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vtkX3DExporterFIWriterHelper.h
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1 /*=========================================================================
2 
3  Program: Visualization Toolkit
4  Module: vtkX3DExporterFIWriterHelper.h
5 
6  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
7  All rights reserved.
8  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.
9 
10  This software is distributed WITHOUT ANY WARRANTY; without even
11  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
12  PURPOSE. See the above copyright notice for more information.
13 
14 =========================================================================*/
20 #ifndef vtkX3DExporterFIWriterHelper_h
21 #define vtkX3DExporterFIWriterHelper_h
22 
23 //#include "vtkX3DExporterFIByteWriter.h"
24 #include "vtkZLibDataCompressor.h"
25 #include <cassert>
26 
27 #define EXPONENT_MASK_32 0x7f800000
28 #define MANTISSA_MASK_32 0x007fffff
29 
30 #ifndef max
31 #define max(a,b) (((a) > (b)) ? (a) : (b))
32 #endif
34 {
35 public:
37  {
38  float f;
39  unsigned int ui;
40  unsigned char ub[4]; // unsigned bytes
41  };
42 
43  template<typename T>
44  static inline void EncodeFloatFI(vtkX3DExporterFIByteWriter* writer, T* value, size_t size)
45  {
46  // We want to start at position 3
47  assert(writer->CurrentBytePos == 2);
48 
49  // ITU C.19.3.4: If the alternative encoding-algorithm is present,
50  // then the two bits '11' (discriminant) are appended
51  writer->PutBits("11");
52  // ITU 10.8.1: This encoding algorithm has a vocabulary table index of 7,
53  writer->PutBits(7-1, 8);
54 
55  std::string bytes;
56  char byte[4];
57  for (size_t i = 0; i < size; i++)
58  {
60  v.f = value[i];
61 
62  // Avoid -0
63  if (v.ui == 0x80000000)
64  {
65  v.f = 0;
66  }
67 
68  byte[0] = v.ub[3];
69  byte[1] = v.ub[2];
70  byte[2] = v.ub[1];
71  byte[3] = v.ub[0];
72 
73  bytes.append(byte, 4);
74  }
75  EncodeNonEmptyByteString5(writer, bytes);
76  }
77 
78  template<typename T>
79  static inline void EncodeIntegerFI(vtkX3DExporterFIByteWriter* writer, T* value, size_t size)
80  {
81  // We want to start at position 3
82  assert(writer->CurrentBytePos == 2);
83 
84  // ITU C.19.3.4: If the alternative encoding-algorithm is present,
85  // then the two bits '11' (discriminant) are appended
86  writer->PutBits("11");
87  // ITU 10.8.1: This encoding algorithm has a vocabulary table index of 4,
88  writer->PutBits(4-1, 8);
89  std::string bytes;
90  for(size_t i = 0; i < size; i++)
91  {
92  int v = value[i];
93  int f = ReverseBytes(&v);
94  char *p = reinterpret_cast <char*> (&f);
95  bytes.append(p, 4);
96  }
97  EncodeNonEmptyByteString5(writer, bytes);
98  }
99 
100  static inline void EncodeCharacterString3(vtkX3DExporterFIByteWriter* writer, const std::string& value)
101  {
102  // We want to start at position 3
103  assert(writer->CurrentBytePos == 2);
104 
105  // ITU C.19.3.1 If the alternative utf-8 is present, then the two bits '00'
106  // are appended to the bit stream.
107  writer->PutBits("00");
108  // ITU C.19.4: The component bytes is encoded as described in C.23.
