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blx.c
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/* libblx - Magellan BLX topo reader/writer library
*
* Copyright (c) 2008, Henrik Johansson <[email protected]>
* Copyright (c) 2008-2009, Even Rouault <even dot rouault at spatialys.com>
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following
* conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
#include "blx.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "cpl_port.h"
/* Constants */
#define MAXLEVELS 5
#define MAXCOMPONENTS 4
static const int table1[] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3,
3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4,
4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5,
5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7,
7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 9, 10, 10, 10,
10, 11, 11, 11, 11, 12, 12, 12, 12, 13, 13, 13, 13, 14, 14,
15, 15, 16, 16, 17, 17, 18, 18, 19, 19, 20, 21, 22, 23, 24,
25, 26, 27, 28, 29, 30, 31, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255};
/* { byte, n of bits when compressed, bit pattern << (13-n of bits) } */
static const int table2[][3] = {
{0, 2, 0}, {255, 3, 2048}, {1, 3, 3072}, {2, 4, 4096},
{3, 4, 4608}, {254, 5, 5120}, {4, 5, 5376}, {5, 5, 5632},
{253, 6, 5888}, {6, 6, 6016}, {252, 6, 6144}, {7, 6, 6272},
{251, 6, 6400}, {8, 6, 6528}, {9, 7, 6656}, {250, 7, 6720},
{10, 7, 6784}, {249, 7, 6848}, {11, 7, 6912}, {248, 7, 6976},
{12, 8, 7040}, {247, 8, 7072}, {16, 8, 7104}, {246, 8, 7136},
{13, 8, 7168}, {245, 8, 7200}, {14, 8, 7232}, {244, 8, 7264},
{15, 8, 7296}, {243, 8, 7328}, {242, 8, 7360}, {241, 8, 7392},
{17, 9, 7424}, {18, 9, 7440}, {240, 9, 7456}, {239, 9, 7472},
{19, 9, 7488}, {238, 9, 7504}, {20, 9, 7520}, {237, 9, 7536},
{21, 9, 7552}, {236, 9, 7568}, {22, 9, 7584}, {235, 9, 7600},
{234, 9, 7616}, {23, 9, 7632}, {233, 9, 7648}, {24, 10, 7664},
{232, 10, 7672}, {231, 10, 7680}, {25, 10, 7688}, {230, 10, 7696},
{229, 10, 7704}, {26, 10, 7712}, {228, 10, 7720}, {27, 10, 7728},
{227, 10, 7736}, {225, 10, 7744}, {226, 10, 7752}, {28, 10, 7760},
{29, 10, 7768}, {224, 10, 7776}, {30, 10, 7784}, {31, 10, 7792},
{223, 10, 7800}, {32, 10, 7808}, {222, 10, 7816}, {33, 10, 7824},
{221, 11, 7832}, {220, 11, 7836}, {34, 11, 7840}, {219, 11, 7844},
{35, 11, 7848}, {218, 11, 7852}, {256, 11, 7856}, {36, 11, 7860},
{217, 11, 7864}, {216, 11, 7868}, {37, 11, 7872}, {215, 11, 7876},
{38, 11, 7880}, {214, 11, 7884}, {193, 11, 7888}, {213, 11, 7892},
{39, 11, 7896}, {128, 11, 7900}, {212, 11, 7904}, {40, 11, 7908},
{194, 11, 7912}, {211, 11, 7916}, {210, 11, 7920}, {41, 11, 7924},
{209, 11, 7928}, {208, 11, 7932}, {42, 11, 7936}, {207, 11, 7940},
{43, 11, 7944}, {195, 11, 7948}, {206, 11, 7952}, {205, 11, 7956},
{204, 11, 7960}, {44, 11, 7964}, {203, 11, 7968}, {192, 11, 7972},
