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-rw-r--r--pdf/xpdf/Stream.cc1774
1 files changed, 1018 insertions, 756 deletions
diff --git a/pdf/xpdf/Stream.cc b/pdf/xpdf/Stream.cc
index 9777940..0d19d4d 100644
--- a/pdf/xpdf/Stream.cc
+++ b/pdf/xpdf/Stream.cc
@@ -6,11 +6,12 @@
//
//========================================================================
-#ifdef __GNUC__
+#include <aconf.h>
+
+#ifdef USE_GCC_PRAGMAS
#pragma implementation
#endif
-#include <aconf.h>
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
@@ -28,6 +29,7 @@
#include "Decrypt.h"
#endif
#include "Stream.h"
+#include "JBIG2Stream.h"
#include "Stream-CCITT.h"
#ifdef __DJGPP__
@@ -35,9 +37,6 @@ static GBool setDJSYSFLAGS = gFalse;
#endif
#ifdef VMS
-#if (__VMS_VER < 70000000)
-extern "C" int unlink(char *filename);
-#endif
#ifdef __GNUC__
#define SEEK_SET 0
#define SEEK_CUR 1
@@ -45,10 +44,6 @@ extern "C" int unlink(char *filename);
#endif
#endif
-#ifdef MACOS
-#include "StuffItEngineLib.h"
-#endif
-
//------------------------------------------------------------------------
// Stream (base class)
//------------------------------------------------------------------------
@@ -145,7 +140,7 @@ Stream *Stream::makeFilter(char *name, Stream *str, Object *params) {
int encoding;
GBool endOfLine, byteAlign, endOfBlock, black;
int columns, rows;
- Object obj;
+ Object globals, obj;
if (!strcmp(name, "ASCIIHexDecode") || !strcmp(name, "AHx")) {
str = new ASCIIHexStream(str);
@@ -255,6 +250,12 @@ Stream *Stream::makeFilter(char *name, Stream *str, Object *params) {
obj.free();
}
str = new FlateStream(str, pred, columns, colors, bits);
+ } else if (!strcmp(name, "JBIG2Decode")) {
+ if (params->isDict()) {
+ params->dictLookup("JBIG2Globals", &globals);
+ }
+ str = new JBIG2Stream(str, &globals);
+ globals.free();
} else {
error(getPos(), "Unknown filter '%s'", name);
str = new EOFStream(str);
@@ -338,51 +339,54 @@ void ImageStream::reset() {
}
GBool ImageStream::getPixel(Guchar *pix) {
+ int i;
+
+ if (imgIdx >= nVals) {
+ getLine();
+ imgIdx = 0;
+ }
+ for (i = 0; i < nComps; ++i) {
+ pix[i] = imgLine[imgIdx++];
+ }
+ return gTrue;
+}
+
+Guchar *ImageStream::getLine() {
Gulong buf, bitMask;
int bits;
int c;
int i;
- if (imgIdx >= nVals) {
-
- // read one line of image pixels
- if (nBits == 1) {
- for (i = 0; i < nVals; i += 8) {
- c = str->getChar();
- imgLine[i+0] = (Guchar)((c >> 7) & 1);
- imgLine[i+1] = (Guchar)((c >> 6) & 1);
- imgLine[i+2] = (Guchar)((c >> 5) & 1);
- imgLine[i+3] = (Guchar)((c >> 4) & 1);
- imgLine[i+4] = (Guchar)((c >> 3) & 1);
- imgLine[i+5] = (Guchar)((c >> 2) & 1);
- imgLine[i+6] = (Guchar)((c >> 1) & 1);
- imgLine[i+7] = (Guchar)(c & 1);
- }
- } else if (nBits == 8) {
- for (i = 0; i < nVals; ++i) {
- imgLine[i] = str->getChar();
- }
- } else {
- bitMask = (1 << nBits) - 1;
- buf = 0;
- bits = 0;
- for (i = 0; i < nVals; ++i) {
- if (bits < nBits) {
- buf = (buf << 8) | (str->getChar() & 0xff);
- bits += 8;
- }
- imgLine[i] = (Guchar)((buf >> (bits - nBits)) & bitMask);
- bits -= nBits;
+ if (nBits == 1) {
+ for (i = 0; i < nVals; i += 8) {
+ c = str->getChar();
+ imgLine[i+0] = (Guchar)((c >> 7) & 1);
+ imgLine[i+1] = (Guchar)((c >> 6) & 1);
+ imgLine[i+2] = (Guchar)((c >> 5) & 1);
+ imgLine[i+3] = (Guchar)((c >> 4) & 1);
+ imgLine[i+4] = (Guchar)((c >> 3) & 1);
+ imgLine[i+5] = (Guchar)((c >> 2) & 1);
+ imgLine[i+6] = (Guchar)((c >> 1) & 1);
+ imgLine[i+7] = (Guchar)(c & 1);
+ }
+ } else if (nBits == 8) {
+ for (i = 0; i < nVals; ++i) {
+ imgLine[i] = str->getChar();
+ }
+ } else {
+ bitMask = (1 << nBits) - 1;
+ buf = 0;
+ bits = 0;
+ for (i = 0; i < nVals; ++i) {
+ if (bits < nBits) {
+ buf = (buf << 8) | (str->getChar() & 0xff);
+ bits += 8;
}
+ imgLine[i] = (Guchar)((buf >> (bits - nBits)) & bitMask);
+ bits -= nBits;
}
-
- // reset to start of line
- imgIdx = 0;
}
-
- for (i = 0; i < nComps; ++i)
- pix[i] = imgLine[imgIdx++];
- return gTrue;
+ return imgLine;
}
void ImageStream::skipLine() {
@@ -577,7 +581,10 @@ Stream *FileStream::makeSubStream(Guint startA, GBool limitedA,
}
void FileStream::reset() {
-#if HAVE_FSEEK64
+#if HAVE_FSEEKO
+ savePos = (Guint)ftello(f);
+ fseeko(f, start, SEEK_SET);
+#elif HAVE_FSEEK64
savePos = (Guint)ftell64(f);
fseek64(f, start, SEEK_SET);
#else
@@ -595,7 +602,9 @@ void FileStream::reset() {
void FileStream::close() {
if (saved) {
-#if HAVE_FSEEK64
+#if HAVE_FSEEKO
+ fseeko(f, savePos, SEEK_SET);
+#elif HAVE_FSEEK64
fseek64(f, savePos, SEEK_SET);
#else
fseek(f, savePos, SEEK_SET);
@@ -639,14 +648,19 @@ void FileStream::setPos(Guint pos, int dir) {
Guint size;
if (dir >= 0) {
-#if HAVE_FSEEK64
+#if HAVE_FSEEKO
+ fseeko(f, pos, SEEK_SET);
+#elif HAVE_FSEEK64
fseek64(f, pos, SEEK_SET);
#else
fseek(f, pos, SEEK_SET);
#endif
bufPos = pos;
} else {
-#if HAVE_FSEEK64
+#if HAVE_FSEEKO
+ fseeko(f, 0, SEEK_END);
+ size = (Guint)ftello(f);
+#elif HAVE_FSEEK64
fseek64(f, 0, SEEK_END);
size = (Guint)ftell64(f);
#else
@@ -659,7 +673,10 @@ void FileStream::setPos(Guint pos, int dir) {
//~ work around a bug in cygwin's implementation of fseek
rewind(f);
#endif
-#if HAVE_FSEEK64
+#if HAVE_FSEEKO
+ fseeko(f, -(int)pos, SEEK_END);
+ bufPos = (Guint)ftello(f);
+#elif HAVE_FSEEK64
fseek64(f, -(int)pos, SEEK_END);
bufPos = (Guint)ftell64(f);
#else
@@ -969,21 +986,12 @@ LZWStream::LZWStream(Stream *strA, int predictor, int columns, int colors,
pred = NULL;
}
early = earlyA;
- zPipe = NULL;
- bufPtr = bufEnd = buf;
+ eof = gFalse;
+ inputBits = 0;
+ clearTable();
}
LZWStream::~LZWStream() {
- if (zPipe) {
-#ifdef HAVE_POPEN
- pclose(zPipe);
-#else
- fclose(zPipe);
-#endif
- zPipe = NULL;
- unlink(zName->getCString());
- delete zName;
- }
if (pred) {
delete pred;
}
@@ -994,264 +1002,142 @@ int LZWStream::getChar() {
if (pred) {
return pred->getChar();
}
- return (bufPtr >= bufEnd && !fillBuf()) ? EOF : (*bufPtr++ & 0xff);
+ if (eof) {
+ return EOF;
+ }
+ if (seqIndex >= seqLength) {
+ if (!processNextCode()) {
+ return EOF;
+ }
+ }
+ return seqBuf[seqIndex++];
}
int LZWStream::lookChar() {
if (pred) {
return pred->lookChar();
}
- return (bufPtr >= bufEnd && !fillBuf()) ? EOF : (*bufPtr & 0xff);
+ if (eof) {
+ return EOF;
+ }
+ if (seqIndex >= seqLength) {
+ if (!processNextCode()) {
+ return EOF;
+ }
+ }
+ return seqBuf[seqIndex];
}
int LZWStream::getRawChar() {
- return (bufPtr >= bufEnd && !fillBuf()) ? EOF : (*bufPtr++ & 0xff);
+ if (eof) {
+ return EOF;
+ }
+ if (seqIndex >= seqLength) {
+ if (!processNextCode()) {
+ return EOF;
+ }
+ }
+ return seqBuf[seqIndex++];
}
void LZWStream::reset() {
- FILE *f;
- GString *zCmd;
+ str->reset();
+ eof = gFalse;
+ inputBits = 0;
+ clearTable();
+}
- //----- close old LZW stream
- if (zPipe) {
-#ifdef HAVE_POPEN
- pclose(zPipe);
-#else
- fclose(zPipe);
-#endif
- zPipe = NULL;
- unlink(zName->getCString());
- delete zName;
- }
+GBool LZWStream::processNextCode() {
+ int code;
+ int nextLength;
+ int i, j;
- //----- tell Delorie runtime to spawn a new instance of COMMAND.COM
- // to run gzip
-#if __DJGPP__
- if (!setDJSYSFLAGS) {
- setenv("DJSYSFLAGS", "0x0002", 0);
- setDJSYSFLAGS = gTrue;
+ // check for EOF
+ if (eof) {
+ return gFalse;
}
-#endif
- //----- create the .Z file
- if (!openTempFile(&zName, &f, "wb", ".Z")) {
- error(getPos(), "Couldn't create temporary file for LZW stream");
- return;
- }
- dumpFile(f);
- fclose(f);
-
- //----- execute uncompress / gzip
- zCmd = new GString(uncompressCmd);
- zCmd->append(' ');
- zCmd->append(zName);
-#if defined(MACOS)
- long magicCookie;
- // first we open the engine up
- OSErr err = OpenSITEngine(kUseExternalEngine, &magicCookie);
- // if we found it - let's use it!
