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ocssw V2022
common.cpp
Go to the documentation of this file.
1 #include <algorithm>
2 #include <iterator>
3 
4 #include "common.h"
5 
6 using namespace std;
7 
8 #define BAGGBASE 2863311530
9 #define RAGGBASE 2774100650
10 
11 // Modification history:
12 // Programmer Organization Date Ver Description of change
13 // ---------- ------------ ---- --- ---------------------
14 // Joel Gales FutureTech 08/02/19 0.10 Original development
15 // Liang Hong SAIC 04/14/22 0.20 l1agen_oci v1.03.00
16 // Liang Hong SAIC 04/24/22 0.21 l1agen_oci v1.03.02
17 // Liang Hong SAIC 05/05/22 0.30 l1agen_oci v1.04.00
18 // Liang Hong SAIC 11/18/22 0.40 l1agen_oci v1.06.00
19 // Jakob Lindo SSAI 03/16/24 0.50 Added aggregation indication
20 
21 int get_band_dims(uint8_t *apacket, uint16_t &ncp, uint16_t &nbb, uint16_t &nrb, uint16_t &nsp, uint16_t &ndc,
22  uint16_t &nds, uint16_t *btaps, uint16_t *rtaps, itab *itable) {
23  // Extract spatial aggregation table and compute numbers of pixels
24  short ioff = 36;
25  short nagg[4] = {1, 2, 4, 8};
26  ncp = 0;
27  nsp = 0;
28  ndc = 0;
29  nds = 0;
30 
31  for (size_t i = 0; i < 10; i++) {
32  itable[i].dtype = apacket[ioff + 3] % 16;
33  itable[i].iagg = apacket[ioff + 2] % 4;
34  if (itable[i].dtype == 5)
35  itable[i].iagg = 0;
36  itable[i].lines = apacket[ioff] * 256 + apacket[ioff + 1];
37  ioff += 4;
38 
39  if (itable[i].dtype > 0 && itable[i].dtype <= 14 &&
40  itable[i].dtype != 10) { // Changed dtype<=12 to 14, LH, 3/30/2022
41  if (itable[i].dtype == 2) {
42  ndc += itable[i].lines / nagg[itable[i].iagg];
43  nds += itable[i].lines / 8;
44  } // else { Changed to include dark pixels, Liang Hong, 5/12/2020
45  ncp += itable[i].lines / nagg[itable[i].iagg];
46  nsp += itable[i].lines / 8;
47  // }
48  }
49  }
50 
51  // to ensure that the science and dark count arrays will be created with at least one pixel
52  if (ncp == 0) {
53  ncp = 1;
54  nsp = 1;
55  }
56 
57  if (ndc == 0) {
58  ndc = 1;
59  nds = 1;
60  }
61 
62  ioff += 4;
63 
64  // Extract spectral aggregation and compute numbers of bands
65  // Tap enable flags
66  short btap = apacket[ioff + 2] * 256 + apacket[ioff + 3];
67  short rtap = apacket[ioff] * 256 + apacket[ioff + 1];
68 
69  // Tap aggregation factors
70  uint32_t bagg;
71  uint32_t ragg;
72  memcpy(&bagg, &apacket[ioff + 8], sizeof(uint32_t));
73  memcpy(&ragg, &apacket[ioff + 4], sizeof(uint32_t));
74  bagg = SWAP_4(bagg);
75  ragg = SWAP_4(ragg);
76 
77  if (itable[1].dtype == 1 && (bagg != BAGGBASE || ragg != RAGGBASE))
78  itable[1].dtype = 13;
79 
80  // Compute number of bands for enabled taps
81  // Bands are in reverse spectral order
82  nbb = 0;
83  nrb = 0;
84  uint16_t ken = 1;
85  uint32_t kag = 3;
86  uint32_t lag = 1;
87 
88  // for (size_t i=0; i<16; i++) {
89  for (int i = 15; i >= 0; i--) {
90  btaps[i] = (btap & ken) / ken;
91  if (btaps[i])
92  nbb += 32 / nagg[(bagg & kag) / lag];
93  rtaps[i] = (rtap & ken) / ken;
94  if (rtaps[i])
95  nrb += 32 / nagg[(ragg & kag) / lag];
96  ken *= 2;
97  kag *= 4;
98  lag *= 4;
99  }
100 
101  return 0;
102 }
103 
104 int get_anc_packet_time(uint8_t *apacket, int32_t &iyear, int32_t &iday, double &stime) {