{196, 11, 7976}, {45, 11, 7980}, {201, 11, 7984}, {200, 11, 7988},
{197, 11, 7992}, {202, 11, 7996}, {127, 11, 8000}, {199, 11, 8004},
{198, 11, 8008}, {46, 12, 8012}, {47, 12, 8014}, {48, 12, 8016},
{49, 12, 8018}, {50, 12, 8020}, {51, 12, 8022}, {191, 12, 8024},
{52, 12, 8026}, {183, 12, 8028}, {53, 12, 8030}, {54, 12, 8032},
{55, 12, 8034}, {190, 12, 8036}, {56, 12, 8038}, {57, 12, 8040},
{189, 12, 8042}, {58, 12, 8044}, {176, 12, 8046}, {59, 12, 8048},
{126, 12, 8050}, {60, 12, 8052}, {188, 12, 8054}, {61, 12, 8056},
{63, 12, 8058}, {62, 12, 8060}, {64, 12, 8062}, {129, 12, 8064},
{187, 12, 8066}, {186, 12, 8068}, {65, 12, 8070}, {66, 12, 8072},
{185, 12, 8074}, {184, 12, 8076}, {68, 12, 8078}, {174, 12, 8080},
{67, 12, 8082}, {182, 13, 8084}, {69, 13, 8085}, {180, 13, 8086},
{181, 13, 8087}, {71, 13, 8088}, {70, 13, 8089}, {179, 13, 8090},
{125, 13, 8091}, {72, 13, 8092}, {130, 13, 8093}, {178, 13, 8094},
{177, 13, 8095}, {73, 13, 8096}, {74, 13, 8097}, {124, 13, 8098},
{76, 13, 8099}, {175, 13, 8100}, {75, 13, 8101}, {131, 13, 8102},
{132, 13, 8103}, {79, 13, 8104}, {77, 13, 8105}, {123, 13, 8106},
{80, 13, 8107}, {172, 13, 8108}, {171, 13, 8109}, {78, 13, 8110},
{173, 13, 8111}, {81, 13, 8112}, {169, 13, 8113}, {122, 13, 8114},
{82, 13, 8115}, {133, 13, 8116}, {168, 13, 8117}, {84, 13, 8118},
{164, 13, 8119}, {167, 13, 8120}, {85, 13, 8121}, {170, 13, 8122},
{166, 13, 8123}, {165, 13, 8124}, {121, 13, 8125}, {160, 13, 8126},
{134, 13, 8127}, {136, 13, 8128}, {161, 13, 8129}, {120, 13, 8130},
{88, 13, 8131}, {83, 13, 8132}, {119, 13, 8133}, {163, 13, 8134},
{162, 13, 8135}, {159, 13, 8136}, {91, 13, 8137}, {135, 13, 8138},
{90, 13, 8139}, {86, 13, 8140}, {137, 13, 8141}, {87, 13, 8142},
{89, 13, 8143}, {158, 13, 8144}, {152, 13, 8145}, {138, 13, 8146},
{139, 13, 8147}, {116, 13, 8148}, {140, 13, 8149}, {92, 13, 8150},
{96, 13, 8151}, {157, 13, 8152}, {153, 13, 8153}, {97, 13, 8154},
{94, 13, 8155}, {93, 13, 8156}, {117, 13, 8157}, {156, 13, 8158},
{155, 13, 8159}, {95, 13, 8160}, {118, 13, 8161}, {143, 13, 8162},
{151, 13, 8163}, {142, 13, 8164}, {104, 13, 8165}, {100, 13, 8166},
{148, 13, 8167}, {144, 13, 8168}, {154, 13, 8169}, {115, 13, 8170},
{113, 13, 8171}, {98, 13, 8172}, {146, 13, 8173}, {112, 13, 8174},
{145, 13, 8175}, {149, 13, 8176}, {141, 13, 8177}, {150, 13, 8178},
{103, 13, 8179}, {147, 13, 8180}, {99, 13, 8181}, {108, 13, 8182},
{101, 13, 8183}, {114, 13, 8184}, {105, 13, 8185}, {102, 13, 8186},
{107, 13, 8187}, {109, 13, 8188}, {110, 13, 8189}, {111, 13, 8190},
{106, 13, 8191}, {0, 0, 8192}};
static const int table3[] = {0x20, 0x2f, 0x44, 0x71, 0x95, 0x101};
STATIC int compress_chunk(unsigned char *inbuf, int inlen,
unsigned char *outbuf, int outbuflen)
{
int next, m = 0, j, outlen = 0;
unsigned reg = 0;
next = *inbuf++;
inlen--;
