VTK  9.1.0
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"
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{
35public:
37 float f;
38 unsigned int ui;
39 unsigned char ub[4]; // unsigned bytes
40 };
41
42 template <typename T>
43 static inline void EncodeFloatFI(vtkX3DExporterFIByteWriter* writer, T* value, size_t size)
44 {
45 // We want to start at position 3
46 assert(writer->CurrentBytePos == 2);
47
48 // ITU C.19.3.4: If the alternative encoding-algorithm is present,
49 // then the two bits '11' (discriminant) are appended
50 writer->PutBits("11");
51 // ITU 10.8.1: This encoding algorithm has a vocabulary table index of 7,
52 writer->PutBits(7 - 1, 8);
53
54 std::string bytes;
55 char byte[4];
56 for (size_t i = 0; i < size; i++)
57 {
59 v.f = value[i];
60
61 // Avoid -0
62 if (v.ui == 0x80000000)
63 {
64 v.f = 0;
65 }
66
67 byte[0] = v.ub[3];
68 byte[1] = v.ub[2];
69 byte[2] = v.ub[1];
70 byte[3] = v.ub[0];
71
72 bytes.append(byte, 4);
73 }
74 EncodeNonEmptyByteString5(writer, bytes);
75 }
76
77 template <typename T>
78 static inline void EncodeIntegerFI(vtkX3DExporterFIByteWriter* writer, T* value, size_t size)
79 {
80 // We want to start at position 3
81 assert(writer->CurrentBytePos == 2);
82
83 // ITU C.19.3.4: If the alternative encoding-algorithm is present,
84 // then the two bits '11' (discriminant) are appended
85 writer->PutBits("11");
86 // ITU 10.8.1: This encoding algorithm has a vocabulary table index of 4,
87 writer->PutBits(4 - 1, 8);
88 std::string bytes;
89 for (size_t i = 0; i < size; i++)
90 {
91 int v = value[i];
92 int f = ReverseBytes(&v);
93 char* p = reinterpret_cast<char*>(&f);
94 bytes.append(p, 4);
95 }
96 EncodeNonEmptyByteString5(writer, bytes);
97 }
98
99 static inline void EncodeCharacterString3(
100 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(
115 vtkX3DExporterFIByteWriter* writer, const std::string& value)
116 {
117 int length = static_cast<int>(value.length());
118 if (length <= 8)
119 {
120 writer->PutBit(false);
121 writer->PutBits(length - 1, 3);
122 }
123 else if (length <= 264)
124 {
125 writer->PutBits("1000");
126 writer->PutBits(length - 9, 8);
127 }
128 else
129 {
130 writer->PutBits("1100");
131 writer->PutBits(length - 265, 32);
132 }
133 writer->PutBytes(value.c_str(), length);
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(false);
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
205private:
206 static int ReverseBytes(int* x)
207 {
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
217};
218
220{
221
222public:
223 template <typename T>
224 static inline void EncodeIntegerDeltaZ(vtkX3DExporterFIByteWriter* writer, T* value, size_t size,
225 vtkZLibDataCompressor* compressor, bool image = false)
226 {
227 // We want to start at position 3
228 assert(writer->CurrentBytePos == 2);
229
230 // ITU C.19.3.4: If the alternative encoding-algorithm is present,
231 // then the two bits '11' (discriminant) are appended
232 writer->PutBits("11");
233 // ITU 10.8.1: This encoding algorithm has a vocabulary table index of 33
234 writer->PutBits(34 - 1, 8);
235
236 // compute delta
237 char span = 0;
238 size_t i = 0;
239 int f;
240 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)
270 span = 4;
271
272 for (i = 0; i < static_cast<size_t>(span); i++)
273 {
274 int v = 1 + value[i];
275 int* vp = reinterpret_cast<int*>(&v);
276 f = vtkX3DExporterFIWriterHelper::ReverseBytes(vp);
277
278 p = reinterpret_cast<unsigned char*>(&f);
279 deltas.push_back(p[0]);
280 deltas.push_back(p[1]);
281 deltas.push_back(p[2]);
282 deltas.push_back(p[3]);
283 }
284 for (i = span; i < size; i++)
285 {
286 int v = 1 + (value[i] - value[i - span]);
287 f = vtkX3DExporterFIWriterHelper::ReverseBytes(&v);
288
289 p = reinterpret_cast<unsigned char*>(&f);
290 deltas.push_back(p[0]);
291 deltas.push_back(p[1]);
292 deltas.push_back(p[2]);
293 deltas.push_back(p[3]);
294 }
295 }
296
297 size_t bufferSize = deltas.size() + static_cast<unsigned int>(ceil(deltas.size() * 0.001)) + 12;
298 unsigned char* buffer = new unsigned char[bufferSize];
