C++程序
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/*====================================================================*
- Copyright (C) 2001 Leptonica. All rights reserved.
- This software is distributed in the hope that it will be
- useful, but with NO WARRANTY OF ANY KIND.
- No author or distributor accepts responsibility to anyone for the
- consequences of using this software, or for whether it serves any
- particular purpose or works at all, unless he or she says so in
- writing. Everyone is granted permission to copy, modify and
- redistribute this source code, for commercial or non-commercial
- purposes, with the following restrictions: (1) the origin of this
- source code must not be misrepresented; (2) modified versions must
- be plainly marked as such; and (3) this notice may not be removed
- or altered from any source or modified source distribution.
*====================================================================*/
/*
* pixconv.c
*
* These functions convert between images of different types
* without scaling.
*
* Conversion from 8 bpp grayscale to 1, 2, 4 and 8 bpp
* PIX *pixThreshold8()
*
* Conversion from colormap to full color or grayscale
* PIX *pixRemoveColormap()
*
* Add colormap losslessly (8 to 8)
* l_int32 pixAddGrayColormap8()
* PIX *pixAddMinimalGrayColormap8()
*
* Conversion from RGB color to grayscale
* PIX *pixConvertRGBToLuminance()
* PIX *pixConvertRGBToGray()
* PIX *pixConvertRGBToGrayFast()
* PIX *pixConvertRGBToGrayMinMax()
*
* Conversion from grayscale to colormap
* PIX *pixConvertGrayToColormap() -- 2, 4, 8 bpp
* PIX *pixConvertGrayToColormap8() -- 8 bpp only
*
* Colorizing conversion from grayscale to color
* PIX *pixColorizeGray() -- 8 bpp or cmapped
*
* Conversion from RGB color to colormap
* PIX *pixConvertRGBToColormap()
*
* Quantization for relatively small number of colors in source
* l_int32 pixQuantizeIfFewColors()
*
* Conversion from 16 bpp to 8 bpp
* PIX *pixConvert16To8()
*
* Conversion from grayscale to false color
* PIX *pixConvertGrayToFalseColor()
*
* Unpacking conversion from 1 bpp to 2, 4, 8, 16 and 32 bpp
* PIX *pixUnpackBinary()
* PIX *pixConvert1To16()
* PIX *pixConvert1To32()
*
* Unpacking conversion from 1 bpp to 2 bpp
* PIX *pixConvert1To2Cmap()
* PIX *pixConvert1To2()
*
* Unpacking conversion from 1 bpp to 4 bpp
* PIX *pixConvert1To4Cmap()
* PIX *pixConvert1To4()
*
* Unpacking conversion from 1, 2 and 4 bpp to 8 bpp
* PIX *pixConvert1To8()
* PIX *pixConvert2To8()
* PIX *pixConvert4To8()
*
* Unpacking conversion from 8 bpp to 16 bpp
* PIX *pixConvert8To16()
*
* Top-level conversion to 1 bpp
* PIX *pixConvertTo1()
* PIX *pixConvertTo1BySampling()
*
* Top-level conversion to 8 bpp
* PIX *pixConvertTo8()
* PIX *pixConvertTo8BySampling()
*
* Top-level conversion to 16 bpp
* PIX *pixConvertTo16()
*
* Top-level conversion to 32 bpp (RGB)
* PIX *pixConvertTo32() ***
* PIX *pixConvertTo32BySampling() ***
* PIX *pixConvert8To32() ***
*
* Top-level conversion to 8 or 32 bpp, without colormap
* PIX *pixConvertTo8Or32
*
* Lossless depth conversion (unpacking)
* PIX *pixConvertLossless()
*
* Conversion for printing in PostScript
* PIX *pixConvertForPSWrap()
*
* Colorspace conversion between RGB and HSV
* PIX *pixConvertRGBToHSV()
* PIX *pixConvertHSVToRGB()
* l_int32 convertRGBToHSV()
* l_int32 convertHSVToRGB()
* PIX *pixConvertRGBToHue()
* PIX *pixConvertRGBToSaturation()
* PIX *pixConvertRGBToValue()
*
*
* *** indicates implicit assumption about RGB component ordering
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "allheaders.h"
/* These numbers are ad-hoc, but at least they add up
to 1. Unlike, for example, the weighting factor for
conversion of RGB to luminance, or more specifically
to Y in the YUV colorspace. Those numbers come
from the International Telecommunications Union, via ITU-R
(and formerly ITU CCIR 601). */
static const l_float32 L_RED_WEIGHT = 0.3;
static const l_float32 L_GREEN_WEIGHT = 0.5;
static const l_float32 L_BLUE_WEIGHT = 0.2;
#ifndef NO_CONSOLE_IO
#define DEBUG_CONVERT_TO_COLORMAP 0
#define DEBUG_UNROLLING 0
#endif /* ~NO_CONSOLE_IO */
/*-------------------------------------------------------------*
* Conversion from 8 bpp grayscale to 1, 2 4 and 8 bpp *
*-------------------------------------------------------------*/
/*!
* pixThreshold8()
*
* Input: pix (8 bpp grayscale)
* d (destination depth: 1, 2, 4 or 8)
* nlevels (number of levels to be used for colormap)
* cmapflag (1 if makes colormap; 0 otherwise)
* Return: pixd (thresholded with standard dest thresholds),
* or null on error
*
* Notes:
* (1) This uses, by default, equally spaced "target" values
* that depend on the number of levels, with thresholds
* halfway between. For N levels, with separation (N-1)/255,
* there are N-1 fixed thresholds.
* (2) For 1 bpp destination, the number of levels can only be 2
* and if a cmap is made, black is (0,0,0) and white
* is (255,255,255), which is opposite to the convention
* without a colormap.
* (3) For 1, 2 and 4 bpp, the nlevels arg is used if a colormap
* is made; otherwise, we take the most significant bits
* from the src that will fit in the dest.
* (4) For 8 bpp, the input pixs is quantized to nlevels. The
* dest quantized with that mapping, either through a colormap
* table or directly with 8 bit values.
* (5) Typically you should not use make a colormap for 1 bpp dest.
* (6) This is not dithering. Each pixel is treated independently.
*/
PIX *
pixThreshold8(PIX *pixs,
l_int32 d,
l_int32 nlevels,
l_int32 cmapflag)
{
PIX *pixd;
PIXCMAP *cmap;
PROCNAME("pixThreshold8");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 8)
return (PIX *)ERROR_PTR("pixs not 8 bpp", procName, NULL);
if (cmapflag && nlevels < 2)
return (PIX *)ERROR_PTR("nlevels must be at least 2", procName, NULL);
switch (d) {
case 1:
pixd = pixThresholdToBinary(pixs, 128);
if (cmapflag) {
cmap = pixcmapCreateLinear(1, 2);
pixSetColormap(pixd, cmap);
}
break;
case 2:
pixd = pixThresholdTo2bpp(pixs, nlevels, cmapflag);
break;
case 4:
pixd = pixThresholdTo4bpp(pixs, nlevels, cmapflag);
break;
case 8:
pixd = pixThresholdOn8bpp(pixs, nlevels, cmapflag);
break;
default:
return (PIX *)ERROR_PTR("d must be in {1,2,4,8}", procName, NULL);
}
if (!pixd)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
return pixd;
}
/*-------------------------------------------------------------*
* Conversion from colormapped pix *
*-------------------------------------------------------------*/
/*!
* pixRemoveColormap()
*
* Input: pixs (see restrictions below)
* type (REMOVE_CMAP_TO_BINARY,
* REMOVE_CMAP_TO_GRAYSCALE,
* REMOVE_CMAP_TO_FULL_COLOR,
* REMOVE_CMAP_BASED_ON_SRC)
* Return: new pix, or null on error
*
* Notes:
* (1) If there is no colormap, a clone is returned.
* (2) Otherwise, the input pixs is restricted to 1, 2, 4 or 8 bpp.
* (3) Use REMOVE_CMAP_TO_BINARY only on 1 bpp pix.
* (4) For grayscale conversion from RGB, use a weighted average
* of RGB values, and always return an 8 bpp pix, regardless
* of whether the input pixs depth is 2, 4 or 8 bpp.
*/
PIX *
pixRemoveColormap(PIX *pixs,
l_int32 type)
{
l_int32 sval, rval, gval, bval;
l_int32 i, j, k, w, h, d, wpls, wpld, ncolors, count;
l_int32 colorfound;
l_int32 *rmap, *gmap, *bmap, *graymap;
l_uint32 *datas, *lines, *datad, *lined, *lut;
l_uint32 sword, dword;
PIXCMAP *cmap;
PIX *pixd;
PROCNAME("pixRemoveColormap");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if ((cmap = pixGetColormap(pixs)) == NULL)
return pixClone(pixs);
if (type != REMOVE_CMAP_TO_BINARY &&
type != REMOVE_CMAP_TO_GRAYSCALE &&
type != REMOVE_CMAP_TO_FULL_COLOR &&
type != REMOVE_CMAP_BASED_ON_SRC) {
L_WARNING("Invalid type; converting based on src", procName);
type = REMOVE_CMAP_BASED_ON_SRC;
}
pixGetDimensions(pixs, &w, &h, &d);
if (d != 1 && d != 2 && d != 4 && d != 8)
return (PIX *)ERROR_PTR("pixs must be {1,2,4,8} bpp", procName, NULL);
if (pixcmapToArrays(cmap, &rmap, &gmap, &bmap))
return (PIX *)ERROR_PTR("colormap arrays not made", procName, NULL);
if (d != 1 && type == REMOVE_CMAP_TO_BINARY) {
L_WARNING("not 1 bpp; can't remove cmap to binary", procName);
type = REMOVE_CMAP_BASED_ON_SRC;
}
if (type == REMOVE_CMAP_BASED_ON_SRC) {
/* select output type depending on colormap */
pixcmapHasColor(cmap, &colorfound);
if (!colorfound) {
if (d == 1)
type = REMOVE_CMAP_TO_BINARY;
else
type = REMOVE_CMAP_TO_GRAYSCALE;
}
else
type = REMOVE_CMAP_TO_FULL_COLOR;
}
ncolors = pixcmapGetCount(cmap);
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
if (type == REMOVE_CMAP_TO_BINARY) {
if ((pixd = pixCopy(NULL, pixs)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
pixcmapGetColor(cmap, 0, &rval, &gval, &bval);
if (rval == 0) /* photometrically inverted from standard */
pixInvert(pixd, pixd);
pixDestroyColormap(pixd);
}
else if (type == REMOVE_CMAP_TO_GRAYSCALE) {
if ((pixd = pixCreate(w, h, 8)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
pixCopyResolution(pixd, pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
if ((graymap = (l_int32 *)CALLOC(ncolors, sizeof(l_int32))) == NULL)
return (PIX *)ERROR_PTR("calloc fail for graymap", procName, NULL);
for (i = 0; i < pixcmapGetCount(cmap); i++) {
graymap[i] = (rmap[i] + 2 * gmap[i] + bmap[i]) / 4;
}
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
switch (d) /* depth test above; no default permitted */
{
case 8:
/* Unrolled 4x */
for (j = 0, count = 0; j + 3 < w; j += 4, count++) {
sword = lines[count];
dword = (graymap[(sword >> 24) & 0xff] << 24) |
(graymap[(sword >> 16) & 0xff] << 16) |
(graymap[(sword >> 8) & 0xff] << 8) |
graymap[sword & 0xff];
lined[count] = dword;
}
/* Cleanup partial word */
for (; j < w; j++) {
sval = GET_DATA_BYTE(lines, j);
gval = graymap[sval];
SET_DATA_BYTE(lined, j, gval);
}
#if DEBUG_UNROLLING
#define CHECK_VALUE(a, b, c) if (GET_DATA_BYTE(a, b) != c) { \