while (next >= 0)
{
/* Find index of input byte in table2 and put it in j */
j = 0;
while (next != table2[j][0])
j++;
if (inlen)
{
next = *inbuf++;
inlen--;
}
else
{
if (next == 0x100)
next = -1;
else
next = 0x100;
}
reg = (reg << table2[j][1]) | (table2[j][2] >> (13 - table2[j][1]));
m += table2[j][1];
while (m >= 8)
{
if (outlen >= outbuflen)
return -1;
*outbuf++ = (unsigned char)((reg >> (m - 8)) & 0xff);
outlen++;
m -= 8;
}
}
if (outlen >= outbuflen)
return -1;
*outbuf++ = (unsigned char)((reg << (8 - m)) & 0xff);
return outlen + 1;
}
STATIC int uncompress_chunk(unsigned char *inbuf, int inlen,
unsigned char *outbuf, int outbuflen)
{
int i, j, k, m = 0, outlen = 0;
unsigned reg, newdata;
if (inlen < 4)
return -1;
reg = *(inbuf + 3) | (*(inbuf + 2) << 8) | (*(inbuf + 1) << 16) |
((unsigned)*(inbuf + 0) << 24);
inbuf += 4;
inlen -= 4;
newdata = (reg >> 19) & 0x1fff;
while (1)
{
j = newdata >> 5;
if (table1[j] == 0xff)
{
i = 1;
while ((int)newdata >= table2[table3[i]][2])
i++;
j = table3[i - 1];
k = j + ((newdata - table2[j][2]) >> (13 - table2[j][1]));
if (table2[k][0] == 0x100)
break;
else
{
if (outlen >= outbuflen)
return -1;
*outbuf++ = (unsigned char)table2[k][0];
outlen++;
}
}
else
{
j = table1[j];
if (outlen >= outbuflen)
return -1;
*outbuf++ = (unsigned char)table2[j][0];
outlen++;
}
m += table2[j][1];
if (m >= 19)
{
if (m >= 8)
{
for (i = m >> 3; i; i--)
{
if (inlen)
{
reg = (reg << 8) | *inbuf++;
inlen--;
}
else
reg = reg << 8;
}
}
m = m & 7;
}
newdata = (reg >> (19 - m)) & 0x1fff;
}
return outlen;
}
/*
Reconstruct a new detail level with double resolution in the horizontal
direction from data from the previous detail level and plus new differential
data.
*/
STATIC blxdata *reconstruct_horiz(blxdata *base, blxdata *diff, unsigned rows,
unsigned cols, blxdata *out)
{
unsigned int i, j;
blxdata tmp;
/* Last column */
for (i = 0; i < rows; i++)
out[2 * (cols * i + cols - 1)] =
diff[cols * i + cols - 1] +
(((short)(base[cols * i + cols - 2] - base[cols * i + cols - 1] -
1)) >>
2);
/* Intermediate columns */
for (i = 0; i < rows; i++)
for (j = cols - 2; j > 0; j--)
out[2 * (cols * i + j)] =
diff[cols * i + j] +
(((short)(base[cols * i + j] +
2 * (base[cols * i + j - 1] -
out[2 * (cols * i + j + 1)]) -
3 * base[cols * i + j + 1] + 1)) >>
3);
/* First column */
for (i = 0; i < rows; i++)
out[2 * cols * i] =
diff[cols * i] +
(((short)(base[cols * i] - base[cols * i + 1] + 1)) >> 2);
for (i = 0; i < rows; i++)
for (j = 0; j < cols; j++)
{
tmp = base[cols * i + j] +
(((short)(out[2 * (cols * i + j)] + 1)) >> 1);
out[2 * cols * i + 2 * j + 1] = tmp - out[2 * (cols * i + j)];
out[2 * cols * i + 2 * j] = tmp;
}
return out;
}
/*
Reconstruct a new detail level with double resolution in the vertical
direction from data from the previous detail level and plus new differential
data.
