* Copyright (c) 1988-1997 Sam Leffler
* Copyright (c) 1991-1997 Silicon Graphics, Inc.
*
- * Permission to use, copy, modify, distribute, and sell this software and
+ * Permission to use, copy, modify, distribute, and sell this software and
* its documentation for any purpose is hereby granted without fee, provided
* that (i) the above copyright notices and this permission notice appear in
* all copies of the software and related documentation, and (ii) the names of
* Sam Leffler and Silicon Graphics may not be used in any advertising or
* publicity relating to the software without the specific, prior written
* permission of Sam Leffler and Silicon Graphics.
- *
- * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
- * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
- * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
- *
+ *
+ * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
+ * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
+ *
* IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
* ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
* OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
- * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
- * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
+ * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
* OF THIS SOFTWARE.
*/
*
* The original Berkeley copyright notice appears below in its entirety.
*/
-/* Watcom C++ (or its make utility) doesn't like long filenames */
-#ifdef __WATCOMC__
-#include "tif_pred.h"
-#else
#include "tif_predict.h"
-#endif
#include <assert.h>
#include <stdio.h>
#define lzw_nextdata base.nextdata
#define lzw_nextbits base.nextbits
+/*
+ * Encoding-specific state.
+ */
+typedef uint16 hcode_t; /* codes fit in 16 bits */
+
/*
* Decoding-specific state.
*/
u_char firstchar; /* first token of string */
} code_t;
-typedef int (LINKAGEMODE *decodeFunc)(TIFF*, tidata_t, tsize_t, tsample_t);
+typedef int (*decodeFunc)(TIFF*, tidata_t, tsize_t, tsample_t);
typedef struct {
LZWBaseState base;
+
+ /* Decoding specific data */
long dec_nbitsmask; /* lzw_nbits 1 bits, right adjusted */
long dec_restart; /* restart count */
#ifdef LZW_CHECKEOS
code_t* dec_free_entp; /* next free entry */
code_t* dec_maxcodep; /* max available entry */
code_t* dec_codetab; /* kept separate for small machines */
-} LZWDecodeState;
-
-/*
- * Encoding-specific state.
- */
-typedef uint16 hcode_t; /* codes fit in 16 bits */
-typedef struct {
- long hash;
- hcode_t code;
-} hash_t;
-
-typedef struct {
- LZWBaseState base;
- int enc_oldcode; /* last code encountered */
- long enc_checkpoint; /* point at which to clear table */
-#define CHECK_GAP 10000 /* enc_ratio check interval */
- long enc_ratio; /* current compression ratio */
- long enc_incount; /* (input) data bytes encoded */
- long enc_outcount; /* encoded (output) bytes */
- tidata_t enc_rawlimit; /* bound on tif_rawdata buffer */
- hash_t* enc_hashtab; /* kept separate for small machines */
-} LZWEncodeState;
+} LZWCodecState;
#define LZWState(tif) ((LZWBaseState*) (tif)->tif_data)
-#define DecoderState(tif) ((LZWDecodeState*) LZWState(tif))
-#define EncoderState(tif) ((LZWEncodeState*) LZWState(tif))
+#define DecoderState(tif) ((LZWCodecState*) LZWState(tif))
-static int LINKAGEMODE LZWDecode(TIFF*, tidata_t, tsize_t, tsample_t);
+static int LZWDecode(TIFF*, tidata_t, tsize_t, tsample_t);
#ifdef LZW_COMPAT
-static int LINKAGEMODE LZWDecodeCompat(TIFF*, tidata_t, tsize_t, tsample_t);
+static int LZWDecodeCompat(TIFF*, tidata_t, tsize_t, tsample_t);
#endif
-static void cl_hash(LZWEncodeState*);
/*
* LZW Decoder.
static int
LZWSetupDecode(TIFF* tif)
{
- LZWDecodeState* sp = DecoderState(tif);
- static const char module[] = " LZWSetupDecode";
+ LZWCodecState* sp = DecoderState(tif);
+ static const char module[] = "LZWSetupDecode";
int code;
assert(sp != NULL);
+
if (sp->dec_codetab == NULL) {
sp->dec_codetab = (code_t*)_TIFFmalloc(CSIZE*sizeof (code_t));
if (sp->dec_codetab == NULL) {
/*
* Pre-load the table.
