.
583 		/// \param planes Number of planes to fill.
584 		/// \param value Constant real32 value to set pixels to.
585 
SetConstant_real32(const dng_rect & area,uint32 plane,uint32 planes,real32 value)586 		void SetConstant_real32 (const dng_rect &area,
587 								 uint32 plane,
588 								 uint32 planes,
589 								 real32 value)
590 			{
591 
592 			DNG_ASSERT (fPixelType == ttFloat, "Mismatched pixel type");
593 
594 			union
595 				{
596 				uint32 i;
597 				real32 f;
598 				} x;
599 
600 			x.f = value;
601 
602 			SetConstant (area, plane, planes, x.i);
603 
604 			}
605 
606 		/// Initialize a rectangular area of pixel buffer to zeros.
607 		/// \param area Rectangle of pixel buffer to zero.
608 		/// \param area Area to zero
609 		/// \param plane Plane to start filling on.
610 		/// \param planes Number of planes to fill.
611 
612 		void SetZero (const dng_rect &area,
613 					  uint32 plane,
614 					  uint32 planes);
615 
616 		/// Copy image data from an area of one pixel buffer to same area of another.
617 		/// \param src Buffer to copy from.
618 		/// \param area Rectangle of pixel buffer to copy.
619 		/// \param srcPlane Plane to start copy in src.
620 		/// \param dstPlane Plane to start copy in dst.
621 		/// \param planes Number of planes to copy.
622 
623 		void CopyArea (const dng_pixel_buffer &src,
624 					   const dng_rect &area,
625 					   uint32 srcPlane,
626 					   uint32 dstPlane,
627 					   uint32 planes);
628 
629 		/// Copy image data from an area of one pixel buffer to same area of another.
630 		/// \param src Buffer to copy from.
631 		/// \param area Rectangle of pixel buffer to copy.
632 		/// \param plane Plane to start copy in src and this.
633 		/// \param planes Number of planes to copy.
634 
CopyArea(const dng_pixel_buffer & src,const dng_rect & area,uint32 plane,uint32 planes)635 		void CopyArea (const dng_pixel_buffer &src,
636 					   const dng_rect &area,
637 					   uint32 plane,
638 					   uint32 planes)
639 			{
640 
641 			CopyArea (src, area, plane, plane, planes);
642 
643 			}
644 
645 		/// Calculate the offset phase of destination rectangle relative to source rectangle.
646 		/// Phase is based on a 0,0 origin and the notion of repeating srcArea across dstArea.
647 		/// It is the number of pixels into srcArea to start repeating from when tiling dstArea.
648 		/// \retval dng_point containing horizontal and vertical phase.
649 
650 		static dng_point RepeatPhase (const dng_rect &srcArea,
651 					   			   	  const dng_rect &dstArea);
652 
653 		/// Repeat the image data in srcArea across dstArea.
654 		/// (Generally used for padding operations.)
655 		/// \param srcArea Area to repeat from.
656 		/// \param dstArea Area to fill with data from srcArea.
657 
658 		void RepeatArea (const dng_rect &srcArea,
659 						 const dng_rect &dstArea);
660 
661 		/// Replicates a sub-area of a buffer to fill the entire buffer.
662 
663 		void RepeatSubArea (const dng_rect subArea,
664 						    uint32 repeatV = 1,
665 						    uint32 repeatH = 1);
666 
667 		/// Apply a right shift (C++ oerpator >>) to all pixel values. Only implemented for 16-bit (signed or unsigned) pixel buffers.
668 		/// \param shift Number of bits by which to right shift each pixel value.
669 
670 		void ShiftRight (uint32 shift);
671 
672 		/// Change metadata so pixels are iterated in opposite horizontal order.
673 		/// This operation does not require movement of actual pixel data.
674 
675 		void FlipH ();
676 
677 		/// Change metadata so pixels are iterated in opposite vertical order.
678 		/// This operation does not require movement of actual pixel data.
679 
680 		void FlipV ();
681 
682 		/// Change metadata so pixels are iterated in opposite plane order.
683 		/// This operation does not require movement of actual pixel data.
684 
685 		void FlipZ ();	// Flip planes
686 
687 		/// Return true if the contents of an area of the pixel buffer area are the same as those of another.
688 		/// \param rhs Buffer to compare against.
689 		/// \param area Rectangle of pixel buffer to test.
690 		/// \param plane Plane to start comparing.
691 		/// \param planes Number of planes to compare.
692 		/// \retval bool true if areas are equal, false otherwise.
693 
694 		bool EqualArea (const dng_pixel_buffer &rhs,
695 					    const dng_rect &area,
696 					    uint32 plane,
697 					    uint32 planes) const;
698 
699 		/// Return the absolute value of the maximum difference between two pixel buffers. Used for comparison testing with tolerance
700 		/// \param rhs Buffer to compare against.
701 		/// \param area Rectangle of pixel buffer to test.
702 		/// \param plane Plane to start comparing.
703 		/// \param planes Number of planes to compare.
704 		/// \retval larges absolute value difference between the corresponding pixels each buffer across area.
705 
706 		real64 MaximumDifference (const dng_pixel_buffer &rhs,
707 								  const dng_rect &area,
708 								  uint32 plane,
709 								  uint32 planes) const;
710 
711 	};
712 
713 /*****************************************************************************/
714 
715 #endif
716 
717 /*****************************************************************************/
718