fprintf(stderr, "Error: mismatch at %d, %d vs %d\n", \
j, GET_DATA_BYTE(a, b), c); }
for (j = 0; j < w; j++) {
sval = GET_DATA_BYTE(lines, j);
gval = graymap[sval];
CHECK_VALUE(lined, j, gval);
}
#endif
break;
case 4:
/* Unrolled 8x */
for (j = 0, count = 0; j + 7 < w; j += 8, count++) {
sword = lines[count];
dword = (graymap[(sword >> 28) & 0xf] << 24) |
(graymap[(sword >> 24) & 0xf] << 16) |
(graymap[(sword >> 20) & 0xf] << 8) |
graymap[(sword >> 16) & 0xf];
lined[2 * count] = dword;
dword = (graymap[(sword >> 12) & 0xf] << 24) |
(graymap[(sword >> 8) & 0xf] << 16) |
(graymap[(sword >> 4) & 0xf] << 8) |
graymap[sword & 0xf];
lined[2 * count + 1] = dword;
}
/* Cleanup partial word */
for (; j < w; j++) {
sval = GET_DATA_QBIT(lines, j);
gval = graymap[sval];
SET_DATA_BYTE(lined, j, gval);
}
#if DEBUG_UNROLLING
for (j = 0; j < w; j++) {
sval = GET_DATA_QBIT(lines, j);
gval = graymap[sval];
CHECK_VALUE(lined, j, gval);
}
#endif
break;
case 2:
/* Unrolled 16x */
for (j = 0, count = 0; j + 15 < w; j += 16, count++) {
sword = lines[count];
dword = (graymap[(sword >> 30) & 0x3] << 24) |
(graymap[(sword >> 28) & 0x3] << 16) |
(graymap[(sword >> 26) & 0x3] << 8) |
graymap[(sword >> 24) & 0x3];
lined[4 * count] = dword;
dword = (graymap[(sword >> 22) & 0x3] << 24) |
(graymap[(sword >> 20) & 0x3] << 16) |
(graymap[(sword >> 18) & 0x3] << 8) |
graymap[(sword >> 16) & 0x3];
lined[4 * count + 1] = dword;
dword = (graymap[(sword >> 14) & 0x3] << 24) |
(graymap[(sword >> 12) & 0x3] << 16) |
(graymap[(sword >> 10) & 0x3] << 8) |
graymap[(sword >> 8) & 0x3];
lined[4 * count + 2] = dword;
dword = (graymap[(sword >> 6) & 0x3] << 24) |
(graymap[(sword >> 4) & 0x3] << 16) |
(graymap[(sword >> 2) & 0x3] << 8) |
graymap[sword & 0x3];
lined[4 * count + 3] = dword;
}
/* Cleanup partial word */
for (; j < w; j++) {
sval = GET_DATA_DIBIT(lines, j);
gval = graymap[sval];
SET_DATA_BYTE(lined, j, gval);
}
#if DEBUG_UNROLLING
for (j = 0; j < w; j++) {
sval = GET_DATA_DIBIT(lines, j);
gval = graymap[sval];
CHECK_VALUE(lined, j, gval);
}
#endif
break;
case 1:
/* Unrolled 8x */
for (j = 0, count = 0; j + 31 < w; j += 32, count++) {
sword = lines[count];
for (k = 0; k < 4; k++) {
/* The top byte is always the relevant one */
dword = (graymap[(sword >> 31) & 0x1] << 24) |
(graymap[(sword >> 30) & 0x1] << 16) |
(graymap[(sword >> 29) & 0x1] << 8) |
graymap[(sword >> 28) & 0x1];
lined[8 * count + 2 * k] = dword;
dword = (graymap[(sword >> 27) & 0x1] << 24) |
(graymap[(sword >> 26) & 0x1] << 16) |
(graymap[(sword >> 25) & 0x1] << 8) |
graymap[(sword >> 24) & 0x1];
lined[8 * count + 2 * k + 1] = dword;
sword <<= 8; /* Move up the next byte */
}
}
/* Cleanup partial word */
for (; j < w; j++) {
sval = GET_DATA_BIT(lines, j);
gval = graymap[sval];
SET_DATA_BYTE(lined, j, gval);
}
#if DEBUG_UNROLLING
for (j = 0; j < w; j++) {
sval = GET_DATA_BIT(lines, j);
gval = graymap[sval];
CHECK_VALUE(lined, j, gval);
}
#undef CHECK_VALUE
#endif
break;
default:
return NULL;
}
}
if (graymap)
FREE(graymap);
}
else { /* type == REMOVE_CMAP_TO_FULL_COLOR */
if ((pixd = pixCreate(w, h, 32)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
pixCopyResolution(pixd, pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
if ((lut = (l_uint32 *)CALLOC(ncolors, sizeof(l_uint32))) == NULL)
return (PIX *)ERROR_PTR("calloc fail for lut", procName, NULL);
for (i = 0; i < ncolors; i++)
composeRGBPixel(rmap[i], gmap[i], bmap[i], lut + i);
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
if (d == 8)
sval = GET_DATA_BYTE(lines, j);
else if (d == 4)
sval = GET_DATA_QBIT(lines, j);
else if (d == 2)
sval = GET_DATA_DIBIT(lines, j);
else if (d == 1)
sval = GET_DATA_BIT(lines, j);
else
return NULL;
if (sval >= ncolors)
L_WARNING("pixel value out of bounds", procName);
else
lined[j] = lut[sval];
}
}
FREE(lut);
}
FREE(rmap);
FREE(gmap);
FREE(bmap);
return pixd;
}
/*-------------------------------------------------------------*
* Add colormap losslessly (8 to 8) *
*-------------------------------------------------------------*/
/*!
* pixAddGrayColormap8()
*
* Input: pixs (8 bpp)
* Return: 0 if OK, 1 on error
*
* Notes:
* (1) If pixs has a colormap, this is a no-op.
*/
l_int32
pixAddGrayColormap8(PIX *pixs)
{
PIXCMAP *cmap;
PROCNAME("pixAddGrayColormap8");
if (!pixs || pixGetDepth(pixs) != 8)
return ERROR_INT("pixs not defined or not 8 bpp", procName, 1);
if (pixGetColormap(pixs))
return 0;
cmap = pixcmapCreateLinear(8, 256);
pixSetColormap(pixs, cmap);
return 0;
}
/*!
* pixAddMinimalGrayColormap8()
*
* Input: pixs (8 bpp)
* Return: 0 if OK, 1 on error
*
* Notes:
* (1) This generates a colormapped version of the input image
* that has the same number of colormap entries as the
* input image has unique gray levels.
*/
PIX *
pixAddMinimalGrayColormap8(PIX *pixs)
{
l_int32 ncolors, w, h, i, j, wplt, wpld, index, val;
l_int32 *inta, *revmap;
l_uint32 *datat, *datad, *linet, *lined;
PIX *pixt, *pixd;
PIXCMAP *cmap;
PROCNAME("pixAddMinimalGrayColormap8");
if (!pixs || pixGetDepth(pixs) != 8)
return (PIX *)ERROR_PTR("pixs undefined or not 8 bpp", procName, NULL);
/* Eliminate the easy cases */
pixNumColors(pixs, 1, &ncolors);
cmap = pixGetColormap(pixs);
if (cmap) {
if (pixcmapGetCount(cmap) == ncolors) /* irreducible */
return pixCopy(NULL, pixs);
else
pixt = pixRemoveColormap(pixs, REMOVE_CMAP_TO_GRAYSCALE);
}
else {
if (ncolors == 256) {
pixt = pixCopy(NULL, pixs);
pixAddGrayColormap8(pixt);
return pixt;
}
pixt = pixClone(pixs);
}
/* Find the gray levels and make a reverse map */
pixGetDimensions(pixt, &w, &h, NULL);
datat = pixGetData(pixt);
wplt = pixGetWpl(pixt);
inta = (l_int32 *)CALLOC(256, sizeof(l_int32));
for (i = 0; i < h; i++) {
linet = datat + i * wplt;
for (j = 0; j < w; j++) {
val = GET_DATA_BYTE(linet, j);
inta[val] = 1;
}
}
cmap = pixcmapCreate(8);
revmap = (l_int32 *)CALLOC(256, sizeof(l_int32));
for (i = 0, index = 0; i < 256; i++) {
if (inta[i]) {
pixcmapAddColor(cmap, i, i, i);
revmap[i] = index++;
}
}
/* Set all pixels in pixd to the colormap index */
pixd = pixCreateTemplate(pixt);
pixSetColormap(pixd, cmap);
pixCopyResolution(pixd, pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
for (i = 0; i < h; i++) {
linet = datat + i * wplt;
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
val = GET_DATA_BYTE(linet, j);
SET_DATA_BYTE(lined, j, revmap[val]);
}
}
pixDestroy(&pixt);
FREE(inta);
FREE(revmap);
return pixd;
}
/*-------------------------------------------------------------*
* Conversion from RGB color to grayscale *
*-------------------------------------------------------------*/
/*!
* pixConvertRGBToLuminance()
*
* Input: pix (32 bpp RGB)
* Return: 8 bpp pix, or null on error
*
* Notes:
* (1) Use a standard luminance conversion.
*/
PIX *
pixConvertRGBToLuminance(PIX *pixs)
{
return pixConvertRGBToGray(pixs, 0.0, 0.0, 0.0);
}
/*!
* pixConvertRGBToGray()
*
* Input: pix (32 bpp RGB)
* rwt, gwt, bwt (non-negative; these should add to 1.0,
* or use 0.0 for default)
* Return: 8 bpp pix, or null on error
*
* Notes:
* (1) Use a weighted average of the RGB values.
*/
PIX *
pixConvertRGBToGray(PIX *pixs,
l_float32 rwt,
l_float32 gwt,
l_float32 bwt)
{
l_int32 i, j, w, h, wpls, wpld, rval, gval, bval, val;
l_uint32 *datas, *lines, *datad, *lined;
l_float32 sum;
PIX *pixd;
PROCNAME("pixConvertRGBToGray");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 32)
return (PIX *)ERROR_PTR("pixs not 32 bpp", procName, NULL);
if (rwt < 0.0 || gwt < 0.0 || bwt < 0.0)
return (PIX *)ERROR_PTR("weights not all >= 0.0", procName, NULL);
/* Make sure the sum of weights is 1.0; otherwise, you can get
* overflow in the gray value. */
if (rwt == 0.0 && gwt == 0.0 && bwt == 0.0) {
rwt = L_RED_WEIGHT;
gwt = L_GREEN_WEIGHT;
bwt = L_BLUE_WEIGHT;
}
sum = rwt + gwt + bwt;
if (L_ABS(sum - 1.0) > 0.0001) { /* maintain ratios with sum == 1.0 */
L_WARNING("weights don't sum to 1; maintaining ratios", procName);
rwt = rwt / sum;
gwt = gwt / sum;
bwt = bwt / sum;
}
pixGetDimensions(pixs, &w, &h, NULL);
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
if ((pixd = pixCreate(w, h, 8)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
pixCopyResolution(pixd, pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
extractRGBValues(lines[j], &rval, &gval, &bval);
val = (l_int32)(rwt * rval + gwt * gval + bwt * bval + 0.5);
SET_DATA_BYTE(lined, j, val);
}
}
return pixd;
}
/*!
* pixConvertRGBToGrayFast()
*
* Input: pix (32 bpp RGB)
* Return: 8 bpp pix, or null on error
*
* Notes:
* (1) This function should be used if speed of conversion
* is paramount, and the green channel can be used as
* a fair representative of the RGB intensity. It is
* several times faster than pixConvertRGBToGray().
* (2) To combine RGB to gray conversion with subsampling,
* use pixScaleRGBToGrayFast() instead.
*/
PIX *
pixConvertRGBToGrayFast(PIX *pixs)
{
l_int32 i, j, w, h, wpls, wpld, val;
l_uint32 *datas, *lines, *datad, *lined;
PIX *pixd;
PROCNAME("pixConvertRGBToGrayFast");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 32)
return (PIX *)ERROR_PTR("pixs not 32 bpp", procName, NULL);
pixGetDimensions(pixs, &w, &h, NULL);
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
if ((pixd = pixCreate(w, h, 8)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
pixCopyResolution(pixd, pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < w; j++, lines++) {
val = ((*lines) >> L_GREEN_SHIFT) & 0xff;
SET_DATA_BYTE(lined, j, val);
}
}
return pixd;
}
/*!
* pixConvertRGBToGrayMinMax()
*
* Input: pix (32 bpp RGB)
* type (L_CHOOSE_MIN or L_CHOOSE_MAX)
* Return: 8 bpp pix, or null on error
*
* Notes:
* (1) @type chooses among the 3 color components for each pixel
* (2) This is useful when looking for the maximum deviation
* of a component from either 0 or 255. For finding the
* deviation of a single component, it is more sensitive
* than using a weighted average.