- if (!err && magicCookie) {
- // make sure we have the correct version of the Engine
- if (GetSITEngineVersion(magicCookie) >= kFirstSupportedEngine) {
- FSSpec myFSS;
- Str255 pName;
- strcpy((char *)pName, zName->getCString());
- c2pstr((char *)pName);
- FSMakeFSSpec(0, 0, pName, &myFSS);
- short ftype = DetermineFileType(magicCookie, &myFSS);
- OSErr expandErr = ExpandFSSpec(magicCookie, ftype, &myFSS,
- NULL, NULL, kCreateFolderNever,
- kDeleteOriginal, kTextConvertSmart);
- }
- }
-#elif defined(HAVE_POPEN)
- if (!(zPipe = popen(zCmd->getCString(), POPEN_READ_MODE))) {
- error(getPos(), "Couldn't popen '%s'", zCmd->getCString());
- unlink(zName->getCString());
- delete zName;
- return;
- }
-#else // HAVE_POPEN
- if (!executeCommand(zCmd->getCString())) {
- error(getPos(), "Couldn't execute '%s'", zCmd->getCString());
- unlink(zName->getCString());
- delete zName;
- return;
+ // check for eod and clear-table codes
+ start:
+ code = getCode();
+ if (code == EOF || code == 257) {
+ eof = gTrue;
+ return gFalse;
}
- zName->del(zName->getLength() - 2, 2);
- if (!(zPipe = fopen(zName->getCString(), "rb"))) {
- error(getPos(), "Couldn't open uncompress file '%s'", zName->getCString());
- unlink(zName->getCString());
- delete zName;
- return;
+ if (code == 256) {
+ clearTable();
+ goto start;
+ }
+ if (nextCode >= 4097) {
+ error(getPos(), "Bad LZW stream - expected clear-table code");
+ clearTable();
+ }
+
+ // process the next code
+ nextLength = seqLength + 1;
+ if (code < 256) {
+ seqBuf[0] = code;
+ seqLength = 1;
+ } else if (code < nextCode) {
+ seqLength = table[code].length;
+ for (i = seqLength - 1, j = code; i > 0; --i) {
+ seqBuf[i] = table[j].tail;
+ j = table[j].head;
+ }
+ seqBuf[0] = j;
+ } else if (code == nextCode) {
+ seqBuf[seqLength] = newChar;
+ ++seqLength;
+ } else {
+ error(getPos(), "Bad LZW stream - unexpected code");
+ eof = gTrue;
+ return gFalse;
}
-#endif // HAVE_POPEN
-
- //----- clean up
- delete zCmd;
+ newChar = seqBuf[0];
+ if (first) {
+ first = gFalse;
+ } else {
+ table[nextCode].length = nextLength;
+ table[nextCode].head = prevCode;
+ table[nextCode].tail = newChar;
+ ++nextCode;
+ if (nextCode + early == 512)
+ nextBits = 10;
+ else if (nextCode + early == 1024)
+ nextBits = 11;
+ else if (nextCode + early == 2048)
+ nextBits = 12;
+ }
+ prevCode = code;
+
+ // reset buffer
+ seqIndex = 0;
- //----- initialize buffer
- bufPtr = bufEnd = buf;
+ return gTrue;
}
-void LZWStream::dumpFile(FILE *f) {
- int outCodeBits; // size of output code
- int outBits; // max output code
- int outBuf[8]; // output buffer
- int outData; // temporary output buffer
- int inCode, outCode; // input and output codes
- int nextCode; // next code index
- GBool eof; // set when EOF is reached
- GBool clear; // set if table needs to be cleared
- GBool first; // indicates first code word after clear
- int i, j;
-
- str->reset();
-
- // magic number
- fputc(0x1f, f);
- fputc(0x9d, f);
-
- // max code length, block mode flag
- fputc(0x8c, f);
-
- // init input side
- inCodeBits = 9;
- inputBuf = 0;
- inputBits = 0;
- eof = gFalse;
-
- // init output side
- outCodeBits = 9;
-
- // clear table
- first = gTrue;
+void LZWStream::clearTable() {
nextCode = 258;
-
- clear = gFalse;
- do {
- for (i = 0; i < 8; ++i) {
- // check for table overflow
- if (nextCode + early > 0x1001) {
- inCode = 256;
-
- // read input code
- } else {
- do {
- inCode = getCode();
- if (inCode == EOF) {
- eof = gTrue;
- inCode = 0;
- }
- } while (first && inCode == 256);
- }
-
- // compute output code
- if (inCode < 256) {
- outCode = inCode;
- } else if (inCode == 256) {
- outCode = 256;
- clear = gTrue;
- } else if (inCode == 257) {
- outCode = 0;
- eof = gTrue;
- } else {
- outCode = inCode - 1;
- }
- outBuf[i] = outCode;
-
- // next code index
- if (first)
- first = gFalse;
- else
- ++nextCode;
-
- // check input code size
- if (nextCode + early == 0x200)
- inCodeBits = 10;
- else if (nextCode + early == 0x400) {
- inCodeBits = 11;
- } else if (nextCode + early == 0x800) {
- inCodeBits = 12;
- }
-
- // check for eof/clear
- if (eof)
- break;
- if (clear) {
- i = 8;
- break;
- }
- }
-
- // write output block
- outData = 0;
- outBits = 0;
- j = 0;
- while (j < i || outBits > 0) {
- if (outBits < 8 && j < i) {
- outData = outData | (outBuf[j++] << outBits);
- outBits += outCodeBits;
- }
- fputc(outData & 0xff, f);
- outData >>= 8;
- outBits -= 8;
- }
-
- // check output code size
- if (nextCode - 1 == 512 ||
- nextCode - 1 == 1024 ||
- nextCode - 1 == 2048 ||
- nextCode - 1 == 4096) {
- outCodeBits = inCodeBits;
- }
-
- // clear table if necessary
- if (clear) {
- inCodeBits = 9;
- outCodeBits = 9;
- first = gTrue;
- nextCode = 258;
- clear = gFalse;
- }
- } while (!eof);
+ nextBits = 9;
+ seqIndex = seqLength = 0;
+ first = gTrue;
}
int LZWStream::getCode() {
int c;
int code;
- while (inputBits < inCodeBits) {
+ while (inputBits < nextBits) {
if ((c = str->getChar()) == EOF)
return EOF;
inputBuf = (inputBuf << 8) | (c & 0xff);
inputBits += 8;
}
- code = (inputBuf >> (inputBits - inCodeBits)) & ((1 << inCodeBits) - 1);
- inputBits -= inCodeBits;
+ code = (inputBuf >> (inputBits - nextBits)) & ((1 << nextBits) - 1);
+ inputBits -= nextBits;
return code;
}
-GBool LZWStream::fillBuf() {
- int n;
-
- if (!zPipe)
- return gFalse;
- if ((n = fread(buf, 1, 256, zPipe)) < 256) {
-#ifdef HAVE_POPEN
- pclose(zPipe);
-#else
- fclose(zPipe);
-#endif
- zPipe = NULL;
- unlink(zName->getCString());
- delete zName;
- }
- bufPtr = buf;
- bufEnd = buf + n;
- return n > 0;
-}
-
GString *LZWStream::getPSFilter(char *indent) {
GString *s;
@@ -1882,7 +1768,6 @@ GBool CCITTFaxStream::isBinary(GBool last) {
//------------------------------------------------------------------------
// IDCT constants (20.12 fixed point format)
-#ifndef FP_IDCT
#define dctCos1 4017 // cos(pi/16)
#define dctSin1 799 // sin(pi/16)
#define dctCos3 3406 // cos(3*pi/16)
@@ -1891,19 +1776,6 @@ GBool CCITTFaxStream::isBinary(GBool last) {
#define dctSin6 3784 // sin(6*pi/16)
#define dctSqrt2 5793 // sqrt(2)
#define dctSqrt1d2 2896 // sqrt(2) / 2
-#endif
-
-// IDCT constants
-#ifdef FP_IDCT
-#define dctCos1 0.98078528 // cos(pi/16)
-#define dctSin1 0.19509032 // sin(pi/16)
-#define dctCos3 0.83146961 // cos(3*pi/16)
-#define dctSin3 0.55557023 // sin(3*pi/16)
-#define dctCos6 0.38268343 // cos(6*pi/16)
-#define dctSin6 0.92387953 // sin(6*pi/16)
-#define dctSqrt2 1.41421356 // sqrt(2)
-#define dctSqrt1d2 0.70710678 // sqrt(2) / 2
-#endif
// color conversion parameters (16.16 fixed point format)
#define dctCrToR 91881 // 1.4020
@@ -1939,14 +1811,18 @@ DCTStream::DCTStream(Stream *strA):
FilterStream(strA) {
int i, j;
+ progressive = interleaved = gFalse;
width = height = 0;
mcuWidth = mcuHeight = 0;
numComps = 0;
comp = 0;
x = y = dy = 0;
- for (i = 0; i < 4; ++i)