105  // Unpack and convert the CCSDS segmented time code
106  // from the OCI ancillary packet
107 
108  // Get day count since Jan. 1, 1958 (Julian day 2436205)
109  // sec58 = seconds since 0 UT Jan. 1, 1958
110  short int toff = 28;
111  uint32_t sec58;
112  memcpy(&sec58, &apacket[toff], sizeof(uint32_t));
113  sec58 = SWAP_4(sec58);
114 
115  double dbl58 = (double)sec58;
116  int leap = leapseconds_since_1993(dbl58) + 27;
117  sec58 -= leap;
118 
119  // Convert to year and day
120  iday = sec58 / 86400;
121  int32_t jd = iday + 2436205; // Jan. 1, 1958 is Julian day 2436205
122  jdate(jd, &iyear, &iday);
123 
124  // Get microseconds
125  uint32_t usec;
126  memcpy(&usec, &apacket[toff + 4], sizeof(uint32_t));
127  usec = SWAP_4(usec);
128  usec = usec / 4096; // 20 MSBs used, last 12 are spares
129 
130  uint32_t isec = sec58 % 86400;
131  stime = isec + ((double)usec) * 1e-6;
132 
133  return 0;
134 }
135 
136 int read_oci_scan_packets(L0Stream *tfileStream, uint8_t *apacket, uint8_t (*pbuffer)[PKTSIZE],
137  uint32_t &npkts, int32_t &spnum, int32_t &ancind, vector<int32_t> &tlmind,
138  uint8_t &seqerr, int32_t &endfile, bool isSPW) {
139  // int pos = tfileStream->tellg();
140  if (endfile)
141  return 0; // LH, 4/24/2022, v1.03.02
142 
143  uint32_t apidmin = 636; // ver
144  uint32_t apidmax = 745; // ver 1.00.00, LH, 1/7/2022
145  uint32_t ui32;
146  uint32_t len;
147  uint32_t maxpkts = 30000; // ver 0.20, LH, 4/14/2022
148 
149  // Ancillary packet APID
150  static uint32_t apida = 636;
151 
152  // APIDs with time fields and spin numbers
153  static uint32_t apidt[8] = {
154  711, 712, 713, 715,
155  716, 717, 721, 723}; // telemetry APIDs with time fields and spin numbers, ver 0.30, LH, 5/5/2022
156 
157  // APIDs with spin numbers but no time fields
158  static uint32_t apidn[2] = {700, 720};
159 
160  // Get OCI spin number from first packet of next scan
161  uint32_t apid = (apacket[0] % 8) * 256 + apacket[1];
162 
163  npkts = 0;
164  tlmind.clear();
165  ancind = -1;
166  // int spne = 0;
167 
168  if (apid == apida) {
169  // Ancillary packet
170  memcpy(&ui32, &apacket[24], 4);
171  spnum = SWAP_4(ui32);
172  } else if (apid == apidn[0] || apid == apidn[1]) {
173  // Science Packet without time field, ignore SWIR packets for now
174  memcpy(&ui32, &apacket[6], 4);
175  spnum = SWAP_4(ui32);
176  // } else if (apid == apidt[0] || apid == apidt[1] || apid == apidt[2] ||apid == apidt[3]) {
177  } else if (std::find(std::begin(apidt), std::end(apidt), apid) != std::end(apidt)) {
178  // Packet with time field
179  memcpy(&ui32, &apacket[12], 4);
180  spnum = SWAP_4(ui32);
181  }
182 
183  // uint32_t spn = spnum;
184  // uint32_t spnt = spnum;
185  int32_t spn = spnum;
186  int32_t spnt = spnum;
187  uint8_t *packet = apacket;
188 
189  len = apacket[4] * 256 + apacket[5] + 7;
190 
191  int prev_pseq = 0;
192  seqerr = 0;
193 
194  // Read all of the packets with this spin number
195  // and store in the packet buffer
196  while (spn <= spnum && spnt <= (spnum + 1) && (npkts < maxpkts)) {
197  // Check for packet out of order
198  // Load packet into buffer