*/
PIX *
pixConvertRGBToGrayMinMax(PIX *pixs,
l_int32 type)
{
l_int32 i, j, w, h, wpls, wpld, rval, gval, bval, val;
l_uint32 *datas, *lines, *datad, *lined;
PIX *pixd;
PROCNAME("pixConvertRGBToGrayMinMax");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 32)
return (PIX *)ERROR_PTR("pixs not 32 bpp", procName, NULL);
if (type != L_CHOOSE_MIN && type != L_CHOOSE_MAX)
return (PIX *)ERROR_PTR("invalid type", procName, NULL);
pixGetDimensions(pixs, &w, &h, NULL);
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
if ((pixd = pixCreate(w, h, 8)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
pixCopyResolution(pixd, pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
extractRGBValues(lines[j], &rval, &gval, &bval);
if (type == L_CHOOSE_MIN) {
val = L_MIN(rval, gval);
val = L_MIN(val, bval);
}
else { /* type == L_CHOOSE_MAX */
val = L_MAX(rval, gval);
val = L_MAX(val, bval);
}
SET_DATA_BYTE(lined, j, val);
}
}
return pixd;
}
/*---------------------------------------------------------------------------*
* Conversion from grayscale to colormap *
*---------------------------------------------------------------------------*/
/*!
* pixConvertGrayToColormap()
*
* Input: pixs (2, 4 or 8 bpp grayscale)
* Return: pixd (2, 4 or 8 bpp with colormap), or null on error
*
* Notes:
* (1) This is a simple interface for adding a colormap to a
* 2, 4 or 8 bpp grayscale image without causing any
* quantization. There is some similarity to operations
* in grayquant.c, such as pixThresholdOn8bpp(), where
* the emphasis is on quantization with an arbitrary number
* of levels, and a colormap is an option.
* (2) Returns a copy if pixs already has a colormap.
* (3) For 8 bpp src, this is a lossless transformation.
* (4) For 2 and 4 bpp src, this generates a colormap that
* assumes full coverage of the gray space, with equally spaced
* levels: 4 levels for d = 2 and 16 levels for d = 4.
* (5) In all cases, the depth of the dest is the same as the src.
*/
PIX *
pixConvertGrayToColormap(PIX *pixs)
{
l_int32 d;
PIX *pixd;
PIXCMAP *cmap;
PROCNAME("pixConvertGrayToColormap");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
d = pixGetDepth(pixs);
if (d != 2 && d != 4 && d != 8)
return (PIX *)ERROR_PTR("pixs not 2, 4 or 8 bpp", procName, NULL);
if (pixGetColormap(pixs)) {
L_WARNING("pixs already has a colormap", procName);
return pixCopy(NULL, pixs);
}
if (d == 8) /* lossless conversion */
return pixConvertGrayToColormap8(pixs, 2);
/* Build a cmap with equally spaced target values over the
* full 8 bpp range. */
pixd = pixCopy(NULL, pixs);
cmap = pixcmapCreateLinear(d, 1 << d);
pixSetColormap(pixd, cmap);
return pixd;
}
/*!
* pixConvertGrayToColormap8()
*
* Input: pixs (8 bpp grayscale)
* mindepth (of pixd; valid values are 2, 4 and 8)
* Return: pixd (2, 4 or 8 bpp with colormap), or null on error
*
* Notes:
* (1) Returns a copy if pixs already has a colormap.
* (2) This is a lossless transformation; there is no quantization.
* We compute the number of different gray values in pixs,
* and construct a colormap that has exactly these values.
* (3) 'mindepth' is the minimum depth of pixd. If mindepth == 8,
* pixd will always be 8 bpp. Let the number of different
* gray values in pixs be ngray. If mindepth == 4, we attempt
* to save pixd as a 4 bpp image, but if ngray > 16,
* pixd must be 8 bpp. Likewise, if mindepth == 2,
* the depth of pixd will be 2 if ngray <= 4 and 4 if ngray > 4
* but <= 16.
*/
PIX *
pixConvertGrayToColormap8(PIX *pixs,
l_int32 mindepth)
{
l_int32 ncolors, w, h, depth, i, j, wpls, wpld;
l_int32 index, num, val, newval;
l_int32 array[256];
l_uint32 *lines, *lined, *datas, *datad;
NUMA *na;
PIX *pixd;
PIXCMAP *cmap;
PROCNAME("pixConvertGrayToColormap8");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 8)
return (PIX *)ERROR_PTR("pixs not 8 bpp", procName, NULL);
if (mindepth != 2 && mindepth != 4 && mindepth != 8) {
L_WARNING("invalid value of mindepth; setting to 8", procName);
mindepth = 8;
}
if (pixGetColormap(pixs)) {
L_WARNING("pixs already has a colormap", procName);
return pixCopy(NULL, pixs);
}
na = pixGetGrayHistogram(pixs, 1);
numaGetCountRelativeToZero(na, L_GREATER_THAN_ZERO, &ncolors);
if (mindepth == 8 || ncolors > 16)
depth = 8;
else if (mindepth == 4 || ncolors > 4)
depth = 4;
else
depth = 2;
pixGetDimensions(pixs, &w, &h, NULL);
pixd = pixCreate(w, h, depth);
cmap = pixcmapCreate(depth);
pixSetColormap(pixd, cmap);
pixCopyResolution(pixd, pixs);
index = 0;
for (i = 0; i < 256; i++) {
numaGetIValue(na, i, &num);
if (num > 0) {
pixcmapAddColor(cmap, i, i, i);
array[i] = index;
index++;
}
}
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
val = GET_DATA_BYTE(lines, j);
newval = array[val];
if (depth == 2)
SET_DATA_DIBIT(lined, j, newval);
else if (depth == 4)
SET_DATA_QBIT(lined, j, newval);
else /* depth == 8 */
SET_DATA_BYTE(lined, j, newval);
}
}
numaDestroy(&na);
return pixd;
}
/*---------------------------------------------------------------------------*
* Colorizing conversion from grayscale to color *
*---------------------------------------------------------------------------*/
/*!
* pixColorizeGray()
*
* Input: pixs (8 bpp gray; 2, 4 or 8 bpp colormapped)
* color (32 bit rgba pixel)
* cmapflag (1 for result to have colormap; 0 for RGB)
* Return: pixd (8 bpp colormapped or 32 bpp rgb), or null on error
*
* Notes:
* (1) This applies the specific color to the grayscale image.
* (2) If pixs already has a colormap, it is removed to gray
* before colorizing.
*/
PIX *
pixColorizeGray(PIX *pixs,
l_uint32 color,
l_int32 cmapflag)
{
l_int32 i, j, w, h, wplt, wpld, val8;
l_uint32 *datad, *datat, *lined, *linet, *tab;
PIX *pixt, *pixd;
PIXCMAP *cmap;
PROCNAME("pixColorizeGray");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 8 && !pixGetColormap(pixs))
return (PIX *)ERROR_PTR("pixs not 8 bpp or cmapped", procName, NULL);
if (pixGetColormap(pixs))
pixt = pixRemoveColormap(pixs, REMOVE_CMAP_TO_GRAYSCALE);
else
pixt = pixClone(pixs);
cmap = pixcmapGrayToColor(color);
if (cmapflag) {
pixd = pixCopy(NULL, pixt);
pixSetColormap(pixd, cmap);
pixDestroy(&pixt);
return pixd;
}
/* Make an RGB pix */
pixcmapToRGBTable(cmap, &tab, NULL);
pixGetDimensions(pixt, &w, &h, NULL);
pixd = pixCreate(w, h, 32);
pixCopyResolution(pixd, pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
datat = pixGetData(pixt);
wplt = pixGetWpl(pixt);
for (i = 0; i < h; i++) {
lined = datad + i * wpld;
linet = datat + i * wplt;
for (j = 0; j < w; j++) {
val8 = GET_DATA_BYTE(linet, j);
lined[j] = tab[val8];
}
}
pixDestroy(&pixt);
pixcmapDestroy(&cmap);
FREE(tab);
return pixd;
}
/*---------------------------------------------------------------------------*
* Conversion from RGB color to colormap *
*---------------------------------------------------------------------------*/
/*!
* pixConvertRGBToColormap()
*
* Input: pixs (32 bpp rgb)
* ditherflag (1 to dither, 0 otherwise)
* Return: pixd (2, 4 or 8 bpp with colormap), or null on error
*
* Notes:
* (1) This function has two relatively simple modes of color
* quantization:
* (a) If the image is made orthographically and has not more
* than 256 'colors' at the level 4 octcube leaves,
* it is quantized nearly exactly. The ditherflag
* is ignored.
* (b) Most natural images have more than 256 different colors;
* in that case we use adaptive octree quantization,
* with dithering if requested.
* (2) If there are not more than 256 occupied level 4 octcubes,
* the color in the colormap that represents all pixels in
* one of those octcubes is given by the first pixel that
* falls into that octcube.
* (3) If there are more than 256 colors, we use adaptive octree
* color quantization.
* (4) Dithering gives better visual results on images where
* there is a color wash (a slow variation of color), but it
* is about twice as slow and results in significantly larger
* files when losslessly compressed (e.g., into png).
*/
PIX *
pixConvertRGBToColormap(PIX *pixs,
l_int32 ditherflag)
{
l_int32 ncolors;
NUMA *na;
PIX *pixd;
PROCNAME("pixConvertRGBToColormap");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 32)
return (PIX *)ERROR_PTR("pixs not 32 bpp", procName, NULL);
/* Get the histogram and count the number of occupied level 4
* leaf octcubes. We don't yet know if this is the number of
* actual colors, but if it's not, all pixels falling into
* the same leaf octcube will be assigned to the color of the
* first pixel that lands there. */
na = pixOctcubeHistogram(pixs, 4, &ncolors);
/* If there are too many occupied leaf octcubes to be
* represented directly in a colormap, fall back to octree
* quantization with dithering. */
if (ncolors > 256) {
L_INFO("More than 256 colors; using octree quant with dithering",
procName);
numaDestroy(&na);
return pixOctreeColorQuant(pixs, 240, ditherflag);
}
/* There are not more than 256 occupied leaf octcubes.
* Quantize to those octcubes. */
pixd = pixFewColorsOctcubeQuant2(pixs, 4, na, ncolors, NULL);
numaDestroy(&na);
return pixd;
}
/*---------------------------------------------------------------------------*
* Quantization for relatively small number of colors in source *
*---------------------------------------------------------------------------*/
/*!
* pixQuantizeIfFewColors()
*
* Input: pixs (8 bpp gray or 32 bpp rgb)
* maxcolors (max number of colors allowed to be returned
* from pixColorsForQuantization(); use 0 for default)
* mingraycolors (min number of gray levels that a grayscale
* image is quantized to; use 0 for default)
* octlevel (for octcube quantization: 3 or 4)
* &pixd (2, 4 or 8 bpp quantized; null if too many colors)
* Return: 0 if OK, 1 on error or if pixs can't be quantized into
* a small number of colors.
*
* Notes:
* (1) This is a wrapper that tests if the pix can be quantized
* with good quality using a small number of colors. If so,
* it does the quantization, defining a colormap and using
* pixels whose value is an index into the colormap.
* (2) If the image has color, it is quantized with 8 bpp pixels.
* If the image is essentially grayscale, the pixels are
* either 4 or 8 bpp, depending on the size of the required
* colormap.
* (3) @octlevel = 3 works well for most images. However, for best
* quality, at a cost of more colors in the colormap, use
* @octlevel = 4.
* (4) If the image already has a colormap, it returns a clone.
*/
l_int32
pixQuantizeIfFewColors(PIX *pixs,
l_int32 maxcolors,
l_int32 mingraycolors,
l_int32 octlevel,
PIX **ppixd)
{
l_int32 d, ncolors, iscolor, graycolors;
PIX *pixg, *pixd;
PROCNAME("pixQuantizeIfFewColors");
if (!ppixd)
return ERROR_INT("&pixd not defined", procName, 1);
*ppixd = NULL;
if (!pixs)
return ERROR_INT("pixs not defined", procName, 1);
d = pixGetDepth(pixs);
if (d != 8 && d != 32)
return ERROR_INT("pixs not defined", procName, 1);
if (pixGetColormap(pixs) != NULL) {
*ppixd = pixClone(pixs);
return 0;
}
if (maxcolors <= 0)
maxcolors = 15; /* default */
if (maxcolors > 50)
L_WARNING("maxcolors > 50; very large!", procName);
if (mingraycolors <= 0)
mingraycolors = 10; /* default */
if (mingraycolors > 30)
L_WARNING("mingraycolors > 30; very large!", procName);
if (octlevel != 3 && octlevel != 4) {
L_WARNING("invalid octlevel; setting to 3", procName);
octlevel = 3;
}
/* Test the number of colors. For color, the octcube leaves
* are at level 4. */
pixColorsForQuantization(pixs, 0, &ncolors, &iscolor, 0);
if (ncolors > maxcolors)
return ERROR_INT("too many colors", procName, 1);
/* Quantize!
* (1) For color:
* If octlevel == 4, try to quantize to an octree where
* the octcube leaves are at level 4. If that fails,
* back off to level 3.
