| CWaveletTransform(3) | libpgf | CWaveletTransform(3) |
NAME¶
CWaveletTransform - PGF wavelet transform.
SYNOPSIS¶
#include <WaveletTransform.h>
Public Member Functions¶
CWaveletTransform (UINT32 width, UINT32 height, int levels,
DataT *data=nullptr)
~CWaveletTransform ()
Destructor. OSError ForwardTransform (int level, int quant)
OSError InverseTransform (int level, UINT32 *width, UINT32 *height,
DataT **data)
CSubband * GetSubband (int level, Orientation
orientation)
Private Member Functions¶
void Destroy ()
void InitSubbands (UINT32 width, UINT32 height, DataT *data)
void ForwardRow (DataT *buff, UINT32 width)
void InverseRow (DataT *buff, UINT32 width)
void InterleavedToSubbands (int destLevel, DataT *loRow,
DataT *hiRow, UINT32 width)
void SubbandsToInterleaved (int srcLevel, DataT *loRow,
DataT *hiRow, UINT32 width)
Private Attributes¶
int m_nLevels
number of LL levels: one more than header.nLevels in PGFimage
CSubband(* m_subband )[NSubbands]
quadtree of subbands: LL HL LH HH
Friends¶
class CSubband
Detailed Description¶
PGF wavelet transform.
PGF wavelet transform class.
Author:
C. Stamm, R. Spuler
Definition at line 55 of file WaveletTransform.h.
Constructor & Destructor Documentation¶
CWaveletTransform::CWaveletTransform (UINT32 width, UINT32 height, int levels, DataT * data = nullptr)¶
Constructor: Constructs a wavelet transform pyramid of given size and levels.
Parameters:
width The width of the original image (at level 0)
in pixels
height The height of the original image (at level 0) in pixels
levels The number of levels (>= 0)
data Input data of subband LL at level 0
height The height of the original image (at level 0) in pixels
levels The number of levels (>= 0)
data Input data of subband LL at level 0
Definition at line 40 of file WaveletTransform.cpp.
41 : m_nLevels(levels + 1) // m_nLevels in CPGFImage determines the number of FWT steps; this.m_nLevels determines the number subband-planes
42 , m_subband(nullptr)
43 #ifdef __PGFROISUPPORT__
44 , m_indices(nullptr)
45 #endif
46 {
47 ASSERT(m_nLevels > 0 && m_nLevels <= MaxLevel + 1);
48 InitSubbands(width, height, data);
49 }
CWaveletTransform::~CWaveletTransform () [inline]¶
Destructor.
Definition at line 69 of file WaveletTransform.h.
69 { Destroy(); }
Member Function Documentation¶
void CWaveletTransform::Destroy () [inline], [private]¶
Definition at line 125 of file WaveletTransform.h.
125 {
126 delete[] m_subband; m_subband = nullptr;
127 #ifdef __PGFROISUPPORT__
128 delete[] m_indices; m_indices = nullptr;
129 #endif
130 }
void CWaveletTransform::ForwardRow (DataT * buff, UINT32 width) [private]¶
Definition at line 180 of file WaveletTransform.cpp.
180 {
181 if (width >= FilterSize) {
182 UINT32 i = 3;
183
184 // left border handling
185 src[1] -= ((src[0] + src[2] + c1) >> 1); // high pass
186 src[0] += ((src[1] + c1) >> 1); // low pass
187
188 // middle part
189 for (; i < width-1; i += 2) {
190 src[i] -= ((src[i-1] + src[i+1] + c1) >> 1); // high pass
191 src[i-1] += ((src[i-2] + src[i] + c2) >> 2); // low pass
192 }
193
194 // right border handling
195 if (width & 1) {
196 src[i-1] += ((src[i-2] + c1) >> 1); // low pass
197 } else {
198 src[i] -= src[i-1]; // high pass
199 src[i-1] += ((src[i-2] + src[i] + c2) >> 2); // low pass
200 }
201 }
202 }
OSError CWaveletTransform::ForwardTransform (int level, int quant)¶
Compute fast forward wavelet transform of LL subband at given level and stores result in all 4 subbands of level + 1.
Parameters:
level A wavelet transform pyramid level (>= 0
&& < Levels())
quant A quantization value (linear scalar quantization)
quant A quantization value (linear scalar quantization)
Returns:
error in case of a memory allocation problem
Definition at line 88 of file WaveletTransform.cpp.