*/
STATIC blxdata *reconstruct_vert(blxdata *base, blxdata *diff, unsigned rows,
unsigned cols, blxdata *out)
{
unsigned int i, j;
blxdata tmp;
/* Last row */
for (i = 0; i < cols; i++)
out[2 * cols * (rows - 1) + i] =
diff[cols * (rows - 1) + i] +
(((short)(base[cols * (rows - 2) + i] -
base[cols * (rows - 1) + i] - 1)) >>
2);
/* Intermediate rows */
for (i = 0; i < cols; i++)
for (j = rows - 2; j > 0; j--)
out[2 * cols * j + i] =
diff[cols * j + i] +
((short)((base[cols * j + i] +
2 * (base[cols * (j - 1) + i] -
out[2 * cols * (j + 1) + i]) -
3 * base[cols * (j + 1) + i] + 1)) >>
3);
/* First row */
for (i = 0; i < cols; i++)
out[i] = diff[i] + (((short)(base[i] - base[i + cols] + 1)) >> 2);
for (i = 0; i < cols; i++)
for (j = 0; j < rows; j++)
{
tmp = base[cols * j + i] +
(((short)(out[2 * cols * j + i] + 1)) >> 1);
out[cols * (2 * j + 1) + i] = tmp - out[2 * cols * j + i];
out[cols * 2 * j + i] = tmp;
}
return out;
}
/*
Inverse of reconstruct_horiz
*/
STATIC void decimate_horiz(blxdata *in, unsigned int rows, unsigned int cols,
blxdata *base, blxdata *diff)
{
unsigned int i, j;
blxdata tmp;
for (i = 0; i < rows; i++)
{
for (j = 0; j < cols; j += 2)
{
tmp = in[i * cols + j] - in[i * cols + j + 1];
diff[i * cols / 2 + j / 2] = tmp;
base[i * cols / 2 + j / 2] =
in[i * cols + j] - (((short)(tmp + 1)) >> 1);
}
}
/* First column */
for (i = 0; i < rows; i++)
{
diff[cols / 2 * i] -=
((short)(base[i * cols / 2] - base[i * cols / 2 + 1] + 1)) >> 2;
}
/* Intermediate columns */
for (i = 0; i < rows; i++)
for (j = 1; j < cols / 2 - 1; j++)
diff[cols / 2 * i + j] -=
((short)(base[cols / 2 * i + j] +
2 * (base[cols / 2 * i + j - 1] -
diff[cols / 2 * i + j + 1]) -
3 * base[cols / 2 * i + j + 1] + 1)) >>
3;
/* Last column */
for (i = 0; i < rows; i++)
diff[cols / 2 * i + cols / 2 - 1] -=
((short)(base[i * cols / 2 + cols / 2 - 2] -
base[i * cols / 2 + cols / 2 - 1] - 1)) >>
2;
}
/*
Inverse of reconstruct_vert
*/
STATIC void decimate_vert(blxdata *in, unsigned int rows, unsigned int cols,
blxdata *base, blxdata *diff)
{
unsigned int i, j;
blxdata tmp;
for (i = 0; i < rows; i += 2)
for (j = 0; j < cols; j++)
{
tmp = in[i * cols + j] - in[(i + 1) * cols + j];
diff[i / 2 * cols + j] = tmp;
base[i / 2 * cols + j] =
in[i * cols + j] - (((short)(tmp + 1)) >> 1);
}
/* First row */
for (j = 0; j < cols; j++)
diff[j] -= ((short)(base[j] - base[cols + j] + 1)) >> 2;
/* Intermediate rows */
for (i = 1; i < rows / 2 - 1; i++)
for (j = 0; j < cols; j++)
diff[cols * i + j] -= ((short)(base[cols * i + j] +
2 * (base[cols * (i - 1) + j] -
diff[cols * (i + 1) + j]) -
3 * base[cols * (i + 1) + j] + 1)) >>
3;
/* Last row */
for (j = 0; j < cols; j++)
diff[cols * (rows / 2 - 1) + j] -=
((short)(base[cols * (rows / 2 - 2) + j] -
base[cols * (rows / 2 - 1) + j] - 1)) >>
2;
}
typedef union
{
short s;
unsigned short u;
} unionshort;
static int get_short_le(const unsigned char **data)
{
/* We assume two's complement representation for this to work */
unionshort result = {0};
result.u = (unsigned short)(*(*data) | (*(*data + 1) << 8));