- for (j = 0; j < 32; ++j)
+ for (i = 0; i < 4; ++i) {
+ for (j = 0; j < 32; ++j) {
rowBuf[i][j] = NULL;
+ }
+ frameBuf[i] = NULL;
+ }
if (!dctClipInit) {
for (i = -256; i < 0; ++i)
@@ -1963,53 +1839,172 @@ DCTStream::~DCTStream() {
int i, j;
delete str;
- for (i = 0; i < numComps; ++i)
- for (j = 0; j < mcuHeight; ++j)
- gfree(rowBuf[i][j]);
+ if (progressive || !interleaved) {
+ for (i = 0; i < numComps; ++i) {
+ gfree(frameBuf[i]);
+ }
+ } else {
+ for (i = 0; i < numComps; ++i) {
+ for (j = 0; j < mcuHeight; ++j) {
+ gfree(rowBuf[i][j]);
+ }
+ }
+ }
}
void DCTStream::reset() {
+ int minHSample, minVSample;
+ int i, j;
+
str->reset();
+
+ progressive = interleaved = gFalse;
+ width = height = 0;
+ numComps = 0;
+ numQuantTables = 0;
+ numDCHuffTables = 0;
+ numACHuffTables = 0;
+ colorXform = 0;
+ gotAdobeMarker = gFalse;
+ restartInterval = 0;
+
if (!readHeader()) {
y = height;
return;
}
- restartMarker = 0xd0;
- restart();
+
+ // compute MCU size
+ mcuWidth = minHSample = compInfo[0].hSample;
+ mcuHeight = minVSample = compInfo[0].vSample;
+ for (i = 1; i < numComps; ++i) {
+ if (compInfo[i].hSample < minHSample)
+ minHSample = compInfo[i].hSample;
+ if (compInfo[i].vSample < minVSample)
+ minVSample = compInfo[i].vSample;
+ if (compInfo[i].hSample > mcuWidth)
+ mcuWidth = compInfo[i].hSample;
+ if (compInfo[i].vSample > mcuHeight)
+ mcuHeight = compInfo[i].vSample;
+ }
+ for (i = 0; i < numComps; ++i) {
+ compInfo[i].hSample /= minHSample;
+ compInfo[i].vSample /= minVSample;
+ }
+ mcuWidth = (mcuWidth / minHSample) * 8;
+ mcuHeight = (mcuHeight / minVSample) * 8;
+
+ // figure out color transform
+ if (!gotAdobeMarker && numComps == 3) {
+ if (compInfo[0].id == 1 && compInfo[1].id == 2 && compInfo[2].id == 3) {
+ colorXform = 1;
+ }
+ }
+
+ if (progressive || !interleaved) {
+
+ // allocate a buffer for the whole image
+ bufWidth = ((width + mcuWidth - 1) / mcuWidth) * mcuWidth;
+ bufHeight = ((height + mcuHeight - 1) / mcuHeight) * mcuHeight;
+ for (i = 0; i < numComps; ++i) {
+ frameBuf[i] = (int *)gmalloc(bufWidth * bufHeight * sizeof(int));
+ memset(frameBuf[i], 0, bufWidth * bufHeight * sizeof(int));
+ }
+
+ // read the image data
+ do {
+ restartMarker = 0xd0;
+ restart();
+ readScan();
+ } while (readHeader());
+
+ // decode
+ decodeImage();
+
+ // initialize counters
+ comp = 0;
+ x = 0;
+ y = 0;
+
+ } else {
+
+ // allocate a buffer for one row of MCUs
+ bufWidth = ((width + mcuWidth - 1) / mcuWidth) * mcuWidth;
+ for (i = 0; i < numComps; ++i) {
+ for (j = 0; j < mcuHeight; ++j) {
+ rowBuf[i][j] = (Guchar *)gmalloc(bufWidth * sizeof(Guchar));
+ }
+ }
+
+ // initialize counters
+ comp = 0;
+ x = 0;
+ y = 0;
+ dy = mcuHeight;
+
+ restartMarker = 0xd0;
+ restart();
+ }
}
int DCTStream::getChar() {
int c;
- c = lookChar();
- if (c == EOF)
+ if (y >= height) {
return EOF;
- if (++comp == numComps) {
- comp = 0;
- if (++x == width) {
+ }
+ if (progressive || !interleaved) {
+ c = frameBuf[comp][y * bufWidth + x];
+ if (++comp == numComps) {
+ comp = 0;
+ if (++x == width) {
+ x = 0;
+ ++y;
+ }
+ }
+ } else {
+ if (dy >= mcuHeight) {
+ if (!readMCURow()) {
+ y = height;
+ return EOF;
+ }
+ comp = 0;
x = 0;
- ++y;
- ++dy;
+ dy = 0;
+ }
+ c = rowBuf[comp][dy][x];
+ if (++comp == numComps) {
+ comp = 0;
+ if (++x == width) {
+ x = 0;
+ ++y;
+ ++dy;
+ if (y == height) {
+ readTrailer();
+ }
+ }
}
}
- if (y == height)
- readTrailer();
return c;
}
int DCTStream::lookChar() {
- if (y >= height)
+ if (y >= height) {
return EOF;
- if (dy >= mcuHeight) {
- if (!readMCURow()) {
- y = height;
- return EOF;
+ }
+ if (progressive || !interleaved) {
+ return frameBuf[comp][y * bufWidth + x];
+ } else {
+ if (dy >= mcuHeight) {
+ if (!readMCURow()) {
+ y = height;
+ return EOF;
+ }
+ comp = 0;
+ x = 0;
+ dy = 0;
}
- comp = 0;
- x = 0;
- dy = 0;
+ return rowBuf[comp][dy][x];
}
- return rowBuf[comp][dy][x];
}
void DCTStream::restart() {
@@ -2017,12 +2012,16 @@ void DCTStream::restart() {
inputBits = 0;
restartCtr = restartInterval;
- for (i = 0; i < numComps; ++i)
+ for (i = 0; i < numComps; ++i) {
compInfo[i].prevDC = 0;
+ }
+ eobRun = 0;
}
+// Read one row of MCUs from a sequential JPEG stream.
GBool DCTStream::readMCURow() {
- Guchar data[64];
+ int data1[64];
+ Guchar data2[64];
Guchar *p1, *p2;
int pY, pCb, pCr, pR, pG, pB;
int h, v, horiz, vert, hSub, vSub;
@@ -2053,36 +2052,38 @@ GBool DCTStream::readMCURow() {
vSub = vert / 8;
for (y2 = 0; y2 < mcuHeight; y2 += vert) {
for (x2 = 0; x2 < mcuWidth; x2 += horiz) {
- if (!readDataUnit(&dcHuffTables[compInfo[cc].dcHuffTable],
- &acHuffTables[compInfo[cc].acHuffTable],
- quantTables[compInfo[cc].quantTable],
+ if (!readDataUnit(&dcHuffTables[scanInfo.dcHuffTable[cc]],
+ &acHuffTables[scanInfo.acHuffTable[cc]],
&compInfo[cc].prevDC,
- data))
+ data1)) {
return gFalse;
+ }
+ transformDataUnit(quantTables[compInfo[cc].quantTable],
+ data1, data2);
if (hSub == 1 && vSub == 1) {
for (y3 = 0, i = 0; y3 < 8; ++y3, i += 8) {
p1 = &rowBuf[cc][y2+y3][x1+x2];
- p1[0] = data[i];
- p1[1] = data[i+1];
- p1[2] = data[i+2];
- p1[3] = data[i+3];
- p1[4] = data[i+4];
- p1[5] = data[i+5];
- p1[6] = data[i+6];
- p1[7] = data[i+7];
+ p1[0] = data2[i];
+ p1[1] = data2[i+1];
+ p1[2] = data2[i+2];
+ p1[3] = data2[i+3];
+ p1[4] = data2[i+4];
+ p1[5] = data2[i+5];
+ p1[6] = data2[i+6];
+ p1[7] = data2[i+7];
}
} else if (hSub == 2 && vSub == 2) {
for (y3 = 0, i = 0; y3 < 16; y3 += 2, i += 8) {
p1 = &rowBuf[cc][y2+y3][x1+x2];
p2 = &rowBuf[cc][y2+y3+1][x1+x2];
- p1[0] = p1[1] = p2[0] = p2[1] = data[i];
- p1[2] = p1[3] = p2[2] = p2[3] = data[i+1];
- p1[4] = p1[5] = p2[4] = p2[5] = data[i+2];
- p1[6] = p1[7] = p2[6] = p2[7] = data[i+3];
- p1[8] = p1[9] = p2[8] = p2[9] = data[i+4];
- p1[10] = p1[11] = p2[10] = p2[11] = data[i+5];
- p1[12] = p1[13] = p2[12] = p2[13] = data[i+6];
- p1[14] = p1[15] = p2[14] = p2[15] = data[i+7];
+ p1[0] = p1[1] = p2[0] = p2[1] = data2[i];
+ p1[2] = p1[3] = p2[2] = p2[3] = data2[i+1];
+ p1[4] = p1[5] = p2[4] = p2[5] = data2[i+2];
+ p1[6] = p1[7] = p2[6] = p2[7] = data2[i+3];
+ p1[8] = p1[9] = p2[8] = p2[9] = data2[i+4];
+ p1[10] = p1[11] = p2[10] = p2[11] = data2[i+5];
+ p1[12] = p1[13] = p2[12] = p2[13] = data2[i+6];
+ p1[14] = p1[15] = p2[14] = p2[15] = data2[i+7];
}
} else {
i = 0;
@@ -2090,7 +2091,7 @@ GBool DCTStream::readMCURow() {
for (x3 = 0, x4 = 0; x3 < 8; ++x3, x4 += hSub) {
for (y5 = 0; y5 < vSub; ++y5)
for (x5 = 0; x5 < hSub; ++x5)
- rowBuf[cc][y2+y4+y5][x1+x2+x4+x5] = data[i];
+ rowBuf[cc][y2+y4+y5][x1+x2+x4+x5] = data2[i];
++i;
}
}
@@ -2138,71 +2139,466 @@ GBool DCTStream::readMCURow() {
return gTrue;
}
-// This IDCT algorithm is taken from:
-// Christoph Loeffler, Adriaan Ligtenberg, George S. Moschytz,
-// "Practical Fast 1-D DCT Algorithms with 11 Multiplications",
-// IEEE Intl. Conf. on Acoustics, Speech & Signal Processing, 1989,
-// 988-991.
