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-rw-r--r--src/3rdparty/libmng/libmng_filter.c978
1 files changed, 978 insertions, 0 deletions
diff --git a/src/3rdparty/libmng/libmng_filter.c b/src/3rdparty/libmng/libmng_filter.c
new file mode 100644
index 0000000000..ed69a75340
--- /dev/null
+++ b/src/3rdparty/libmng/libmng_filter.c
@@ -0,0 +1,978 @@
+/* ************************************************************************** */
+/* * For conditions of distribution and use, * */
+/* * see copyright notice in libmng.h * */
+/* ************************************************************************** */
+/* * * */
+/* * project : libmng * */
+/* * file : libmng_filter.c copyright (c) 2000-2004 G.Juyn * */
+/* * version : 1.0.9 * */
+/* * * */
+/* * purpose : Filtering routines (implementation) * */
+/* * * */
+/* * author : G.Juyn * */
+/* * * */
+/* * comment : implementation of the filtering routines * */
+/* * * */
+/* * changes : 0.5.1 - 05/08/2000 - G.Juyn * */
+/* * - changed strict-ANSI stuff * */
+/* * 0.5.1 - 05/12/2000 - G.Juyn * */
+/* * - changed trace to macro for callback error-reporting * */
+/* * * */
+/* * 0.9.2 - 08/05/2000 - G.Juyn * */
+/* * - changed file-prefixes * */
+/* * * */
+/* * 0.9.3 - 09/07/2000 - G.Juyn * */
+/* * - added support for new filter_types * */
+/* * * */
+/* * 1.0.5 - 08/07/2002 - G.Juyn * */
+/* * - added test-option for PNG filter method 193 (=no filter) * */
+/* * 1.0.5 - 08/19/2002 - G.Juyn * */
+/* * - B597134 - libmng pollutes the linker namespace * */
+/* * * */
+/* * 1.0.6 - 07/07/2003 - G.R-P * */
+/* * - reversed some loops to use decrementing counter * */
+/* * * */
+/* * 1.0.9 - 12/20/2004 - G.Juyn * */
+/* * - cleaned up macro-invocations (thanks to D. Airlie) * */
+/* * * */
+/* ************************************************************************** */
+
+#include "libmng.h"
+#include "libmng_data.h"
+#include "libmng_error.h"
+#include "libmng_trace.h"
+#ifdef __BORLANDC__
+#pragma hdrstop
+#endif
+#include "libmng_filter.h"
+
+#if defined(__BORLANDC__) && defined(MNG_STRICT_ANSI)
+#pragma option -A /* force ANSI-C */
+#endif
+
+/* ************************************************************************** */
+
+#ifdef MNG_INCLUDE_FILTERS
+
+/* ************************************************************************** */
+
+MNG_LOCAL mng_retcode filter_sub (mng_datap pData)
+{
+ mng_uint32 iBpp;
+ mng_uint8p pRawx;
+ mng_uint8p pRawx_prev;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_FILTER_SUB, MNG_LC_START);
+#endif
+
+ iBpp = pData->iFilterbpp;
+ pRawx = pData->pWorkrow + pData->iPixelofs + iBpp;
+ pRawx_prev = pData->pWorkrow + pData->iPixelofs;
+
+ for (iX = iBpp; iX < pData->iRowsize; iX++)
+ {
+ *pRawx = (mng_uint8)(*pRawx + *pRawx_prev);
+ pRawx++;
+ pRawx_prev++;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_FILTER_SUB, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+MNG_LOCAL mng_retcode filter_up (mng_datap pData)
+{
+ mng_uint8p pRawx;
+ mng_uint8p pPriorx;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_FILTER_UP, MNG_LC_START);
+#endif
+
+ pRawx = pData->pWorkrow + pData->iPixelofs;
+ pPriorx = pData->pPrevrow + pData->iPixelofs;
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsize - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsize; iX++)
+#endif
+ {
+ *pRawx = (mng_uint8)(*pRawx + *pPriorx);
+ pRawx++;
