libpgf  6.14.12
PGF - Progressive Graphics File
CEncoder::CMacroBlock Class Reference

A macro block is an encoding unit of fixed size (uncoded) More...

Public Member Functions

 CMacroBlock (CEncoder *encoder)
 
void Init (int lastLevelIndex)
 
void BitplaneEncode ()
 

Public Attributes

DataT m_value [BufferSize]
 input buffer of values with index m_valuePos More...
 
UINT32 m_codeBuffer [CodeBufferLen]
 output buffer for encoded bitstream More...
 
ROIBlockHeader m_header
 block header More...
 
UINT32 m_valuePos
 current buffer position More...
 
UINT32 m_maxAbsValue
 maximum absolute coefficient in each buffer More...
 
UINT32 m_codePos
 current position in encoded bitstream More...
 
int m_lastLevelIndex
 index of last encoded level: [0, nLevels); used because a level-end can occur before a buffer is full More...
 

Private Member Functions

UINT32 RLESigns (UINT32 codePos, UINT32 *signBits, UINT32 signLen)
 
UINT32 DecomposeBitplane (UINT32 bufferSize, UINT32 planeMask, UINT32 codePos, UINT32 *sigBits, UINT32 *refBits, UINT32 *signBits, UINT32 &signLen, UINT32 &codeLen)
 
UINT8 NumberOfBitplanes ()
 
bool GetBitAtPos (UINT32 pos, UINT32 planeMask) const
 

Private Attributes

CEncoderm_encoder
 
bool m_sigFlagVector [BufferSize+1]
 

Detailed Description

A macro block is an encoding unit of fixed size (uncoded)

PGF encoder macro block class.

Author
C. Stamm, I. Bauersachs

Definition at line 51 of file Encoder.h.

Constructor & Destructor Documentation

◆ CMacroBlock()

CEncoder::CMacroBlock::CMacroBlock ( CEncoder encoder)
inline

Constructor: Initializes new macro block.

Parameters
encoderPointer to outer class.

Definition at line 56 of file Encoder.h.

57  : 4351 )
58  : m_value()
59  , m_codeBuffer()
60  , m_header(0)
61  , m_encoder(encoder)
62  , m_sigFlagVector()
63  {
64  ASSERT(m_encoder);
65  Init(-1);
66  }
bool m_sigFlagVector[BufferSize+1]
Definition: Encoder.h:99
CEncoder * m_encoder
Definition: Encoder.h:98
UINT32 m_codeBuffer[CodeBufferLen]
output buffer for encoded bitstream
Definition: Encoder.h:85
DataT m_value[BufferSize]
input buffer of values with index m_valuePos
Definition: Encoder.h:84
ROIBlockHeader m_header
block header
Definition: Encoder.h:86
void Init(int lastLevelIndex)
Definition: Encoder.h:71

Member Function Documentation

◆ BitplaneEncode()

void CEncoder::CMacroBlock::BitplaneEncode ( )

Encodes this macro block into internal code buffer. Several macro blocks can be encoded in parallel. Call CEncoder::WriteMacroBlock after this method.

Definition at line 480 of file Encoder.cpp.