* If octlevel == 3, quantize to level 3 directly.
* For level 3, the quality is usually good enough and there
* is negligible chance of getting more than 256 colors.
* (2) For grayscale, multiply ncolors by 1.5 for extra quality,
* but use at least mingraycolors. */
if (iscolor) {
pixd = pixFewColorsOctcubeQuant1(pixs, octlevel);
if (!pixd) { /* backoff */
pixd = pixFewColorsOctcubeQuant1(pixs, octlevel - 1);
if (octlevel == 3) /* shouldn't happen */
L_WARNING("quantized at level 2; low quality", procName);
}
}
else { /* image is really grayscale */
if (d == 32)
pixg = pixConvertRGBToLuminance(pixs);
else
pixg = pixClone(pixs);
graycolors = L_MAX(mingraycolors, (l_int32)(1.5 * ncolors));
if (graycolors < 16)
pixd = pixThresholdTo4bpp(pixg, graycolors, 1);
else
pixd = pixThresholdOn8bpp(pixg, graycolors, 1);
pixDestroy(&pixg);
}
*ppixd = pixd;
if (!pixd)
return ERROR_INT("pixd not made", procName, 1);
else
return 0;
}
/*---------------------------------------------------------------------------*
* Conversion from 16 bpp to 8 bpp *
*---------------------------------------------------------------------------*/
/*!
* pixConvert16To8()
*
* Input: pixs (16 bpp)
* whichbyte (1 for MSB, 0 for LSB)
* Return: pixd (8 bpp), or null on error
*
* Notes:
* (1) For each dest pixel, use either the MSB or LSB of each src pixel.
*/
PIX *
pixConvert16To8(PIX *pixs,
l_int32 whichbyte)
{
l_uint16 dsword;
l_int32 w, h, wpls, wpld, i, j;
l_uint32 sword;
l_uint32 *datas, *datad, *lines, *lined;
PIX *pixd;
PROCNAME("pixConvert16To8");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 16)
return (PIX *)ERROR_PTR("pixs not 16 bpp", procName, NULL);
pixGetDimensions(pixs, &w, &h, NULL);
if ((pixd = pixCreate(w, h, 8)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
pixCopyResolution(pixd, pixs);
wpls = pixGetWpl(pixs);
datas = pixGetData(pixs);
wpld = pixGetWpl(pixd);
datad = pixGetData(pixd);
/* Convert 2 pixels at a time */
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
if (whichbyte == 0) { /* LSB */
for (j = 0; j < wpls; j++) {
sword = *(lines + j);
dsword = ((sword >> 8) & 0xff00) | (sword & 0xff);
SET_DATA_TWO_BYTES(lined, j, dsword);
}
}
else { /* MSB */
for (j = 0; j < wpls; j++) {
sword = *(lines + j);
dsword = ((sword >> 16) & 0xff00) | ((sword >> 8) & 0xff);
SET_DATA_TWO_BYTES(lined, j, dsword);
}
}
}
return pixd;
}
/*---------------------------------------------------------------------------*
* Conversion from grayscale to false color
*---------------------------------------------------------------------------*/
/*!
* pixConvertGrayToFalseColor()
*
* Input: pixs (8 or 16 bpp grayscale)
* gamma factor (0.0 or 1.0 for default; > 1.0 for brighter;
* 2.0 is quite nice)
* Return: pixd (8 bpp with colormap), or null on error
*
* Notes:
* (1) For 8 bpp input, this simply adds a colormap to the input image.
* (2) For 16 bpp input, it first converts to 8 bpp and then
* adds the colormap.
* (3) The colormap is modeled after the Matlab "jet" configuration.
*/
PIX *
pixConvertGrayToFalseColor(PIX *pixs,
l_float32 gamma)
{
l_int32 d, i, rval, bval, gval;
l_int32 *curve;
l_float32 invgamma, x;
PIX *pixd;
PIXCMAP *cmap;
PROCNAME("pixConvertGrayToFalseColor");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
d = pixGetDepth(pixs);
if (d != 8 && d != 16)
return (PIX *)ERROR_PTR("pixs not 8 or 16 bpp", procName, NULL);
if (d == 16)
pixd = pixConvert16To8(pixs, 1);
else { /* d == 8 */
if (pixGetColormap(pixs))
pixd = pixRemoveColormap(pixs, REMOVE_CMAP_TO_GRAYSCALE);
else
pixd = pixCopy(NULL, pixs);
}
if (!pixd)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
if ((cmap = pixcmapCreate(8)) == NULL)
return (PIX *)ERROR_PTR("cmap not made", procName, NULL);
pixSetColormap(pixd, cmap);
pixCopyResolution(pixd, pixs);
/* Generate curve for transition part of color map */
if ((curve = (l_int32 *)CALLOC(64, sizeof(l_int32)))== NULL)
return (PIX *)ERROR_PTR("curve not made", procName, NULL);
if (gamma == 0.0) gamma = 1.0;
invgamma = 1. / gamma;
for (i = 0; i < 64; i++) {
x = (l_float32)i / 64.;
curve[i] = (l_int32)(255. * powf(x, invgamma) + 0.5);
}
for (i = 0; i < 256; i++) {
if (i < 32) {
rval = 0;
gval = 0;
bval = curve[i + 32];
}
else if (i < 96) { /* 32 - 95 */
rval = 0;
gval = curve[i - 32];
bval = 255;
}
else if (i < 160) { /* 96 - 159 */
rval = curve[i - 96];
gval = 255;
bval = curve[159 - i];
}
else if (i < 224) { /* 160 - 223 */
rval = 255;
gval = curve[223 - i];
bval = 0;
}
else { /* 224 - 255 */
rval = curve[287 - i];
gval = 0;
bval = 0;
}
pixcmapAddColor(cmap, rval, gval, bval);
}
FREE(curve);
return pixd;
}
/*---------------------------------------------------------------------------*
* Unpacking conversion from 1 bpp to 2, 4, 8, 16 and 32 bpp *
*---------------------------------------------------------------------------*/
/*!
* pixUnpackBinary()
*
* Input: pixs (1 bpp)
* depth (of destination: 2, 4, 8, 16 or 32 bpp)
* invert (0: binary 0 --> grayscale 0
* binary 1 --> grayscale 0xff...
* 1: binary 0 --> grayscale 0xff...
* binary 1 --> grayscale 0)
* Return: pixd (2, 4, 8, 16 or 32 bpp), or null on error
*
* Notes:
* (1) This function calls special cases of pixConvert1To*(),
* for 2, 4, 8, 16 and 32 bpp destinations.
*/
PIX *
pixUnpackBinary(PIX *pixs,
l_int32 depth,
l_int32 invert)
{
PIX *pixd;
PROCNAME("pixUnpackBinary");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 1)
return (PIX *)ERROR_PTR("pixs not 1 bpp", procName, NULL);
if (depth != 2 && depth != 4 && depth != 8 && depth != 16 && depth != 32)
return (PIX *)ERROR_PTR("depth not 2, 4, 8, 16 or 32 bpp",
procName, NULL);
if (depth == 2) {
if (invert == 0)
pixd = pixConvert1To2(NULL, pixs, 0, 3);
else /* invert bits */
pixd = pixConvert1To2(NULL, pixs, 3, 0);
}
else if (depth == 4) {
if (invert == 0)
pixd = pixConvert1To4(NULL, pixs, 0, 15);
else /* invert bits */
pixd = pixConvert1To4(NULL, pixs, 15, 0);
}
else if (depth == 8) {
if (invert == 0)
pixd = pixConvert1To8(NULL, pixs, 0, 255);
else /* invert bits */
pixd = pixConvert1To8(NULL, pixs, 255, 0);
}
else if (depth == 16) {
if (invert == 0)
pixd = pixConvert1To16(NULL, pixs, 0, 0xffff);
else /* invert bits */
pixd = pixConvert1To16(NULL, pixs, 0xffff, 0);
}
else {
if (invert == 0)
pixd = pixConvert1To32(NULL, pixs, 0, 0xffffffff);
else /* invert bits */
pixd = pixConvert1To32(NULL, pixs, 0xffffffff, 0);
}
return pixd;
}
/*!
* pixConvert1To16()
*
* Input: pixd (<optional> 16 bpp, can be null)
* pixs (1 bpp)
* val0 (16 bit value to be used for 0s in pixs)
* val1 (16 bit value to be used for 1s in pixs)
* Return: pixd (16 bpp)
*
* Notes:
* (1) If pixd is null, a new pix is made.
* (2) If pixd is not null, it must be of equal width and height
* as pixs. It is always returned.
*/
PIX *
pixConvert1To16(PIX *pixd,
PIX *pixs,
l_uint16 val0,
l_uint16 val1)
{
l_int32 w, h, i, j, dibit, ndibits, wpls, wpld;
l_uint16 val[2];
l_uint32 index;
l_uint32 *tab, *datas, *datad, *lines, *lined;
PROCNAME("pixConvert1To16");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 1)
return (PIX *)ERROR_PTR("pixs not 1 bpp", procName, NULL);
w = pixGetWidth(pixs);
h = pixGetHeight(pixs);
if (pixd) {
if (w != pixGetWidth(pixd) || h != pixGetHeight(pixd))
return (PIX *)ERROR_PTR("pix sizes unequal", procName, pixd);
if (pixGetDepth(pixd) != 16)
return (PIX *)ERROR_PTR("pixd not 16 bpp", procName, pixd);
}
else {
if ((pixd = pixCreate(w, h, 16)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
}
pixCopyResolution(pixd, pixs);
/* Use a table to convert 2 src bits at a time */
if ((tab = (l_uint32 *)CALLOC(4, sizeof(l_uint32))) == NULL)
return (PIX *)ERROR_PTR("tab not made", procName, NULL);
val[0] = val0;
val[1] = val1;
for (index = 0; index < 4; index++) {
tab[index] = (val[(index >> 1) & 1] << 16) | val[index & 1];
}
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
ndibits = (w + 1) / 2;
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < ndibits; j++) {
dibit = GET_DATA_DIBIT(lines, j);
lined[j] = tab[dibit];
}
}
FREE(tab);
return pixd;
}
/*!
* pixConvert1To32()
*
* Input: pixd (<optional> 32 bpp, can be null)
* pixs (1 bpp)
* val0 (32 bit value to be used for 0s in pixs)
* val1 (32 bit value to be used for 1s in pixs)
* Return: pixd (32 bpp)
*
* Notes:
* (1) If pixd is null, a new pix is made.
* (2) If pixd is not null, it must be of equal width and height
* as pixs. It is always returned.
*/
PIX *
pixConvert1To32(PIX *pixd,
PIX *pixs,
l_uint32 val0,
l_uint32 val1)
{
l_int32 w, h, i, j, wpls, wpld, bit;
l_uint32 val[2];
l_uint32 *datas, *datad, *lines, *lined;
PROCNAME("pixConvert1To32");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 1)
return (PIX *)ERROR_PTR("pixs not 1 bpp", procName, NULL);
pixGetDimensions(pixs, &w, &h, NULL);
if (pixd) {
if (w != pixGetWidth(pixd) || h != pixGetHeight(pixd))
return (PIX *)ERROR_PTR("pix sizes unequal", procName, pixd);
if (pixGetDepth(pixd) != 32)
return (PIX *)ERROR_PTR("pixd not 32 bpp", procName, pixd);
}
else {
if ((pixd = pixCreate(w, h, 32)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
}
pixCopyResolution(pixd, pixs);
val[0] = val0;
val[1] = val1;
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j <w; j++) {
bit = GET_DATA_BIT(lines, j);
lined[j] = val[bit];
}
}
return pixd;
}
/*---------------------------------------------------------------------------*
* Conversion from 1 bpp to 2 bpp *
*---------------------------------------------------------------------------*/
/*!
* pixConvert1To2Cmap()
*
* Input: pixs (1 bpp)
* Return: pixd (2 bpp, cmapped)
*
* Notes:
* (1) Input 0 is mapped to (255, 255, 255); 1 is mapped to (0, 0, 0)
*/
PIX *
pixConvert1To2Cmap(PIX *pixs)
{
PIX *pixd;
PIXCMAP *cmap;
PROCNAME("pixConvert1To2Cmap");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 1)
return (PIX *)ERROR_PTR("pixs not 1 bpp", procName, NULL);
if ((pixd = pixConvert1To2(NULL, pixs, 0, 1)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
cmap = pixcmapCreate(2);
pixcmapAddColor(cmap, 255, 255, 255);
pixcmapAddColor(cmap, 0, 0, 0);
pixSetColormap(pixd, cmap);
return pixd;
}
/*!