*/
- for (code = 255; code >= 0; code--) {
- sp->dec_codetab[code].value = code;
- sp->dec_codetab[code].firstchar = code;
- sp->dec_codetab[code].length = 1;
- sp->dec_codetab[code].next = NULL;
- }
+ code = 255;
+ do {
+ sp->dec_codetab[code].value = (u_char) code;
+ sp->dec_codetab[code].firstchar = (u_char) code;
+ sp->dec_codetab[code].length = 1;
+ sp->dec_codetab[code].next = NULL;
+ } while (code--);
}
return (1);
}
static int
LZWPreDecode(TIFF* tif, tsample_t s)
{
- LZWDecodeState *sp = DecoderState(tif);
+ LZWCodecState *sp = DecoderState(tif);
(void) s;
assert(sp != NULL);
static int
LZWDecode(TIFF* tif, tidata_t op0, tsize_t occ0, tsample_t s)
{
- LZWDecodeState *sp = DecoderState(tif);
+ LZWCodecState *sp = DecoderState(tif);
char *op = (char*) op0;
long occ = (long) occ0;
char *tp;
--tp;
t = codep->value;
codep = codep->next;
- *tp = t;
+ *tp = (char) t;
} while (--residue && codep);
sp->dec_restart = 0;
}
NextCode(tif, sp, bp, code, GetNextCode);
if (code == CODE_EOI)
break;
- *op++ = code, occ--;
+ *op++ = (char)code, occ--;
oldcodep = sp->dec_codetab + code;
continue;
}
/*
* Add the new entry to the code table.
*/
- assert(&sp->dec_codetab[0] <= free_entp && free_entp < &sp->dec_codetab[CSIZE]);
+ if (free_entp < &sp->dec_codetab[0] ||
+ free_entp >= &sp->dec_codetab[CSIZE]) {
+ TIFFError(tif->tif_name,
+ "LZWDecode: Corrupted LZW table at scanline %d",
+ tif->tif_row);
+ return (0);
+ }
+
free_entp->next = oldcodep;
+ if (free_entp->next < &sp->dec_codetab[0] ||
+ free_entp->next >= &sp->dec_codetab[CSIZE]) {
+ TIFFError(tif->tif_name,
+ "LZWDecode: Corrupted LZW table at scanline %d",
+ tif->tif_row);
+ return (0);
+ }
free_entp->firstchar = free_entp->next->firstchar;
free_entp->length = free_entp->next->length+1;
free_entp->value = (codep < free_entp) ?
* Code maps to a string, copy string
* value to output (written in reverse).
*/
+ if(codep->length == 0) {
+ TIFFError(tif->tif_name,
+ "LZWDecode: Wrong length of decoded string: "
+ "data probably corrupted at scanline %d",
+ tif->tif_row);
+ return (0);
+ }
if (codep->length > occ) {
/*
* String is too long for decode buffer,
--tp;
t = codep->value;
codep = codep->next;
- *tp = t;
+ *tp = (char) t;
} while (codep && tp > op);
if (codep) {
codeLoop(tif);
}
op += len, occ -= len;
} else
- *op++ = code, occ--;
+ *op++ = (char)code, occ--;
}
tif->tif_rawcp = (tidata_t) bp;
nextbits -= nbits; \
}
-static int LINKAGEMODE
+static int
LZWDecodeCompat(TIFF* tif, tidata_t op0, tsize_t occ0, tsample_t s)
{
- LZWDecodeState *sp = DecoderState(tif);
+ LZWCodecState *sp = DecoderState(tif);
char *op = (char*) op0;
long occ = (long) occ0;
char *tp;
NextCode(tif, sp, bp, code, GetNextCodeCompat);
if (code == CODE_EOI)
break;
- *op++ = code, occ--;
+ *op++ = (char) code, occ--;
oldcodep = sp->dec_codetab + code;
continue;
}
/*
* Add the new entry to the code table.
*/
- assert(&sp->dec_codetab[0] <= free_entp && free_entp < &sp->dec_codetab[CSIZE]);
+ if (free_entp < &sp->dec_codetab[0] ||
+ free_entp >= &sp->dec_codetab[CSIZE]) {
+ TIFFError(tif->tif_name,
+ "LZWDecodeCompat: Corrupted LZW table at scanline %d",
+ tif->tif_row);
+ return (0);
+ }
+
free_entp->next = oldcodep;
+ if (free_entp->next < &sp->dec_codetab[0] ||
+ free_entp->next >= &sp->dec_codetab[CSIZE]) {
+ TIFFError(tif->tif_name,
+ "LZWDecodeCompat: Corrupted LZW table at scanline %d",
+ tif->tif_row);
+ return (0);
+ }
free_entp->firstchar = free_entp->next->firstchar;
free_entp->length = free_entp->next->length+1;
free_entp->value = (codep < free_entp) ?