-// The stage numbers mentioned in the comments refer to Figure 1 in this
-// paper.
-#ifndef FP_IDCT
+// Read one scan from a progressive or non-interleaved JPEG stream.
+void DCTStream::readScan() {
+ int data[64];
+ int x1, y1, dy1, x2, y2, y3, cc, i;
+ int h, v, horiz, vert, hSub, vSub;
+ int *p1;
+ int c;
+
+ if (scanInfo.numComps == 1) {
+ for (cc = 0; cc < numComps; ++cc) {
+ if (scanInfo.comp[cc]) {
+ break;
+ }
+ }
+ dy1 = mcuHeight / compInfo[cc].vSample;
+ } else {
+ dy1 = mcuHeight;
+ }
+
+ for (y1 = 0; y1 < bufHeight; y1 += dy1) {
+ for (x1 = 0; x1 < bufWidth; x1 += mcuWidth) {
+
+ // deal with restart marker
+ if (restartInterval > 0 && restartCtr == 0) {
+ c = readMarker();
+ if (c != restartMarker) {
+ error(getPos(), "Bad DCT data: incorrect restart marker");
+ return;
+ }
+ if (++restartMarker == 0xd8) {
+ restartMarker = 0xd0;
+ }
+ restart();
+ }
+
+ // read one MCU
+ for (cc = 0; cc < numComps; ++cc) {
+ if (!scanInfo.comp[cc]) {
+ continue;
+ }
+
+ h = compInfo[cc].hSample;
+ v = compInfo[cc].vSample;
+ horiz = mcuWidth / h;
+ vert = mcuHeight / v;
+ hSub = horiz / 8;
+ vSub = vert / 8;
+ for (y2 = 0; y2 < dy1; y2 += vert) {
+ for (x2 = 0; x2 < mcuWidth; x2 += horiz) {
+
+ // pull out the current values
+ p1 = &frameBuf[cc][(y1+y2) * bufWidth + (x1+x2)];
+ for (y3 = 0, i = 0; y3 < 8; ++y3, i += 8) {
+ data[i] = p1[0];
+ data[i+1] = p1[1];
+ data[i+2] = p1[2];
+ data[i+3] = p1[3];
+ data[i+4] = p1[4];
+ data[i+5] = p1[5];
+ data[i+6] = p1[6];
+ data[i+7] = p1[7];
+ p1 += bufWidth * vSub;
+ }
+
+ // read one data unit
+ if (progressive) {
+ if (!readProgressiveDataUnit(
+ &dcHuffTables[scanInfo.dcHuffTable[cc]],
+ &acHuffTables[scanInfo.acHuffTable[cc]],
+ &compInfo[cc].prevDC,
+ data)) {
+ return;
+ }
+ } else {
+ if (!readDataUnit(&dcHuffTables[scanInfo.dcHuffTable[cc]],
+ &acHuffTables[scanInfo.acHuffTable[cc]],
+ &compInfo[cc].prevDC,
+ data)) {
+ return;
+ }
+ }
+
+ // add the data unit into frameBuf
+ p1 = &frameBuf[cc][(y1+y2) * bufWidth + (x1+x2)];
+ for (y3 = 0, i = 0; y3 < 8; ++y3, i += 8) {
+ p1[0] = data[i];
+ p1[1] = data[i+1];
+ p1[2] = data[i+2];
+ p1[3] = data[i+3];
+ p1[4] = data[i+4];
+ p1[5] = data[i+5];
+ p1[6] = data[i+6];
+ p1[7] = data[i+7];
+ p1 += bufWidth * vSub;
+ }
+ }
+ }
+ }
+ --restartCtr;
+ }
+ }
+}
+
+// Read one data unit from a sequential JPEG stream.
GBool DCTStream::readDataUnit(DCTHuffTable *dcHuffTable,
DCTHuffTable *acHuffTable,
- Guchar quantTable[64], int *prevDC,
- Guchar data[64]) {
- int tmp1[64];
- int v0, v1, v2, v3, v4, v5, v6, v7, t;
+ int *prevDC, int data[64]) {
int run, size, amp;
int c;
int i, j;
- // Huffman decode and dequantize
- size = readHuffSym(dcHuffTable);
- if (size == 9999)
+ if ((size = readHuffSym(dcHuffTable)) == 9999) {
return gFalse;
+ }
if (size > 0) {
- amp = readAmp(size);
- if (amp == 9999)
+ if ((amp = readAmp(size)) == 9999) {
return gFalse;
+ }
} else {
amp = 0;
}
- tmp1[0] = (*prevDC += amp) * quantTable[0];
- for (i = 1; i < 64; ++i)
- tmp1[i] = 0;
+ data[0] = *prevDC += amp;
+ for (i = 1; i < 64; ++i) {
+ data[i] = 0;
+ }
i = 1;
while (i < 64) {
run = 0;
- while ((c = readHuffSym(acHuffTable)) == 0xf0 && run < 0x30)
+ while ((c = readHuffSym(acHuffTable)) == 0xf0 && run < 0x30) {
run += 0x10;
- if (c == 9999)
+ }
+ if (c == 9999) {
return gFalse;
+ }
if (c == 0x00) {
break;
} else {
run += (c >> 4) & 0x0f;
size = c & 0x0f;
amp = readAmp(size);
- if (amp == 9999)
+ if (amp == 9999) {
return gFalse;
+ }
i += run;
j = dctZigZag[i++];
- tmp1[j] = amp * quantTable[j];
+ data[j] = amp;
+ }
+ }
+ return gTrue;
+}
+
+// Read one data unit from a sequential JPEG stream.
+GBool DCTStream::readProgressiveDataUnit(DCTHuffTable *dcHuffTable,
+ DCTHuffTable *acHuffTable,
+ int *prevDC, int data[64]) {
+ int run, size, amp, bit, c;
+ int i, j, k;
+
+ // get the DC coefficient
+ i = scanInfo.firstCoeff;
+ if (i == 0) {
+ if (scanInfo.ah == 0) {
+ if ((size = readHuffSym(dcHuffTable)) == 9999) {
+ return gFalse;
+ }
+ if (size > 0) {
+ if ((amp = readAmp(size)) == 9999) {
+ return gFalse;
+ }
+ } else {
+ amp = 0;
+ }
+ data[0] += (*prevDC += amp) << scanInfo.al;
+ } else {
+ if ((bit = readBit()) == 9999) {
+ return gFalse;
+ }
+ data[0] += bit << scanInfo.al;
+ }
+ ++i;
+ }
+ if (scanInfo.lastCoeff == 0) {
+ return gTrue;
+ }
+
+ // check for an EOB run
+ if (eobRun > 0) {
+ while (i <= scanInfo.lastCoeff) {
+ j = dctZigZag[i++];
+ if (data[j] != 0) {
+ if ((bit = readBit()) == EOF) {
+ return gFalse;
+ }
+ if (bit) {
+ data[j] += 1 << scanInfo.al;
+ }
+ }
}
+ --eobRun;
+ return gTrue;
+ }
+
+ // read the AC coefficients
+ while (i <= scanInfo.lastCoeff) {
+ if ((c = readHuffSym(acHuffTable)) == 9999) {
+ return gFalse;
+ }
+
+ // ZRL
+ if (c == 0xf0) {
+ k = 0;
+ while (k < 16) {
+ j = dctZigZag[i++];
+ if (data[j] == 0) {
+ ++k;
+ } else {
+ if ((bit = readBit()) == EOF) {
+ return gFalse;
+ }
+ if (bit) {
+ data[j] += 1 << scanInfo.al;
+ }
+ }
+ }
+
+ // EOB run
+ } else if ((c & 0x0f) == 0x00) {
+ j = c >> 4;
+ eobRun = 0;
+ for (k = 0; k < j; ++k) {
+ if ((bit = readBit()) == EOF) {
+ return 9999;
+ }
+ eobRun = (eobRun << 1) | bit;
+ }
+ eobRun += 1 << j;
+ while (i <= scanInfo.lastCoeff) {
+ j = dctZigZag[i++];
+ if (data[j] != 0) {
+ if ((bit = readBit()) == EOF) {
+ return gFalse;
+ }
+ if (bit) {
+ data[j] += 1 << scanInfo.al;
+ }
+ }
+ }
+ --eobRun;
+ break;
+
+ // zero run and one AC coefficient
+ } else {
+ run = (c >> 4) & 0x0f;
+ size = c & 0x0f;
+ if ((amp = readAmp(size)) == 9999) {
+ return gFalse;
+ }
+ k = 0;
+ do {
+ j = dctZigZag[i++];
+ while (data[j] != 0) {
+ if ((bit = readBit()) == EOF) {
+ return gFalse;
+ }
+ if (bit) {
+ data[j] += 1 << scanInfo.al;
+ }
+ j = dctZigZag[i++];
+ }
+ ++k;
+ } while (k <= run);
+ data[j] = amp << scanInfo.al;
+ }
+ }
+
+ return gTrue;
+}
+
+// Decode a progressive JPEG image.