88 {
89 ASSERT(level >= 0 && level < m_nLevels - 1);
90 const int destLevel = level + 1;
91 ASSERT(m_subband[destLevel]);
92 CSubband* srcBand = &m_subband[level][LL]; ASSERT(srcBand);
93 const UINT32 width = srcBand->GetWidth();
94 const UINT32 height = srcBand->GetHeight();
95 DataT* src = srcBand->GetBuffer(); ASSERT(src);
96 DataT *row0, *row1, *row2, *row3;
97
98 // Allocate memory for next transform level
99 for (int i=0; i < NSubbands; i++) {
100 if (!m_subband[destLevel][i].AllocMemory()) return InsufficientMemory;
101 }
102
103 if (height >= FilterSize) { // changed from FilterSizeH to FilterSize
104 // top border handling
105 row0 = src; row1 = row0 + width; row2 = row1 + width;
106 ForwardRow(row0, width);
107 ForwardRow(row1, width);
108 ForwardRow(row2, width);
109 for (UINT32 k=0; k < width; k++) {
110 row1[k] -= ((row0[k] + row2[k] + c1) >> 1); // high pass
111 row0[k] += ((row1[k] + c1) >> 1); // low pass
112 }
113 InterleavedToSubbands(destLevel, row0, row1, width);
114 row0 = row1; row1 = row2; row2 += width; row3 = row2 + width;
115
116 // middle part
117 for (UINT32 i=3; i < height-1; i += 2) {
118 ForwardRow(row2, width);
119 ForwardRow(row3, width);
120 for (UINT32 k=0; k < width; k++) {
121 row2[k] -= ((row1[k] + row3[k] + c1) >> 1); // high pass filter
122 row1[k] += ((row0[k] + row2[k] + c2) >> 2); // low pass filter
123 }
124 InterleavedToSubbands(destLevel, row1, row2, width);
125 row0 = row2; row1 = row3; row2 = row3 + width; row3 = row2 + width;
126 }
127
128 // bottom border handling
129 if (height & 1) {
130 for (UINT32 k=0; k < width; k++) {
131 row1[k] += ((row0[k] + c1) >> 1); // low pass
132 }
133 InterleavedToSubbands(destLevel, row1, nullptr, width);
134 row0 = row1; row1 += width;
135 } else {
136 ForwardRow(row2, width);
137 for (UINT32 k=0; k < width; k++) {
138 row2[k] -= row1[k]; // high pass
139 row1[k] += ((row0[k] + row2[k] + c2) >> 2); // low pass
140 }
141 InterleavedToSubbands(destLevel, row1, row2, width);
142 row0 = row1; row1 = row2; row2 += width;
143 }
144 } else {
145 // if height is too small
146 row0 = src; row1 = row0 + width;
147 // first part
148 for (UINT32 k=0; k < height; k += 2) {
149 ForwardRow(row0, width);
150 ForwardRow(row1, width);
151 InterleavedToSubbands(destLevel, row0, row1, width);
152 row0 += width << 1; row1 += width << 1;
153 }
154 // bottom
155 if (height & 1) {
156 InterleavedToSubbands(destLevel, row0, nullptr, width);
157 }
158 }
159
160 if (quant > 0) {
161 // subband quantization (without LL)
162 for (int i=1; i < NSubbands; i++) {
163 m_subband[destLevel][i].Quantize(quant);
164 }
165 // LL subband quantization
166 if (destLevel == m_nLevels - 1) {
167 m_subband[destLevel][LL].Quantize(quant);
168 }
169 }
170
171 // free source band
172 srcBand->FreeMemory();
173 return NoError;
174 }
CSubband* CWaveletTransform::GetSubband (int level, Orientation orientation) [inline]¶
Get pointer to one of the 4 subband at a given level.
Parameters:
level A wavelet transform pyramid level (>= 0
&& <= Levels())
orientation A quarter of the subband (LL, LH, HL, HH)
orientation A quarter of the subband (LL, LH, HL, HH)
Definition at line 93 of file WaveletTransform.h.
93 {
94 ASSERT(level >= 0 && level < m_nLevels);
95 return &m_subband[level][orientation];
96 }
void CWaveletTransform::InitSubbands (UINT32 width, UINT32 height, DataT * data) [private]¶
Definition at line 53 of file WaveletTransform.cpp.
53 {
54 if (m_subband) Destroy();
55
56 // create subbands
57 m_subband = new CSubband[m_nLevels][NSubbands];
58
59 // init subbands
60 UINT32 loWidth = width;
61 UINT32 hiWidth = width;
62 UINT32 loHeight = height;
63 UINT32 hiHeight = height;
64
65 for (int level = 0; level < m_nLevels; level++) {
66 m_subband[level][LL].Initialize(loWidth, loHeight, level, LL); // LL
67 m_subband[level][HL].Initialize(hiWidth, loHeight, level, HL); // HL
68 m_subband[level][LH].Initialize(loWidth, hiHeight, level, LH); // LH
69 m_subband[level][HH].Initialize(hiWidth, hiHeight, level, HH); // HH
70 hiWidth = loWidth >> 1; hiHeight = loHeight >> 1;
71 loWidth = (loWidth + 1) >> 1; loHeight = (loHeight + 1) >> 1;
72 }
73 if (data) {
74 m_subband[0][LL].SetBuffer(data);
75 }
76 }
void CWaveletTransform::InterleavedToSubbands (int destLevel, DataT * loRow, DataT * hiRow, UINT32 width) [private]¶
Definition at line 206 of file WaveletTransform.cpp.
206 {
207 const UINT32 wquot = width >> 1;
208 const bool wrem = (width & 1);
209 CSubband &ll = m_subband[destLevel][LL], &hl = m_subband[destLevel][HL];
210 CSubband &lh = m_subband[destLevel][LH], &hh = m_subband[destLevel][HH];
211
212 if (hiRow) {
213 for (UINT32 i=0; i < wquot; i++) {
214 ll.WriteBuffer(*loRow++); // first access, than increment
215 hl.WriteBuffer(*loRow++);
216 lh.WriteBuffer(*hiRow++); // first access, than increment
217 hh.WriteBuffer(*hiRow++);
218 }
219 if (wrem) {
220 ll.WriteBuffer(*loRow);
221 lh.WriteBuffer(*hiRow);
222 }
223 } else {
224 for (UINT32 i=0; i < wquot; i++) {
225 ll.WriteBuffer(*loRow++); // first access, than increment
226 hl.WriteBuffer(*loRow++);
227 }
228 if (wrem) ll.WriteBuffer(*loRow);
229 }
230 }
void CWaveletTransform::InverseRow (DataT * buff, UINT32 width) [private]¶
Definition at line 419 of file WaveletTransform.cpp.
419 {
420 if (width >= FilterSize) {
421 UINT32 i = 2;
422
423 // left border handling
424 dest[0] -= ((dest[1] + c1) >> 1); // even
425
426 // middle part
427 for (; i < width - 1; i += 2) {
428 dest[i] -= ((dest[i-1] + dest[i+1] + c2) >> 2); // even
429 dest[i-1] += ((dest[i-2] + dest[i] + c1) >> 1); // odd
430 }
431
432 // right border handling
433 if (width & 1) {
434 dest[i] -= ((dest[i-1] + c1) >> 1); // even
435 dest[i-1] += ((dest[i-2] + dest[i] + c1) >> 1); // odd
436 } else {
437 dest[i-1] += dest[i-2]; // odd
438 }
439 }
440 }
OSError CWaveletTransform::InverseTransform (int level, UINT32 * width, UINT32 * height, DataT ** data)¶
Compute fast inverse wavelet transform of all 4 subbands of given level and stores result in LL subband of level - 1.
Parameters:
level A wavelet transform pyramid level (> 0
&& <= Levels())
width A pointer to the returned width of subband LL (in pixels)
height A pointer to the returned height of subband LL (in pixels)
data A pointer to the returned array of image data
width A pointer to the returned width of subband LL (in pixels)
height A pointer to the returned height of subband LL (in pixels)
data A pointer to the returned array of image data
Returns:
error in case of a memory allocation problem
Definition at line 245 of file WaveletTransform.cpp.
245 {
246 ASSERT(srcLevel > 0 && srcLevel < m_nLevels);
247 const int destLevel = srcLevel - 1;
248 ASSERT(m_subband[destLevel]);
249 CSubband* destBand = &m_subband[destLevel][LL];
250 UINT32 width, height;
251
252 // allocate memory for the results of the inverse transform
253 if (!destBand->AllocMemory()) return InsufficientMemory;
254 DataT *origin = destBand->GetBuffer(), *row0, *row1, *row2, *row3;
255
256 #ifdef __PGFROISUPPORT__
257 PGFRect destROI = destBand->GetAlignedROI();
258 const UINT32 destWidth = destROI.Width(); // destination buffer width
259 const UINT32 destHeight = destROI.Height(); // destination buffer height
260 width = destWidth; // destination working width
261 height = destHeight; // destination working height
262
263 // update destination ROI
264 if (destROI.top & 1) {
265 destROI.top++;
266 origin += destWidth;
267 height--;
268 }
269 if (destROI.left & 1) {
270 destROI.left++;
271 origin++;
272 width--;
273 }
274
275 // init source buffer position
276 const UINT32 leftD = destROI.left >> 1;
277 const UINT32 left0 = m_subband[srcLevel][LL].GetAlignedROI().left;
278 const UINT32 left1 = m_subband[srcLevel][HL].GetAlignedROI().left;
279 const UINT32 topD = destROI.top >> 1;
280 const UINT32 top0 = m_subband[srcLevel][LL].GetAlignedROI().top;
281 const UINT32 top1 = m_subband[srcLevel][LH].GetAlignedROI().top;
282 ASSERT(m_subband[srcLevel][LH].GetAlignedROI().left == left0);
283 ASSERT(m_subband[srcLevel][HH].GetAlignedROI().left == left1);
284 ASSERT(m_subband[srcLevel][HL].GetAlignedROI().top == top0);
285 ASSERT(m_subband[srcLevel][HH].GetAlignedROI().top == top1);
286
287 UINT32 srcOffsetX[2] = { 0, 0 };
288 UINT32 srcOffsetY[2] = { 0, 0 };
289
290 if (leftD >= __max(left0, left1)) {
291 srcOffsetX[0] = leftD - left0;
292 srcOffsetX[1] = leftD - left1;
293 } else {
294 if (left0 <= left1) {
295 const UINT32 dx = (left1 - leftD) << 1;
296 destROI.left += dx;
297 origin += dx;
298 width -= dx;
299 srcOffsetX[0] = left1 - left0;
300 } else {
301 const UINT32 dx = (left0 - leftD) << 1;
302 destROI.left += dx;
303 origin += dx;
304 width -= dx;
305 srcOffsetX[1] = left0 - left1;
306 }
307 }
308 if (topD >= __max(top0, top1)) {
309 srcOffsetY[0] = topD - top0;
310 srcOffsetY[1] = topD - top1;
311 } else {
312 if (top0 <= top1) {
313 const UINT32 dy = (top1 - topD) << 1;
314 destROI.top += dy;
315 origin += dy*destWidth;
316 height -= dy;
317 srcOffsetY[0] = top1 - top0;
318 } else {
319 const UINT32 dy = (top0 - topD) << 1;
320 destROI.top += dy;
321 origin += dy*destWidth;
322 height -= dy;
323 srcOffsetY[1] = top0 - top1;
324 }
325 }
326
327 m_subband[srcLevel][LL].InitBuffPos(srcOffsetX[0], srcOffsetY[0]);
328 m_subband[srcLevel][HL].InitBuffPos(srcOffsetX[1], srcOffsetY[0]);
329 m_subband[srcLevel][LH].InitBuffPos(srcOffsetX[0], srcOffsetY[1]);
330 m_subband[srcLevel][HH].InitBuffPos(srcOffsetX[1], srcOffsetY[1]);
331
332 #else
333 width = destBand->GetWidth();
334 height = destBand->GetHeight();
335 PGFRect destROI(0, 0, width, height);
336 const UINT32 destWidth = width; // destination buffer width
337 const UINT32 destHeight = height; // destination buffer height
338
339 // init source buffer position
340 for (int i = 0; i < NSubbands; i++) {
341 m_subband[srcLevel][i].InitBuffPos();
342 }
343 #endif
344
345 if (destHeight >= FilterSize) { // changed from FilterSizeH to FilterSize
346 // top border handling
347 row0 = origin; row1 = row0 + destWidth;
348 SubbandsToInterleaved(srcLevel, row0, row1, width);
349 for (UINT32 k = 0; k < width; k++) {
350 row0[k] -= ((row1[k] + c1) >> 1); // even
351 }
352
353 // middle part
354 row2 = row1 + destWidth; row3 = row2 + destWidth;
355 for (UINT32 i = destROI.top + 2; i < destROI.bottom - 1; i += 2) {
356 SubbandsToInterleaved(srcLevel, row2, row3, width);
357 for (UINT32 k = 0; k < width; k++) {
358 row2[k] -= ((row1[k] + row3[k] + c2) >> 2); // even
359 row1[k] += ((row0[k] + row2[k] + c1) >> 1); // odd
360 }
361 InverseRow(row0, width);
362 InverseRow(row1, width);
