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/*
*
* Copyright (C) 2007-2024, OFFIS e.V.
* All rights reserved. See COPYRIGHT file for details.
*
* This software and supporting documentation were developed by
*
* OFFIS e.V.
* R&D Division Health
* Escherweg 2
* D-26121 Oldenburg, Germany
*
*
* Module: dcmjpls
*
* Author: Martin Willkomm, Marco Eichelberg, Uli Schlachter
*
* Purpose: codec classes for JPEG-LS encoders.
*
*/
#include "dcmtk/config/osconfig.h"
#include "dcmtk/dcmjpls/djcodece.h"
// ofstd includes
#include "dcmtk/ofstd/oflist.h"
#include "dcmtk/ofstd/ofstd.h"
#include "dcmtk/ofstd/ofstream.h"
#include "dcmtk/ofstd/offile.h" /* for class OFFile */
#include "dcmtk/ofstd/ofbmanip.h"
// dcmdata includes
#include "dcmtk/dcmdata/dcdatset.h" /* for class DcmDataset */
#include "dcmtk/dcmdata/dcdeftag.h" /* for tag constants */
#include "dcmtk/dcmdata/dcovlay.h" /* for class DcmOverlayData */
#include "dcmtk/dcmdata/dcpixseq.h" /* for class DcmPixelSequence */
#include "dcmtk/dcmdata/dcpxitem.h" /* for class DcmPixelItem */
#include "dcmtk/dcmdata/dcuid.h" /* for dcmGenerateUniqueIdentifer()*/
#include "dcmtk/dcmdata/dcvrcs.h" /* for class DcmCodeString */
#include "dcmtk/dcmdata/dcvrds.h" /* for class DcmDecimalString */
#include "dcmtk/dcmdata/dcvrlt.h" /* for class DcmLongText */
#include "dcmtk/dcmdata/dcvrst.h" /* for class DcmShortText */
#include "dcmtk/dcmdata/dcvrus.h" /* for class DcmUnsignedShort */
#include "dcmtk/dcmdata/dcswap.h" /* for swapIfNecessary */
// dcmjpls includes
#include "dcmtk/dcmjpls/djcparam.h" /* for class DJLSCodecParameter */
#include "dcmtk/dcmjpls/djrparam.h" /* for class D2RepresentationParameter */
#include "djerror.h" /* for private class DJLSError */
// dcmimgle includes
#include "dcmtk/dcmimgle/dcmimage.h" /* for class DicomImage */
// JPEG-LS library (CharLS) includes
#include "intrface.h"
BEGIN_EXTERN_C
#ifdef HAVE_FCNTL_H
#include <fcntl.h> /* for O_RDONLY */
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h> /* required for sys/stat.h */
#endif
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h> /* for stat, fstat */
#endif
END_EXTERN_C
E_TransferSyntax DJLSLosslessEncoder::supportedTransferSyntax() const
{
return EXS_JPEGLSLossless;
}
E_TransferSyntax DJLSNearLosslessEncoder::supportedTransferSyntax() const
{
return EXS_JPEGLSLossy;
}
// --------------------------------------------------------------------------
DJLSEncoderBase::DJLSEncoderBase()
: DcmCodec()
{
}
DJLSEncoderBase::~DJLSEncoderBase()
{
}
OFBool DJLSEncoderBase::canChangeCoding(
const E_TransferSyntax oldRepType,
const E_TransferSyntax newRepType) const
{
// this codec only handles conversion from uncompressed to JPEG-LS.
DcmXfer oldRep(oldRepType);
return (oldRep.usesNativeFormat() && (newRepType == supportedTransferSyntax()));
}
OFCondition DJLSEncoderBase::decode(
const DcmRepresentationParameter * /* fromRepParam */,
DcmPixelSequence * /* pixSeq */,
DcmPolymorphOBOW& /* uncompressedPixelData */,
const DcmCodecParameter * /* cp */,
const DcmStack& /* objStack */,
OFBool& /* removeOldRep */ ) const
{
// we are an encoder only
return EC_IllegalCall;
}
OFCondition DJLSEncoderBase::decodeFrame(
const DcmRepresentationParameter * /* fromParam */ ,
DcmPixelSequence * /* fromPixSeq */ ,
const DcmCodecParameter * /* cp */ ,
DcmItem * /* dataset */ ,
Uint32 /* frameNo */ ,
Uint32& /* startFragment */ ,
void * /* buffer */ ,
Uint32 /* bufSize */ ,
OFString& /* decompressedColorModel */ ) const
{
// we are an encoder only
return EC_IllegalCall;
}
OFCondition DJLSEncoderBase::encode(
const E_TransferSyntax /* fromRepType */,
const DcmRepresentationParameter * /* fromRepParam */,
DcmPixelSequence * /* fromPixSeq */,
const DcmRepresentationParameter * /* toRepParam */,
DcmPixelSequence * & /* toPixSeq */,
const DcmCodecParameter * /* cp */,
DcmStack& /* objStack */,
OFBool& /* removeOldRep */ ) const
{
// we don't support re-coding for now.
return EC_IllegalCall;
}
OFCondition DJLSEncoderBase::encode(
const Uint16 * pixelData,
const Uint32 length,
const DcmRepresentationParameter * toRepParam,
DcmPixelSequence * & pixSeq,
const DcmCodecParameter *cp,
DcmStack& objStack,
OFBool& removeOldRep) const
{
OFCondition result = EC_Normal;
DJLSRepresentationParameter defRep;
// this codec may modify the DICOM header such that the previous pixel
// representation is not valid anymore. Indicate this to the caller
// to trigger removal.