+void DCTStream::decodeImage() {
+ int dataIn[64];
+ Guchar dataOut[64];
+ Guchar *quantTable;
+ int pY, pCb, pCr, pR, pG, pB;
+ int x1, y1, x2, y2, x3, y3, x4, y4, x5, y5, cc, i;
+ int h, v, horiz, vert, hSub, vSub;
+ int *p0, *p1, *p2;
+
+ for (y1 = 0; y1 < bufHeight; y1 += mcuHeight) {
+ for (x1 = 0; x1 < bufWidth; x1 += mcuWidth) {
+ for (cc = 0; cc < numComps; ++cc) {
+ quantTable = quantTables[compInfo[cc].quantTable];
+ h = compInfo[cc].hSample;
+ v = compInfo[cc].vSample;
+ horiz = mcuWidth / h;
+ vert = mcuHeight / v;
+ hSub = horiz / 8;
+ vSub = vert / 8;
+ for (y2 = 0; y2 < mcuHeight; y2 += vert) {
+ for (x2 = 0; x2 < mcuWidth; x2 += horiz) {
+
+ // pull out the coded data unit
+ p1 = &frameBuf[cc][(y1+y2) * bufWidth + (x1+x2)];
+ for (y3 = 0, i = 0; y3 < 8; ++y3, i += 8) {
+ dataIn[i] = p1[0];
+ dataIn[i+1] = p1[1];
+ dataIn[i+2] = p1[2];
+ dataIn[i+3] = p1[3];
+ dataIn[i+4] = p1[4];
+ dataIn[i+5] = p1[5];
+ dataIn[i+6] = p1[6];
+ dataIn[i+7] = p1[7];
+ p1 += bufWidth * vSub;
+ }
+
+ // transform
+ transformDataUnit(quantTable, dataIn, dataOut);
+
+ // store back into frameBuf, doing replication for
+ // subsampled components
+ p1 = &frameBuf[cc][(y1+y2) * bufWidth + (x1+x2)];
+ if (hSub == 1 && vSub == 1) {
+ for (y3 = 0, i = 0; y3 < 8; ++y3, i += 8) {
+ p1[0] = dataOut[i] & 0xff;
+ p1[1] = dataOut[i+1] & 0xff;
+ p1[2] = dataOut[i+2] & 0xff;
+ p1[3] = dataOut[i+3] & 0xff;
+ p1[4] = dataOut[i+4] & 0xff;
+ p1[5] = dataOut[i+5] & 0xff;
+ p1[6] = dataOut[i+6] & 0xff;
+ p1[7] = dataOut[i+7] & 0xff;
+ p1 += bufWidth;
+ }
+ } else if (hSub == 2 && vSub == 2) {
+ p2 = p1 + bufWidth;
+ for (y3 = 0, i = 0; y3 < 16; y3 += 2, i += 8) {
+ p1[0] = p1[1] = p2[0] = p2[1] = dataOut[i] & 0xff;
+ p1[2] = p1[3] = p2[2] = p2[3] = dataOut[i+1] & 0xff;
+ p1[4] = p1[5] = p2[4] = p2[5] = dataOut[i+2] & 0xff;
+ p1[6] = p1[7] = p2[6] = p2[7] = dataOut[i+3] & 0xff;
+ p1[8] = p1[9] = p2[8] = p2[9] = dataOut[i+4] & 0xff;
+ p1[10] = p1[11] = p2[10] = p2[11] = dataOut[i+5] & 0xff;
+ p1[12] = p1[13] = p2[12] = p2[13] = dataOut[i+6] & 0xff;
+ p1[14] = p1[15] = p2[14] = p2[15] = dataOut[i+7] & 0xff;
+ p1 += bufWidth * 2;
+ p2 += bufWidth * 2;
+ }
+ } else {
+ i = 0;
+ for (y3 = 0, y4 = 0; y3 < 8; ++y3, y4 += vSub) {
+ for (x3 = 0, x4 = 0; x3 < 8; ++x3, x4 += hSub) {
+ p2 = p1 + x4;
+ for (y5 = 0; y5 < vSub; ++y5) {
+ for (x5 = 0; x5 < hSub; ++x5) {
+ p2[x5] = dataOut[i] & 0xff;
+ }
+ p2 += bufWidth;
+ }
+ ++i;
+ }
+ p1 += bufWidth * vSub;
+ }
+ }
+ }
+ }
+ }
+
+ // color space conversion
+ if (colorXform) {
+ // convert YCbCr to RGB
+ if (numComps == 3) {
+ for (y2 = 0; y2 < mcuHeight; ++y2) {
+ p0 = &frameBuf[0][(y1+y2) * bufWidth + x1];
+ p1 = &frameBuf[1][(y1+y2) * bufWidth + x1];
+ p2 = &frameBuf[2][(y1+y2) * bufWidth + x1];
+ for (x2 = 0; x2 < mcuWidth; ++x2) {
+ pY = *p0;
+ pCb = *p1 - 128;
+ pCr = *p2 - 128;
+ pR = ((pY << 16) + dctCrToR * pCr + 32768) >> 16;
+ *p0++ = dctClip[dctClipOffset + pR];
+ pG = ((pY << 16) + dctCbToG * pCb + dctCrToG * pCr +
+ 32768) >> 16;
+ *p1++ = dctClip[dctClipOffset + pG];
+ pB = ((pY << 16) + dctCbToB * pCb + 32768) >> 16;
+ *p2++ = dctClip[dctClipOffset + pB];
+ }
+ }
+ // convert YCbCrK to CMYK (K is passed through unchanged)
+ } else if (numComps == 4) {
+ for (y2 = 0; y2 < mcuHeight; ++y2) {
+ p0 = &frameBuf[0][(y1+y2) * bufWidth + x1];
+ p1 = &frameBuf[1][(y1+y2) * bufWidth + x1];
+ p2 = &frameBuf[2][(y1+y2) * bufWidth + x1];
+ for (x2 = 0; x2 < mcuWidth; ++x2) {
+ pY = *p0;
+ pCb = *p1 - 128;
+ pCr = *p2 - 128;
+ pR = ((pY << 16) + dctCrToR * pCr + 32768) >> 16;
+ *p0++ = 255 - dctClip[dctClipOffset + pR];
+ pG = ((pY << 16) + dctCbToG * pCb + dctCrToG * pCr +
+ 32768) >> 16;
+ *p1++ = 255 - dctClip[dctClipOffset + pG];
+ pB = ((pY << 16) + dctCbToB * pCb + 32768) >> 16;
+ *p2++ = 255 - dctClip[dctClipOffset + pB];
+ }
+ }
+ }
+ }
+ }
+ }
+}
+
+// Transform one data unit -- this performs the dequantization and
+// IDCT steps. This IDCT algorithm is taken from:
+// Christoph Loeffler, Adriaan Ligtenberg, George S. Moschytz,
+// "Practical Fast 1-D DCT Algorithms with 11 Multiplications",
+// IEEE Intl. Conf. on Acoustics, Speech & Signal Processing, 1989,
+// 988-991.
+// The stage numbers mentioned in the comments refer to Figure 1 in this
+// paper.