*data += 2;
return result.s;
}
static int get_short_be(const unsigned char **data)
{
/* We assume two's complement representation for this to work */
unionshort result = {0};
result.u = (unsigned short)(*(*data + 1) | (*(*data) << 8));
*data += 2;
return result.s;
}
static void put_short_le(short data, unsigned char **bufptr)
{
/* We assume two's complement representation for this to work */
unionshort us = {0};
us.s = data;
*(*bufptr)++ = (unsigned char)(us.u & 0xff);
*(*bufptr)++ = (unsigned char)((us.u >> 8) & 0xff);
}
static void put_short_be(short data, unsigned char **bufptr)
{
/* We assume two's complement representation for this to work */
unionshort us = {0};
us.s = data;
*(*bufptr)++ = (unsigned char)((us.u >> 8) & 0xff);
*(*bufptr)++ = (unsigned char)(us.u & 0xff);
}
static int get_unsigned_short_le(const unsigned char **data)
{
int result;
result = *(*data) | (*(*data + 1) << 8);
*data += 2;
return result;
}
static int get_unsigned_short_be(const unsigned char **data)
{
int result;
result = *(*data + 1) | (*(*data) << 8);
*data += 2;
return result;
}
static void put_unsigned_short_le(unsigned short data, unsigned char **bufptr)
{
*(*bufptr)++ = (unsigned char)(data & 0xff);
*(*bufptr)++ = (unsigned char)((data >> 8) & 0xff);
}
static void put_unsigned_short_be(unsigned short data, unsigned char **bufptr)
{
*(*bufptr)++ = (unsigned char)((data >> 8) & 0xff);
*(*bufptr)++ = (unsigned char)(data & 0xff);
}
static int get_short(blxcontext_t *ctx, const unsigned char **data)
{
if (ctx->endian == LITTLEENDIAN)
return get_short_le(data);
else
return get_short_be(data);
}
static int get_unsigned_short(blxcontext_t *ctx, const unsigned char **data)
{
if (ctx->endian == LITTLEENDIAN)
return get_unsigned_short_le(data);
else
return get_unsigned_short_be(data);
}
static void put_short(blxcontext_t *ctx, short data, unsigned char **bufptr)
{
if (ctx->endian == LITTLEENDIAN)
put_short_le(data, bufptr);
else
put_short_be(data, bufptr);
}
static void put_unsigned_short(blxcontext_t *ctx, unsigned short data,
unsigned char **bufptr)
{
if (ctx->endian == LITTLEENDIAN)
put_unsigned_short_le(data, bufptr);
else
put_unsigned_short_be(data, bufptr);
}
typedef union
{
int i;
unsigned int u;
} unionint;
static int get_int32(blxcontext_t *ctx, const unsigned char **data)
{
/* We assume two's complement representation for this to work */
unionint result = {0};
if (ctx->endian == LITTLEENDIAN)
result.u = *(*data) | (*(*data + 1) << 8) | (*(*data + 2) << 16) |
((unsigned)*(*data + 3) << 24);
else
result.u = *(*data + 3) | (*(*data + 2) << 8) | (*(*data + 1) << 16) |
((unsigned)*(*data) << 24);
*data += 4;
return result.i;
}
static void put_int32(blxcontext_t *ctx, int data, unsigned char **bufptr)
{
/* We assume two's complement representation for this to work */
unionint ui = {0};
ui.i = data;
if (ctx->endian == LITTLEENDIAN)
{
*(*bufptr)++ = (unsigned char)(ui.u & 0xff);
*(*bufptr)++ = (unsigned char)((ui.u >> 8) & 0xff);
*(*bufptr)++ = (unsigned char)((ui.u >> 16) & 0xff);