* Code maps to a string, copy string
* value to output (written in reverse).
*/
+ if(codep->length == 0) {
+ TIFFError(tif->tif_name,
+ "LZWDecodeCompat: Wrong length of decoded "
+ "string: data probably corrupted at scanline %d",
+ tif->tif_row);
+ return (0);
+ }
if (codep->length > occ) {
/*
* String is too long for decode buffer,
*--tp = codep->value;
} while( (codep = codep->next) != NULL);
} else
- *op++ = code, occ--;
+ *op++ = (char) code, occ--;
}
tif->tif_rawcp = (tidata_t) bp;
- sp->lzw_nbits = nbits;
+ sp->lzw_nbits = (u_short) nbits;
sp->lzw_nextdata = nextdata;
sp->lzw_nextbits = nextbits;
sp->dec_nbitsmask = nbitsmask;
}
#endif /* LZW_COMPAT */
-/*
- * LZW Encoding.
- */
-
-static int
-LZWSetupEncode(TIFF* tif)
-{
- LZWEncodeState* sp = EncoderState(tif);
- static const char module[] = "LZWSetupEncode";
-
- assert(sp != NULL);
- sp->enc_hashtab = (hash_t*) _TIFFmalloc(HSIZE*sizeof (hash_t));
- if (sp->enc_hashtab == NULL) {
- TIFFError(module, "No space for LZW hash table");
- return (0);
- }
- return (1);
-}
-
-/*
- * Reset encoding state at the start of a strip.
- */
-static int
-LZWPreEncode(TIFF* tif, tsample_t s)
-{
- LZWEncodeState *sp = EncoderState(tif);
-
- (void) s;
- assert(sp != NULL);
- sp->lzw_nbits = BITS_MIN;
- sp->lzw_maxcode = MAXCODE(BITS_MIN);
- sp->lzw_free_ent = CODE_FIRST;
- sp->lzw_nextbits = 0;
- sp->lzw_nextdata = 0;
- sp->enc_checkpoint = CHECK_GAP;
- sp->enc_ratio = 0;
- sp->enc_incount = 0;
- sp->enc_outcount = 0;
- /*
- * The 4 here insures there is space for 2 max-sized
- * codes in LZWEncode and LZWPostDecode.
- */
- sp->enc_rawlimit = tif->tif_rawdata + tif->tif_rawdatasize-1 - 4;
- cl_hash(sp); /* clear hash table */
- sp->enc_oldcode = (hcode_t) -1; /* generates CODE_CLEAR in LZWEncode */
- return (1);
-}
-#define CALCRATIO(sp, rat) { \
- if (incount > 0x007fffff) { /* NB: shift will overflow */\
- rat = outcount >> 8; \
- rat = (rat == 0 ? 0x7fffffff : incount/rat); \
- } else \
- rat = (incount<<8) / outcount; \
-}
-#define PutNextCode(op, c) { \
- nextdata = (nextdata << nbits) | c; \
- nextbits += nbits; \
- *op++ = (u_char)(nextdata >> (nextbits-8)); \
- nextbits -= 8; \
- if (nextbits >= 8) { \
- *op++ = (u_char)(nextdata >> (nextbits-8)); \
- nextbits -= 8; \
- } \
- outcount += nbits; \
-}
-/*
- * Encode a chunk of pixels.
- *
- * Uses an open addressing double hashing (no chaining) on the
- * prefix code/next character combination. We do a variant of
- * Knuth's algorithm D (vol. 3, sec. 6.4) along with G. Knott's
- * relatively-prime secondary probe. Here, the modular division
- * first probe is gives way to a faster exclusive-or manipulation.
- * Also do block compression with an adaptive reset, whereby the
- * code table is cleared when the compression ratio decreases,
- * but after the table fills. The variable-length output codes
- * are re-sized at this point, and a CODE_CLEAR is generated
- * for the decoder.
- */
-static int LINKAGEMODE
-LZWEncode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
-{
- register LZWEncodeState *sp = EncoderState(tif);
- register long fcode;
- register hash_t *hp;
- register int h, c;
- hcode_t ent;
- long disp;
- long incount, outcount, checkpoint;
- long nextdata, nextbits;
- int free_ent, maxcode, nbits;
- tidata_t op, limit;
-
- (void) s;
- if (sp == NULL)
- return (0);
- /*
- * Load local state.