+void DCTStream::transformDataUnit(Guchar *quantTable,
+ int dataIn[64], Guchar dataOut[64]) {
+ int v0, v1, v2, v3, v4, v5, v6, v7, t;
+ int *p;
+ int i;
+
+ // dequant
+ for (i = 0; i < 64; ++i) {
+ dataIn[i] *= quantTable[i];
}
// inverse DCT on rows
for (i = 0; i < 64; i += 8) {
+ p = dataIn + i;
+
+ // check for all-zero AC coefficients
+ if (p[1] == 0 && p[2] == 0 && p[3] == 0 &&
+ p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] == 0) {
+ t = (dctSqrt2 * p[0] + 512) >> 10;
+ p[0] = t;
+ p[1] = t;
+ p[2] = t;
+ p[3] = t;
+ p[4] = t;
+ p[5] = t;
+ p[6] = t;
+ p[7] = t;
+ continue;
+ }
// stage 4
- v0 = (dctSqrt2 * tmp1[i+0] + 128) >> 8;
- v1 = (dctSqrt2 * tmp1[i+4] + 128) >> 8;
- v2 = tmp1[i+2];
- v3 = tmp1[i+6];
- v4 = (dctSqrt1d2 * (tmp1[i+1] - tmp1[i+7]) + 128) >> 8;
- v7 = (dctSqrt1d2 * (tmp1[i+1] + tmp1[i+7]) + 128) >> 8;
- v5 = tmp1[i+3] << 4;
- v6 = tmp1[i+5] << 4;
+ v0 = (dctSqrt2 * p[0] + 128) >> 8;
+ v1 = (dctSqrt2 * p[4] + 128) >> 8;
+ v2 = p[2];
+ v3 = p[6];
+ v4 = (dctSqrt1d2 * (p[1] - p[7]) + 128) >> 8;
+ v7 = (dctSqrt1d2 * (p[1] + p[7]) + 128) >> 8;
+ v5 = p[3] << 4;
+ v6 = p[5] << 4;
// stage 3
t = (v0 - v1+ 1) >> 1;
@@ -2233,28 +2629,44 @@ GBool DCTStream::readDataUnit(DCTHuffTable *dcHuffTable,
v6 = t;
// stage 1
- tmp1[i+0] = v0 + v7;
- tmp1[i+7] = v0 - v7;
- tmp1[i+1] = v1 + v6;
- tmp1[i+6] = v1 - v6;
- tmp1[i+2] = v2 + v5;
- tmp1[i+5] = v2 - v5;
- tmp1[i+3] = v3 + v4;
- tmp1[i+4] = v3 - v4;
+ p[0] = v0 + v7;
+ p[7] = v0 - v7;
+ p[1] = v1 + v6;
+ p[6] = v1 - v6;
+ p[2] = v2 + v5;
+ p[5] = v2 - v5;
+ p[3] = v3 + v4;
+ p[4] = v3 - v4;
}
// inverse DCT on columns
for (i = 0; i < 8; ++i) {
+ p = dataIn + i;
+
+ // check for all-zero AC coefficients
+ if (p[1*8] == 0 && p[2*8] == 0 && p[3*8] == 0 &&
+ p[4*8] == 0 && p[5*8] == 0 && p[6*8] == 0 && p[7*8] == 0) {
+ t = (dctSqrt2 * dataIn[i+0] + 8192) >> 14;
+ p[0*8] = t;
+ p[1*8] = t;
+ p[2*8] = t;
+ p[3*8] = t;
+ p[4*8] = t;
+ p[5*8] = t;
+ p[6*8] = t;
+ p[7*8] = t;
+ continue;
+ }
// stage 4
- v0 = (dctSqrt2 * tmp1[0*8+i] + 2048) >> 12;
- v1 = (dctSqrt2 * tmp1[4*8+i] + 2048) >> 12;
- v2 = tmp1[2*8+i];
- v3 = tmp1[6*8+i];
- v4 = (dctSqrt1d2 * (tmp1[1*8+i] - tmp1[7*8+i]) + 2048) >> 12;
- v7 = (dctSqrt1d2 * (tmp1[1*8+i] + tmp1[7*8+i]) + 2048) >> 12;
- v5 = tmp1[3*8+i];
- v6 = tmp1[5*8+i];
+ v0 = (dctSqrt2 * p[0*8] + 2048) >> 12;
+ v1 = (dctSqrt2 * p[4*8] + 2048) >> 12;
+ v2 = p[2*8];
+ v3 = p[6*8];
+ v4 = (dctSqrt1d2 * (p[1*8] - p[7*8]) + 2048) >> 12;
+ v7 = (dctSqrt1d2 * (p[1*8] + p[7*8]) + 2048) >> 12;
+ v5 = p[3*8];
+ v6 = p[5*8];
// stage 3
t = (v0 - v1 + 1) >> 1;
@@ -2285,181 +2697,21 @@ GBool DCTStream::readDataUnit(DCTHuffTable *dcHuffTable,
v6 = t;
// stage 1
- tmp1[0*8+i] = v0 + v7;
- tmp1[7*8+i] = v0 - v7;
- tmp1[1*8+i] = v1 + v6;
- tmp1[6*8+i] = v1 - v6;
- tmp1[2*8+i] = v2 + v5;
- tmp1[5*8+i] = v2 - v5;
- tmp1[3*8+i] = v3 + v4;
- tmp1[4*8+i] = v3 - v4;
+ p[0*8] = v0 + v7;
+ p[7*8] = v0 - v7;
+ p[1*8] = v1 + v6;
+ p[6*8] = v1 - v6;
+ p[2*8] = v2 + v5;
+ p[5*8] = v2 - v5;
+ p[3*8] = v3 + v4;
+ p[4*8] = v3 - v4;
}
// convert to 8-bit integers
- for (i = 0; i < 64; ++i)
- data[i] = dctClip[dctClipOffset + 128 + ((tmp1[i] + 8) >> 4)];
-
- return gTrue;
-}
-#endif
-
-#ifdef FP_IDCT
-GBool DCTStream::readDataUnit(DCTHuffTable *dcHuffTable,
- DCTHuffTable *acHuffTable,
- Guchar quantTable[64], int *prevDC,
- Guchar data[64]) {
- double tmp1[64];
- double v0, v1, v2, v3, v4, v5, v6, v7, t;
- int run, size, amp;
- int c;
- int i, j;
-
- // Huffman decode and dequantize
- size = readHuffSym(dcHuffTable);
- if (size == 9999)
- return gFalse;
- if (size > 0) {
- amp = readAmp(size);
- if (amp == 9999)
- return gFalse;
- } else {
- amp = 0;
- }
- tmp1[0] = (*prevDC += amp) * quantTable[0];
- for (i = 1; i < 64; ++i)
- tmp1[i] = 0;
- i = 1;
- while (i < 64) {
- run = 0;
- while ((c = readHuffSym(acHuffTable)) == 0xf0 && run < 0x30)
- run += 0x10;
- if (c == 9999)
- return gFalse;
- if (c == 0x00) {
- break;
- } else {
- run += (c >> 4) & 0x0f;
- size = c & 0x0f;
- amp = readAmp(size);
- if (amp == 9999)
- return gFalse;
- i += run;
- j = dctZigZag[i++];
- tmp1[j] = amp * quantTable[j];
- }
- }
-
- // inverse DCT on rows
- for (i = 0; i < 64; i += 8) {
-
- // stage 4
- v0 = dctSqrt2 * tmp1[i+0];
- v1 = dctSqrt2 * tmp1[i+4];
- v2 = tmp1[i+2];
- v3 = tmp1[i+6];
- v4 = dctSqrt1d2 * (tmp1[i+1] - tmp1[i+7]);
- v7 = dctSqrt1d2 * (tmp1[i+1] + tmp1[i+7]);
- v5 = tmp1[i+3];
- v6 = tmp1[i+5];
-
- // stage 3
- t = 0.5 * (v0 - v1);
- v0 = 0.5 * (v0 + v1);
- v1 = t;
- t = v2 * dctSin6 + v3 * dctCos6;
- v2 = v2 * dctCos6 - v3 * dctSin6;
- v3 = t;
- t = 0.5 * (v4 - v6);
- v4 = 0.5 * (v4 + v6);
- v6 = t;
- t = 0.5 * (v7 + v5);
- v5 = 0.5 * (v7 - v5);
- v7 = t;
-
- // stage 2
- t = 0.5 * (v0 - v3);
- v0 = 0.5 * (v0 + v3);
- v3 = t;
- t = 0.5 * (v1 - v2);
- v1 = 0.5 * (v1 + v2);
- v2 = t;
- t = v4 * dctSin3 + v7 * dctCos3;
- v4 = v4 * dctCos3 - v7 * dctSin3;
- v7 = t;
- t = v5 * dctSin1 + v6 * dctCos1;
- v5 = v5 * dctCos1 - v6 * dctSin1;
- v6 = t;
-
- // stage 1
- tmp1[i+0] = v0 + v7;
- tmp1[i+7] = v0 - v7;
- tmp1[i+1] = v1 + v6;
- tmp1[i+6] = v1 - v6;
- tmp1[i+2] = v2 + v5;
- tmp1[i+5] = v2 - v5;
- tmp1[i+3] = v3 + v4;
- tmp1[i+4] = v3 - v4;
- }
-
- // inverse DCT on columns
- for (i = 0; i < 8; ++i) {
-
- // stage 4
- v0 = dctSqrt2 * tmp1[0*8+i];
- v1 = dctSqrt2 * tmp1[4*8+i];
- v2 = tmp1[2*8+i];
- v3 = tmp1[6*8+i];
- v4 = dctSqrt1d2 * (tmp1[1*8+i] - tmp1[7*8+i]);
- v7 = dctSqrt1d2 * (tmp1[1*8+i] + tmp1[7*8+i]);
- v5 = tmp1[3*8+i];
- v6 = tmp1[5*8+i];
-
- // stage 3
- t = 0.5 * (v0 - v1);
- v0 = 0.5 * (v0 + v1);
- v1 = t;
- t = v2 * dctSin6 + v3 * dctCos6;
- v2 = v2 * dctCos6 - v3 * dctSin6;
- v3 = t;
- t = 0.5 * (v4 - v6);
- v4 = 0.5 * (v4 + v6);
- v6 = t;
- t = 0.5 * (v7 + v5);
- v5 = 0.5 * (v7 - v5);
- v7 = t;
-
- // stage 2
- t = 0.5 * (v0 - v3);
- v0 = 0.5 * (v0 + v3);
- v3 = t;
- t = 0.5 * (v1 - v2);
- v1 = 0.5 * (v1 + v2);
- v2 = t;
- t = v4 * dctSin3 + v7 * dctCos3;
- v4 = v4 * dctCos3 - v7 * dctSin3;
- v7 = t;
- t = v5 * dctSin1 + v6 * dctCos1;
- v5 = v5 * dctCos1 - v6 * dctSin1;
- v6 = t;
-
- // stage 1
- tmp1[0*8+i] = v0 + v7;
- tmp1[7*8+i] = v0 - v7;
- tmp1[1*8+i] = v1 + v6;
- tmp1[6*8+i] = v1 - v6;
- tmp1[2*8+i] = v2 + v5;
- tmp1[5*8+i] = v2 - v5;
- tmp1[3*8+i] = v3 + v4;
- tmp1[4*8+i] = v3 - v4;
+ for (i = 0; i < 64; ++i) {
+ dataOut[i] = dctClip[dctClipOffset + 128 + ((dataIn[i] + 8) >> 4)];
}
-
- // convert to 8-bit integers
- for (i = 0; i < 64; ++i)
- data[i] = dctClip[dctClipOffset + (int)(tmp1[i] + 128.5)];
-
- return gTrue;
}
-#endif
int DCTStream::readHuffSym(DCTHuffTable *table) {
Gushort code;
@@ -2527,20 +2779,9 @@ int DCTStream::readBit() {
GBool DCTStream::readHeader() {
GBool doScan;
- int minHSample, minVSample;
- int bufWidth;
int n;
int c = 0;
- int i, j;
-
- width = height = 0;
- numComps = 0;
- numQuantTables = 0;
- numDCHuffTables = 0;
- numACHuffTables = 0;
- colorXform = 0;
- gotAdobeMarker = gFalse;
- restartInterval = 0;
+ int i;
// read headers
doScan = gFalse;
@@ -2548,31 +2789,45 @@ GBool DCTStream::readHeader() {
c = readMarker();
switch (c) {
case 0xc0: // SOF0
- if (!readFrameInfo())
+ if (!readBaselineSOF()) {
return gFalse;
+ }
+ break;
+ case 0xc2: // SOF2
+ if (!readProgressiveSOF()) {
+ return gFalse;
+ }
break;
case 0xc4: // DHT
- if (!readHuffmanTables())
+ if (!readHuffmanTables()) {
return gFalse;
+ }
break;
case 0xd8: // SOI
break;
+ case 0xd9: // EOI
+ return gFalse;
+ break;
case 0xda: // SOS
- if (!readScanInfo())
+ if (!readScanInfo()) {
return gFalse;
+ }
doScan = gTrue;
break;
case 0xdb: // DQT
- if (!readQuantTables())
+ if (!readQuantTables()) {
return gFalse;
+ }
break;
case 0xdd: // DRI
- if (!readRestartInterval())
+ if (!readRestartInterval()) {
return gFalse;
+ }
break;
case 0xee: // APP14
- if (!readAdobeMarker())
+ if (!readAdobeMarker()) {
return gFalse;
+ }
break;
case EOF:
error(getPos(), "Bad DCT header");
@@ -2581,8 +2836,9 @@ GBool DCTStream::readHeader() {
// skip APPn / COM / etc.