480  {
481  UINT8 nPlanes;
482  UINT32 sigLen, codeLen = 0, wordPos, refLen, signLen;
483  UINT32 sigBits[BufferLen] = { 0 };
484  UINT32 refBits[BufferLen] = { 0 };
485  UINT32 signBits[BufferLen] = { 0 };
486  UINT32 planeMask;
487  UINT32 bufferSize = m_header.rbh.bufferSize; ASSERT(bufferSize <= BufferSize);
488  bool useRL;
489 
490 #ifdef TRACE
491  //printf("which thread: %d\n", omp_get_thread_num());
492 #endif
493 
494  // clear significance vector
495  for (UINT32 k=0; k < bufferSize; k++) {
496  m_sigFlagVector[k] = false;
497  }
498  m_sigFlagVector[bufferSize] = true; // sentinel
499 
500  // clear output buffer
501  for (UINT32 k=0; k < bufferSize; k++) {
502  m_codeBuffer[k] = 0;
503  }
504  m_codePos = 0;
505 
506  // compute number of bit planes and split buffer into separate bit planes
507  nPlanes = NumberOfBitplanes();
508 
509  // write number of bit planes to m_codeBuffer
510  // <nPlanes>
513 
514  // loop through all bit planes
515  if (nPlanes == 0) nPlanes = MaxBitPlanes + 1;
516  planeMask = 1 << (nPlanes - 1);
517 
518  for (int plane = nPlanes - 1; plane >= 0; plane--) {
519  // clear significant bitset
520  for (UINT32 k=0; k < BufferLen; k++) {
521  sigBits[k] = 0;
522  }
523 
524  // split bitplane in significant bitset and refinement bitset
525  sigLen = DecomposeBitplane(bufferSize, planeMask, m_codePos + RLblockSizeLen + 1, sigBits, refBits, signBits, signLen, codeLen);
526 
527  if (sigLen > 0 && codeLen <= MaxCodeLen && codeLen < AlignWordPos(sigLen) + AlignWordPos(signLen) + 2*RLblockSizeLen) {
528  // set RL code bit
529  // <1><codeLen>
531 
532  // write length codeLen to m_codeBuffer
534  m_codePos += RLblockSizeLen + codeLen;
535  } else {
536  #ifdef TRACE
537  //printf("new\n");
538  //for (UINT32 i=0; i < bufferSize; i++) {
539  // printf("%s", (GetBit(sigBits, i)) ? "1" : "_");
540  // if (i%120 == 119) printf("\n");
541  //}
542  //printf("\n");
543  #endif // TRACE
544 
545  // run-length coding wasn't efficient enough
546  // we don't use RL coding for sigBits
547  // <0><sigLen>
549 
550  // write length sigLen to m_codeBuffer
551  ASSERT(sigLen <= MaxCodeLen);
554 
555  if (m_encoder->m_favorSpeed || signLen == 0) {
556  useRL = false;
557  } else {
558  // overwrite m_codeBuffer
559  useRL = true;
560  // run-length encode m_sign and append them to the m_codeBuffer
561  codeLen = RLESigns(m_codePos + RLblockSizeLen + 1, signBits, signLen);
562  }
563 
564  if (useRL && codeLen <= MaxCodeLen && codeLen < signLen) {
565  // RL encoding of m_sign was efficient
566  // <1><codeLen><codedSignBits>_
567  // write RL code bit
569 
570  // write codeLen to m_codeBuffer
572 
573  // compute position of sigBits
574  wordPos = NumberOfWords(m_codePos + RLblockSizeLen + codeLen);
575  ASSERT(0 <= wordPos && wordPos < CodeBufferLen);
576  } else {
577  // RL encoding of signBits wasn't efficient
578  // <0><signLen>_<signBits>_
579  // clear RL code bit
581 
582  // write signLen to m_codeBuffer
583  ASSERT(signLen <= MaxCodeLen);
585 
586  // write signBits to m_codeBuffer