109  EncodeNonEmptyByteString5(writer, value);
110  }
111 
112  // ITU C.23: Encoding of the NonEmptyByteString starting
113  // on the fifth bit of an byte
114  static inline void EncodeNonEmptyByteString5(vtkX3DExporterFIByteWriter* writer, const std::string& value)
115  {
116  int length = static_cast<int>(value.length());
117  if (length <= 8)
118  {
119  writer->PutBit(0);
120  writer->PutBits(length - 1, 3);
121  }
122  else if (length <= 264)
123  {
124  writer->PutBits("1000");
125  writer->PutBits(length - 9, 8);
126  }
127  else
128  {
129  writer->PutBits("1100");
130  writer->PutBits(length - 265, 32);
131  }
132  writer->PutBytes(value.c_str(), length);
133  }
134 
135 
136  // ITU C.27: Encoding of integers in the range 1 to 2^20
137  // starting on the third bit of an byte
138  static inline void EncodeInteger3(vtkX3DExporterFIByteWriter* writer, unsigned int value)
139  {
140  // We want to start at position 3
141  assert(writer->CurrentBytePos == 2);
142 
143  if (value <= 32) // ITU C.27.2
144  {
145  writer->PutBit(0);
146  writer->PutBits(value - 1, 5);
147  }
148  else if (value <= 2080) // ITU C.27.3
149  {
150  writer->PutBits("100");
151  writer->PutBits(value - 33, 11);
152  }
153  else if (value < 526368) // ITU C.27.4
154  {
155  writer->PutBits("101");
156  writer->PutBits(value - 2081, 19);
157  }
158  else // ITU C.27.5
159  {
160  writer->PutBits("1100000000");
161  writer->PutBits(value - 526369, 20);
162  }
163  }
164 
165  // ITU C.25: Encoding of integers in the range 1 to 2^20
166  // starting on the second bit of an byte
167  static inline void EncodeInteger2(vtkX3DExporterFIByteWriter* writer, unsigned int value)
168  {
169  // We want to start at position 2
170  assert(writer->CurrentBytePos == 1);
171 
172  if (value <= 64) // ITU C.25.2
173  {
174  writer->PutBits("0");
175  writer->PutBits(value - 1, 6);
176  }
177  else if (value <= 8256) // ITU C.25.3
178  {
179  writer->PutBits("10");
180  writer->PutBits(value - 65, 13);
181  }
182  else // ITU C.25.4
183  {
184  writer->PutBits("110");
185  writer->PutBits(value - 8257, 20);
186  }
187  }
188 
189  static inline void EncodeLineFeed(vtkX3DExporterFIByteWriter* writer)
190  {
191  static bool firstTime = true;
192  writer->FillByte();
193  if (firstTime)
194  {
195  writer->PutBits("1001000000001010");
196  firstTime = false;
197  }
198  else
199  {
200  //cout << "Encode NOT the first time" << endl;
201  writer->PutBits("10100000");
202  }
203  }
204 
205 private:
206 
207  static int ReverseBytes(int* x) {
208  /* break x apart, then put it back together backwards */
209  int part1 = (*x) & 0xFF;
210  int part2 = ((*x) >> 8) & 0xFF;
211  int part3 = ((*x) >> 16) & 0xFF;
212  int part4 = ((*x) >> 24) & 0xFF;
213  return (part1 << 24) | ( part2 << 16) | (part3 << 8) | part4;
214  }
215 
216 
217  friend class X3DEncoderFunctions;
218 };
219 
221 
222 
223 
224 public:
225  template<typename T>
226  static inline void EncodeIntegerDeltaZ(vtkX3DExporterFIByteWriter* writer, T* value, size_t size, vtkZLibDataCompressor* compressor, bool image = false)
227  {
228  // We want to start at position 3
229  assert(writer->CurrentBytePos == 2);
230 
231  // ITU C.19.3.4: If the alternative encoding-algorithm is present,
232  // then the two bits '11' (discriminant) are appended
233  writer->PutBits("11");
234  // ITU 10.8.1: This encoding algorithm has a vocabulary table index of 33
235  writer->PutBits(34-1, 8);
236 
237  // compute delta
238  char span = 0;
239  size_t i = 0;
240  int f; unsigned char *p;
241  std::vector<unsigned char> deltas;
242 
243  if (image)
244  {
245  span = 0;
246  for(i = 0; i < size; i++)
247  {
248  int v = 1 + (value[i]);
249  int *vp = reinterpret_cast<int*>(&v);
250  f = vtkX3DExporterFIWriterHelper::ReverseBytes(vp);
251  p = reinterpret_cast <unsigned char*> (&f);
252  deltas.push_back(p[0]);
253  deltas.push_back(p[1]);
254  deltas.push_back(p[2]);
255  deltas.push_back(p[3]);
256  }
257  compressor->SetCompressionLevel(9);
258  }
259  else
260  {
261  for (i = 0; i < 20; i++)
262  {
263  if (value[i] == -1)
264  {
265  span = static_cast<char>(i) + 1;
266  break;
267  }
268  }
269  if (!span) span = 4;
270 
271  for(i = 0; i < static_cast<size_t>(span); i++)
272  {
273  int v = 1 + value[i];
274  int *vp = reinterpret_cast<int*>(&v);
275  f = vtkX3DExporterFIWriterHelper::ReverseBytes(vp);
276 
277  p = reinterpret_cast <unsigned char*> (&f);
278  deltas.push_back(p[0]);
279  deltas.push_back(p[1]);
280  deltas.push_back(p[2]);
281  deltas.push_back(p[3]);
282  }
283  for(i = span; i < size; i++)
284  {
285  int v = 1 + (value[i] - value[i-span]);
286  f = vtkX3DExporterFIWriterHelper::ReverseBytes(&v);
287 