+ pPriorx++;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_FILTER_UP, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+MNG_LOCAL mng_retcode filter_average (mng_datap pData)
+{
+ mng_int32 iBpp;
+ mng_uint8p pRawx;
+ mng_uint8p pRawx_prev;
+ mng_uint8p pPriorx;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_FILTER_AVERAGE, MNG_LC_START);
+#endif
+
+ iBpp = pData->iFilterbpp;
+ pRawx = pData->pWorkrow + pData->iPixelofs;
+ pPriorx = pData->pPrevrow + pData->iPixelofs;
+ pRawx_prev = pData->pWorkrow + pData->iPixelofs;
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = iBpp - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < iBpp; iX++)
+#endif
+ {
+ *pRawx = (mng_uint8)(*pRawx + ((*pPriorx) >> 1));
+ pRawx++;
+ pPriorx++;
+ }
+
+ for (iX = iBpp; iX < pData->iRowsize; iX++)
+ {
+ *pRawx = (mng_uint8)(*pRawx + ((*pRawx_prev + *pPriorx) >> 1));
+ pRawx++;
+ pPriorx++;
+ pRawx_prev++;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_FILTER_AVERAGE, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+MNG_LOCAL mng_retcode filter_paeth (mng_datap pData)
+{
+ mng_int32 iBpp;
+ mng_uint8p pRawx;
+ mng_uint8p pRawx_prev;
+ mng_uint8p pPriorx;
+ mng_uint8p pPriorx_prev;
+ mng_int32 iX;
+ mng_uint32 iA, iB, iC;
+ mng_uint32 iP;
+ mng_uint32 iPa, iPb, iPc;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_FILTER_PAETH, MNG_LC_START);
+#endif
+
+ iBpp = pData->iFilterbpp;
+ pRawx = pData->pWorkrow + pData->iPixelofs;
+ pPriorx = pData->pPrevrow + pData->iPixelofs;
+ pRawx_prev = pData->pWorkrow + pData->iPixelofs;
+ pPriorx_prev = pData->pPrevrow + pData->iPixelofs;
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = iBpp - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < iBpp; iX++)
+#endif
+ {
+ *pRawx = (mng_uint8)(*pRawx + *pPriorx);
+
+ pRawx++;
+ pPriorx++;
+ }
+
+ for (iX = iBpp; iX < pData->iRowsize; iX++)
+ {
+ iA = (mng_uint32)*pRawx_prev;
+ iB = (mng_uint32)*pPriorx;
+ iC = (mng_uint32)*pPriorx_prev;
+ iP = iA + iB - iC;
+ iPa = abs (iP - iA);
+ iPb = abs (iP - iB);
+ iPc = abs (iP - iC);
+
+ if ((iPa <= iPb) && (iPa <= iPc))
+ *pRawx = (mng_uint8)(*pRawx + iA);
+ else
+ if (iPb <= iPc)
+ *pRawx = (mng_uint8)(*pRawx + iB);
+ else
+ *pRawx = (mng_uint8)(*pRawx + iC);
+
+ pRawx++;
+ pPriorx++;
+ pRawx_prev++;
+ pPriorx_prev++;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_FILTER_PAETH, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_filter_a_row (mng_datap pData)
+{
+ mng_retcode iRetcode;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_FILTER_A_ROW, MNG_LC_START);
+#endif
+
+ switch (*(pData->pWorkrow + pData->iFilterofs))
+ {
+ case 1 : {
+ iRetcode = filter_sub (pData);
+ break;
+ }
+ case 2 : {
+ iRetcode = filter_up (pData);
+ break;
+ }
+ case 3 : {
+ iRetcode = filter_average (pData);
+ break;
+ }
+ case 4 : {
+ iRetcode = filter_paeth (pData);
+ break;
+ }
+
+ default : iRetcode = MNG_INVALIDFILTER;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_FILTER_A_ROW, MNG_LC_END);
+#endif
+
+ return iRetcode;
+}
+
+/* ************************************************************************** */
+/* ************************************************************************** */
+
+#ifdef FILTER192
+mng_retcode mng_init_rowdiffering (mng_datap pData)
+{
+ mng_uint8p pRawi, pRawo;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_INIT_ROWDIFFERING, MNG_LC_START);
+#endif
+
+ if (pData->iFilter == 0xC0) /* has leveling parameters ? */
+ {