removeOldRep = OFTrue;
// retrieve pointer to dataset from parameter stack
DcmStack localStack(objStack);
(void)localStack.pop(); // pop pixel data element from stack
DcmObject *dobject = localStack.pop(); // this is the item in which the pixel data is located
if ((!dobject)||((dobject->ident()!= EVR_dataset) && (dobject->ident()!= EVR_item))) return EC_InvalidTag;
DcmItem *dataset = OFstatic_cast(DcmItem *, dobject);
// assume we can cast the codec and representation parameters to what we need
const DJLSCodecParameter *djcp = OFreinterpret_cast(const DJLSCodecParameter *, cp);
const DJLSRepresentationParameter *djrp = OFreinterpret_cast(const DJLSRepresentationParameter *, toRepParam);
double compressionRatio = 0.0;
if (!djrp)
djrp = &defRep;
if (supportedTransferSyntax() == EXS_JPEGLSLossless || djrp->useLosslessProcess())
{
if (djcp->cookedEncodingPreferred())
result = losslessCookedEncode(pixelData, length, dataset, djrp, pixSeq, djcp, compressionRatio, 0);
else result = losslessRawEncode(pixelData, length, dataset, djrp, pixSeq, djcp, compressionRatio);
}
else
{
// near-lossless mode always uses the "cooked" encoder since this one is guaranteed not to "mix"
// overlays and pixel data in one cell subjected to lossy compression.
result = losslessCookedEncode(pixelData, length, dataset, djrp, pixSeq, djcp, compressionRatio, djrp->getnearlosslessDeviation());
}
// the following operations do not affect the Image Pixel Module
// but other modules such as SOP Common. We only perform these
// changes if we're on the main level of the dataset,
// which should always identify itself as dataset, not as item.
if (result.good() && dataset->ident() == EVR_dataset)
{
if (result.good())
{
if (supportedTransferSyntax() == EXS_JPEGLSLossless || djrp->useLosslessProcess())
{
// lossless process - create new UID if mode is EUC_always or if we're converting to Secondary Capture
if (djcp->getConvertToSC() || (djcp->getUIDCreation() == EJLSUC_always))
result = DcmCodec::newInstance(dataset, "DCM", "121320", "Uncompressed predecessor");
}
else
{
// lossy process - create new UID unless mode is EUC_never and we're not converting to Secondary Capture
if (djcp->getConvertToSC() || (djcp->getUIDCreation() != EJLSUC_never))
result = DcmCodec::newInstance(dataset, "DCM", "121320", "Uncompressed predecessor");
// update image type
if (result.good()) result = DcmCodec::updateImageType(dataset);
// update derivation description
if (result.good()) result = updateDerivationDescription(dataset, djrp, compressionRatio);
// update lossy compression ratio
if (result.good()) result = updateLossyCompressionRatio(dataset, compressionRatio);
}
}
// convert to Secondary Capture if requested by user.
// This method creates a new SOP class UID, so it should be executed
// after the call to newInstance() which creates a Source Image Sequence.
if (result.good() && djcp->getConvertToSC()) result = DcmCodec::convertToSecondaryCapture(dataset);
}
return result;
}
OFCondition DJLSEncoderBase::determineDecompressedColorModel(
const DcmRepresentationParameter * /* fromParam */,
DcmPixelSequence * /* fromPixSeq */,
const DcmCodecParameter * /* cp */,
DcmItem * /* dataset */,
OFString & /* decompressedColorModel */) const
{
return EC_IllegalCall;
}
OFCondition DJLSEncoderBase::adjustOverlays(
DcmItem *dataset,
DicomImage& image) const
{
if (dataset == NULL) return EC_IllegalCall;
unsigned int overlayCount = image.getOverlayCount();
if (overlayCount > 0)
{
Uint16 group = 0;
DcmStack stack;
unsigned long bytesAllocated = 0;
Uint8 *buffer = NULL;
unsigned int width = 0;
unsigned int height = 0;
unsigned long frames = 0;
DcmElement *elem = NULL;
OFCondition result = EC_Normal;
// adjust overlays (prior to grayscale compression)
for (unsigned int i=0; i < overlayCount; i++)
{
// check if current overlay is embedded in pixel data
group = OFstatic_cast(Uint16, image.getOverlayGroupNumber(i));
stack.clear();
if ((dataset->search(DcmTagKey(group, 0x3000), stack, ESM_fromHere, OFFalse)).bad())
{
// separate Overlay Data not found. Assume overlay is embedded.