* pixConvert1To2()
*
* Input: pixd (<optional> 2 bpp, can be null)
* pixs (1 bpp)
* val0 (2 bit value to be used for 0s in pixs)
* val1 (2 bit value to be used for 1s in pixs)
* Return: pixd (2 bpp)
*
* Notes:
* (1) If pixd is null, a new pix is made.
* (2) If pixd is not null, it must be of equal width and height
* as pixs. It is always returned.
* (3) A simple unpacking might use val0 = 0 and val1 = 3.
* (4) If you want a colormapped pixd, use pixConvert1To2Cmap().
*/
PIX *
pixConvert1To2(PIX *pixd,
PIX *pixs,
l_int32 val0,
l_int32 val1)
{
l_int32 w, h, i, j, byteval, nbytes, wpls, wpld;
l_uint8 val[2];
l_uint32 index;
l_uint16 *tab;
l_uint32 *datas, *datad, *lines, *lined;
PROCNAME("pixConvert1To2");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, pixd);
if (pixGetDepth(pixs) != 1)
return (PIX *)ERROR_PTR("pixs not 1 bpp", procName, pixd);
pixGetDimensions(pixs, &w, &h, NULL);
if (pixd) {
if (w != pixGetWidth(pixd) || h != pixGetHeight(pixd))
return (PIX *)ERROR_PTR("pix sizes unequal", procName, pixd);
if (pixGetDepth(pixd) != 2)
return (PIX *)ERROR_PTR("pixd not 2 bpp", procName, pixd);
}
else {
if ((pixd = pixCreate(w, h, 2)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
}
pixCopyResolution(pixd, pixs);
/* Use a table to convert 8 src bits to 16 dest bits */
if ((tab = (l_uint16 *)CALLOC(256, sizeof(l_uint16))) == NULL)
return (PIX *)ERROR_PTR("tab not made", procName, NULL);
val[0] = val0;
val[1] = val1;
for (index = 0; index < 256; index++) {
tab[index] = (val[(index >> 7) & 1] << 14) |
(val[(index >> 6) & 1] << 12) |
(val[(index >> 5) & 1] << 10) |
(val[(index >> 4) & 1] << 8) |
(val[(index >> 3) & 1] << 6) |
(val[(index >> 2) & 1] << 4) |
(val[(index >> 1) & 1] << 2) | val[index & 1];
}
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
nbytes = (w + 7) / 8;
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < nbytes; j++) {
byteval = GET_DATA_BYTE(lines, j);
SET_DATA_TWO_BYTES(lined, j, tab[byteval]);
}
}
FREE(tab);
return pixd;
}
/*---------------------------------------------------------------------------*
* Conversion from 1 bpp to 4 bpp *
*---------------------------------------------------------------------------*/
/*!
* pixConvert1To4Cmap()
*
* Input: pixs (1 bpp)
* Return: pixd (4 bpp, cmapped)
*
* Notes:
* (1) Input 0 is mapped to (255, 255, 255); 1 is mapped to (0, 0, 0)
*/
PIX *
pixConvert1To4Cmap(PIX *pixs)
{
PIX *pixd;
PIXCMAP *cmap;
PROCNAME("pixConvert1To4Cmap");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 1)
return (PIX *)ERROR_PTR("pixs not 1 bpp", procName, NULL);
if ((pixd = pixConvert1To4(NULL, pixs, 0, 1)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
cmap = pixcmapCreate(4);
pixcmapAddColor(cmap, 255, 255, 255);
pixcmapAddColor(cmap, 0, 0, 0);
pixSetColormap(pixd, cmap);
return pixd;
}
/*!
* pixConvert1To4()
*
* Input: pixd (<optional> 4 bpp, can be null)
* pixs (1 bpp)
* val0 (4 bit value to be used for 0s in pixs)
* val1 (4 bit value to be used for 1s in pixs)
* Return: pixd (4 bpp)
*
* Notes:
* (1) If pixd is null, a new pix is made.
* (2) If pixd is not null, it must be of equal width and height
* as pixs. It is always returned.
* (3) A simple unpacking might use val0 = 0 and val1 = 15, or v.v.
* (4) If you want a colormapped pixd, use pixConvert1To4Cmap().
*/
PIX *
pixConvert1To4(PIX *pixd,
PIX *pixs,
l_int32 val0,
l_int32 val1)
{
l_int32 w, h, i, j, byteval, nbytes, wpls, wpld;
l_uint8 val[2];
l_uint32 index;
l_uint32 *tab, *datas, *datad, *lines, *lined;
PROCNAME("pixConvert1To4");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, pixd);
if (pixGetDepth(pixs) != 1)
return (PIX *)ERROR_PTR("pixs not 1 bpp", procName, pixd);
pixGetDimensions(pixs, &w, &h, NULL);
if (pixd) {
if (w != pixGetWidth(pixd) || h != pixGetHeight(pixd))
return (PIX *)ERROR_PTR("pix sizes unequal", procName, pixd);
if (pixGetDepth(pixd) != 4)
return (PIX *)ERROR_PTR("pixd not 4 bpp", procName, pixd);
}
else {
if ((pixd = pixCreate(w, h, 4)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
}
pixCopyResolution(pixd, pixs);
/* Use a table to convert 8 src bits to 32 bit dest word */
if ((tab = (l_uint32 *)CALLOC(256, sizeof(l_uint32))) == NULL)
return (PIX *)ERROR_PTR("tab not made", procName, NULL);
val[0] = val0;
val[1] = val1;
for (index = 0; index < 256; index++) {
tab[index] = (val[(index >> 7) & 1] << 28) |
(val[(index >> 6) & 1] << 24) |
(val[(index >> 5) & 1] << 20) |
(val[(index >> 4) & 1] << 16) |
(val[(index >> 3) & 1] << 12) |
(val[(index >> 2) & 1] << 8) |
(val[(index >> 1) & 1] << 4) | val[index & 1];
}
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
nbytes = (w + 7) / 8;
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < nbytes; j++) {
byteval = GET_DATA_BYTE(lines, j);
lined[j] = tab[byteval];
}
}
FREE(tab);
return pixd;
}
/*---------------------------------------------------------------------------*
* Conversion from 1, 2 and 4 bpp to 8 bpp *
*---------------------------------------------------------------------------*/
/*!
* pixConvert1To8()
*
* Input: pixd (<optional> 8 bpp, can be null)
* pixs (1 bpp)
* val0 (8 bit value to be used for 0s in pixs)
* val1 (8 bit value to be used for 1s in pixs)
* Return: pixd (8 bpp)
*
* Notes:
* (1) If pixd is null, a new pix is made.
* (2) If pixd is not null, it must be of equal width and height
* as pixs. It is always returned.
* (3) A simple unpacking might use val0 = 0 and val1 = 255, or v.v.
* (4) In a typical application where one wants to use a colormap
* with the dest, you can use val0 = 0, val1 = 1 to make a
* non-cmapped 8 bpp pix, and then make a colormap and set 0
* and 1 to the desired colors. Here is an example:
* pixd = pixConvert1To8(NULL, pixs, 0, 1);
* cmap = pixCreate(8);
* pixcmapAddColor(cmap, 255, 255, 255);
* pixcmapAddColor(cmap, 0, 0, 0);
* pixSetColormap(pixd, cmap);
*/
PIX *
pixConvert1To8(PIX *pixd,
PIX *pixs,
l_uint8 val0,
l_uint8 val1)
{
l_int32 w, h, i, j, qbit, nqbits, wpls, wpld;
l_uint8 val[2];
l_uint32 index;
l_uint32 *tab, *datas, *datad, *lines, *lined;
PROCNAME("pixConvert1To8");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, pixd);
if (pixGetDepth(pixs) != 1)
return (PIX *)ERROR_PTR("pixs not 1 bpp", procName, pixd);
pixGetDimensions(pixs, &w, &h, NULL);
if (pixd) {
if (w != pixGetWidth(pixd) || h != pixGetHeight(pixd))
return (PIX *)ERROR_PTR("pix sizes unequal", procName, pixd);
if (pixGetDepth(pixd) != 8)
return (PIX *)ERROR_PTR("pixd not 8 bpp", procName, pixd);
}
else {
if ((pixd = pixCreate(w, h, 8)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
}
pixCopyResolution(pixd, pixs);
/* Use a table to convert 4 src bits at a time */
if ((tab = (l_uint32 *)CALLOC(16, sizeof(l_uint32))) == NULL)
return (PIX *)ERROR_PTR("tab not made", procName, NULL);
val[0] = val0;
val[1] = val1;
for (index = 0; index < 16; index++) {
tab[index] = (val[(index >> 3) & 1] << 24) |
(val[(index >> 2) & 1] << 16) |
(val[(index >> 1) & 1] << 8) | val[index & 1];
}
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
nqbits = (w + 3) / 4;
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < nqbits; j++) {
qbit = GET_DATA_QBIT(lines, j);
lined[j] = tab[qbit];
}
}
FREE(tab);
return pixd;
}
/*!
* pixConvert2To8()
*
* Input: pixs (2 bpp)
* val0 (8 bit value to be used for 00 in pixs)
* val1 (8 bit value to be used for 01 in pixs)
* val2 (8 bit value to be used for 10 in pixs)
* val3 (8 bit value to be used for 11 in pixs)
* cmapflag (TRUE if pixd is to have a colormap; FALSE otherwise)
* Return: pixd (8 bpp), or null on error
*
* Notes:
* - A simple unpacking might use val0 = 0,
* val1 = 85 (0x55), val2 = 170 (0xaa), val3 = 255.
* - If cmapflag is TRUE:
* - The 8 bpp image is made with a colormap.
* - If pixs has a colormap, the input values are ignored and
* the 8 bpp image is made using the colormap
* - If pixs does not have a colormap, the input values are
* used to build the colormap.
* - If cmapflag is FALSE:
* - The 8 bpp image is made without a colormap.
* - If pixs has a colormap, the input values are ignored,
* the colormap is removed, and the values stored in the 8 bpp
* image are from the colormap.
* - If pixs does not have a colormap, the input values are
* used to populate the 8 bpp image.
*/
PIX *
pixConvert2To8(PIX *pixs,
l_uint8 val0,
l_uint8 val1,
l_uint8 val2,
l_uint8 val3,
l_int32 cmapflag)
{
l_int32 w, h, i, j, nbytes, wpls, wpld, dibit, ncolor;
l_int32 rval, gval, bval, byte;
l_uint8 val[4];
l_uint32 index;
l_uint32 *tab, *datas, *datad, *lines, *lined;
PIX *pixd;
PIXCMAP *cmaps, *cmapd;
PROCNAME("pixConvert2To8");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 2)
return (PIX *)ERROR_PTR("pixs not 2 bpp", procName, NULL);
cmaps = pixGetColormap(pixs);
if (cmaps && cmapflag == FALSE)
return pixRemoveColormap(pixs, REMOVE_CMAP_TO_GRAYSCALE);
pixGetDimensions(pixs, &w, &h, NULL);
if ((pixd = pixCreate(w, h, 8)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
pixCopyResolution(pixd, pixs);
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
if (cmapflag == TRUE) { /* pixd will have a colormap */
cmapd = pixcmapCreate(8); /* 8 bpp standard cmap */
if (cmaps) { /* use the existing colormap from pixs */
ncolor = pixcmapGetCount(cmaps);
for (i = 0; i < ncolor; i++) {
pixcmapGetColor(cmaps, i, &rval, &gval, &bval);
pixcmapAddColor(cmapd, rval, gval, bval);
}
}
else { /* make a colormap from the input values */
pixcmapAddColor(cmapd, val0, val0, val0);
pixcmapAddColor(cmapd, val1, val1, val1);
pixcmapAddColor(cmapd, val2, val2, val2);
pixcmapAddColor(cmapd, val3, val3, val3);
}
pixSetColormap(pixd, cmapd);
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
dibit = GET_DATA_DIBIT(lines, j);
SET_DATA_BYTE(lined, j, dibit);
}
}
return pixd;
}
/* Last case: no colormap in either pixs or pixd.
* Use input values and build a table to convert 1 src byte
* (4 src pixels) at a time */
if ((tab = (l_uint32 *)CALLOC(256, sizeof(l_uint32))) == NULL)
return (PIX *)ERROR_PTR("tab not made", procName, NULL);
val[0] = val0;
val[1] = val1;
val[2] = val2;
val[3] = val3;
for (index = 0; index < 256; index++) {
tab[index] = (val[(index >> 6) & 3] << 24) |
(val[(index >> 4) & 3] << 16) |
(val[(index >> 2) & 3] << 8) | val[index & 3];
}
nbytes = (w + 3) / 4;
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < nbytes; j++) {
byte = GET_DATA_BYTE(lines, j);
lined[j] = tab[byte];
}
}
FREE(tab);
return pixd;
}
/*!