+ switch (pData->iColortype) /* salvage leveling parameters */
+ {
+ case 0 : { /* gray */
+ if (pData->iBitdepth <= 8)
+ pData->iLevel0 = (mng_uint16)*pData->pWorkrow;
+ else
+ pData->iLevel0 = mng_get_uint16 (pData->pWorkrow);
+
+ break;
+ }
+ case 2 : { /* rgb */
+ if (pData->iBitdepth <= 8)
+ {
+ pData->iLevel0 = (mng_uint16)*pData->pWorkrow;
+ pData->iLevel1 = (mng_uint16)*(pData->pWorkrow+1);
+ pData->iLevel2 = (mng_uint16)*(pData->pWorkrow+2);
+ }
+ else
+ {
+ pData->iLevel0 = mng_get_uint16 (pData->pWorkrow);
+ pData->iLevel1 = mng_get_uint16 (pData->pWorkrow+2);
+ pData->iLevel2 = mng_get_uint16 (pData->pWorkrow+4);
+ }
+
+ break;
+ }
+ case 3 : { /* indexed */
+ pData->iLevel0 = (mng_uint16)*pData->pWorkrow;
+ break;
+ }
+ case 4 : { /* gray+alpha */
+ if (pData->iBitdepth <= 8)
+ {
+ pData->iLevel0 = (mng_uint16)*pData->pWorkrow;
+ pData->iLevel1 = (mng_uint16)*(pData->pWorkrow+1);
+ }
+ else
+ {
+ pData->iLevel0 = mng_get_uint16 (pData->pWorkrow);
+ pData->iLevel1 = mng_get_uint16 (pData->pWorkrow+2);
+ }
+
+ break;
+ }
+ case 6 : { /* rgb+alpha */
+ if (pData->iBitdepth <= 8)
+ {
+ pData->iLevel0 = (mng_uint16)*pData->pWorkrow;
+ pData->iLevel1 = (mng_uint16)*(pData->pWorkrow+1);
+ pData->iLevel2 = (mng_uint16)*(pData->pWorkrow+2);
+ pData->iLevel3 = (mng_uint16)*(pData->pWorkrow+3);
+ }
+ else
+ {
+ pData->iLevel0 = mng_get_uint16 (pData->pWorkrow);
+ pData->iLevel1 = mng_get_uint16 (pData->pWorkrow+2);
+ pData->iLevel2 = mng_get_uint16 (pData->pWorkrow+4);
+ pData->iLevel3 = mng_get_uint16 (pData->pWorkrow+6);
+ }
+
+ break;
+ }
+ }
+ }
+ /* shift the entire row back in place */
+ pRawi = pData->pWorkrow + pData->iFilterofs;
+ pRawo = pData->pWorkrow;
+
+ for (iX = 0; iX < pData->iRowsize + pData->iPixelofs - pData->iFilterofs; iX++)
+ *pRawo++ = *pRawi++;
+
+ pData->iFilterofs = 0; /* indicate so ! */
+
+#ifdef FILTER193
+ if (pData->iFilter == 0xC1) /* no adaptive filtering ? */
+ pData->iPixelofs = pData->iFilterofs;
+ else
+#endif
+ pData->iPixelofs = pData->iFilterofs + 1;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_INIT_ROWDIFFERING, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_g1 (mng_datap pData)
+{
+ mng_uint8p pRawi, pRawo;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_G1, MNG_LC_START);
+#endif
+
+ if (pData->iLevel0 & 0x01) /* is it uneven level ? */
+ {
+ pRawi = pData->pWorkrow + pData->iPixelofs;
+ pRawo = pData->pPrevrow + pData->iPixelofs;
+ /* just invert every bit */
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsize - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsize; iX++)
+#endif
+ *pRawo++ = (mng_uint8)(~(*pRawi++));
+
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_G1, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_g2 (mng_datap pData)
+{
+ mng_uint8p pRawi, pRawo;
+ mng_int32 iX;
+ mng_int32 iC, iS;
+ mng_uint8 iB, iN, iQ;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_G2, MNG_LC_START);
+#endif
+
+ pRawi = pData->pWorkrow + pData->iPixelofs;
+ pRawo = pData->pPrevrow + pData->iPixelofs;
+ iC = 0;
+ iB = 0;
+ iN = 0;
+ iS = 0;
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsamples - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsamples; iX++)
+#endif
+ {
+ if (!iC)
+ {
+ iC = 4;
+ iB = *pRawi++;
+ iN = 0;
+ iS = 8;
+ }
+
+ iS -= 2;
+ iQ = (mng_uint8)(((iB >> iS) + pData->iLevel0) & 0x03);
+ iN = (mng_uint8)((iN << 2) + iQ);
+ iC--;
+
+ if (!iC)
+ *pRawo++ = iN;
+
+ }
+
+ if (iC)