199  memcpy(&pbuffer[npkts][0], packet, len);
200  apid = (packet[0] % 8) * 256 + packet[1];
201 
202  // Check science packet sequence numbers, LH 11/20/2020
203  if (apid == apidn[0]) {
204  int pseq = (pbuffer[npkts][2] % 64) * 256 + pbuffer[npkts][3];
205  if ((prev_pseq > 0) && ((pseq - prev_pseq) != 1 && (pseq - prev_pseq) != -16383)) {
206  // cout<<"npkts="<<npkts<<"pseq,pseq-prev_pseq="<<pseq<<","<<pseq-prev_pseq<<endl;
207  seqerr = 1;
208  }
209  prev_pseq = pseq;
210  }
211 
212  if (apid == apida)
213  ancind = npkts;
214  // if (pos >= 527223898) {
215  // pos = tfileStream->tellg();
216  // cout << pos << " " << apid << " " << apida << " " << ancind
217  // << spnum << " " << spn << " " << spnt << endl;
218  //}
219 
220  if (apid >= apidmin & apid <= apidmax && apid != apidn[0] && apid != apidn[1]) {
221  tlmind.push_back(npkts);
222  }
223  npkts++;
224  if (npkts == maxpkts) {
225  cout << "Maximum number of packets: " << maxpkts << " exceeded." << endl;
226  // exit (1); // Liang Hong, 08/19/2020
227  }
228  // cout << apid << " " << npkts << endl;
229 
230  // Read next packet
231  read_packet(tfileStream, NULL, len, apid, endfile, isSPW);
232  if (endfile)
233  return 0;
234 
235  if (len > PKTSIZE) {
236  cout << "Packet size > " << PKTSIZE << " (" << len << ")" << endl;
237  uint8_t *dummy_buf = new uint8_t[len];
238  read_packet(tfileStream, dummy_buf, len, apid, endfile, isSPW);
239  delete[] dummy_buf;
240  // exit(1);
241  } else {
242  read_packet(tfileStream, packet, len, apid, endfile, isSPW);
243  apid = (packet[0] % 8) * 256 + packet[1];
244  }
245 
246  while (apid < apidmin || apid > apidmax) {
247  read_packet(tfileStream, NULL, len, apid, endfile, isSPW);
248  if (endfile)
249  return 0;
250 
251  if (len > PKTSIZE) {
252  cout << "Packet size > " << PKTSIZE << " (" << len << ")" << endl;
253  uint8_t *dummy_buf = new uint8_t[len];
254  read_packet(tfileStream, dummy_buf, len, apid, endfile, isSPW);
255  delete[] dummy_buf;
256  // exit(1);
257  } else {
258  read_packet(tfileStream, packet, len, apid, endfile, isSPW);
259  apid = (packet[0] % 8) * 256 + packet[1];
260  }
261  }
262 
263  // Get spin number
264  if (apid == apida) {
265  memcpy(&ui32, &packet[24], 4);
266  spn = SWAP_4(ui32);
267  } else if (apid == apidn[0] || apid == apidn[1]) { // ver 1.00.01
268  memcpy(&ui32, &packet[6], 4);
269  spn = SWAP_4(ui32);
270  // } else if (apid == apidt[0] || apid == apidt[1] || apid == apidt[2] || apid == apidt[3]) {
271  } else if (std::find(std::begin(apidt), std::end(apidt), apid) != std::end(apidt)) {
272  memcpy(&ui32, &packet[12], 4);
273  spnt = SWAP_4(ui32);
274  } // if (apid == apidn[0] || apid == apidn[1]) {
275 
276  } // while (spn <= spnum && spnt <= spnum)
277 
278  // Report spin out of order
279  // if (spn < spnum)
280  // cout << "Next packet spin number: " << spn
281  // << " out of order for spin: " << spnum << endl;
282  // cout << "npkts: " << npkts << endl;
283 
284  return 0;
285 }
286 
287 int anc_compare(uint8_t *apacket0, uint8_t *apacket) {
288  int anc_compare = 1;
289 
290  double stime;
291  int32_t iyear, iday;
292  uint32_t ui32;
293 
294  if (apacket[15] > 0)