bytesAllocated = image.create6xxx3000OverlayData(buffer, i, width, height, frames);
if (bytesAllocated > 0)
{
elem = new DcmOverlayData(DcmTagKey(group, 0x3000)); // DCM_OverlayData
if (elem)
{
result = elem->putUint8Array(buffer, bytesAllocated);
delete[] buffer;
if (result.good())
{
dataset->insert(elem, OFTrue /*replaceOld*/);
// DCM_OverlayBitsAllocated
result = dataset->putAndInsertUint16(DcmTagKey(group, 0x0100), 1);
// DCM_OverlayBitPosition
if (result.good()) result = dataset->putAndInsertUint16(DcmTagKey(group, 0x0102), 0);
}
else
{
delete elem;
return result;
}
}
else
{
delete[] buffer;
return EC_MemoryExhausted;
}
}
else return EC_IllegalCall;
}
}
}
return EC_Normal;
}
OFCondition DJLSEncoderBase::updateLossyCompressionRatio(
DcmItem *dataset,
double ratio) const
{
if (dataset == NULL) return EC_IllegalCall;
// set Lossy Image Compression to "01" (see DICOM part 3, C.7.6.1.1.5)
OFCondition result = dataset->putAndInsertString(DCM_LossyImageCompression, "01");
if (result.bad()) return result;
// set Lossy Image Compression Ratio
OFString s;
const char *oldRatio = NULL;
if ((dataset->findAndGetString(DCM_LossyImageCompressionRatio, oldRatio)).good() && oldRatio)
{
s = oldRatio;
s += "\\";
}
// append lossy compression ratio
char buf[64];
OFStandard::ftoa(buf, sizeof(buf), ratio, OFStandard::ftoa_uppercase, 0, 5);
s += buf;
result = dataset->putAndInsertString(DCM_LossyImageCompressionRatio, s.c_str());
if (result.bad()) return result;
// count VM of lossy image compression ratio
size_t i;
size_t s_vm = 0;
size_t s_sz = s.size();
for (i = 0; i < s_sz; ++i)
if (s[i] == '\\') ++s_vm;
// set Lossy Image Compression Method
const char *oldMethod = NULL;
OFString m;
if ((dataset->findAndGetString(DCM_LossyImageCompressionMethod, oldMethod)).good() && oldMethod)
{
m = oldMethod;
m += "\\";
}
// count VM of lossy image compression method
size_t m_vm = 0;
size_t m_sz = m.size();
for (i = 0; i < m_sz; ++i)
if (m[i] == '\\') ++m_vm;
// make sure that VM of Compression Method is not smaller than VM of Compression Ratio
while (m_vm++ < s_vm) m += "\\";
m += "ISO_14495_1";
return dataset->putAndInsertString(DCM_LossyImageCompressionMethod, m.c_str());
}
OFCondition DJLSEncoderBase::updateDerivationDescription(
DcmItem *dataset,
const DJLSRepresentationParameter *djrp,
double ratio) const
{
OFString derivationDescription;
char buf[64];
derivationDescription = "near lossless JPEG-LS compression, factor ";
OFStandard::ftoa(buf, sizeof(buf), ratio, OFStandard::ftoa_uppercase, 0, 5);
derivationDescription += buf;
OFStandard::snprintf(buf, sizeof(buf), " (NEAR=%lu)", OFstatic_cast(unsigned long, djrp->getnearlosslessDeviation()));
derivationDescription += buf;
// append old Derivation Description, if any
const char *oldDerivation = NULL;
if ((dataset->findAndGetString(DCM_DerivationDescription, oldDerivation)).good() && oldDerivation)
{
derivationDescription += " [";
derivationDescription += oldDerivation;
derivationDescription += "]";
if (derivationDescription.length() > 1024)
{
// ST is limited to 1024 characters, cut off tail
derivationDescription.erase(1020);
derivationDescription += "...]";
}
}
OFCondition result = dataset->putAndInsertString(DCM_DerivationDescription, derivationDescription.c_str());
if (result.good()) result = DcmCodec::insertCodeSequence(dataset, DCM_DerivationCodeSequence, "DCM", "113040", "Lossy Compression");
return result;
}
OFCondition DJLSEncoderBase::losslessRawEncode(
const Uint16 *pixelData,
const Uint32 length,
DcmItem *dataset,
const DJLSRepresentationParameter *djrp,
DcmPixelSequence * & pixSeq,
const DJLSCodecParameter *djcp,
double& compressionRatio) const
{
compressionRatio = 0.0; // initialize if something goes wrong
// determine image properties
Uint16 bitsAllocated = 0;
Uint16 bitsStored = 0;
Uint16 bytesAllocated = 0;
Uint16 samplesPerPixel = 0;
Uint16 planarConfiguration = 0;
Uint16 columns = 0;
Uint16 rows = 0;
Sint32 numberOfFrames = 1;
OFBool byteSwapped = OFFalse; // true if we have byte-swapped the original pixel data
OFString photometricInterpretation;
OFCondition result = dataset->findAndGetUint16(DCM_BitsAllocated, bitsAllocated);
if (result.good()) result = dataset->findAndGetUint16(DCM_BitsStored, bitsStored);
if (result.good()) result = dataset->findAndGetUint16(DCM_SamplesPerPixel, samplesPerPixel);
if (result.good()) result = dataset->findAndGetUint16(DCM_Columns, columns);
if (result.good()) result = dataset->findAndGetUint16(DCM_Rows, rows);
if (result.good()) result = dataset->findAndGetOFString(DCM_PhotometricInterpretation, photometricInterpretation);
if (result.good())
{
result = dataset->findAndGetSint32(DCM_NumberOfFrames, numberOfFrames);
if (result.bad() || numberOfFrames < 1) numberOfFrames = 1;
result = EC_Normal;
}
if (result.good() && (samplesPerPixel > 1))
{
result = dataset->findAndGetUint16(DCM_PlanarConfiguration, planarConfiguration);
}
if (result.good())
{
// check if bitsAllocated is 8 or 16 - we don't handle anything else
if (bitsAllocated == 8)
{
bytesAllocated = 1;
}
else if (bitsAllocated == 16)
{
bytesAllocated = 2;
}
else
{
if (photometricInterpretation == "MONOCHROME1" ||
photometricInterpretation == "MONOCHROME2" ||
photometricInterpretation == "RGB" ||
photometricInterpretation == "YBR_FULL")
{
// A bitsAllocated value that we don't handle, but a color model that indicates
// that the cooked encoder could handle this case. Fall back to cooked encoder.
return losslessCookedEncode(pixelData, length, dataset, djrp, pixSeq, djcp, compressionRatio, 0);
}
// an image that is not supported by either the raw or the cooked encoder.