* pixConvert4To8()
*
* Input: pixs (4 bpp)
* cmapflag (TRUE if pixd is to have a colormap; FALSE otherwise)
* Return: pixd (8 bpp), or null on error
*
* Notes:
* - If cmapflag is TRUE:
* - pixd is made with a colormap.
* - If pixs has a colormap, it is copied and the colormap
* index values are placed in pixd.
* - If pixs does not have a colormap, a colormap with linear
* trc is built and the pixel values in pixs are placed in
* pixd as colormap index values.
* - If cmapflag is FALSE:
* - pixd is made without a colormap.
* - If pixs has a colormap, it is removed and the values stored
* in pixd are from the colormap (converted to gray).
* - If pixs does not have a colormap, the pixel values in pixs
* are used, with shift replication, to populate pixd.
*/
PIX *
pixConvert4To8(PIX *pixs,
l_int32 cmapflag)
{
l_int32 w, h, i, j, wpls, wpld, ncolor;
l_int32 rval, gval, bval, byte, qbit;
l_uint32 *datas, *datad, *lines, *lined;
PIX *pixd;
PIXCMAP *cmaps, *cmapd;
PROCNAME("pixConvert4To8");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 4)
return (PIX *)ERROR_PTR("pixs not 4 bpp", procName, NULL);
cmaps = pixGetColormap(pixs);
if (cmaps && cmapflag == FALSE)
return pixRemoveColormap(pixs, REMOVE_CMAP_TO_GRAYSCALE);
pixGetDimensions(pixs, &w, &h, NULL);
if ((pixd = pixCreate(w, h, 8)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
pixCopyResolution(pixd, pixs);
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
if (cmapflag == TRUE) { /* pixd will have a colormap */
cmapd = pixcmapCreate(8);
if (cmaps) { /* use the existing colormap from pixs */
ncolor = pixcmapGetCount(cmaps);
for (i = 0; i < ncolor; i++) {
pixcmapGetColor(cmaps, i, &rval, &gval, &bval);
pixcmapAddColor(cmapd, rval, gval, bval);
}
}
else { /* make a colormap with a linear trc */
for (i = 0; i < 16; i++)
pixcmapAddColor(cmapd, 17 * i, 17 * i, 17 * i);
}
pixSetColormap(pixd, cmapd);
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
qbit = GET_DATA_QBIT(lines, j);
SET_DATA_BYTE(lined, j, qbit);
}
}
return pixd;
}
/* Last case: no colormap in either pixs or pixd.
* Replicate the qbit value into 8 bits. */
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
qbit = GET_DATA_QBIT(lines, j);
byte = (qbit << 4) | qbit;
SET_DATA_BYTE(lined, j, byte);
}
}
return pixd;
}
/*---------------------------------------------------------------------------*
* Unpacking conversion from 8 bpp to 16 bpp *
*---------------------------------------------------------------------------*/
/*!
* pixConvert8To16()
*
* Input: pixs (8 bpp; colormap removed to gray)
* leftshift (number of bits: 0 is no shift;
* 8 replicates in MSB and LSB of dest)
* Return: pixd (16 bpp), or null on error
*
* Notes:
* (1) For left shift of 8, the 8 bit value is replicated in both
* the MSB and the LSB of the pixels in pixd. That way, we get
* proportional mapping, with a correct map from 8 bpp white
* (0xff) to 16 bpp white (0xffff).
*/
PIX *
pixConvert8To16(PIX *pixs,
l_int32 leftshift)
{
l_int32 i, j, w, h, d, wplt, wpld, val;
l_uint32 *datat, *datad, *linet, *lined;
PIX *pixt, *pixd;
PROCNAME("pixConvert8To16");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
pixGetDimensions(pixs, &w, &h, &d);
if (d != 8)
return (PIX *)ERROR_PTR("pixs not 8 bpp", procName, NULL);
if (leftshift < 0 || leftshift > 8)
return (PIX *)ERROR_PTR("leftshift not in [0 ... 8]", procName, NULL);
if (pixGetColormap(pixs) != NULL)
pixt = pixRemoveColormap(pixs, REMOVE_CMAP_TO_GRAYSCALE);
else
pixt = pixClone(pixs);
pixd = pixCreate(w, h, 16);
datat = pixGetData(pixt);
datad = pixGetData(pixd);
wplt = pixGetWpl(pixt);
wpld = pixGetWpl(pixd);
for (i = 0; i < h; i++) {
linet = datat + i * wplt;
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
val = GET_DATA_BYTE(linet, j);
if (leftshift == 8)
val = val | (val << leftshift);
else
val <<= leftshift;
SET_DATA_TWO_BYTES(lined, j, val);
}
}
pixDestroy(&pixt);
return pixd;
}
/*---------------------------------------------------------------------------*
* Top-level conversion to 1 bpp *
*---------------------------------------------------------------------------*/
/*!
* pixConvertTo1()
*
* Input: pixs (1, 2, 4, 8, 16 or 32 bpp)
* threshold (for final binarization, relative to 8 bpp)
* Return: pixd (1 bpp), or null on error
*
* Notes:
* (1) This is a top-level function, with simple default values
* used in pixConvertTo8() if unpacking is necessary.
* (2) Any existing colormap is removed.
* (3) If the input image has 1 bpp and no colormap, the operation is
* lossless and a copy is returned.
*/
PIX *
pixConvertTo1(PIX *pixs,
l_int32 threshold)
{
l_int32 d, color0, color1, rval, gval, bval;
PIX *pixg, *pixd;
PIXCMAP *cmap;
PROCNAME("pixConvertTo1");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
d = pixGetDepth(pixs);
if (d != 1 && d != 2 && d != 4 && d != 8 && d != 16 && d != 32)
return (PIX *)ERROR_PTR("depth not {1,2,4,8,16,32}", procName, NULL);
cmap = pixGetColormap(pixs);
if (d == 1) {
if (!cmap)
return pixCopy(NULL, pixs);
else { /* strip the colormap off, and invert if reasonable
for standard binary photometry. */
pixcmapGetColor(cmap, 0, &rval, &gval, &bval);
color0 = rval + gval + bval;
pixcmapGetColor(cmap, 1, &rval, &gval, &bval);
color1 = rval + gval + bval;
pixd = pixCopy(NULL, pixs);
pixDestroyColormap(pixd);
if (color1 > color0)
pixInvert(pixd, pixd);
return pixd;
}
}
/* For all other depths, use 8 bpp as an intermediary */
pixg = pixConvertTo8(pixs, FALSE);
pixd = pixThresholdToBinary(pixg, threshold);
pixDestroy(&pixg);
return pixd;
}
/*!
* pixConvertTo1BySampling()
*
* Input: pixs (1, 2, 4, 8, 16 or 32 bpp)
* factor (submsampling factor; integer >= 1)
* threshold (for final binarization, relative to 8 bpp)
* Return: pixd (1 bpp), or null on error
*
* Notes:
* (1) This is a fast, quick/dirty, top-level converter.
* (2) See pixConvertTo1() for default values.
*/
PIX *
pixConvertTo1BySampling(PIX *pixs,
l_int32 factor,
l_int32 threshold)
{
l_float32 scalefactor;
PIX *pixt, *pixd;
PROCNAME("pixConvertTo1BySampling");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (factor < 1)
return (PIX *)ERROR_PTR("factor must be >= 1", procName, NULL);
scalefactor = 1. / (l_float32)factor;
pixt = pixScaleBySampling(pixs, scalefactor, scalefactor);
pixd = pixConvertTo1(pixt, threshold);
pixDestroy(&pixt);
return pixd;
}
/*---------------------------------------------------------------------------*
* Top-level conversion to 8 bpp *
*---------------------------------------------------------------------------*/
/*!
* pixConvertTo8()
*
* Input: pixs (1, 2, 4, 8, 16 or 32 bpp)
* cmapflag (TRUE if pixd is to have a colormap; FALSE otherwise)
* Return: pixd (8 bpp), or null on error
*
* Notes:
* (1) This is a top-level function, with simple default values
* for unpacking.
* (2) The result, pixd, is made with a colormap if specified.
* (3) If d == 8, and cmapflag matches the existence of a cmap
* in pixs, the operation is lossless and it returns a copy.
* (4) The default values used are:
* - 1 bpp: val0 = 255, val1 = 0
* - 2 bpp: 4 bpp: even increments over dynamic range
* - 8 bpp: lossless if cmap matches cmapflag
* - 16 bpp: use most significant byte
* (5) If 32 bpp RGB, this is converted to gray. If you want
* to do color quantization, you must specify the type
* explicitly, using the color quantization code.
*/
PIX *
pixConvertTo8(PIX *pixs,
l_int32 cmapflag)
{
l_int32 d;
PIX *pixd;
PIXCMAP *cmap;
PROCNAME("pixConvertTo8");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
d = pixGetDepth(pixs);
if (d != 1 && d != 2 && d != 4 && d != 8 && d != 16 && d != 32)
return (PIX *)ERROR_PTR("depth not {1,2,4,8,16,32}", procName, NULL);
if (d == 1) {
if (!cmapflag)
return pixConvert1To8(NULL, pixs, 255, 0);
else {
pixd = pixConvert1To8(NULL, pixs, 0, 1);
cmap = pixcmapCreate(8);
pixcmapAddColor(cmap, 255, 255, 255);
pixcmapAddColor(cmap, 0, 0, 0);
pixSetColormap(pixd, cmap);
return pixd;
}
}
else if (d == 2)
return pixConvert2To8(pixs, 0, 85, 170, 255, cmapflag);
else if (d == 4)
return pixConvert4To8(pixs, cmapflag);
else if (d == 8) {
cmap = pixGetColormap(pixs);
if ((cmap && cmapflag) || (!cmap && !cmapflag))
return pixCopy(NULL, pixs);
else if (cmap) /* !cmapflag */
return pixRemoveColormap(pixs, REMOVE_CMAP_TO_GRAYSCALE);
else { /* !cmap && cmapflag; add colormap to pixd */
pixd = pixCopy(NULL, pixs);
pixAddGrayColormap8(pixd);
return pixd;
}
}
else if (d == 16) {
pixd = pixConvert16To8(pixs, 1);
if (cmapflag)
pixAddGrayColormap8(pixd);
return pixd;
}
else { /* d == 32 */
pixd = pixConvertRGBToLuminance(pixs);
if (cmapflag)
pixAddGrayColormap8(pixd);
return pixd;
}
}
/*!
* pixConvertTo8BySampling()
*
* Input: pixs (1, 2, 4, 8, 16 or 32 bpp)
* factor (submsampling factor; integer >= 1)
* cmapflag (TRUE if pixd is to have a colormap; FALSE otherwise)
* Return: pixd (8 bpp), or null on error
*
* Notes:
* (1) This is a fast, quick/dirty, top-level converter.
* (2) See pixConvertTo8() for default values.
*/
PIX *
pixConvertTo8BySampling(PIX *pixs,
l_int32 factor,
l_int32 cmapflag)
{
l_float32 scalefactor;
PIX *pixt, *pixd;
PROCNAME("pixConvertTo8BySampling");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (factor < 1)
return (PIX *)ERROR_PTR("factor must be >= 1", procName, NULL);
scalefactor = 1. / (l_float32)factor;
pixt = pixScaleBySampling(pixs, scalefactor, scalefactor);
pixd = pixConvertTo8(pixt, cmapflag);
pixDestroy(&pixt);
return pixd;
}
/*---------------------------------------------------------------------------*
* Top-level conversion to 16 bpp *
*---------------------------------------------------------------------------*/
/*!
* pixConvertTo16()
*
* Input: pixs (1, 8 bpp)
* Return: pixd (16 bpp), or null on error
*
* Usage: Top-level function, with simple default values for unpacking.
* 1 bpp: val0 = 0xffff, val1 = 0
* 8 bpp: replicates the 8 bit value in both the MSB and LSB
* of the 16 bit pixel.
*/
PIX *
pixConvertTo16(PIX *pixs)
{
l_int32 d;
PROCNAME("pixConvertTo16");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
d = pixGetDepth(pixs);
if (d == 1)
return pixConvert1To16(NULL, pixs, 0xffff, 0);
else if (d == 8)
return pixConvert8To16(pixs, 8);
else
return (PIX *)ERROR_PTR("src depth not 1 or 8 bpp", procName, NULL);
}
/*---------------------------------------------------------------------------*
* Top-level conversion to 32 bpp *
*---------------------------------------------------------------------------*/
/*!