if (c >= 0xe0) {
n = read16() - 2;
- for (i = 0; i < n; ++i)
+ for (i = 0; i < n; ++i) {
str->getChar();
+ }
} else {
error(getPos(), "Unknown DCT marker <%02x>", c);
return gFalse;
@@ -2591,107 +2847,98 @@ GBool DCTStream::readHeader() {
}
}
- // compute MCU size
- mcuWidth = minHSample = compInfo[0].hSample;
- mcuHeight = minVSample = compInfo[0].vSample;
- for (i = 1; i < numComps; ++i) {
- if (compInfo[i].hSample < minHSample)
- minHSample = compInfo[i].hSample;
- if (compInfo[i].vSample < minVSample)
- minVSample = compInfo[i].vSample;
- if (compInfo[i].hSample > mcuWidth)
- mcuWidth = compInfo[i].hSample;
- if (compInfo[i].vSample > mcuHeight)
- mcuHeight = compInfo[i].vSample;
- }
- for (i = 0; i < numComps; ++i) {
- compInfo[i].hSample /= minHSample;
- compInfo[i].vSample /= minVSample;
- }
- mcuWidth = (mcuWidth / minHSample) * 8;
- mcuHeight = (mcuHeight / minVSample) * 8;
+ return gTrue;
+}
- // allocate buffers
- bufWidth = ((width + mcuWidth - 1) / mcuWidth) * mcuWidth;
- for (i = 0; i < numComps; ++i)
- for (j = 0; j < mcuHeight; ++j)
- rowBuf[i][j] = (Guchar *)gmalloc(bufWidth * sizeof(Guchar));
+GBool DCTStream::readBaselineSOF() {
+ int length;
+ int prec;
+ int i;
+ int c;
- // figure out color transform
- if (!gotAdobeMarker && numComps == 3) {
- if (compInfo[0].id == 1 && compInfo[1].id == 2 && compInfo[2].id == 3) {
- colorXform = 1;
- }
+ length = read16();
+ prec = str->getChar();
+ height = read16();
+ width = read16();
+ numComps = str->getChar();
+ if (prec != 8) {
+ error(getPos(), "Bad DCT precision %d", prec);
+ return gFalse;
}
-
- // initialize counters
- comp = 0;
- x = 0;
- y = 0;
- dy = mcuHeight;
-
+ for (i = 0; i < numComps; ++i) {
+ compInfo[i].id = str->getChar();
+ c = str->getChar();
+ compInfo[i].hSample = (c >> 4) & 0x0f;
+ compInfo[i].vSample = c & 0x0f;
+ compInfo[i].quantTable = str->getChar();
+ }
+ progressive = gFalse;
return gTrue;
}
-GBool DCTStream::readFrameInfo() {
+GBool DCTStream::readProgressiveSOF() {
int length;
int prec;
int i;
int c;
- length = read16() - 2;
+ length = read16();
prec = str->getChar();
height = read16();
width = read16();
numComps = str->getChar();
- length -= 6;
if (prec != 8) {
error(getPos(), "Bad DCT precision %d", prec);
return gFalse;
}
for (i = 0; i < numComps; ++i) {
compInfo[i].id = str->getChar();
- compInfo[i].inScan = gFalse;
c = str->getChar();
compInfo[i].hSample = (c >> 4) & 0x0f;
compInfo[i].vSample = c & 0x0f;
compInfo[i].quantTable = str->getChar();
- compInfo[i].dcHuffTable = 0;
- compInfo[i].acHuffTable = 0;
}
+ progressive = gTrue;
return gTrue;
}
GBool DCTStream::readScanInfo() {
int length;
- int scanComps, id, c;
+ int id, c;
int i, j;
length = read16() - 2;
- scanComps = str->getChar();
+ scanInfo.numComps = str->getChar();
--length;
- if (length != 2 * scanComps + 3) {
+ if (length != 2 * scanInfo.numComps + 3) {
error(getPos(), "Bad DCT scan info block");
return gFalse;
}
- for (i = 0; i < scanComps; ++i) {
+ interleaved = scanInfo.numComps == numComps;
+ for (j = 0; j < numComps; ++j) {
+ scanInfo.comp[j] = gFalse;
+ }
+ for (i = 0; i < scanInfo.numComps; ++i) {
id = str->getChar();
for (j = 0; j < numComps; ++j) {
- if (id == compInfo[j].id)
+ if (id == compInfo[j].id) {
break;
+ }
}
if (j == numComps) {
error(getPos(), "Bad DCT component ID in scan info block");
return gFalse;
}
- compInfo[j].inScan = gTrue;
+ scanInfo.comp[j] = gTrue;
c = str->getChar();
- compInfo[j].dcHuffTable = (c >> 4) & 0x0f;
- compInfo[j].acHuffTable = c & 0x0f;
+ scanInfo.dcHuffTable[j] = (c >> 4) & 0x0f;
+ scanInfo.acHuffTable[j] = c & 0x0f;
}
- str->getChar();
- str->getChar();
- str->getChar();
+ scanInfo.firstCoeff = str->getChar();
+ scanInfo.lastCoeff = str->getChar();
+ c = str->getChar();
+ scanInfo.ah = (c >> 4) & 0x0f;
+ scanInfo.al = c & 0x0f;
return gTrue;
}
@@ -2779,17 +3026,25 @@ GBool DCTStream::readAdobeMarker() {
int c;
length = read16();
- if (length != 14)
+ if (length < 14) {
goto err;
+ }
for (i = 0; i < 12; ++i) {
- if ((c = str->getChar()) == EOF)
+ if ((c = str->getChar()) == EOF) {
goto err;
+ }
buf[i] = c;
}
- if (strncmp(buf, "Adobe", 5))
+ if (strncmp(buf, "Adobe", 5)) {
goto err;
+ }
colorXform = buf[11];
gotAdobeMarker = gTrue;
+ for (i = 14; i < length; ++i) {
+ if (str->getChar() == EOF) {
+ goto err;
+ }
+ }
return gTrue;
err:
@@ -2927,9 +3182,13 @@ FlateStream::FlateStream(Stream *strA, int predictor, int columns,
} else {
pred = NULL;
}
+ litCodeTab.codes = NULL;
+ distCodeTab.codes = NULL;
}
FlateStream::~FlateStream() {
+ gfree(litCodeTab.codes);
+ gfree(distCodeTab.codes);
if (pred) {
delete pred;
}
@@ -3096,6 +3355,12 @@ GBool FlateStream::startBlock() {
int c;
int check;
+ // free the code tables from the previous block
+ gfree(litCodeTab.codes);
+ litCodeTab.codes = NULL;
+ gfree(distCodeTab.codes);
+ distCodeTab.codes = NULL;
+
// read block header
blockHdr = getCodeWord(3);
if (blockHdr & 1)
@@ -3130,8 +3395,9 @@ GBool FlateStream::startBlock() {
// compressed block with dynamic codes
} else if (blockHdr == 2) {
compressedBlock = gTrue;
- if (!readDynamicCodes())
+ if (!readDynamicCodes()) {
goto err;
+ }
// unknown block type
} else {
@@ -3150,186 +3416,182 @@ err:
void FlateStream::loadFixedCodes() {
int i;
- // set up code arrays
- litCodeTab.codes = allCodes;
- distCodeTab.codes = allCodes + flateMaxLitCodes;
-
- // initialize literal code table
- for (i = 0; i <= 143; ++i)
- litCodeTab.codes[i].len = 8;
- for (i = 144; i <= 255; ++i)
- litCodeTab.codes[i].len = 9;
- for (i = 256; i <= 279; ++i)
- litCodeTab.codes[i].len = 7;
- for (i = 280; i <= 287; ++i)
- litCodeTab.codes[i].len = 8;
- compHuffmanCodes(&litCodeTab, flateMaxLitCodes);
-
- // initialize distance code table
- for (i = 0; i <= 5; ++i) {
- distCodeTab.start[i] = 0;
+ // build the literal code table
+ for (i = 0; i <= 143; ++i) {
+ codeLengths[i] = 8;
+ }
+ for (i = 144; i <= 255; ++i) {
+ codeLengths[i] = 9;
}
- for (i = 6; i <= flateMaxHuffman+1; ++i) {
- distCodeTab.start[i] = flateMaxDistCodes;
+ for (i = 256; i <= 279; ++i) {
+ codeLengths[i] = 7;
}
+ for (i = 280; i <= 287; ++i) {
+ codeLengths[i] = 8;
+ }
+ compHuffmanCodes(codeLengths, flateMaxLitCodes, &litCodeTab);
+
+ // build the distance code table
for (i = 0; i < flateMaxDistCodes; ++i) {
- distCodeTab.codes[i].len = 5;
- distCodeTab.codes[i].code = i;
- distCodeTab.codes[i].val = i;
+ codeLengths[i] = 5;
}
+ compHuffmanCodes(codeLengths, flateMaxDistCodes, &distCodeTab);
}
GBool FlateStream::readDynamicCodes() {
int numCodeLenCodes;
int numLitCodes;
int numDistCodes;
- FlateCode codeLenCodes[flateMaxCodeLenCodes];