result = EC_JLSUnsupportedImageType;
}
}
if (result.good())
{
// make sure that all the descriptive attributes have sensible values
if ((columns < 1)||(rows < 1)||(samplesPerPixel < 1)) result = EC_JLSUnsupportedImageType;
}
if (result.good())
{
// we do not support JPEG-LS compression of YBR_FULL_422 images
if (photometricInterpretation == "YBR_FULL_422")
result = EC_JLSUnsupportedImageType;
}
if (result.good())
{
// make sure that we have at least as many bytes of pixel data as we expect
if (bytesAllocated * samplesPerPixel * columns * rows *
OFstatic_cast(unsigned long,numberOfFrames) > length)
result = EC_JLSUncompressedBufferTooSmall;
}
DcmPixelSequence *pixelSequence = NULL;
DcmPixelItem *offsetTable = NULL;
// create initial pixel sequence
if (result.good())
{
pixelSequence = new DcmPixelSequence(DCM_PixelSequenceTag);
if (pixelSequence == NULL) result = EC_MemoryExhausted;
else
{
// create empty offset table
offsetTable = new DcmPixelItem(DCM_PixelItemTag);
if (offsetTable == NULL) result = EC_MemoryExhausted;
else pixelSequence->insert(offsetTable);
}
}
DcmOffsetList offsetList;
unsigned long compressedSize = 0;
unsigned long compressedFrameSize = 0;
double uncompressedSize = 0.0;
// render and compress each frame
if (result.good())
{
// byte swap pixel data to little endian if bits allocate is 8
if ((gLocalByteOrder == EBO_BigEndian) && (bitsAllocated == 8))
{
swapIfNecessary(EBO_LittleEndian, gLocalByteOrder, OFstatic_cast(void *, OFconst_cast(Uint16 *, pixelData)), length, sizeof(Uint16));
byteSwapped = OFTrue;
}
unsigned long frameCount = OFstatic_cast(unsigned long, numberOfFrames);
unsigned long frameSize = columns * rows * samplesPerPixel * bytesAllocated;
const Uint8 *framePointer = OFreinterpret_cast(const Uint8 *, pixelData);
// compute original image size in bytes, ignoring any padding bits.
uncompressedSize = columns * rows * samplesPerPixel * bitsStored * frameCount / 8.0;
for (unsigned long i=0; (i<frameCount) && (result.good()); ++i)
{
// compress frame
DCMJPLS_DEBUG("JPEG-LS encoder processes frame " << (i+1) << " of " << frameCount);
result = compressRawFrame(framePointer, bitsAllocated, columns, rows,
samplesPerPixel, planarConfiguration, photometricInterpretation,
pixelSequence, offsetList, compressedFrameSize, djcp);
compressedSize += compressedFrameSize;
framePointer += frameSize;
}
}
// store pixel sequence if everything went well.
if (result.good()) pixSeq = pixelSequence;
else
{
delete pixelSequence;
pixSeq = NULL;
}
// create offset table
if ((result.good()) && (djcp->getCreateOffsetTable()))
{
result = offsetTable->createOffsetTable(offsetList);
}
// adjust planar configuration
if (result.good())
{
if (photometricInterpretation == "RGB" || photometricInterpretation == "YBR_FULL")
{
// CP 1843 requires a planar configuration value of 0 for these color models
result = dataset->putAndInsertUint16(DCM_PlanarConfiguration, 0);
}
else if (samplesPerPixel == 1)
{
delete dataset->remove(DCM_PlanarConfiguration);
}
}
if (compressedSize > 0) compressionRatio = uncompressedSize / compressedSize;
// byte swap pixel data back to local endian if necessary
if (byteSwapped)
{
swapIfNecessary(gLocalByteOrder, EBO_LittleEndian, OFstatic_cast(void *, OFconst_cast(Uint16 *, pixelData)), length, sizeof(Uint16));
}
return result;
}
// static helper functions for DJLSEncoderBase::setCustomParameters().
static long setcp_clamp(long i, long j, long MAXVAL)
{
if (i > MAXVAL || i < j)
return j;
return i;
}
long setcp_min(long a, long b)
{
return (((a) < (b)) ? (a) : (b));
}
void DJLSEncoderBase::setCustomParameters(
JlsCustomParameters& custom,
Uint16 bitsAllocated,
Uint16 nearLosslessDeviation,
const DJLSCodecParameter *djcp)
{
// first check if all parameters are set to default (which will be the most common case).
// In this case we will set everything in the custom struct to zero as well.
if ((djcp->getT1() == 0) && (djcp->getT2() == 0) && (djcp->getT3() == 0) && (djcp->getReset() == 0))
{
custom.T1 = 0;
custom.T2 = 0;
custom.T3 = 0;
custom.RESET = 0;
custom.MAXVAL = 0;
return;
}
// unfortunately, CharLS either takes all or none of the parameters
// in the "custom" struct. So if we change any of them, we need to provide
// legal values for all of them. The function in CharLS that computes these
// values is not public, so we basically have to re-implement it here.