* pixConvertTo32()
*
* Input: pixs (1, 2, 4, 8, 16 or 32 bpp)
* Return: pixd (32 bpp), or null on error
*
* Usage: Top-level function, with simple default values for unpacking.
* 1 bpp: val0 = 255, val1 = 0
* and then replication into R, G and B components
* 2 bpp: if colormapped, use the colormap values; otherwise,
* use val0 = 0, val1 = 0x55, val2 = 0xaa, val3 = 255
* and replicate gray into R, G and B components
* 4 bpp: if colormapped, use the colormap values; otherwise,
* replicate 2 nybs into a byte, and then into R,G,B components
* 8 bpp: if colormapped, use the colormap values; otherwise,
* replicate gray values into R, G and B components
* 16 bpp: replicate MSB into R, G and B components
* 32 bpp: makes a copy
*
* Notes:
* (1) Implicit assumption about RGB component ordering.
*/
PIX *
pixConvertTo32(PIX *pixs)
{
l_int32 d;
PIX *pixt, *pixd;
PROCNAME("pixConvertTo32");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
d = pixGetDepth(pixs);
if (d == 1)
return pixConvert1To32(NULL, pixs, 0xffffffff, 0);
else if (d == 2) {
pixt = pixConvert2To8(pixs, 0, 85, 170, 255, TRUE);
pixd = pixConvert8To32(pixt);
pixDestroy(&pixt);
return pixd;
}
else if (d == 4) {
pixt = pixConvert4To8(pixs, TRUE);
pixd = pixConvert8To32(pixt);
pixDestroy(&pixt);
return pixd;
}
else if (d == 8)
return pixConvert8To32(pixs);
else if (d == 16) {
pixt = pixConvert16To8(pixs, 1);
pixd = pixConvert8To32(pixt);
pixDestroy(&pixt);
return pixd;
}
else if (d == 32)
return pixCopy(NULL, pixs);
else
return (PIX *)ERROR_PTR("depth not 1, 2, 4, 8, 16, 32 bpp",
procName, NULL);
}
/*!
* pixConvertTo32BySampling()
*
* Input: pixs (1, 2, 4, 8, 16 or 32 bpp)
* factor (submsampling factor; integer >= 1)
* Return: pixd (32 bpp), or null on error
*
* Notes:
* (1) This is a fast, quick/dirty, top-level converter.
* (2) See pixConvertTo32() for default values.
*/
PIX *
pixConvertTo32BySampling(PIX *pixs,
l_int32 factor)
{
l_float32 scalefactor;
PIX *pixt, *pixd;
PROCNAME("pixConvertTo32BySampling");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (factor < 1)
return (PIX *)ERROR_PTR("factor must be >= 1", procName, NULL);
scalefactor = 1. / (l_float32)factor;
pixt = pixScaleBySampling(pixs, scalefactor, scalefactor);
pixd = pixConvertTo32(pixt);
pixDestroy(&pixt);
return pixd;
}
/*!
* pixConvert8To32()
*
* Input: pix (8 bpp)
* Return: 32 bpp rgb pix, or null on error
*
* Notes:
* (1) If there is no colormap, replicates the gray value
* into the 3 MSB of the dest pixel.
* (2) Implicit assumption about RGB component ordering.
*/
PIX *
pixConvert8To32(PIX *pixs)
{
l_int32 i, j, w, h, wpls, wpld, val;
l_uint32 *datas, *datad, *lines, *lined;
l_uint32 *tab;
PIX *pixd;
PROCNAME("pixConvert8To32");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 8)
return (PIX *)ERROR_PTR("pixs not 8 bpp", procName, NULL);
if (pixGetColormap(pixs))
return pixRemoveColormap(pixs, REMOVE_CMAP_TO_FULL_COLOR);
/* Replication table */
if ((tab = (l_uint32 *)CALLOC(256, sizeof(l_uint32))) == NULL)
return (PIX *)ERROR_PTR("tab not made", procName, NULL);
for (i = 0; i < 256; i++)
tab[i] = (i << 24) | (i << 16) | (i << 8);
pixGetDimensions(pixs, &w, &h, NULL);
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
if ((pixd = pixCreate(w, h, 32)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
pixCopyResolution(pixd, pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
val = GET_DATA_BYTE(lines, j);
lined[j] = tab[val];
}
}
FREE(tab);
return pixd;
}
/*---------------------------------------------------------------------------*
* Top-level conversion to 8 or 32 bpp, without colormap *
*---------------------------------------------------------------------------*/
/*!
* pixConvertTo8Or32()
*
* Input: pixs (1, 2, 4, 8, 16, with or without colormap; or 32 bpp rgb)
* copyflag (use 0 to return clone if pixs does not need to
* be changed; 1 to return a copy in those situations)
* warnflag (1 to issue warning if colormap is removed; else 0)
* Return: pixd (8 bpp grayscale or 32 bpp rgb), or null on error
*
* Notes:
* (1) If there is a colormap, the colormap is removed to 8 or 32 bpp,
* depending on whether the colors in the colormap are all gray.
* (2) If the input is either rgb or 8 bpp without a colormap,
* this returns either a clone or a copy, depending on @copyflag.
* (3) Otherwise, the pix is converted to 8 bpp grayscale.
* In all cases, pixd does not have a colormap.
*/
PIX *
pixConvertTo8Or32(PIX *pixs,
l_int32 copyflag,
l_int32 warnflag)
{
l_int32 d;
PIX *pixd;
PROCNAME("pixConvertTo8Or32");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
d = pixGetDepth(pixs);
if (pixGetColormap(pixs)) {
if (warnflag) L_WARNING("pix has colormap; removing", procName);
pixd = pixRemoveColormap(pixs, REMOVE_CMAP_BASED_ON_SRC);
}
else if (d == 8 || d == 32) {
if (copyflag == 0)
pixd = pixClone(pixs);
else
pixd = pixCopy(NULL, pixs);
}
else
pixd = pixConvertTo8(pixs, 0);
/* Sanity check on result */
d = pixGetDepth(pixd);
if (d != 8 && d != 32) {
pixDestroy(&pixd);
return (PIX *)ERROR_PTR("depth not 8 or 32 bpp", procName, NULL);
}
return pixd;
}
/*---------------------------------------------------------------------------*
* Lossless depth conversion (unpacking) *
*---------------------------------------------------------------------------*/
/*!
* pixConvertLossless()
*
* Input: pixs (1, 2, 4, 8 bpp, not cmapped)
* d (destination depth: 2, 4 or 8)
* Return: pixd (2, 4 or 8 bpp), or null on error
*
* Notes:
* (1) This is a lossless unpacking (depth-increasing)
* conversion. If ds is the depth of pixs, then
* - if d < ds, returns NULL
* - if d == ds, returns a copy
* - if d > ds, does the unpacking conversion
* (2) If pixs has a colormap, this is an error.
*/
PIX *
pixConvertLossless(PIX *pixs,
l_int32 d)
{
l_int32 w, h, ds, wpls, wpld, i, j, val;
l_uint32 *datas, *datad, *lines, *lined;
PIX *pixd;
PROCNAME("pixConvertLossless");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetColormap(pixs))
return (PIX *)ERROR_PTR("pixs has colormap", procName, NULL);
if (d != 2 && d != 4 && d != 8)
return (PIX *)ERROR_PTR("invalid dest depth", procName, NULL);
pixGetDimensions(pixs, &w, &h, &ds);
if (d < ds)
return (PIX *)ERROR_PTR("depth > d", procName, NULL);
else if (d == ds)
return pixCopy(NULL, pixs);
if ((pixd = pixCreate(w, h, d)) == NULL)
return (PIX *)ERROR_PTR("pixd not made", procName, NULL);
pixCopyResolution(pixd, pixs);
/* Unpack the bits */
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
switch (ds)
{
case 1:
for (j = 0; j < w; j++) {
val = GET_DATA_BIT(lines, j);
if (d == 8)
SET_DATA_BYTE(lined, j, val);
else if (d == 4)
SET_DATA_QBIT(lined, j, val);
else /* d == 2 */
SET_DATA_DIBIT(lined, j, val);
}
break;
case 2:
for (j = 0; j < w; j++) {
val = GET_DATA_DIBIT(lines, j);
if (d == 8)
SET_DATA_BYTE(lined, j, val);
else /* d == 4 */
SET_DATA_QBIT(lined, j, val);
}
case 4:
for (j = 0; j < w; j++) {
val = GET_DATA_DIBIT(lines, j);
SET_DATA_BYTE(lined, j, val);
}
break;
}
}
return pixd;
}
/*---------------------------------------------------------------------------*
* Conversion for printing in PostScript *
*---------------------------------------------------------------------------*/
/*!
* pixConvertForPSWrap()
*
* Input: pixs (1, 2, 4, 8, 16, 32 bpp)
* Return: pixd (1, 8, or 32 bpp), or null on error
*
* Notes:
* (1) For wrapping in PostScript, we convert pixs to
* 1 bpp, 8 bpp (gray) and 32 bpp (RGB color).
* (2) Colormaps are removed. For pixs with colormaps, the
* images are converted to either 8 bpp gray or 32 bpp
* RGB, depending on whether the colormap has color content.
* (3) Images without colormaps, that are not 1 bpp or 32 bpp,
* are converted to 8 bpp gray.
*/
PIX *
pixConvertForPSWrap(PIX *pixs)
{
l_int32 d;
PIX *pixd;
PIXCMAP *cmap;
PROCNAME("pixConvertForPSWrap");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
cmap = pixGetColormap(pixs);
d = pixGetDepth(pixs);
switch (d)
{
case 1:
case 32:
pixd = pixClone(pixs);
break;
case 2:
if (cmap)
pixd = pixRemoveColormap(pixs, REMOVE_CMAP_BASED_ON_SRC);
else
pixd = pixConvert2To8(pixs, 0, 0x55, 0xaa, 0xff, FALSE);
break;
case 4:
if (cmap)
pixd = pixRemoveColormap(pixs, REMOVE_CMAP_BASED_ON_SRC);
else
pixd = pixConvert4To8(pixs, FALSE);
break;
case 8:
pixd = pixRemoveColormap(pixs, REMOVE_CMAP_BASED_ON_SRC);
break;
case 16:
pixd = pixConvert16To8(pixs, 1);
break;
default:
fprintf(stderr, "depth not in {1, 2, 4, 8, 16, 32}");
return NULL;
}
return pixd;
}
/*---------------------------------------------------------------------------*
* Colorspace conversion between RGB and HSB *
*---------------------------------------------------------------------------*/
/*!
* pixConvertRGBToHSV()
*
* Input: pixd (can be NULL; if not NULL, must == pixs)
* pixs
* Return: pixd always
*
* Notes:
* (1) For pixs = pixd, this is in-place; otherwise pixd must be NULL.
* (2) The definition of our HSV space is given in convertRGBToHSV().
* (3) The h, s and v values are stored in the same places as
* the r, g and b values, respectively. Here, they are explicitly
* placed in the 3 MS bytes in the pixel.
* (4) Normalizing to 1 and considering the r,g,b components,
* a simple way to understand the HSV space is:
* - v = max(r,g,b)
* - s = (max - min) / max
* - h ~ (mid - min) / (max - min) [apart from signs and constants]
* (5) Normalizing to 1, some properties of the HSV space are:
* - For gray values (r = g = b) along the continuum between
* black and white:
* s = 0 (becoming undefined as you approach black)
* h is undefined everywhere
* - Where one component is saturated and the others are zero:
* v = 1
* s = 1
* h = 0 (r = max), 1/3 (g = max), 2/3 (b = max)
* - Where two components are saturated and the other is zero:
* v = 1
* s = 1
* h = 1/2 (if r = 0), 5/6 (if g = 0), 1/6 (if b = 0)
*/
PIX *
pixConvertRGBToHSV(PIX *pixd,
PIX *pixs)
{
l_int32 w, h, d, wpl, i, j, rval, gval, bval, hval, sval, vval;
l_uint32 pixel;
l_uint32 *line, *data;
PIXCMAP *cmap;
PROCNAME("pixConvertRGBToHSV");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, pixd);
if (pixd && pixd != pixs)
return (PIX *)ERROR_PTR("pixd defined and not inplace", procName, pixd);
d = pixGetDepth(pixs);
cmap = pixGetColormap(pixs);
if (!cmap && d != 32)
return (PIX *)ERROR_PTR("not cmapped or rgb", procName, pixd);
if (!pixd)
pixd = pixCopy(NULL, pixs);
cmap = pixGetColormap(pixd);
if (cmap) { /* just convert the colormap */
pixcmapConvertRGBToHSV(cmap);
return pixd;
}
/* Convert RGB image */
pixGetDimensions(pixd, &w, &h, NULL);
wpl = pixGetWpl(pixd);
data = pixGetData(pixd);
for (i = 0; i < h; i++) {
line = data + i * wpl;
for (j = 0; j < w; j++) {
pixel = line[j];
extractRGBValues(pixel, &rval, &gval, &bval);
convertRGBToHSV(rval, gval, bval, &hval, &sval, &vval);
line[j] = (hval << 24) | (sval << 16) | (vval << 8);
}
}
return pixd;
}
/*!