588  ASSERT(0 <= wordPos && wordPos < CodeBufferLen);
589  codeLen = NumberOfWords(signLen);
590 
591  for (UINT32 k=0; k < codeLen; k++) {
592  m_codeBuffer[wordPos++] = signBits[k];
593  }
594  }
595 
596  // write sigBits
597  // <sigBits>_
598  ASSERT(0 <= wordPos && wordPos < CodeBufferLen);
599  refLen = NumberOfWords(sigLen);
600 
601  for (UINT32 k=0; k < refLen; k++) {
602  m_codeBuffer[wordPos++] = sigBits[k];
603  }
604  m_codePos = wordPos << WordWidthLog;
605  }
606 
607  // append refinement bitset (aligned to word boundary)
608  // _<refBits>
609  wordPos = NumberOfWords(m_codePos);
610  ASSERT(0 <= wordPos && wordPos < CodeBufferLen);
611  refLen = NumberOfWords(bufferSize - sigLen);
612 
613  for (UINT32 k=0; k < refLen; k++) {
614  m_codeBuffer[wordPos++] = refBits[k];
615  }
616  m_codePos = wordPos << WordWidthLog;
617  planeMask >>= 1;
618  }
619  ASSERT(0 <= m_codePos && m_codePos <= CodeBufferBitLen);
620 }
struct ROIBlockHeader::RBH rbh
ROI block header.
UINT16 bufferSize
number of uncoded UINT32 values in a block
Definition: PGFtypes.h:167
UINT8 NumberOfBitplanes()
Definition: Encoder.cpp:748
UINT32 AlignWordPos(UINT32 pos)
Definition: BitStream.h:260
#define BufferSize
must be a multiple of WordWidth
Definition: PGFtypes.h:77
UINT32 m_codePos
current position in encoded bitstream
Definition: Encoder.h:89
UINT32 RLESigns(UINT32 codePos, UINT32 *signBits, UINT32 signLen)
Definition: Encoder.cpp:772
#define RLblockSizeLen
block size length (< 16): ld(BufferSize) < RLblockSizeLen <= 2*ld(BufferSize)
Definition: PGFtypes.h:78
bool m_sigFlagVector[BufferSize+1]
Definition: Encoder.h:99
#define WordWidthLog
ld of WordWidth
Definition: PGFplatform.h:74
#define BufferLen
number of words per buffer
Definition: Decoder.h:39
void ClearBit(UINT32 *stream, UINT32 pos)
Definition: BitStream.h:56
#define MaxBitPlanesLog
number of bits to code the maximum number of bit planes (in 32 or 16 bit mode)
Definition: PGFtypes.h:86
UINT32 DecomposeBitplane(UINT32 bufferSize, UINT32 planeMask, UINT32 codePos, UINT32 *sigBits, UINT32 *refBits, UINT32 *signBits, UINT32 &signLen, UINT32 &codeLen)
Definition: Encoder.cpp:632
CEncoder * m_encoder
Definition: Encoder.h:98
UINT32 m_codeBuffer[CodeBufferLen]
output buffer for encoded bitstream
Definition: Encoder.h:85
void SetBit(UINT32 *stream, UINT32 pos)
Definition: BitStream.h:48
UINT32 NumberOfWords(UINT32 pos)
Definition: BitStream.h:269
#define MaxBitPlanes
maximum number of bit planes of m_value: 32 minus sign bit
Definition: PGFtypes.h:82
bool m_favorSpeed
favor speed over size
Definition: Encoder.h:222
void SetValueBlock(UINT32 *stream, UINT32 pos, UINT32 val, UINT32 k)
Definition: BitStream.h:102
ROIBlockHeader m_header
block header
Definition: Encoder.h:86
#define CodeBufferLen
number of words in code buffer (CodeBufferLen > BufferLen)
Definition: Decoder.h:40
#define MaxCodeLen
max length of RL encoded block
Definition: Encoder.cpp:59
#define CodeBufferBitLen
max number of bits in m_codeBuffer
Definition: Encoder.cpp:58