const int BASIC_T1 = 3;
const int BASIC_T2 = 7;
const int BASIC_T3 = 21;
const long BASIC_RESET = 64;
long MAXVAL = (1 << bitsAllocated) - 1;
long FACTOR = (setcp_min(MAXVAL, 4095) + 128)/256;
long NEAR = nearLosslessDeviation;
custom.MAXVAL = MAXVAL;
if (djcp->getT1() > 0) custom.T1 = djcp->getT1(); else
custom.T1 = setcp_clamp(FACTOR * (BASIC_T1 - 2) + 2 + 3*NEAR, NEAR + 1, MAXVAL);
if (djcp->getT2() > 0) custom.T2 = djcp->getT2(); else
custom.T2 = setcp_clamp(FACTOR * (BASIC_T2 - 3) + 3 + 5*NEAR, custom.T1, MAXVAL);
if (djcp->getT3() > 0) custom.T3 = djcp->getT3(); else
custom.T3 = setcp_clamp(FACTOR * (BASIC_T3 - 4) + 4 + 7*NEAR, custom.T2, MAXVAL);
if (djcp->getReset() > 0) custom.RESET = djcp->getReset();
else custom.RESET = BASIC_RESET;
}
OFCondition DJLSEncoderBase::compressRawFrame(
const Uint8 *framePointer,
Uint16 bitsAllocated,
Uint16 width,
Uint16 height,
Uint16 samplesPerPixel,
Uint16 planarConfiguration,
const OFString& /* photometricInterpretation */,
DcmPixelSequence *pixelSequence,
DcmOffsetList &offsetList,
unsigned long &compressedSize,
const DJLSCodecParameter *djcp) const
{
OFCondition result = EC_Normal;
Uint16 bytesAllocated = bitsAllocated / 8;
Uint32 frameSize = width*height*bytesAllocated*samplesPerPixel;
Uint32 fragmentSize = djcp->getFragmentSize();
JlsParameters jls_params;
Uint8 *frameBuffer = NULL;
// Set up the information structure for CharLS
OFBitmanipTemplate<char>::zeroMem((char *) &jls_params, sizeof(jls_params));
jls_params.bitspersample = bitsAllocated;
jls_params.height = height;
jls_params.width = width;
jls_params.allowedlossyerror = 0; // must be zero for raw mode
jls_params.outputBgr = false;
// No idea what this one does, but I don't think DICOM says anything about it
jls_params.colorTransform = 0;
// Unset: jls_params.jfif (thumbnail, dpi)
// set parameters T1, T2, T3, MAXVAL and RESET.
// compressRawFrame() is only used for true lossless mode, so the near-lossless deviation is always 0 here.
setCustomParameters(jls_params.custom, bitsAllocated, 0, djcp);
// Theoretically we could support any samplesPerPixel value, but for now we
// only accept these (charls is a little picky for other values).
if (samplesPerPixel == 1 || samplesPerPixel == 3)
jls_params.components = samplesPerPixel;
else
return EC_IllegalCall;
enum interleavemode ilv;
switch (planarConfiguration)
{
// ILV_LINE is not supported by DICOM
case 0:
ilv = ILV_SAMPLE;
break;
case 1:
ilv = ILV_NONE;
break;
default:
return EC_IllegalCall;
}
switch (djcp->getJplsInterleaveMode())
{
case DJLSCodecParameter::interleaveSample:
jls_params.ilv = ILV_SAMPLE;
break;
case DJLSCodecParameter::interleaveLine:
jls_params.ilv = ILV_LINE;
break;
#ifdef ENABLE_DCMJPLS_INTERLEAVE_NONE
case DJLSCodecParameter::interleaveNone:
jls_params.ilv = ILV_NONE;
break;
#endif
case DJLSCodecParameter::interleaveDefault:
default:
// In default mode we just never convert the image to another
// interleave-mode. Instead, we use what is already there.
#ifdef ENABLE_DCMJPLS_INTERLEAVE_NONE
jls_params.ilv = ilv;
#else
jls_params.ilv = (ilv == ILV_NONE ? ILV_LINE : ilv);
#endif
break;
}
// Special case: one component images are always ILV_NONE (Standard requires this)
if (jls_params.components == 1)
{
jls_params.ilv = ILV_NONE;
// Don't try to convert to another interleave mode, not necessary
ilv = ILV_NONE;
}
// Do we have to convert the image to some other interleave mode?
if ((jls_params.ilv == ILV_NONE && (ilv == ILV_SAMPLE || ilv == ILV_LINE)) ||
(ilv == ILV_NONE && (jls_params.ilv == ILV_SAMPLE || jls_params.ilv == ILV_LINE)))
{
DCMJPLS_DEBUG("converting image from " << (ilv == ILV_NONE ? "color-by-plane" : "color-by-pixel")
<< " to " << (jls_params.ilv == ILV_NONE ? "color-by-plane" : "color-by-pixel"));
frameBuffer = new Uint8[frameSize];
if (jls_params.ilv == ILV_NONE)
result = convertToUninterleaved(frameBuffer, framePointer, samplesPerPixel, width, height, bitsAllocated);
else
/* For CharLS, sample-interleaved and line-interleaved is both expected to
* be color-by-pixel.
*/
result = convertToSampleInterleaved(frameBuffer, framePointer, samplesPerPixel, width, height, bitsAllocated);
framePointer = frameBuffer;
}
if (result.good())
{
// The buffer is going to be dynamically reallocated if it's too small, so it doesn't matter that
// much what initial size we use.