+ int codeLenCodeLengths[flateMaxCodeLenCodes];
FlateHuffmanTab codeLenCodeTab;
int len, repeat, code;
int i;
// read lengths
- if ((numLitCodes = getCodeWord(5)) == EOF)
+ if ((numLitCodes = getCodeWord(5)) == EOF) {
goto err;
+ }
numLitCodes += 257;
- if ((numDistCodes = getCodeWord(5)) == EOF)
+ if ((numDistCodes = getCodeWord(5)) == EOF) {
goto err;
+ }
numDistCodes += 1;
- if ((numCodeLenCodes = getCodeWord(4)) == EOF)
+ if ((numCodeLenCodes = getCodeWord(4)) == EOF) {
goto err;
+ }
numCodeLenCodes += 4;
if (numLitCodes > flateMaxLitCodes ||
numDistCodes > flateMaxDistCodes ||
- numCodeLenCodes > flateMaxCodeLenCodes)
+ numCodeLenCodes > flateMaxCodeLenCodes) {
goto err;
+ }
- // read code length code table
- codeLenCodeTab.codes = codeLenCodes;
- for (i = 0; i < flateMaxCodeLenCodes; ++i)
- codeLenCodes[i].len = 0;
+ // build the code length code table
+ for (i = 0; i < flateMaxCodeLenCodes; ++i) {
+ codeLenCodeLengths[i] = 0;
+ }
for (i = 0; i < numCodeLenCodes; ++i) {
- if ((codeLenCodes[codeLenCodeMap[i]].len = getCodeWord(3)) == -1)
+ if ((codeLenCodeLengths[codeLenCodeMap[i]] = getCodeWord(3)) == -1) {
goto err;
+ }
}
- compHuffmanCodes(&codeLenCodeTab, flateMaxCodeLenCodes);
-
- // set up code arrays
- litCodeTab.codes = allCodes;
- distCodeTab.codes = allCodes + numLitCodes;
+ compHuffmanCodes(codeLenCodeLengths, flateMaxCodeLenCodes, &codeLenCodeTab);
- // read literal and distance code tables
+ // build the literal and distance code tables
len = 0;
repeat = 0;
i = 0;
while (i < numLitCodes + numDistCodes) {
- if ((code = getHuffmanCodeWord(&codeLenCodeTab)) == EOF)
+ if ((code = getHuffmanCodeWord(&codeLenCodeTab)) == EOF) {
goto err;
+ }
if (code == 16) {
- if ((repeat = getCodeWord(2)) == EOF)
+ if ((repeat = getCodeWord(2)) == EOF) {
goto err;
- for (repeat += 3; repeat > 0; --repeat)
- allCodes[i++].len = len;
+ }
+ for (repeat += 3; repeat > 0; --repeat) {
+ codeLengths[i++] = len;
+ }
} else if (code == 17) {
- if ((repeat = getCodeWord(3)) == EOF)
+ if ((repeat = getCodeWord(3)) == EOF) {
goto err;
+ }
len = 0;
- for (repeat += 3; repeat > 0; --repeat)
- allCodes[i++].len = 0;
+ for (repeat += 3; repeat > 0; --repeat) {
+ codeLengths[i++] = 0;
+ }
} else if (code == 18) {
- if ((repeat = getCodeWord(7)) == EOF)
+ if ((repeat = getCodeWord(7)) == EOF) {
goto err;
+ }
len = 0;
- for (repeat += 11; repeat > 0; --repeat)
- allCodes[i++].len = 0;
+ for (repeat += 11; repeat > 0; --repeat) {
+ codeLengths[i++] = 0;
+ }
} else {
- allCodes[i++].len = len = code;
+ codeLengths[i++] = len = code;
}
}
- compHuffmanCodes(&litCodeTab, numLitCodes);
- compHuffmanCodes(&distCodeTab, numDistCodes);
+ compHuffmanCodes(codeLengths, numLitCodes, &litCodeTab);
+ compHuffmanCodes(codeLengths + numLitCodes, numDistCodes, &distCodeTab);
+ gfree(codeLenCodeTab.codes);
return gTrue;
err:
error(getPos(), "Bad dynamic code table in flate stream");
+ gfree(codeLenCodeTab.codes);
return gFalse;
}
-// On entry, the <tab->codes> array contains the lengths of each code,
-// stored in code value order. This function computes the code words.
-// The result is sorted in order of (1) code length and (2) code word.
-// The length values are no longer valid. The <tab->start> array is
-// filled with the indexes of the first code of each length.
-void FlateStream::compHuffmanCodes(FlateHuffmanTab *tab, int n) {
- int numLengths[flateMaxHuffman+1];
- int nextCode[flateMaxHuffman+1];
- int nextIndex[flateMaxHuffman+2];
- int code;
- int i, j;
+// Convert an array <lengths> of <n> lengths, in value order, into a
+// Huffman code lookup table.
+void FlateStream::compHuffmanCodes(int *lengths, int n, FlateHuffmanTab *tab) {
+ int tabSize, len, code, code2, skip, val, i, t;
- // count number of codes for each code length
- for (i = 0; i <= flateMaxHuffman; ++i)
- numLengths[i] = 0;
- for (i = 0; i < n; ++i)
- ++numLengths[tab->codes[i].len];
+ // find max code length
+ tab->maxLen = 0;
+ for (val = 0; val < n; ++val) {
+ if (lengths[val] > tab->maxLen) {
+ tab->maxLen = lengths[val];
+ }
+ }
- // compute first index for each length
- tab->start[0] = nextIndex[0] = 0;
- for (i = 1; i <= flateMaxHuffman + 1; ++i)
- tab->start[i] = nextIndex[i] = tab->start[i-1] + numLengths[i-1];
+ // allocate the table
+ tabSize = 1 << tab->maxLen;
+ tab->codes = (FlateCode *)gmalloc(tabSize * sizeof(FlateCode));
- // compute first code for each length
- code = 0;
- numLengths[0] = 0;
- for (i = 1; i <= flateMaxHuffman; ++i) {
- code = (code + numLengths[i-1]) << 1;
- nextCode[i] = code;
+ // clear the table
+ for (i = 0; i < tabSize; ++i) {
+ tab->codes[i].len = 0;
+ tab->codes[i].val = 0;
}
- // compute the codes -- this permutes the codes array from value
- // order to length/code order
- for (i = 0; i < n; ++i) {
- j = nextIndex[tab->codes[i].len]++;
- if (tab->codes[i].len == 0)
- tab->codes[j].code = 0;
- else
- tab->codes[j].code = nextCode[tab->codes[i].len]++;
- tab->codes[j].val = i;
+ // build the table
+ for (len = 1, code = 0, skip = 2;
+ len <= tab->maxLen;
+ ++len, code <<= 1, skip <<= 1) {
+ for (val = 0; val < n; ++val) {
+ if (lengths[val] == len) {
+
+ // bit-reverse the code
+ code2 = 0;
+ t = code;
+ for (i = 0; i < len; ++i) {
+ code2 = (code2 << 1) | (t & 1);
+ t >>= 1;
+ }
+
+ // fill in the table entries
+ for (i = code2; i < tabSize; i += skip) {
+ tab->codes[i].len = (Gushort)len;
+ tab->codes[i].val = (Gushort)val;
+ }
+
+ ++code;
+ }
+ }
}
}
int FlateStream::getHuffmanCodeWord(FlateHuffmanTab *tab) {
- int len;
- int code;
+ FlateCode *code;
int c;
- int i, j;
-
- code = 0;
- for (len = 1; len <= flateMaxHuffman; ++len) {
-
- // add a bit to the code
- if (codeSize == 0) {
- if ((c = str->getChar()) == EOF)
- return EOF;
- codeBuf = c & 0xff;
- codeSize = 8;
- }
- code = (code << 1) | (codeBuf & 1);
- codeBuf >>= 1;
- --codeSize;
- // look for code
- i = tab->start[len];
- j = tab->start[len + 1];
- if (i < j && code >= tab->codes[i].code && code <= tab->codes[j-1].code) {
- i += code - tab->codes[i].code;
- return tab->codes[i].val;
+ while (codeSize < tab->maxLen) {
+ if ((c = str->getChar()) == EOF) {
+ break;
}
+ codeBuf |= (c & 0xff) << codeSize;
+ codeSize += 8;
}
-
- // not found
- error(getPos(), "Bad code (%04x) in flate stream", code);
- return EOF;
+ code = &tab->codes[codeBuf & ((1 << tab->maxLen) - 1)];
+ if (codeSize == 0 || codeSize < code->len || code->len == 0) {
+ return EOF;
+ }
+ codeBuf >>= code->len;
+ codeSize -= code->len;
+ return (int)code->val;
}
int FlateStream::getCodeWord(int bits) {
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