299 size_t newSize = compressor->Compress(&deltas[0], static_cast<unsigned long>(deltas.size()),
300 buffer, static_cast<unsigned long>(bufferSize));
301
302 std::string bytes;
303 int size32 = static_cast<int>(size);
304 int size32_reversed = vtkX3DExporterFIWriterHelper::ReverseBytes(&size32);
305 char* s = reinterpret_cast<char*>(&size32_reversed);
306 bytes.append(s, 4);
307 bytes.append(&span, 1);
308
309 for (i = 0; i < newSize; i++)
310 {
311 unsigned char c = buffer[i];
312 bytes += c;
313 }
314 delete[] buffer;
315
317 if (image)
318 {
319 compressor->SetCompressionLevel(5);
320 }
321 }
322
323 static inline void EncodeQuantizedzlibFloatArray(vtkX3DExporterFIByteWriter* writer,
324 const double* value, size_t size, vtkZLibDataCompressor* compressor)
325 {
326 // We want to start at position 3
327 assert(writer->CurrentBytePos == 2);
328
329 // ITU C.19.3.4: If the alternative encoding-algorithm is present,
330 // then the two bits '11' (discriminant) are appended
331 writer->PutBits("11");
332 // ITU 10.8.1: This encoding algorithm has a vocabulary table index of 33
333 writer->PutBits(34, 8);
334
335 unsigned char* bytes = new unsigned char[size * 4];
336 unsigned char* bytepos = bytes;
337 std::string bytesCompressed;
338 size_t i;
339
340 const double* vd = value;
341 for (i = 0; i < size; i++)
342 {
343 union float_to_unsigned_int_to_bytes {
344 float f;
345 unsigned int ui;
346 unsigned char ub[4]; // unsigned bytes
347 };
348 float_to_unsigned_int_to_bytes v;
349 v.f = (*vd) * 2.0;
350
351 // Avoid -0
352 if (v.ui == 0x80000000)
353 {
354 v.f = 0.0f;
355 }
356 // vtkGenericWarningMacro(<< "value: " << v << " bytes: " << (int)s[0] << " " << (int)s[1] <<
357 // " " << (int)s[2] << " " << (int)s[3]);
358 *bytepos++ = v.ub[3];
359 *bytepos++ = v.ub[2];
360 *bytepos++ = v.ub[1];
361 *bytepos++ = v.ub[0];
362 vd++;
363 }
364
365 // Compress the data
366 size_t bufferSize = (size * 4) + static_cast<size_t>(ceil((size * 4) * 0.001)) + 12;
367 unsigned char* buffer = new unsigned char[bufferSize];
368 size_t newSize = compressor->Compress(
369 bytes, static_cast<unsigned long>(size * 4), buffer, static_cast<unsigned long>(bufferSize));
370
371 char* s;
372 // Put the number of bits for exponent
373 bytesCompressed += static_cast<char>(8);
374 // Put the number of bits for mantissa
375 bytesCompressed += static_cast<char>(23);
376 // Put the length
377 int length = static_cast<int>(size * 4);
378 int length_reversed = vtkX3DExporterFIWriterHelper::ReverseBytes(&length);
379 s = reinterpret_cast<char*>(&length_reversed);
380 bytesCompressed.append(s, 4);
381
382 // Put the number of floats
383 int numFloats = static_cast<int>(size);
384 int numFloats_reversed = vtkX3DExporterFIWriterHelper::ReverseBytes(&numFloats);
385 s = reinterpret_cast<char*>(&numFloats_reversed);
386 bytesCompressed.append(s, 4);
387
388 for (i = 0; i < newSize; i++)
389 {
390 unsigned char c = buffer[i];
391 bytesCompressed += c;
392 }
394 delete[] buffer;
395 delete[] bytes;
396 }
397};
398
399#endif
400// VTK-HeaderTest-Exclude: vtkX3DExporterFIWriterHelper.h
static void EncodeQuantizedzlibFloatArray(vtkX3DExporterFIByteWriter *writer, const double *value, size_t size, vtkZLibDataCompressor *compressor)
static void EncodeIntegerDeltaZ(vtkX3DExporterFIByteWriter *writer, T *value, size_t size, vtkZLibDataCompressor *compressor, bool image=false)
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 EncodeInteger2(vtkX3DExporterFIByteWriter *writer, unsigned int value)
static void EncodeInteger3(vtkX3DExporterFIByteWriter *writer, unsigned int value)
static void EncodeCharacterString3(vtkX3DExporterFIByteWriter *writer, const std::string &value)
static void EncodeLineFeed(vtkX3DExporterFIByteWriter *writer)
static void EncodeIntegerFI(vtkX3DExporterFIByteWriter *writer, T *value, size_t size)
static void EncodeFloatFI(vtkX3DExporterFIByteWriter *writer, T *value, size_t size)
static void EncodeNonEmptyByteString5(vtkX3DExporterFIByteWriter *writer, const std::string &value)
Data compression using zlib.
void SetCompressionLevel(int compressionLevel) override
Get/Set the compression level.