size_t size = frameSize + 1024;
BYTE *buffer = new BYTE[size];
size_t bytesWritten = 0;
JLS_ERROR err = JpegLsEncode(&buffer, &size, &bytesWritten, framePointer, frameSize, &jls_params);
result = DJLSError::convert(err);
if (result.good())
{
compressedSize = OFstatic_cast(unsigned long, bytesWritten);
fixPaddingIfNecessary(OFstatic_cast(Uint8 *, buffer), size, compressedSize, djcp->getUseFFbitstreamPadding());
result = pixelSequence->storeCompressedFrame(offsetList, buffer, compressedSize, fragmentSize);
}
delete[] buffer;
}
if (frameBuffer)
delete[] frameBuffer;
return result;
}
OFCondition DJLSEncoderBase::losslessCookedEncode(
const Uint16 *pixelData,
const Uint32 length,
DcmItem *dataset,
const DJLSRepresentationParameter *djrp,
DcmPixelSequence * & pixSeq,
const DJLSCodecParameter *djcp,
double& compressionRatio,
Uint16 nearLosslessDeviation) const
{
compressionRatio = 0.0; // initialize if something goes wrong
// determine a few image properties
OFString photometricInterpretation;
Uint16 bitsAllocated = 0;
OFCondition result = dataset->findAndGetOFString(DCM_PhotometricInterpretation, photometricInterpretation);
if (result.good()) result = dataset->findAndGetUint16(DCM_BitsAllocated, bitsAllocated);
if (result.bad()) return result;
// The cooked encoder only handles the following photometric interpretations
if (photometricInterpretation != "MONOCHROME1" &&
photometricInterpretation != "MONOCHROME2" &&
photometricInterpretation != "RGB" &&
photometricInterpretation != "YBR_FULL")
{
// a photometric interpretation that we don't handle. Fall back to raw encoder (unless in near-lossless mode)
if (nearLosslessDeviation > 0) return EC_JLSUnsupportedPhotometricInterpretation;
else return losslessRawEncode(pixelData, length, dataset, djrp, pixSeq, djcp, compressionRatio);
}
Uint16 pixelRepresentation = 0;
result = dataset->findAndGetUint16(DCM_PixelRepresentation, pixelRepresentation);
if (result.bad()) return result;
if (pixelRepresentation > 0)
{
// in near lossless mode we cannot handle signed images because JPEG-LS assumes unsigned pixels
if (nearLosslessDeviation > 0) return EC_JLSUnsupportedPixelRepresentation;
// The cooked encoder only handles unsigned color images
if (photometricInterpretation == "RGB" || photometricInterpretation == "YBR_FULL")
{
// prevent a loop - only call lossless raw encoder if bitsAllocated is OK for the raw encoder
if ((bitsAllocated == 8) || (bitsAllocated == 16))
return losslessRawEncode(pixelData, length, dataset, djrp, pixSeq, djcp, compressionRatio);
else return EC_JLSUnsupportedPixelRepresentation;
}
}
// Check if image is 2..16 bits/sample, bail out otherwise.
// We check the value of BitsStored, which is not affected by any transformation such as MLUT.
Uint16 bitsStored = 0;
result = dataset->findAndGetUint16(DCM_BitsStored, bitsStored);
if (result.bad()) return result;
if (bitsStored > 16)
{
DCMJPLS_WARN("cannot compress image with " << bitsStored << " bits/sample: JPEG-LS supports max. 16 bits");
return EC_JLSUnsupportedBitDepth;
}
if (bitsStored < 2)
{
DCMJPLS_WARN("cannot compress image with " << bitsStored << " bit/sample: JPEG-LS requires at least 2 bits");
return EC_JLSUnsupportedBitDepth;
}
DcmPixelSequence *pixelSequence = NULL;
DcmPixelItem *offsetTable = NULL;
// ignore modality transformation (rescale slope/intercept or LUT) stored in the dataset
unsigned long flags = CIF_IgnoreModalityTransformation;
// don't convert YCbCr (Full and Full 4:2:2) color images to RGB
flags |= CIF_KeepYCbCrColorModel;
// Don't optimize memory usage, but keep using the same bitsAllocated.
// Without this, the DICOM and the JPEG-LS value for bitsAllocated could
// differ and the decoder would error out.
flags |= CIF_UseAbsolutePixelRange;
DicomImage *dimage = new DicomImage(dataset, EXS_LittleEndianImplicit, flags); // read all frames
if (dimage == NULL) return EC_MemoryExhausted;
if (dimage->getStatus() != EIS_Normal)
{
delete dimage;
return EC_IllegalCall;
}
// create overlay data for embedded overlays
result = adjustOverlays(dataset, *dimage);
// determine number of bits per sample
int bitsPerSample = dimage->getDepth();
// create initial pixel sequence
if (result.good())
{
pixelSequence = new DcmPixelSequence(DCM_PixelSequenceTag);
if (pixelSequence == NULL) result = EC_MemoryExhausted;
else
{
// create empty offset table
offsetTable = new DcmPixelItem(DCM_PixelItemTag);
if (offsetTable == NULL) result = EC_MemoryExhausted;
else pixelSequence->insert(offsetTable);
}
}
DcmOffsetList offsetList;
unsigned long compressedSize = 0;
unsigned long compressedFrameSize = 0;
double uncompressedSize = 0.0;
// render and compress each frame
if (result.good())
{
unsigned long frameCount = dimage->getFrameCount();
// compute original image size in bytes, ignoring any padding bits.
Uint16 samplesPerPixel = 0;
if ((dataset->findAndGetUint16(DCM_SamplesPerPixel, samplesPerPixel)).bad()) samplesPerPixel = 1;
uncompressedSize = dimage->getWidth() * dimage->getHeight() *
bitsPerSample * frameCount * samplesPerPixel / 8.0;
for (unsigned long i=0; (i<frameCount) && (result.good()); ++i)
{
// compress frame
DCMJPLS_DEBUG("JPEG-LS encoder processes frame " << (i+1) << " of " << frameCount);
result = compressCookedFrame(pixelSequence, dimage,
photometricInterpretation, offsetList, compressedFrameSize, djcp, i, nearLosslessDeviation);
compressedSize += compressedFrameSize;
}
}
// store pixel sequence if everything went well.