- */
- incount = sp->enc_incount;
- outcount = sp->enc_outcount;
- checkpoint = sp->enc_checkpoint;
- nextdata = sp->lzw_nextdata;
- nextbits = sp->lzw_nextbits;
- free_ent = sp->lzw_free_ent;
- maxcode = sp->lzw_maxcode;
- nbits = sp->lzw_nbits;
- op = tif->tif_rawcp;
- limit = sp->enc_rawlimit;
- ent = sp->enc_oldcode;
-
- if (ent == (hcode_t) -1 && cc > 0) {
- /*
- * NB: This is safe because it can only happen
- * at the start of a strip where we know there
- * is space in the data buffer.
- */
- PutNextCode(op, CODE_CLEAR);
- ent = *bp++; cc--; incount++;
- }
- while (cc > 0) {
- c = *bp++; cc--; incount++;
- fcode = ((long)c << BITS_MAX) + ent;
- h = (c << HSHIFT) ^ ent; /* xor hashing */
-#ifdef _WINDOWS
- /*
- * Check hash index for an overflow.
- */
- if (h >= HSIZE)
- h -= HSIZE;
-#endif
- hp = &sp->enc_hashtab[h];
- if (hp->hash == fcode) {
- ent = hp->code;
- continue;
- }
- if (hp->hash >= 0) {
- /*
- * Primary hash failed, check secondary hash.
- */
- disp = HSIZE - h;
- if (h == 0)
- disp = 1;
- do {
- /*
- * Avoid pointer arithmetic 'cuz of
- * wraparound problems with segments.
- */
- if ((h -= disp) < 0)
- h += HSIZE;
- hp = &sp->enc_hashtab[h];
- if (hp->hash == fcode) {
- ent = hp->code;
- goto hit;
- }
- } while (hp->hash >= 0);
- }
- /*
- * New entry, emit code and add to table.
- */
- /*
- * Verify there is space in the buffer for the code
- * and any potential Clear code that might be emitted
- * below. The value of limit is setup so that there
- * are at least 4 bytes free--room for 2 codes.
- */
- if (op > limit) {
- tif->tif_rawcc = (tsize_t)(op - tif->tif_rawdata);
- TIFFFlushData1(tif);
- op = tif->tif_rawdata;
- }
- PutNextCode(op, ent);
- ent = c;
- hp->code = free_ent++;
- hp->hash = fcode;
- if (free_ent == CODE_MAX-1) {
- /* table is full, emit clear code and reset */
- cl_hash(sp);
- sp->enc_ratio = 0;
- incount = 0;
- outcount = 0;
- free_ent = CODE_FIRST;
- PutNextCode(op, CODE_CLEAR);
- nbits = BITS_MIN;
- maxcode = MAXCODE(BITS_MIN);
- } else {
- /*
- * If the next entry is going to be too big for
- * the code size, then increase it, if possible.
- */
- if (free_ent > maxcode) {
- nbits++;
- assert(nbits <= BITS_MAX);
- maxcode = (int) MAXCODE(nbits);
- } else if (incount >= checkpoint) {
- long rat;
- /*
- * Check compression ratio and, if things seem
- * to be slipping, clear the hash table and
- * reset state. The compression ratio is a
- * 24+8-bit fractional number.
- */
- checkpoint = incount+CHECK_GAP;
- CALCRATIO(sp, rat);
- if (rat <= sp->enc_ratio) {
- cl_hash(sp);
- sp->enc_ratio = 0;
- incount = 0;
- outcount = 0;
- free_ent = CODE_FIRST;
- PutNextCode(op, CODE_CLEAR);
- nbits = BITS_MIN;
- maxcode = MAXCODE(BITS_MIN);
- } else
- sp->enc_ratio = rat;
- }
- }
- hit:
- ;
- }
-
- /*
- * Restore global state.
- */
- sp->enc_incount = incount;
- sp->enc_outcount = outcount;
- sp->enc_checkpoint = checkpoint;
- sp->enc_oldcode = ent;
- sp->lzw_nextdata = nextdata;
- sp->lzw_nextbits = nextbits;
- sp->lzw_free_ent = free_ent;
- sp->lzw_maxcode = maxcode;
- sp->lzw_nbits = nbits;
- tif->tif_rawcp = op;
- return (1);
-}
-
-/*
- * Finish off an encoded strip by flushing the last
- * string and tacking on an End Of Information code.