+ *pRawo = (mng_uint8)(iN << iS);
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_G2, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_g4 (mng_datap pData)
+{
+ mng_uint8p pRawi, pRawo;
+ mng_int32 iX;
+ mng_int32 iC, iS;
+ mng_uint8 iB, iN, iQ;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_G4, MNG_LC_START);
+#endif
+
+ pRawi = pData->pWorkrow + pData->iPixelofs;
+ pRawo = pData->pPrevrow + pData->iPixelofs;
+ iC = 0;
+ iB = 0;
+ iN = 0;
+ iS = 0;
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsamples - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsamples; iX++)
+#endif
+ {
+ if (!iC)
+ {
+ iC = 2;
+ iB = *pRawi++;
+ iN = 0;
+ iS = 8;
+ }
+
+ iS -= 4;
+ iQ = (mng_uint8)(((iB >> iS) + pData->iLevel0) & 0x0F);
+ iN = (mng_uint8)((iN << 4) + iQ);
+ iC--;
+
+ if (!iC)
+ *pRawo++ = iN;
+
+ }
+
+ if (iC)
+ *pRawo = (mng_uint8)(iN << iS);
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_G4, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_g8 (mng_datap pData)
+{
+ mng_uint8p pRawi, pRawo;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_G8, MNG_LC_START);
+#endif
+
+ pRawi = pData->pWorkrow + pData->iPixelofs;
+ pRawo = pData->pPrevrow + pData->iPixelofs;
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsamples - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsamples; iX++)
+#endif
+ {
+ *pRawo++ = (mng_uint8)(((mng_uint16)*pRawi + pData->iLevel0) & 0xFF);
+
+ pRawi++;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_G8, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_g16 (mng_datap pData)
+{
+ mng_uint16p pRawi, pRawo;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_G16, MNG_LC_START);
+#endif
+
+ pRawi = (mng_uint16p)(pData->pWorkrow + pData->iPixelofs);
+ pRawo = (mng_uint16p)(pData->pPrevrow + pData->iPixelofs);
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsamples - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsamples; iX++)
+#endif
+ {
+ *pRawo++ = (mng_uint16)(((mng_uint32)*pRawi + (mng_uint32)pData->iLevel0) & 0xFFFF);
+
+ pRawi++;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_G16, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_rgb8 (mng_datap pData)
+{
+ mng_uint8p pRawi, pRawo;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_RGB8, MNG_LC_START);
+#endif
+
+ pRawi = pData->pWorkrow + pData->iPixelofs;
+ pRawo = pData->pPrevrow + pData->iPixelofs;
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsamples - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsamples; iX++)
+#endif
+ {
+ *(pRawo+1) = (mng_uint8)(((mng_uint16)*(pRawi+1) + pData->iLevel1) & 0xFF);
+ *pRawo = (mng_uint8)(((mng_uint16)*pRawi + pData->iLevel0 +
+ (mng_uint16)*(pRawo+1)) & 0xFF);
+ *(pRawo+2) = (mng_uint8)(((mng_uint16)*(pRawi+2) + pData->iLevel2 +
+ (mng_uint16)*(pRawo+1)) & 0xFF);
+
+ pRawi += 3;
+ pRawo += 3;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_RGB8, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_rgb16 (mng_datap pData)
+{
+ mng_uint16p pRawi, pRawo;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_RGB16, MNG_LC_START);
+#endif
+
+ pRawi = (mng_uint16p)(pData->pWorkrow + pData->iPixelofs);
+ pRawo = (mng_uint16p)(pData->pPrevrow + pData->iPixelofs);
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsamples - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsamples; iX++)
+#endif
+ {
+ *(pRawo+1) = (mng_uint16)(((mng_uint32)*(pRawi+1) + (mng_uint32)pData->iLevel1) & 0xFFFF);