if (result.good()) pixSeq = pixelSequence;
else
{
delete pixelSequence;
pixSeq = NULL;
}
// create offset table
if ((result.good()) && (djcp->getCreateOffsetTable()))
{
result = offsetTable->createOffsetTable(offsetList);
}
// adapt attributes in image pixel module
if (result.good())
{
// adjustments needed for both color and monochrome
if (bitsPerSample > 8)
result = dataset->putAndInsertUint16(DCM_BitsAllocated, 16);
else
result = dataset->putAndInsertUint16(DCM_BitsAllocated, 8);
if (result.good()) result = dataset->putAndInsertUint16(DCM_BitsStored, OFstatic_cast(Uint16, bitsPerSample));
if (result.good()) result = dataset->putAndInsertUint16(DCM_HighBit, OFstatic_cast(Uint16, (bitsPerSample-1)));
if (result.good())
{
if (photometricInterpretation == "RGB" || photometricInterpretation == "YBR_FULL")
{
// CP 1843 requires a planar configuration value of 0 for these color models
result = dataset->putAndInsertUint16(DCM_PlanarConfiguration, 0);
}
else
{
// this is monochrome since we have ruled out all other photometric interpretations
// at the start of this method
delete dataset->remove(DCM_PlanarConfiguration);
}
}
}
if (compressedSize > 0) compressionRatio = uncompressedSize / compressedSize;
delete dimage;
return result;
}
OFCondition DJLSEncoderBase::compressCookedFrame(
DcmPixelSequence *pixelSequence,
DicomImage *dimage,
const OFString& /* photometricInterpretation */,
DcmOffsetList &offsetList,
unsigned long &compressedSize,
const DJLSCodecParameter *djcp,
Uint32 frame,
Uint16 nearLosslessDeviation) const
{
if (dimage == NULL) return EC_IllegalCall;
// access essential image parameters
int width = dimage->getWidth();
int height = dimage->getHeight();
int depth = dimage->getDepth();
if ((depth < 1) || (depth > 16)) return EC_JLSUnsupportedBitDepth;
Uint32 fragmentSize = djcp->getFragmentSize();
const DiPixel *dinter = dimage->getInterData();
if (dinter == NULL) return EC_IllegalCall;
// There should be no other possibilities
int samplesPerPixel = dinter->getPlanes();
if (samplesPerPixel != 1 && samplesPerPixel != 3) return EC_IllegalCall;
// get pointer to internal raw representation of image data
const void *draw = dinter->getData();
if (draw == NULL) return EC_IllegalCall;
OFCondition result = EC_Normal;
const void *planes[3] = {NULL, NULL, NULL};
if (samplesPerPixel == 3)
{
// for color images, dinter->getData() returns a pointer to an array
// of pointers pointing to the real plane data
const void * const * draw_array = OFstatic_cast(const void * const *,draw);
planes[0] = draw_array[0];
planes[1] = draw_array[1];
planes[2] = draw_array[2];
}
else
{
// for monochrome images, dinter->getData() directly returns a pointer
// to the single monochrome plane.
planes[0] = draw;
}
// This is the buffer with the uncompressed pixel data
Uint8 *buffer;
size_t buffer_size;
Uint32 framesize = dimage->getWidth() * dimage->getHeight();
switch(dinter->getRepresentation())
{
case EPR_Uint8:
case EPR_Sint8:
{
// image representation is 8 bit signed or unsigned
if (samplesPerPixel == 1)
{
const Uint8 *yv = OFreinterpret_cast(const Uint8 *, planes[0]) + framesize * frame;
buffer_size = framesize;
buffer = new Uint8[buffer_size];
memcpy(buffer, yv, framesize);
}
else
{
const Uint8 *rv = OFreinterpret_cast(const Uint8 *, planes[0]) + framesize * frame;
const Uint8 *gv = OFreinterpret_cast(const Uint8 *, planes[1]) + framesize * frame;
const Uint8 *bv = OFreinterpret_cast(const Uint8 *, planes[2]) + framesize * frame;
buffer_size = framesize * 3;
buffer = new Uint8[buffer_size];
size_t i = 0;
for (int row=height; row; --row)
{
for (int col=width; col; --col)
{
buffer[i++] = *rv;
buffer[i++] = *gv;
buffer[i++] = *bv;
rv++;
gv++;
bv++;
}
}
}
}
break;
case EPR_Uint16:
case EPR_Sint16:
{
// image representation is 16 bit signed or unsigned
if (samplesPerPixel == 1)
{
const Uint16 *yv = OFreinterpret_cast(const Uint16 *, planes[0]) + framesize * frame;
buffer_size = framesize*sizeof(Uint16);
buffer = new Uint8[buffer_size];
memcpy(buffer, yv, buffer_size);
}
else
{
const Uint16 *rv = OFreinterpret_cast(const Uint16 *, planes[0]) + framesize * frame;
const Uint16 *gv = OFreinterpret_cast(const Uint16 *, planes[1]) + framesize * frame;
const Uint16 *bv = OFreinterpret_cast(const Uint16 *, planes[2]) + framesize * frame;
buffer_size = framesize * 3;
Uint16 *buffer16 = new Uint16[buffer_size];
buffer = OFreinterpret_cast(Uint8 *, buffer16);
// Convert to byte count
buffer_size *= 2;
size_t i = 0;
for (int row=height; row; --row)
{
for (int col=width; col; --col)
{
buffer16[i++] = *rv;
buffer16[i++] = *gv;
buffer16[i++] = *bv;
rv++;
gv++;
bv++;
}
}
}
}
break;
default:
// we don't support images with > 16 bits/sample
return EC_JLSUnsupportedBitDepth;
break;
}
JlsParameters jls_params;
// Set up the information structure for CharLS
OFBitmanipTemplate<char>::zeroMem((char *) &jls_params, sizeof(jls_params));
jls_params.height = height;
jls_params.width = width;
jls_params.allowedlossyerror = nearLosslessDeviation;
jls_params.outputBgr = false;
jls_params.bitspersample = depth;
// No idea what this one does, but I don't think DICOM says anything about it
jls_params.colorTransform = 0;
// This was already checked for a sane value above
jls_params.components = samplesPerPixel;
// Unset: jls_params.jfif (thumbnail, dpi)
// set parameters T1, T2, T3, MAXVAL and RESET
setCustomParameters(jls_params.custom, OFstatic_cast(Uint16, depth), nearLosslessDeviation, djcp);
switch (djcp->getJplsInterleaveMode())
{
case DJLSCodecParameter::interleaveSample:
jls_params.ilv = ILV_SAMPLE;
break;
case DJLSCodecParameter::interleaveLine:
jls_params.ilv = ILV_LINE;
break;
#ifdef ENABLE_DCMJPLS_INTERLEAVE_NONE
case DJLSCodecParameter::interleaveNone:
jls_params.ilv = ILV_NONE;
break;
#endif
case DJLSCodecParameter::interleaveDefault:
default:
// Default for the cooked encoder is always ILV_LINE
jls_params.ilv = ILV_LINE;
break;
}
// Special case: one component images are always ILV_NONE (Standard requires this)
if (jls_params.components == 1)
{
jls_params.ilv = ILV_NONE;
}
Uint8 *frameBuffer = NULL;
Uint8 *framePointer = buffer;
#ifdef ENABLE_DCMJPLS_INTERLEAVE_NONE
// Do we have to convert the image to color-by-plane now?