- */
-static int
-LZWPostEncode(TIFF* tif)
-{
- register LZWEncodeState *sp = EncoderState(tif);
- tidata_t op = tif->tif_rawcp;
- long nextbits = sp->lzw_nextbits;
- long nextdata = sp->lzw_nextdata;
- long outcount = sp->enc_outcount;
- int nbits = sp->lzw_nbits;
-
- if (op > sp->enc_rawlimit) {
- tif->tif_rawcc = (tsize_t)(op - tif->tif_rawdata);
- TIFFFlushData1(tif);
- op = tif->tif_rawdata;
- }
- if (sp->enc_oldcode != (hcode_t) -1) {
- PutNextCode(op, sp->enc_oldcode);
- sp->enc_oldcode = (hcode_t) -1;
- }
- PutNextCode(op, CODE_EOI);
- if (nextbits > 0)
- *op++ = (u_char)(nextdata << (8-nextbits));
- tif->tif_rawcc = (tsize_t)(op - tif->tif_rawdata);
- return (1);
-}
-
-/*
- * Reset encoding hash table.
- */
static void
-cl_hash(LZWEncodeState* sp)
+LZWCleanup(TIFF* tif)
{
- register hash_t *hp = &sp->enc_hashtab[HSIZE-1];
- register long i = HSIZE-8;
-
- do {
- i -= 8;
- hp[-7].hash = -1;
- hp[-6].hash = -1;
- hp[-5].hash = -1;
- hp[-4].hash = -1;
- hp[-3].hash = -1;
- hp[-2].hash = -1;
- hp[-1].hash = -1;
- hp[ 0].hash = -1;
- hp -= 8;
- } while (i >= 0);
- for (i += 8; i > 0; i--, hp--)
- hp->hash = -1;
+ if (tif->tif_data) {
+ if (DecoderState(tif)->dec_codetab)
+ _TIFFfree(DecoderState(tif)->dec_codetab);
+ _TIFFfree(tif->tif_data);
+ tif->tif_data = NULL;
+ }
}
-static void
-LZWCleanup(TIFF* tif)
+static int
+LZWSetupEncode(TIFF* tif)
{
- if (tif->tif_data) {
- if (tif->tif_mode == O_RDONLY) {
- if (DecoderState(tif)->dec_codetab)
- _TIFFfree(DecoderState(tif)->dec_codetab);
- } else {
- if (EncoderState(tif)->enc_hashtab)
- _TIFFfree(EncoderState(tif)->enc_hashtab);
- }
- _TIFFfree(tif->tif_data);
- tif->tif_data = NULL;
- }
+ TIFFError(tif->tif_name,
+ "LZW compression is not available to due to Unisys patent enforcement");
+ return (0);
}
int
TIFFInitLZW(TIFF* tif, int scheme)
{
assert(scheme == COMPRESSION_LZW);
+
/*
* Allocate state block so tag methods have storage to record values.
*/
- if (tif->tif_mode == O_RDONLY) {
- tif->tif_data = (tidata_t) _TIFFmalloc(sizeof (LZWDecodeState));
- if (tif->tif_data == NULL)
- goto bad;
- DecoderState(tif)->dec_codetab = NULL;
- DecoderState(tif)->dec_decode = NULL;
- } else {
- tif->tif_data = (tidata_t) _TIFFmalloc(sizeof (LZWEncodeState));
- if (tif->tif_data == NULL)
- goto bad;
- EncoderState(tif)->enc_hashtab = NULL;
- }
+ tif->tif_data = (tidata_t) _TIFFmalloc(sizeof (LZWCodecState));
+ if (tif->tif_data == NULL)
+ goto bad;
+ DecoderState(tif)->dec_codetab = NULL;
+ DecoderState(tif)->dec_decode = NULL;
+
/*
* Install codec methods.
*/
+ tif->tif_setupencode = LZWSetupEncode;
tif->tif_setupdecode = LZWSetupDecode;
tif->tif_predecode = LZWPreDecode;
tif->tif_decoderow = LZWDecode;
tif->tif_decodestrip = LZWDecode;
tif->tif_decodetile = LZWDecode;
- tif->tif_setupencode = LZWSetupEncode;
- tif->tif_preencode = LZWPreEncode;
- tif->tif_postencode = LZWPostEncode;
- tif->tif_encoderow = LZWEncode;
- tif->tif_encodestrip = LZWEncode;
- tif->tif_encodetile = LZWEncode;
tif->tif_cleanup = LZWCleanup;
+
/*
* Setup predictor setup.
*/
(void) TIFFPredictorInit(tif);
+
return (1);
+
bad:
TIFFError("TIFFInitLZW", "No space for LZW state block");
return (0);
projects / wxWidgets.git / blobdiff