*(*bufptr)++ = (unsigned char)((ui.u >> 24) & 0xff);
}
else
{
*(*bufptr)++ = (unsigned char)((ui.u >> 24) & 0xff);
*(*bufptr)++ = (unsigned char)((ui.u >> 16) & 0xff);
*(*bufptr)++ = (unsigned char)((ui.u >> 8) & 0xff);
*(*bufptr)++ = (unsigned char)(ui.u & 0xff);
}
}
static int get_unsigned32(blxcontext_t *ctx, const unsigned char **data)
{
int result;
if (ctx->endian == LITTLEENDIAN)
result = *(*data) | (*(*data + 1) << 8) | (*(*data + 2) << 16) |
((unsigned)*(*data + 3) << 24);
else
result = *(*data + 3) | (*(*data + 2) << 8) | (*(*data + 1) << 16) |
((unsigned)*(*data) << 24);
*data += 4;
return result;
}
/* Check native endian order */
static int is_big_endian(void)
{
short int word = 0x0001;
char *byte = (char *)&word;
return (byte[0] ? 0 : 1);
}
static double doubleSWAP(double df)
{
CPL_SWAP64PTR(&df);
return df;
}
static double get_double(blxcontext_t *ctx, const unsigned char **data)
{
double result;
memcpy(&result, *data, sizeof(double));
if ((is_big_endian() && ctx->endian == LITTLEENDIAN) ||
(!is_big_endian() && ctx->endian == BIGENDIAN))
result = doubleSWAP(result);
*data += sizeof(double);
return result;
}
static void put_double(blxcontext_t *ctx, double data, unsigned char **bufptr)
{
if ((is_big_endian() && ctx->endian == LITTLEENDIAN) ||
(!is_big_endian() && ctx->endian == BIGENDIAN))
data = doubleSWAP(data);
memcpy(*bufptr, &data, sizeof(double));
*bufptr += sizeof(double);
}
static void put_cellindex_entry(blxcontext_t *ctx, struct cellindex_s *ci,
unsigned char **buffer)
{
put_int32(ctx, (int)ci->offset, buffer);
put_unsigned_short(ctx, (unsigned short)ci->datasize, buffer);
put_unsigned_short(ctx, (unsigned short)ci->compdatasize, buffer);
}
/* Transpose matrix in-place */
static void transpose(blxdata *data, int rows, int cols)
{
int i, j;
blxdata tmp;
for (i = 0; i < rows; i++)
for (j = i + 1; j < cols; j++)
{
tmp = data[i * cols + j];
data[i * cols + j] = data[j * cols + i];
data[j * cols + i] = tmp;
}
}
struct lutentry_s
{
blxdata value;
int frequency;
};
static int lutcmp(const void *aa, const void *bb)
{
const struct lutentry_s *a = aa, *b = bb;
return b->frequency - a->frequency;
}
int blx_encode_celldata(blxcontext_t *ctx, blxdata *indata, int side,
unsigned char *outbuf, CPL_UNUSED int outbufsize)
{
unsigned char *p = outbuf, *tmpdata, *coutstart, *cout = NULL;
int level, cn, coutsize, zeros;
blxdata *vdec = NULL, *vdiff = NULL, *c[4] = {NULL}, *tc1, *clut,
*indata_scaled;
struct lutentry_s lut[256];
int lutsize = 0;
int i, j;
memset(&lut, 0, sizeof(lut));
lut[0].value = 0;
*p++ = (unsigned char)(side / 32 - 4); /* Resolution */
/* Allocated memory for buffers */
indata_scaled = BLXmalloc(sizeof(blxdata) * side * side);
vdec = BLXmalloc(sizeof(blxdata) * side * side / 2);
vdiff = BLXmalloc(sizeof(blxdata) * side * side / 2);
for (cn = 0; cn < 4; cn++)
c[cn] = BLXmalloc(sizeof(blxdata) * side * side / 4);
tc1 = BLXmalloc(sizeof(blxdata) * side * side / 4);
tmpdata = BLXmalloc(5 * 4 * side * side / 4);
/* Scale indata and process undefined values*/