295  return anc_compare; // ancillary packet without valid mode table, v0.20
296 
297  // Compare spatial data collection fields
298  int ioff = 36;
299  size_t ilen = 40;
300 
301  uint16_t aggi = 0;
302  for (size_t i = 0; i < ilen; i++)
303  if (apacket[ioff + i] != apacket0[ioff + i])
304  aggi++;
305 
306  if (aggi > 0) {
307  get_anc_packet_time(apacket, iyear, iday, stime);
308  memcpy(&ui32, &apacket[24], 4);
309  int32_t spn = SWAP_4(ui32);
310  uint16_t ih = (uint16_t)floor(stime / 3600);
311  uint16_t mn = (uint16_t)floor((stime - ih * 3600) / 60);
312  uint16_t sec = (uint16_t)floor(stime - ih * 3600 - mn * 60);
313  cout << "Spatial table change at: spin=" << spn << ", " << ih << ":" << mn << ":" << sec << endl;
314  anc_compare = 0;
315  }
316 
317  // Compare spectral data collection fields
318  // int joff = 76;
319  // size_t jlen = 16;
320  int joff = 80;
321  size_t jlen = 12;
322 
323  uint16_t aggj = 0;
324  for (size_t i = 0; i < jlen; i++)
325  if (apacket[joff + i] != apacket0[joff + i])
326  aggj++;
327 
328  if (aggj > 0) {
329  get_anc_packet_time(apacket, iyear, iday, stime);
330  memcpy(&ui32, &apacket[24], 4);
331  int32_t spn = SWAP_4(ui32);
332  uint16_t ih = (uint16_t)floor(stime / 3600);
333  uint16_t mn = (uint16_t)floor((stime - ih * 3600) / 60);
334  uint16_t sec = (uint16_t)floor(stime - ih * 3600 - mn * 60);
335  cout << "Spectral table change at: spin=" << spn << ", " << ih << ":" << mn << ":" << sec << endl;
336  anc_compare = 0;
337  }
338 
339  return anc_compare;
340 }
341 
342 int read_packet(L0Stream *tfileStream, uint8_t *packet, uint32_t &len, uint32_t &apid, int32_t &endfile,
343  bool isSPW) {
344  if (tfileStream->eof()) {
345  endfile = 1;
346  len = 0;
347  cout << "End of packet file" << endl;
348  return 0;
349  }
350 
351  // Read spacewire header if needed
352  if (isSPW) {
353  uint8_t spwhead[2];
354  tfileStream->read((char *)&spwhead, 2);
355  }
356 
357  // Read packet header
358  uint8_t phead[6];
359  if (packet == NULL) {
360  tfileStream->read((char *)&phead, 6);
361 
362  // Get length of packet body and APID
363  len = phead[4] * 256 + phead[5] + 1 + 6;
364  apid = (phead[0] % 8) * 256 + phead[1];
365 
366  if (tfileStream->tellg() == -1)
367  endfile = 1;
368  tfileStream->seekg(-6, ios_base::cur);
369  if (isSPW)
370  tfileStream->seekg(-2, ios_base::cur);
371  return 0;
372  }
373  tfileStream->read((char *)packet, len);
374  // cout << tfileStream->tellg() << endl;
375 
376  return 0;
377 }
378 
379 int get_swir_mode(uint8_t (*pbuffer)[PKTSIZE], uint32_t npkts, uint16_t &smode) {
380  // Look for a SWIR band packet
381 
382  // smode = 0;
383  for (size_t ipkt = 0; ipkt < npkts; ipkt++) {
384  uint32_t apid = (pbuffer[ipkt][0] % 8) * 256 + pbuffer[ipkt][1];
385  // if (npkts == 5) cout << "apid: " << apid << endl;
386  if (apid == 720) {
387  // Get mode from packet
388  uint8_t smeta = pbuffer[ipkt][12];
389  smode = (smeta % 64) / 16;
390  return 0;
391  }
392  }
393 
394  return 0;
395  // cout << "SWIR mode not found" << endl;
396  // exit(1);
397 }
L0Stream::tellg
int tellg()
Obtain the position of the read/write head from the beginning of the current filestream.