288  p = reinterpret_cast <unsigned char*> (&f);
289  deltas.push_back(p[0]);
290  deltas.push_back(p[1]);
291  deltas.push_back(p[2]);
292  deltas.push_back(p[3]);
293  }
294  }
295 
296  size_t bufferSize = deltas.size() + static_cast<unsigned int>(ceil(deltas.size()*0.001)) + 12;
297  unsigned char* buffer = new unsigned char[bufferSize];
298  size_t newSize = compressor->Compress(&deltas[0],static_cast<unsigned long>(deltas.size()), buffer, static_cast<unsigned long>(bufferSize));
299 
300  std::string bytes;
301  int size32 = static_cast<int>(size);
302  int size32_reversed = vtkX3DExporterFIWriterHelper::ReverseBytes(&size32);
303  char *s = reinterpret_cast <char*> (&size32_reversed);
304  bytes.append(s, 4);
305  bytes.append(&span, 1);
306 
307  for (i = 0; i < newSize; i++)
308  {
309  unsigned char c = buffer[i];
310  bytes += c;
311  }
312  delete [] buffer;
313 
315  if (image)
316  {
317  compressor->SetCompressionLevel(5);
318  }
319  }
320 
321  static inline void EncodeQuantizedzlibFloatArray(vtkX3DExporterFIByteWriter* writer, const double* value, size_t size, vtkZLibDataCompressor* compressor)
322  {
323  // We want to start at position 3
324  assert(writer->CurrentBytePos == 2);
325 
326  // ITU C.19.3.4: If the alternative encoding-algorithm is present,
327  // then the two bits '11' (discriminant) are appended
328  writer->PutBits("11");
329  // ITU 10.8.1: This encoding algorithm has a vocabulary table index of 33
330  writer->PutBits(34, 8);
331 
332  unsigned char* bytes = new unsigned char[size*4];
333  unsigned char* bytepos = bytes;
334  std::string bytesCompressed;
335  size_t i;
336 
337  const double* vd = value;
338  for (i = 0; i < size; i++)
339  {
340  union float_to_unsigned_int_to_bytes
341  {
342  float f;
343  unsigned int ui;
344  unsigned char ub[4]; // unsigned bytes
345  };
346  float_to_unsigned_int_to_bytes v;
347  v.f = (*vd) * 2.0;
348 
349  // Avoid -0
350  if (v.ui == 0x80000000)
351  {
352  v.f = 0.0f;
353  }
354  //vtkGenericWarningMacro(<< "value: " << v << " bytes: " << (int)s[0] << " " << (int)s[1] << " " << (int)s[2] << " " << (int)s[3]);
355  *bytepos++ = v.ub[3];
356  *bytepos++ = v.ub[2];
357  *bytepos++ = v.ub[1];
358  *bytepos++ = v.ub[0];
359  vd++;
360  }
361 
362 
363  // Compress the data
364  size_t bufferSize = (size * 4) + static_cast<size_t>(ceil((size * 4)*0.001)) + 12;
365  unsigned char* buffer = new unsigned char[bufferSize];
366  size_t newSize = compressor->Compress(bytes,
367  static_cast<unsigned long>(size * 4), buffer,
368  static_cast<unsigned long>(bufferSize));
369 
370  char *s;
371  // Put the number of bits for exponent
372  bytesCompressed += static_cast<char>(8);
373  // Put the number of bits for mantissa
374  bytesCompressed += static_cast<char>(23);
375  // Put the length
376  int length = static_cast<int>(size*4);
377  int length_reversed = vtkX3DExporterFIWriterHelper::ReverseBytes(&length);
378  s = reinterpret_cast <char*> (&length_reversed);
379  bytesCompressed.append(s, 4);
380 
381  // Put the number of floats
382  int numFloats = static_cast<int>(size);
383  int numFloats_reversed = vtkX3DExporterFIWriterHelper::ReverseBytes(&numFloats);;
384  s = reinterpret_cast <char*> (&numFloats_reversed);
385  bytesCompressed.append(s, 4);
386 
387  for (i = 0; i < newSize; i++)
388  {
389  unsigned char c = buffer[i];
390  bytesCompressed += c;
391  }
393  delete [] buffer;
394  delete [] bytes;
395  }
396 
397 };
398 
399 #endif
400 // VTK-HeaderTest-Exclude: vtkX3DExporterFIWriterHelper.h
static void EncodeNonEmptyByteString5(vtkX3DExporterFIByteWriter *writer, const std::string &value)
static void EncodeIntegerDeltaZ(vtkX3DExporterFIByteWriter *writer, T *value, size_t size, vtkZLibDataCompressor *compressor, bool image=false)
static void EncodeCharacterString3(vtkX3DExporterFIByteWriter *writer, const std::string &value)
virtual void SetCompressionLevel(int)
Get/Set the compression level.
static void EncodeInteger2(vtkX3DExporterFIByteWriter *writer, unsigned int value)
Data compression using zlib.
size_t Compress(unsigned char const *uncompressedData, size_t uncompressedSize, unsigned char *compressedData, size_t compressionSpace)
Compress the given input data buffer into the given output buffer.
static void EncodeInteger3(vtkX3DExporterFIByteWriter *writer, unsigned int value)
static void EncodeFloatFI(vtkX3DExporterFIByteWriter *writer, T *value, size_t size)
static void EncodeQuantizedzlibFloatArray(vtkX3DExporterFIByteWriter *writer, const double *value, size_t size, vtkZLibDataCompressor *compressor)
static void EncodeIntegerFI(vtkX3DExporterFIByteWriter *writer, T *value, size_t size)
static void EncodeLineFeed(vtkX3DExporterFIByteWriter *writer)