* pixConvertHSVToRGB()
*
* Input: pixd (can be NULL; if not NULL, must == pixs)
* pixs
* Return: pixd always
*
* Notes:
* (1) For pixs = pixd, this is in-place; otherwise pixd must be NULL.
* (2) The user takes responsibility for making sure that pixs is
* in our HSV space. The definition of our HSV space is given
* in convertRGBToHSV().
* (3) The h, s and v values are stored in the same places as
* the r, g and b values, respectively. Here, they are explicitly
* placed in the 3 MS bytes in the pixel.
*/
PIX *
pixConvertHSVToRGB(PIX *pixd,
PIX *pixs)
{
l_int32 w, h, d, wpl, i, j, rval, gval, bval, hval, sval, vval;
l_uint32 pixel;
l_uint32 *line, *data;
PIXCMAP *cmap;
PROCNAME("pixConvertHSVToRGB");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, pixd);
if (pixd && pixd != pixs)
return (PIX *)ERROR_PTR("pixd defined and not inplace", procName, pixd);
d = pixGetDepth(pixs);
cmap = pixGetColormap(pixs);
if (!cmap && d != 32)
return (PIX *)ERROR_PTR("not cmapped or hsv", procName, pixd);
if (!pixd)
pixd = pixCopy(NULL, pixs);
cmap = pixGetColormap(pixd);
if (cmap) { /* just convert the colormap */
pixcmapConvertHSVToRGB(cmap);
return pixd;
}
/* Convert HSV image */
pixGetDimensions(pixd, &w, &h, NULL);
wpl = pixGetWpl(pixd);
data = pixGetData(pixd);
for (i = 0; i < h; i++) {
line = data + i * wpl;
for (j = 0; j < w; j++) {
pixel = line[j];
hval = pixel >> 24;
sval = (pixel >> 16) & 0xff;
vval = (pixel >> 8) & 0xff;
convertHSVToRGB(hval, sval, vval, &rval, &gval, &bval);
composeRGBPixel(rval, gval, bval, line + j);
}
}
return pixd;
}
/*!
* convertRGBToHSV()
*
* Input: rval, gval, bval (RGB input)
* &hval, &sval, &vval (<return> HSV values)
* Return: 0 if OK, 1 on error
*
* Notes:
* (1) The range of returned values is:
* h [0 ... 239]
* s [0 ... 255]
* v [0 ... 255]
* (2) If r = g = b, the pixel is gray (s = 0), and we define h = 0.
* (3) h wraps around, so that h = 0 and h = 240 are equivalent
* in hue space.
* (4) h has the following correspondence to color:
* h = 0 magenta
* h = 40 red
* h = 80 yellow
* h = 120 green
* h = 160 cyan
* h = 200 blue
*/
l_int32
convertRGBToHSV(l_int32 rval,
l_int32 gval,
l_int32 bval,
l_int32 *phval,
l_int32 *psval,
l_int32 *pvval)
{
l_int32 minrg, maxrg, min, max, delta;
l_float32 h;
PROCNAME("convertRGBToHSV");
if (!phval || !psval || !pvval)
return ERROR_INT("&hval, &sval, &vval not all defined", procName, 1);
minrg = L_MIN(rval, gval);
min = L_MIN(minrg, bval);
maxrg = L_MAX(rval, gval);
max = L_MAX(maxrg, bval);
delta = max - min;
*pvval = max;
if (delta == 0) { /* gray; no chroma */
*phval = 0;
*psval = 0;
}
else {
*psval = (l_int32)(255. * (l_float32)delta / (l_float32)max + 0.5);
if (rval == max) /* between magenta and yellow */
h = (l_float32)(gval - bval) / (l_float32)delta;
else if (gval == max) /* between yellow and cyan */
h = 2. + (l_float32)(bval - rval) / (l_float32)delta;
else /* between cyan and magenta */
h = 4. + (l_float32)(rval - gval) / (l_float32)delta;
h *= 40.0;
if (h < 0.0)
h += 240.0;
if (h >= 239.5)
h = 0.0;
*phval = (l_int32)(h + 0.5);
}
return 0;
}
/*!
* convertHSVToRGB()
*
* Input: hval, sval, vval
* &rval, &gval, &bval (<return> RGB values)
* Return: 0 if OK, 1 on error
*
* Notes:
* (1) See convertRGBToHSV() for valid input range of HSV values
* and their interpretation in color space.
*/
l_int32
convertHSVToRGB(l_int32 hval,
l_int32 sval,
l_int32 vval,
l_int32 *prval,
l_int32 *pgval,
l_int32 *pbval)
{
l_int32 i, x, y, z;
l_float32 h, f, s;
PROCNAME("convertHSVToRGB");
if (!prval || !pgval || !pbval)
return ERROR_INT("&rval, &gval, &bval not all defined", procName, 1);
if (sval == 0) { /* gray */
*prval = vval;
*pgval = vval;
*pbval = vval;
}
else {
if (hval < 0 || hval > 240)
return ERROR_INT("invalid hval", procName, 1);
if (hval == 240)
hval = 0;
h = (l_float32)hval / 40.;
i = (l_int32)h;
f = h - i;
s = (l_float32)sval / 255.;
x = (l_int32)(vval * (1. - s) + 0.5);
y = (l_int32)(vval * (1. - s * f) + 0.5);
z = (l_int32)(vval * (1. - s * (1. - f)) + 0.5);
switch (i)
{
case 0:
*prval = vval;
*pgval = z;
*pbval = x;
break;
case 1:
*prval = y;
*pgval = vval;
*pbval = x;
break;
case 2:
*prval = x;
*pgval = vval;
*pbval = z;
break;
case 3:
*prval = x;
*pgval = y;
*pbval = vval;
break;
case 4:
*prval = z;
*pgval = x;
*pbval = vval;
break;
case 5:
*prval = vval;
*pgval = x;
*pbval = y;
break;
default: /* none possible */
return 1;
}
}
return 0;
}
/*!
* pixConvertRGBToHue()
*
* Input: pixs (32 bpp RGB or 8 bpp with colormap)
* Return: pixd (8 bpp hue of HSV), or null on error
*
* Notes:
* (1) The conversion to HSV hue is in-lined here.
* (2) If there is a colormap, it is removed.
* (3) If you just want the hue component, this does it
* at about 10 Mpixels/sec/GHz, which is about
* 2x faster than using pixConvertRGBToHSV()
*/
PIX *
pixConvertRGBToHue(PIX *pixs)
{
l_int32 w, h, d, wplt, wpld;
l_int32 i, j, rval, gval, bval, hval, minrg, min, maxrg, max, delta;
l_float32 fh;
l_uint32 pixel;
l_uint32 *linet, *lined, *datat, *datad;
PIX *pixt, *pixd;
PROCNAME("pixConvertRGBToHue");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
pixGetDimensions(pixs, &w, &h, &d);
if (d != 32 && !pixGetColormap(pixs))
return (PIX *)ERROR_PTR("not cmapped or rgb", procName, NULL);
pixt = pixRemoveColormap(pixs, REMOVE_CMAP_TO_FULL_COLOR);
/* Convert RGB image */
pixd = pixCreate(w, h, 8);
pixCopyResolution(pixd, pixs);
wplt = pixGetWpl(pixt);
datat = pixGetData(pixt);
wpld = pixGetWpl(pixd);
datad = pixGetData(pixd);
for (i = 0; i < h; i++) {
linet = datat + i * wplt;
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
pixel = linet[j];
extractRGBValues(pixel, &rval, &gval, &bval);
minrg = L_MIN(rval, gval);
min = L_MIN(minrg, bval);
maxrg = L_MAX(rval, gval);
max = L_MAX(maxrg, bval);
delta = max - min;
if (delta == 0) /* gray; no chroma */
hval = 0;
else {
if (rval == max) /* between magenta and yellow */
fh = (l_float32)(gval - bval) / (l_float32)delta;
else if (gval == max) /* between yellow and cyan */
fh = 2. + (l_float32)(bval - rval) / (l_float32)delta;
else /* between cyan and magenta */
fh = 4. + (l_float32)(rval - gval) / (l_float32)delta;
fh *= 40.0;
if (fh < 0.0)
fh += 240.0;
hval = (l_int32)(fh + 0.5);
}
SET_DATA_BYTE(lined, j, hval);
}
}
pixDestroy(&pixt);
return pixd;
}
/*!
* pixConvertRGBToSaturation()
*
* Input: pixs (32 bpp RGB or 8 bpp with colormap)
* Return: pixd (8 bpp sat of HSV), or null on error
*
* Notes:
* (1) The conversion to HSV sat is in-lined here.
* (2) If there is a colormap, it is removed.
* (3) If you just want the saturation component, this does it
* at about 12 Mpixels/sec/GHz.
*/
PIX *
pixConvertRGBToSaturation(PIX *pixs)
{
l_int32 w, h, d, wplt, wpld;
l_int32 i, j, rval, gval, bval, sval, minrg, min, maxrg, max, delta;
l_uint32 pixel;
l_uint32 *linet, *lined, *datat, *datad;
PIX *pixt, *pixd;
PROCNAME("pixConvertRGBToSaturation");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
pixGetDimensions(pixs, &w, &h, &d);
if (d != 32 && !pixGetColormap(pixs))
return (PIX *)ERROR_PTR("not cmapped or rgb", procName, NULL);
pixt = pixRemoveColormap(pixs, REMOVE_CMAP_TO_FULL_COLOR);
/* Convert RGB image */
pixd = pixCreate(w, h, 8);
pixCopyResolution(pixd, pixs);
wplt = pixGetWpl(pixt);
datat = pixGetData(pixt);
wpld = pixGetWpl(pixd);
datad = pixGetData(pixd);
for (i = 0; i < h; i++) {
linet = datat + i * wplt;
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
pixel = linet[j];
extractRGBValues(pixel, &rval, &gval, &bval);
minrg = L_MIN(rval, gval);
min = L_MIN(minrg, bval);
maxrg = L_MAX(rval, gval);
max = L_MAX(maxrg, bval);
delta = max - min;
if (delta == 0) /* gray; no chroma */
sval = 0;
else
sval = (l_int32)(255. *
(l_float32)delta / (l_float32)max + 0.5);
SET_DATA_BYTE(lined, j, sval);
}
}
pixDestroy(&pixt);
return pixd;
}
/*!
* pixConvertRGBToValue()
*
* Input: pixs (32 bpp RGB or 8 bpp with colormap)
* Return: pixd (8 bpp max component intensity of HSV), or null on error
*
* Notes:
* (1) The conversion to HSV sat is in-lined here.
* (2) If there is a colormap, it is removed.
* (3) If you just want the value component, this does it
* at about 35 Mpixels/sec/GHz.
*/
PIX *
pixConvertRGBToValue(PIX *pixs)
{
l_int32 w, h, d, wplt, wpld;
l_int32 i, j, rval, gval, bval, maxrg, max;
l_uint32 pixel;
l_uint32 *linet, *lined, *datat, *datad;
PIX *pixt, *pixd;
PROCNAME("pixConvertRGBToValue");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
pixGetDimensions(pixs, &w, &h, &d);
if (d != 32 && !pixGetColormap(pixs))
return (PIX *)ERROR_PTR("not cmapped or rgb", procName, NULL);
pixt = pixRemoveColormap(pixs, REMOVE_CMAP_TO_FULL_COLOR);
/* Convert RGB image */
pixd = pixCreate(w, h, 8);
pixCopyResolution(pixd, pixs);
wplt = pixGetWpl(pixt);
datat = pixGetData(pixt);
wpld = pixGetWpl(pixd);
datad = pixGetData(pixd);
for (i = 0; i < h; i++) {
linet = datat + i * wplt;
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
pixel = linet[j];
extractRGBValues(pixel, &rval, &gval, &bval);
maxrg = L_MAX(rval, gval);
max = L_MAX(maxrg, bval);
SET_DATA_BYTE(lined, j, max);
}
}
pixDestroy(&pixt);
return pixd;
}