Definition: l0stream.cpp:146
get_swir_mode
int get_swir_mode(uint8_t(*pbuffer)[PKTSIZE], uint32_t npkts, uint16_t &smode)
Definition: common.cpp:379
itab::lines
short lines
Definition: common.h:13
read_packet
int read_packet(L0Stream *tfileStream, uint8_t *packet, uint32_t &len, uint32_t &apid, int32_t &endfile, bool isSPW)
Definition: common.cpp:342
NULL
#define NULL
Definition: decode_rs.h:63
itab::dtype
short dtype
Definition: common.h:11
L0Stream::seekg
void seekg(std::streamoff num, std::ios_base::seekdir dir)
Move the read/write head a number of bytes in a particular direction, switching streams as necessary.
Definition: l0stream.cpp:115
SWAP_4
#define SWAP_4(x)
Definition: common.h:18
L0Stream
A class to simulate a single stream object over multiple OCI L0 files.
Definition: l0stream.hpp:16
jdate
int jdate(int32_t julian, int32_t *year, int32_t *doy)
Takes in a julian day and mutates year and doy to contain the gregorian year and day of that gregoria...
Definition: jdate.c:13
common.h
leapseconds_since_1993
int leapseconds_since_1993(double tai93time)
Definition: leapsecond.c:58
L0Stream::read
void read(char *buffer, size_t num)
Read from the current stream, switching streams as necessary.
Definition: l0stream.cpp:83
get_anc_packet_time
int get_anc_packet_time(uint8_t *apacket, int32_t &iyear, int32_t &iday, double &stime)
Definition: common.cpp:104
BAGGBASE
#define BAGGBASE
Definition: common.cpp:8
jd
Definition: jd.py:1
generalauxtype::double
integer, parameter double
Definition: GeneralAuxType.f90:27
ih
int32_t ih
Definition: atrem_corl1.h:161
anc_compare
int anc_compare(uint8_t *apacket0, uint8_t *apacket)
Definition: common.cpp:287
ioff
int32 ioff
Definition: get_dem_height.c:17
dtype
dtype
Definition: DDataset.hpp:31
itab
Definition: common.h:10
L0Stream::eof
bool eof()
Indicate if fstream::eof is true.
Definition: l0stream.cpp:139
RAGGBASE
#define RAGGBASE
Definition: common.cpp:9
itab::iagg
short iagg
Definition: common.h:12
leap
logical function leap(YEAR)
Definition: leap.f:10
check_products.end
end
Definition: check_products.py:189
read_oci_scan_packets
int read_oci_scan_packets(L0Stream *tfileStream, uint8_t *apacket, uint8_t(*pbuffer)[PKTSIZE], uint32_t &npkts, int32_t &spnum, int32_t &ancind, vector< int32_t > &tlmind, uint8_t &seqerr, int32_t &endfile, bool isSPW)
Definition: common.cpp:136
i
int i
Definition: decode_rs.h:71
PKTSIZE
#define PKTSIZE
Definition: common.h:8
get_band_dims
int get_band_dims(uint8_t *apacket, uint16_t &ncp, uint16_t &nbb, uint16_t &nrb, uint16_t &nsp, uint16_t &ndc, uint16_t &nds, uint16_t *btaps, uint16_t *rtaps, itab *itable)
Definition: common.cpp:21


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