363 row0 = row2; row1 = row3; row2 = row1 + destWidth; row3 = row2 + destWidth;
364 }
365
366 // bottom border handling
367 if (height & 1) {
368 SubbandsToInterleaved(srcLevel, row2, nullptr, width);
369 for (UINT32 k = 0; k < width; k++) {
370 row2[k] -= ((row1[k] + c1) >> 1); // even
371 row1[k] += ((row0[k] + row2[k] + c1) >> 1); // odd
372 }
373 InverseRow(row0, width);
374 InverseRow(row1, width);
375 InverseRow(row2, width);
376 row0 = row1; row1 = row2; row2 += destWidth;
377 } else {
378 for (UINT32 k = 0; k < width; k++) {
379 row1[k] += row0[k];
380 }
381 InverseRow(row0, width);
382 InverseRow(row1, width);
383 row0 = row1; row1 += destWidth;
384 }
385 } else {
386 // height is too small
387 row0 = origin; row1 = row0 + destWidth;
388 // first part
389 for (UINT32 k = 0; k < height; k += 2) {
390 SubbandsToInterleaved(srcLevel, row0, row1, width);
391 InverseRow(row0, width);
392 InverseRow(row1, width);
393 row0 += destWidth << 1; row1 += destWidth << 1;
394 }
395 // bottom
396 if (height & 1) {
397 SubbandsToInterleaved(srcLevel, row0, nullptr, width);
398 InverseRow(row0, width);
399 }
400 }
401
402 // free memory of the current srcLevel
403 for (int i = 0; i < NSubbands; i++) {
404 m_subband[srcLevel][i].FreeMemory();
405 }
406
407 // return info
408 *w = destWidth;
409 *h = destHeight;
410 *data = destBand->GetBuffer();
411 return NoError;
412 }
void CWaveletTransform::SubbandsToInterleaved (int srcLevel, DataT * loRow, DataT * hiRow, UINT32 width) [private]¶
Definition at line 444 of file WaveletTransform.cpp.
444 {
445 const UINT32 wquot = width >> 1;
446 const bool wrem = (width & 1);
447 CSubband &ll = m_subband[srcLevel][LL], &hl = m_subband[srcLevel][HL];
448 CSubband &lh = m_subband[srcLevel][LH], &hh = m_subband[srcLevel][HH];
449
450 if (hiRow) {
451 #ifdef __PGFROISUPPORT__
452 const bool storePos = wquot < ll.BufferWidth();
453 UINT32 llPos = 0, hlPos = 0, lhPos = 0, hhPos = 0;
454
455 if (storePos) {
456 // save current src buffer positions
457 llPos = ll.GetBuffPos();
458 hlPos = hl.GetBuffPos();
459 lhPos = lh.GetBuffPos();
460 hhPos = hh.GetBuffPos();
461 }
462 #endif
463
464 for (UINT32 i=0; i < wquot; i++) {
465 *loRow++ = ll.ReadBuffer();// first access, than increment
466 *loRow++ = hl.ReadBuffer();// first access, than increment
467 *hiRow++ = lh.ReadBuffer();// first access, than increment
468 *hiRow++ = hh.ReadBuffer();// first access, than increment
469 }
470
471 if (wrem) {
472 *loRow++ = ll.ReadBuffer();// first access, than increment
473 *hiRow++ = lh.ReadBuffer();// first access, than increment
474 }
475
476 #ifdef __PGFROISUPPORT__
477 if (storePos) {
478 // increment src buffer positions
479 ll.IncBuffRow(llPos);
480 hl.IncBuffRow(hlPos);
481 lh.IncBuffRow(lhPos);
482 hh.IncBuffRow(hhPos);
483 }
484 #endif
485
486 } else {
487 #ifdef __PGFROISUPPORT__
488 const bool storePos = wquot < ll.BufferWidth();
489 UINT32 llPos = 0, hlPos = 0;
490
491 if (storePos) {
492 // save current src buffer positions
493 llPos = ll.GetBuffPos();
494 hlPos = hl.GetBuffPos();
495 }
496 #endif
497
498 for (UINT32 i=0; i < wquot; i++) {
499 *loRow++ = ll.ReadBuffer();// first access, than increment
500 *loRow++ = hl.ReadBuffer();// first access, than increment
501 }
502 if (wrem) *loRow++ = ll.ReadBuffer();
503
504 #ifdef __PGFROISUPPORT__
505 if (storePos) {
506 // increment src buffer positions
507 ll.IncBuffRow(llPos);
508 hl.IncBuffRow(hlPos);
509 }
510 #endif
511 }
512 }
Friends And Related Function Documentation¶
friend class CSubband [friend]¶
Definition at line 56 of file WaveletTransform.h.
Member Data Documentation¶
int CWaveletTransform::m_nLevels [private]¶
number of LL levels: one more than header.nLevels in PGFimage
Definition at line 141 of file WaveletTransform.h.
CSubband(* CWaveletTransform::m_subband)[NSubbands] [private]¶
quadtree of subbands: LL HL LH HH
Definition at line 142 of file WaveletTransform.h.
Author¶
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| Sat Feb 27 2021 | Version 7.21.2 |