for (i = 0; i < side * side; i++)
{
if ((indata[i] == BLX_UNDEF) && ctx->fillundef)
indata[i] = (blxdata)ctx->fillundefval;
/* cppcheck-suppress uninitdata */
indata_scaled[i] = (blxdata)(indata[i] / ctx->zscale);
}
indata = indata_scaled;
cout = tmpdata;
for (level = 0; level < 5; level++)
{
if (ctx->debug)
{
BLXdebug1("\nlevel=%d\n", level);
}
decimate_vert(indata, side, side, vdec, vdiff);
decimate_horiz(vdec, side / 2, side, c[0], c[1]);
decimate_horiz(vdiff, side / 2, side, c[2], c[3]);
/* For some reason the matrix is transposed if the lut is used for
* vdec_hdiff */
for (i = 0; i < side / 2; i++)
for (j = 0; j < side / 2; j++)
{
tc1[j * side / 2 + i] = c[1][i * side / 2 + j];
tc1[i * side / 2 + j] = c[1][j * side / 2 + i];
}
for (cn = 1; cn < 4; cn++)
{
/* Use the possibly transposed version of c when building lut */
if (cn == 1)
clut = tc1;
else
clut = c[cn];
lutsize = 0;
coutstart = cout;
for (i = 0; i < side * side / 4; i++)
{
/* Find element in lookup table */
for (j = 0; (j < lutsize) && (lut[j].value != clut[i]); j++)
;
if (clut[i] != 0)
{
if (j == lutsize)
{
lut[lutsize].value = clut[i];
lut[lutsize].frequency = 1;
lutsize++;
if (lutsize >= 255)
break;
}
else
lut[j].frequency++;
}
}
if (lutsize < 255)
{
/* Since the Huffman table is arranged to let smaller number
occupy less bits after the compression, the lookup table is sorted on
frequency */
qsort(lut, lutsize, sizeof(struct lutentry_s), lutcmp);
zeros = 0;
for (i = 0; i < side * side / 4; i++)
{
if (clut[i] == 0)
zeros++;
if (((zeros > 0) && (clut[i] != 0)) ||
(zeros >= 0x100 - lutsize))
{
*cout++ = (unsigned char)(0x100 - zeros);
zeros = 0;
}
if (clut[i] != 0)
{
for (j = 0; (j < lutsize) && (lut[j].value != clut[i]);
j++)
;
*cout++ = (unsigned char)j;
}
}
if (zeros > 0)
*cout++ = (unsigned char)(0x100 - zeros);
}
/* Use the lookuptable only when it pays off to do do.
For some reason there cannot be lookup tables in level 4.
Otherwise Mapsend crashes. */
coutsize = (int)(cout - coutstart);
if ((lutsize < 255) &&
(coutsize + 2 * lutsize + 1 < 2 * side * side / 4) &&
(level < 4))
{
*p++ = (unsigned char)(lutsize + 1);
for (j = 0; j < lutsize; j++)
put_short_le(lut[j].value, &p);
put_short_le((short)coutsize, &p);
if (ctx->debug)
{
BLXdebug2("n=%d dlen=%d\n", lutsize + 1, coutsize);
BLXdebug0("lut={");
for (i = 0; i < lutsize; i++)
BLXdebug1("%d, ", lut[i].value);
BLXdebug0("}\n");
}
}
else
{
*p++ = 0;
cout = coutstart;
for (i = 0; i < side * side / 4; i++)
put_short(ctx, c[cn][i], &cout);
}
}
side >>= 1;
indata = c[0];
}
memcpy(p, tmpdata, cout - tmpdata);
p += cout - tmpdata;
for (i = 0; i < side * side; i++)
put_short(ctx, indata[i], &p);
*p++ = 0;
BLXfree(indata_scaled);
BLXfree(vdec);
BLXfree(vdiff);
for (cn = 0; cn < 4; cn++)
BLXfree(c[cn]);
BLXfree(tc1);
BLXfree(tmpdata);
return (int)(p - outbuf);
}
STATIC blxdata *decode_celldata(blxcontext_t *ctx, const unsigned char *inbuf,
int len, int *side, blxdata *outbuf,
int outbufsize, int overviewlevel)
{
const unsigned char *inptr = inbuf;
int resolution, l_div, level, c, n, i, j, dpos, tmp, a, value, l_index,