◆ DecomposeBitplane()

UINT32 CEncoder::CMacroBlock::DecomposeBitplane ( UINT32  bufferSize,
UINT32  planeMask,
UINT32  codePos,
UINT32 *  sigBits,
UINT32 *  refBits,
UINT32 *  signBits,
UINT32 &  signLen,
UINT32 &  codeLen 
)
private

Definition at line 632 of file Encoder.cpp.

632  {
633  ASSERT(sigBits);
634  ASSERT(refBits);
635  ASSERT(signBits);
636  ASSERT(codePos < CodeBufferBitLen);
637 
638  UINT32 sigPos = 0;
639  UINT32 valuePos = 0, valueEnd;
640  UINT32 refPos = 0;
641 
642  // set output value
643  signLen = 0;
644 
645  // prepare RLE of Sigs and Signs
646  const UINT32 outStartPos = codePos;
647  UINT32 k = 3;
648  UINT32 runlen = 1 << k; // = 2^k
649  UINT32 count = 0;
650 
651  while (valuePos < bufferSize) {
652  // search next 1 in m_sigFlagVector using searching with sentinel
653  valueEnd = valuePos;
654  while(!m_sigFlagVector[valueEnd]) { valueEnd++; }
655 
656  // search 1's in m_value[plane][valuePos..valueEnd)
657  // these 1's are significant bits
658  while (valuePos < valueEnd) {
659  if (GetBitAtPos(valuePos, planeMask)) {
660  // RLE encoding
661  // encode run of count 0's followed by a 1
662  // with codeword: 1<count>(signBits[signPos])
663  SetBit(m_codeBuffer, codePos++);
664  if (k > 0) {
665  SetValueBlock(m_codeBuffer, codePos, count, k);
666  codePos += k;
667 
668  // adapt k (half the zero run-length)
669  k--;
670  runlen >>= 1;
671  }
672 
673  // copy and write sign bit
674  if (m_value[valuePos] < 0) {
675  SetBit(signBits, signLen++);
676  SetBit(m_codeBuffer, codePos++);
677  } else {
678  ClearBit(signBits, signLen++);
679  ClearBit(m_codeBuffer, codePos++);
680  }
681 
682  // write a 1 to sigBits
683  SetBit(sigBits, sigPos++);
684 
685  // update m_sigFlagVector
686  m_sigFlagVector[valuePos] = true;
687 
688  // prepare for next run
689  count = 0;
690  } else {
691  // RLE encoding
692  count++;
693  if (count == runlen) {
694  // encode run of 2^k zeros by a single 0
695  ClearBit(m_codeBuffer, codePos++);
696  // adapt k (double the zero run-length)
697  if (k < WordWidth) {
698  k++;
699  runlen <<= 1;
700  }
701 
702  // prepare for next run
703  count = 0;
704  }
705 
706  // write 0 to sigBits
707  sigPos++;
708  }
709  valuePos++;
710  }
711  // refinement bit
712  if (valuePos < bufferSize) {
713  // write one refinement bit
714  if (GetBitAtPos(valuePos++, planeMask)) {
715  SetBit(refBits, refPos);
716  } else {
717  ClearBit(refBits, refPos);
718  }
719  refPos++;
720  }
721  }
722  // RLE encoding of the rest of the plane
723  // encode run of count 0's followed by a 1
724  // with codeword: 1<count>(signBits[signPos])
725  SetBit(m_codeBuffer, codePos++);
726  if (k > 0) {
727  SetValueBlock(m_codeBuffer, codePos, count, k);
728  codePos += k;
729  }
730  // write dmmy sign bit
731  SetBit(m_codeBuffer, codePos++);
732 
733  // write word filler zeros
734 
735  ASSERT(sigPos <= bufferSize);
736  ASSERT(refPos <= bufferSize);
737  ASSERT(signLen <= bufferSize);
738  ASSERT(valuePos == bufferSize);
739  ASSERT(codePos >= outStartPos && codePos < CodeBufferBitLen);
740  codeLen = codePos - outStartPos;
741 
742  return sigPos;
743 }
bool m_sigFlagVector[BufferSize+1]
Definition: Encoder.h:99
void ClearBit(UINT32 *stream, UINT32 pos)
Definition: BitStream.h:56
bool GetBitAtPos(UINT32 pos, UINT32 planeMask) const
Definition: Encoder.h:96
UINT32 m_codeBuffer[CodeBufferLen]
output buffer for encoded bitstream
Definition: Encoder.h:85
void SetBit(UINT32 *stream, UINT32 pos)
Definition: BitStream.h:48
void SetValueBlock(UINT32 *stream, UINT32 pos, UINT32 val, UINT32 k)
Definition: BitStream.h:102
DataT m_value[BufferSize]
input buffer of values with index m_valuePos
Definition: Encoder.h:84
#define WordWidth
WordBytes*8.
Definition: PGFplatform.h:73
#define CodeBufferBitLen
max number of bits in m_codeBuffer
Definition: Encoder.cpp:58

◆ GetBitAtPos()

bool CEncoder::CMacroBlock::GetBitAtPos ( UINT32  pos,
UINT32  planeMask 
) const
inlineprivate

Definition at line 96 of file Encoder.h.

96 { return (abs(m_value[pos]) & planeMask) > 0; }
DataT m_value[BufferSize]
input buffer of values with index m_valuePos
Definition: Encoder.h:84

◆ Init()

void CEncoder::CMacroBlock::Init ( int  lastLevelIndex)
inline

Reinitialzes this macro block (allows reusage).

Parameters
lastLevelIndexLevel length directory index of last encoded level: [0, nLevels)

Definition at line 71 of file Encoder.h.

71  { // initialize for reusage
72  m_valuePos = 0;
73  m_maxAbsValue = 0;
74  m_codePos = 0;
75  m_lastLevelIndex = lastLevelIndex;
76  }
UINT32 m_valuePos
current buffer position
Definition: Encoder.h:87
int m_lastLevelIndex
index of last encoded level: [0, nLevels); used because a level-end can occur before a buffer is full...
Definition: Encoder.h:90
UINT32 m_maxAbsValue
maximum absolute coefficient in each buffer
Definition: Encoder.h:88
UINT32 m_codePos
current position in encoded bitstream
Definition: Encoder.h:89

◆ NumberOfBitplanes()

UINT8 CEncoder::CMacroBlock::NumberOfBitplanes ( )
private

Definition at line 748 of file Encoder.cpp.

748  {
749  UINT8 cnt = 0;
750 
751  // determine number of bitplanes for max value
752  if (m_maxAbsValue > 0) {
753  while (m_maxAbsValue > 0) {
754  m_maxAbsValue >>= 1; cnt++;
755  }
756  if (cnt == MaxBitPlanes + 1) cnt = 0;
757  // end cs
758  ASSERT(cnt <= MaxBitPlanes);
759  ASSERT((cnt >> MaxBitPlanesLog) == 0);
760  return cnt;
761  } else {
762  return 1;
763  }
764 }
UINT32 m_maxAbsValue
maximum absolute coefficient in each buffer
Definition: Encoder.h:88
#define MaxBitPlanesLog
number of bits to code the maximum number of bit planes (in 32 or 16 bit mode)
Definition: PGFtypes.h:86
#define MaxBitPlanes
maximum number of bit planes of m_value: 32 minus sign bit
Definition: PGFtypes.h:82

◆ RLESigns()

UINT32 CEncoder::CMacroBlock::RLESigns ( UINT32  codePos,
UINT32 *  signBits,
UINT32  signLen 
)
private

Definition at line 772 of file Encoder.cpp.