+ *pRawo = (mng_uint16)(((mng_uint32)*pRawi + (mng_uint32)pData->iLevel0 +
+ (mng_uint32)*(pRawo+1)) & 0xFFFF);
+ *(pRawo+2) = (mng_uint16)(((mng_uint32)*(pRawi+2) + (mng_uint32)pData->iLevel2 +
+ (mng_uint32)*(pRawo+1)) & 0xFFFF);
+
+ pRawi += 3;
+ pRawo += 3;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_RGB16, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_idx1 (mng_datap pData)
+{
+ mng_uint8p pRawi, pRawo;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_IDX1, MNG_LC_START);
+#endif
+
+ if (pData->iLevel0 & 0x01) /* is it uneven level ? */
+ {
+ pRawi = pData->pWorkrow + pData->iPixelofs;
+ pRawo = pData->pPrevrow + pData->iPixelofs;
+ /* just invert every bit */
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsize - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsize; iX++)
+#endif
+ *pRawo++ = (mng_uint8)(~(*pRawi++));
+
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_IDX1, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_idx2 (mng_datap pData)
+{
+ mng_uint8p pRawi, pRawo;
+ mng_int32 iX;
+ mng_int32 iC, iS;
+ mng_uint8 iB, iN, iQ;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_IDX2, MNG_LC_START);
+#endif
+
+ pRawi = pData->pWorkrow + pData->iPixelofs;
+ pRawo = pData->pPrevrow + pData->iPixelofs;
+ iC = 0;
+ iB = 0;
+ iN = 0;
+ iS = 0;
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsamples - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsamples; iX++)
+#endif
+ {
+ if (!iC)
+ {
+ iC = 4;
+ iB = *pRawi++;
+ iN = 0;
+ iS = 8;
+ }
+
+ iS -= 2;
+ iQ = (mng_uint8)(((iB >> iS) + pData->iLevel0) & 0x03);
+ iN = (mng_uint8)((iN << 2) + iQ);
+ iC--;
+
+ if (!iC)
+ *pRawo++ = iN;
+
+ }
+
+ if (iC)
+ *pRawo = (mng_uint8)(iN << iS);
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_IDX2, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_idx4 (mng_datap pData)
+{
+ mng_uint8p pRawi, pRawo;
+ mng_int32 iX;
+ mng_int32 iC, iS;
+ mng_uint8 iB, iN, iQ;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_IDX4, MNG_LC_START);
+#endif
+
+ pRawi = pData->pWorkrow + pData->iPixelofs;
+ pRawo = pData->pPrevrow + pData->iPixelofs;
+ iC = 0;
+ iB = 0;
+ iN = 0;
+ iS = 0;
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsamples - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsamples; iX++)
+#endif
+ {
+ if (!iC)
+ {
+ iC = 2;
+ iB = *pRawi++;
+ iN = 0;
+ iS = 8;
+ }
+
+ iS -= 4;
+ iQ = (mng_uint8)(((iB >> iS) + pData->iLevel0) & 0x0F);
+ iN = (mng_uint8)((iN << 4) + iQ);
+ iC--;
+
+ if (!iC)
+ *pRawo++ = iN;
+
+ }
+
+ if (iC)
+ *pRawo = (mng_uint8)(iN << iS);
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_IDX4, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_idx8 (mng_datap pData)
+{
+ mng_uint8p pRawi, pRawo;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_IDX8, MNG_LC_START);
+#endif
+
+ pRawi = pData->pWorkrow + pData->iPixelofs;
+ pRawo = pData->pPrevrow + pData->iPixelofs;
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsamples - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsamples; iX++)
+#endif
+ {
+ *pRawo++ = (mng_uint8)(((mng_uint16)*pRawi + pData->iLevel0) & 0xFF);
+
+ pRawi++;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_IDX8, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_ga8 (mng_datap pData)
+{
+ mng_uint8p pRawi, pRawo;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_GA8, MNG_LC_START);
+#endif
+
+ pRawi = pData->pWorkrow + pData->iPixelofs;