step, cellsize;
int baseside[12] = {0};
blxdata *base, *diff;
struct component_s linfo[MAXLEVELS][MAXCOMPONENTS];
if (len < 1)
{
BLXerror0("Cell corrupt");
return NULL;
}
resolution = *inptr++;
len--;
tmp = (resolution + 4) * 32;
for (l_div = 1; l_div < 12; l_div++)
baseside[l_div - 1] = tmp >> l_div;
if (side != NULL)
*side = tmp >> overviewlevel;
cellsize = tmp * tmp;
if (outbufsize < cellsize * (int)sizeof(blxdata))
{
BLXerror0("Cell will not fit in output buffer\n");
return NULL;
}
if (outbuf == NULL)
{
BLXerror0("outbuf is NULL");
return NULL;
}
if (ctx->debug)
{
BLXdebug0("==============================\n");
}
/* Clear level info structure */
memset(linfo, 0, sizeof(linfo));
base = BLXmalloc(sizeof(blxdata) * 2 * baseside[0] * baseside[0]);
diff = BLXmalloc(sizeof(blxdata) * 2 * baseside[0] * baseside[0]);
if (base == NULL || diff == NULL)
{
BLXerror0("Not enough memory\n");
outbuf = NULL;
goto error;
}
for (level = 0; level < 5; level++)
{
for (c = 1; c < 4; c++)
{
if (len < 1)
{
BLXerror0("Cell corrupt");
outbuf = NULL;
goto error;
}
n = *inptr++;
len--;
linfo[level][c].n = n;
if (n > 0)
{
linfo[level][c].lut = BLXmalloc(sizeof(blxdata) * (n - 1));
if (len < (int)sizeof(short) * n)
{
BLXerror0("Cell corrupt");
outbuf = NULL;
goto error;
}
for (i = 0; i < n - 1; i++)
linfo[level][c].lut[i] = (blxdata)get_short_le(&inptr);
linfo[level][c].dlen = get_short_le(&inptr);
if (linfo[level][c].dlen < 0)
{
BLXerror0("Cell corrupt");
outbuf = NULL;
goto error;
}
len -= sizeof(short) * n;
}
else
{
linfo[level][c].dlen = 0;
}
}
}
for (level = 0; level < 5; level++)
{
if (ctx->debug)
{
BLXdebug1("\nlevel=%d\n", level);
}
linfo[level][0].data =
BLXmalloc(sizeof(blxdata) * baseside[level] * baseside[level]);
if (linfo[level][0].data == NULL)
{
BLXerror0("Not enough memory\n");
outbuf = NULL;
goto error;
}
for (c = 1; c < 4; c++)
{
if (ctx->debug)
{
BLXdebug2("n=%d dlen=%d\n", linfo[level][c].n,
linfo[level][c].dlen);
BLXdebug0("lut={");
for (i = 0; i < linfo[level][c].n - 1; i++)
BLXdebug1("%d, ", linfo[level][c].lut[i]);
BLXdebug0("}\n");
}
linfo[level][c].data =
BLXmalloc(sizeof(blxdata) * baseside[level] * baseside[level]);
if (linfo[level][c].data == NULL)
{
BLXerror0("Not enough memory\n");
outbuf = NULL;
goto error;
}
if (linfo[level][c].n == 0)
{
if (len <
(int)sizeof(short) * baseside[level] * baseside[level])
{
BLXerror0("Cell corrupt");
outbuf = NULL;
goto error;
}
for (i = 0; i < baseside[level] * baseside[level]; i++)
linfo[level][c].data[i] = (blxdata)get_short(ctx, &inptr);
len -= sizeof(short) * baseside[level] * baseside[level];
}
else
{
dpos = 0;
if (len < linfo[level][c].dlen)
{
BLXerror0("Cell corrupt");
outbuf = NULL;
goto error;
}
for (i = 0; i < linfo[level][c].dlen; i++)
{
unsigned char v = *inptr++;
if (v >= linfo[level][c].n - 1)
{
if (dpos + 256 - v > baseside[level] * baseside[level])
{
BLXerror0("Cell corrupt\n");
outbuf = NULL;
goto error;
}
/* coverity[tainted_data] */
for (j = 0; j < 256 - v; j++)
linfo[level][c].data[dpos++] = 0;
}