if (jls_params.ilv == ILV_NONE && jls_params.components != 1)
{
DCMJPLS_DEBUG("converting image from color-by-pixel to color-by-plane");
frameBuffer = new Uint8[buffer_size];
framePointer = frameBuffer;
result = convertToUninterleaved(frameBuffer, buffer, OFstatic_cast(Uint16, samplesPerPixel), width, height, OFstatic_cast(Uint16, jls_params.bitspersample));
}
#endif
size_t compressed_buffer_size = buffer_size + 1024;
BYTE *compressed_buffer = new BYTE[compressed_buffer_size];
size_t bytesWritten = 0;
JLS_ERROR err = JpegLsEncode(&compressed_buffer, &compressed_buffer_size, &bytesWritten, framePointer, buffer_size, &jls_params);
result = DJLSError::convert(err);
if (result.good())
{
// 'compressed_buffer_size' now contains the size of the compressed data in buffer
compressedSize = OFstatic_cast(unsigned long, bytesWritten);
fixPaddingIfNecessary(OFstatic_cast(Uint8 *, buffer), compressed_buffer_size, compressedSize, djcp->getUseFFbitstreamPadding());
result = pixelSequence->storeCompressedFrame(offsetList, compressed_buffer, compressedSize, fragmentSize);
}
delete[] buffer;
delete[] compressed_buffer;
if (frameBuffer)
delete[] frameBuffer;
return result;
}
OFCondition DJLSEncoderBase::convertToUninterleaved(
Uint8 *target,
const Uint8 *source,
Uint16 components,
Uint32 width,
Uint32 height,
Uint16 bitsAllocated) const
{
Uint8 bytesAllocated = OFstatic_cast(Uint8, (bitsAllocated / 8));
Uint32 planeSize = width * height * bytesAllocated;
if (bitsAllocated % 8 != 0)
return EC_IllegalCall;
for (Uint32 pos = 0; pos < width * height; pos++)
{
for (int i = 0; i < components; i++)
{
memcpy(&target[i * planeSize + pos * bytesAllocated], source, bytesAllocated);
source += bytesAllocated;
}
}
return EC_Normal;
}
OFCondition DJLSEncoderBase::convertToSampleInterleaved(
Uint8 *target,
const Uint8 *source,
Uint16 components,
Uint32 width,
Uint32 height,
Uint16 bitsAllocated) const
{
Uint8 bytesAllocated = OFstatic_cast(Uint8, (bitsAllocated / 8));
Uint32 planeSize = width * height * bytesAllocated;
if (bitsAllocated % 8 != 0)
return EC_IllegalCall;
for (Uint32 pos = 0; pos < width * height; pos++)
{
for (int i = 0; i < components; i++)
{
memcpy(target, &source[i * planeSize + pos * bytesAllocated], bytesAllocated);
target += bytesAllocated;
}
}
return EC_Normal;
}
void DJLSEncoderBase::fixPaddingIfNecessary(
Uint8 *buffer,
size_t bufSize,
unsigned long &bytesWritten,
OFBool useFFpadding)
{
// check if an odd number of bytes was written and the buffer
// has space for the needed pad byte (which should in practice
// always be the case because the buffer always has even length).
if (buffer && ((bytesWritten % 2 )> 0) && (bufSize > bytesWritten))
{
// first write a zero pad byte after the end of the JPEG-LS bitstream
buffer[bytesWritten++] = 0;
// check if we are expected to use an extended EOI marker for padding
if (useFFpadding)
{
// look for the EOI marker
if ((bytesWritten > 2) && (buffer[bytesWritten-3] == 0xFF) && (buffer[bytesWritten-2] == 0xD9))
{
// we now have ff/d9/00 at the end of the JPEG bitstream,
// i.e. an end of image (EOI) marker followed by a pad byte.
// Replace this with ff/ff/d9, which is an "extended" EOI marker
// ending on an even byte boundary.
buffer[bytesWritten-2] = 0xFF;
buffer[bytesWritten-1] = 0xD9;
}
}
}
return;
}
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