+ pRawo = pData->pPrevrow + pData->iPixelofs;
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsamples - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsamples; iX++)
+#endif
+ {
+ *pRawo = (mng_uint8)(((mng_uint16)*pRawi + pData->iLevel0) & 0xFF);
+ *(pRawo+1) = (mng_uint8)(((mng_uint16)*(pRawi+1) + pData->iLevel1) & 0xFF);
+
+ pRawi += 2;
+ pRawo += 2;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_GA8, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_ga16 (mng_datap pData)
+{
+ mng_uint16p pRawi, pRawo;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_GA16, MNG_LC_START);
+#endif
+
+ pRawi = (mng_uint16p)(pData->pWorkrow + pData->iPixelofs);
+ pRawo = (mng_uint16p)(pData->pPrevrow + pData->iPixelofs);
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsamples - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsamples; iX++)
+#endif
+ {
+ *pRawo = (mng_uint16)(((mng_uint32)*pRawi + (mng_uint32)pData->iLevel0) & 0xFFFF);
+ *(pRawo+1) = (mng_uint16)(((mng_uint32)*(pRawi+1) + (mng_uint32)pData->iLevel1) & 0xFFFF);
+
+ pRawi += 2;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_GA16, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_rgba8 (mng_datap pData)
+{
+ mng_uint8p pRawi, pRawo;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_RGBA8, MNG_LC_START);
+#endif
+
+ pRawi = pData->pWorkrow + pData->iPixelofs;
+ pRawo = pData->pPrevrow + pData->iPixelofs;
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsamples - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsamples; iX++)
+#endif
+ {
+ *(pRawo+1) = (mng_uint8)(((mng_uint16)*(pRawi+1) + pData->iLevel1) & 0xFF);
+ *pRawo = (mng_uint8)(((mng_uint16)*pRawi + pData->iLevel0 +
+ (mng_uint16)*(pRawo+1)) & 0xFF);
+ *(pRawo+2) = (mng_uint8)(((mng_uint16)*(pRawi+2) + pData->iLevel2 +
+ (mng_uint16)*(pRawo+1)) & 0xFF);
+ *(pRawo+3) = (mng_uint8)(((mng_uint16)*(pRawi+3) + pData->iLevel3) & 0xFF);
+
+ pRawi += 4;
+ pRawo += 4;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_RGBA8, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_differ_rgba16 (mng_datap pData)
+{
+ mng_uint16p pRawi, pRawo;
+ mng_int32 iX;
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_RGBA16, MNG_LC_START);
+#endif
+
+ pRawi = (mng_uint16p)(pData->pWorkrow + pData->iPixelofs);
+ pRawo = (mng_uint16p)(pData->pPrevrow + pData->iPixelofs);
+
+#ifdef MNG_DECREMENT_LOOPS
+ for (iX = pData->iRowsamples - 1; iX >= 0; iX--)
+#else
+ for (iX = 0; iX < pData->iRowsamples; iX++)
+#endif
+ {
+ *(pRawo+1) = (mng_uint16)(((mng_uint32)*(pRawi+1) + (mng_uint32)pData->iLevel1) & 0xFFFF);
+ *pRawo = (mng_uint16)(((mng_uint32)*pRawi + (mng_uint32)pData->iLevel0 +
+ (mng_uint32)*(pRawo+1)) & 0xFFFF);
+ *(pRawo+2) = (mng_uint16)(((mng_uint32)*(pRawi+2) + (mng_uint32)pData->iLevel2 +
+ (mng_uint32)*(pRawo+1)) & 0xFFFF);
+ *(pRawo+3) = (mng_uint16)(((mng_uint32)*(pRawi+3) + (mng_uint32)pData->iLevel3) & 0xFFFF);
+
+ pRawi += 4;
+ pRawo += 4;
+ }
+
+#ifdef MNG_SUPPORT_TRACE
+ MNG_TRACE (pData, MNG_FN_DIFFER_RGBA16, MNG_LC_END);
+#endif
+
+ return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+#endif /* FILTER192 */
+
+/* ************************************************************************** */
+
+#endif /* MNG_INCLUDE_FILTERS */
+
+/* ************************************************************************** */
+/* * end of file * */
+/* ************************************************************************** */
+