772  {
773  ASSERT(signBits);
774  ASSERT(0 <= codePos && codePos < CodeBufferBitLen);
775  ASSERT(0 < signLen && signLen <= BufferSize);
776 
777  const UINT32 outStartPos = codePos;
778  UINT32 k = 0;
779  UINT32 runlen = 1 << k; // = 2^k
780  UINT32 count = 0;
781  UINT32 signPos = 0;
782 
783  while (signPos < signLen) {
784  // search next 0 in signBits starting at position signPos
785  count = SeekBit1Range(signBits, signPos, __min(runlen, signLen - signPos));
786  // count 1's found
787  if (count == runlen) {
788  // encode run of 2^k ones by a single 1
789  signPos += count;
790  SetBit(m_codeBuffer, codePos++);
791  // adapt k (double the 1's run-length)
792  if (k < WordWidth) {
793  k++;
794  runlen <<= 1;
795  }
796  } else {
797  // encode run of count 1's followed by a 0
798  // with codeword: 0(count)
799  signPos += count + 1;
800  ClearBit(m_codeBuffer, codePos++);
801  if (k > 0) {
802  SetValueBlock(m_codeBuffer, codePos, count, k);
803  codePos += k;
804  }
805  // adapt k (half the 1's run-length)
806  if (k > 0) {
807  k--;
808  runlen >>= 1;
809  }
810  }
811  }
812  ASSERT(signPos == signLen || signPos == signLen + 1);
813  ASSERT(codePos >= outStartPos && codePos < CodeBufferBitLen);
814  return codePos - outStartPos;
815 }
#define BufferSize
must be a multiple of WordWidth
Definition: PGFtypes.h:77
void ClearBit(UINT32 *stream, UINT32 pos)
Definition: BitStream.h:56
UINT32 SeekBit1Range(UINT32 *stream, UINT32 pos, UINT32 len)
Definition: BitStream.h:235
#define __min(x, y)
Definition: PGFplatform.h:91
UINT32 m_codeBuffer[CodeBufferLen]
output buffer for encoded bitstream
Definition: Encoder.h:85
void SetBit(UINT32 *stream, UINT32 pos)
Definition: BitStream.h:48
void SetValueBlock(UINT32 *stream, UINT32 pos, UINT32 val, UINT32 k)
Definition: BitStream.h:102
#define WordWidth
WordBytes*8.
Definition: PGFplatform.h:73
#define CodeBufferBitLen
max number of bits in m_codeBuffer
Definition: Encoder.cpp:58

Member Data Documentation

◆ m_codeBuffer

UINT32 CEncoder::CMacroBlock::m_codeBuffer[CodeBufferLen]

output buffer for encoded bitstream

Definition at line 85 of file Encoder.h.

◆ m_codePos

UINT32 CEncoder::CMacroBlock::m_codePos

current position in encoded bitstream

Definition at line 89 of file Encoder.h.

◆ m_encoder

CEncoder* CEncoder::CMacroBlock::m_encoder
private

Definition at line 98 of file Encoder.h.

◆ m_header

ROIBlockHeader CEncoder::CMacroBlock::m_header

block header

Definition at line 86 of file Encoder.h.

◆ m_lastLevelIndex

int CEncoder::CMacroBlock::m_lastLevelIndex

index of last encoded level: [0, nLevels); used because a level-end can occur before a buffer is full

Definition at line 90 of file Encoder.h.

◆ m_maxAbsValue

UINT32 CEncoder::CMacroBlock::m_maxAbsValue

maximum absolute coefficient in each buffer

Definition at line 88 of file Encoder.h.

◆ m_sigFlagVector

bool CEncoder::CMacroBlock::m_sigFlagVector[BufferSize+1]
private

Definition at line 99 of file Encoder.h.

◆ m_value

DataT CEncoder::CMacroBlock::m_value[BufferSize]

input buffer of values with index m_valuePos

Definition at line 84 of file Encoder.h.

◆ m_valuePos

UINT32 CEncoder::CMacroBlock::m_valuePos

current buffer position

Definition at line 87 of file Encoder.h.


The documentation for this class was generated from the following files: