/*====================================================================* - Copyright (C) 2001 Leptonica. All rights reserved. - - Redistribution and use in source and binary forms, with or without - modification, are permitted provided that the following conditions - are met: - 1. Redistributions of source code must retain the above copyright - notice, this list of conditions and the following disclaimer. - 2. Redistributions in binary form must reproduce the above - copyright notice, this list of conditions and the following - disclaimer in the documentation and/or other materials - provided with the distribution. - - THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL ANY - CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, - EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, - PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR - PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY - OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING - NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS - SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. *====================================================================*/ /*! * \file quadtree.c *
 *
 *      Top level quadtree linear statistics
 *          l_int32   pixQuadtreeMean()
 *          l_int32   pixQuadtreeVariance()
 *
 *      Statistics in an arbitrary rectangle
 *          l_int32   pixMeanInRectangle()
 *          l_int32   pixVarianceInRectangle()
 *
 *      Quadtree regions
 *          BOXAA    *boxaaQuadtreeRegions()
 *
 *      Quadtree access
 *          l_int32   quadtreeGetParent()
 *          l_int32   quadtreeGetChildren()
 *          l_int32   quadtreeMaxLevels()
 *
 *      Display quadtree
 *          PIX      *fpixaDisplayQuadtree()
 *
 *
 *  There are many other statistical quantities that can be computed
 *  in a quadtree, such as rank values, and these can be added as
 *  the need arises.
 *
 *  Similar results that can approximate a single level of the quadtree
 *  can be generated by pixGetAverageTiled().  There we specify the
 *  tile size over which the mean, mean square, and root variance
 *  are generated; the results are saved in a (reduced size) pix.
 *  Because the tile dimensions are integers, it is usually not possible
 *  to obtain tilings that are a power of 2, as required for quadtrees.
 * 
*/ #ifdef HAVE_CONFIG_H #include #endif /* HAVE_CONFIG_H */ #include #include "allheaders.h" #ifndef NO_CONSOLE_IO #define DEBUG_BOXES 0 #endif /* !NO_CONSOLE_IO */ /*----------------------------------------------------------------------* * Top-level quadtree linear statistics * *----------------------------------------------------------------------*/ /*! * \brief pixQuadtreeMean() * * \param[in] pixs 8 bpp, no colormap * \param[in] nlevels in quadtree; max allowed depends on image size * \param[in] pix_ma input mean accumulator; can be null * \param[out] pfpixa mean values in quadtree * \return 0 if OK, 1 on error * *
 * Notes:
 *      (1) The returned fpixa has %nlevels of fpix, each containing
 *          the mean values at its level.  Level 0 has a
 *          single value; level 1 has 4 values; level 2 has 16; etc.
 * 
*/ l_ok pixQuadtreeMean(PIX *pixs, l_int32 nlevels, PIX *pix_ma, FPIXA **pfpixa) { l_int32 i, j, w, h, size, n; l_float32 val; BOX *box; BOXA *boxa; BOXAA *baa; FPIX *fpix; PIX *pix_mac; PROCNAME("pixQuadtreeMean"); if (!pfpixa) return ERROR_INT("&fpixa not defined", procName, 1); *pfpixa = NULL; if (!pixs || pixGetDepth(pixs) != 8) return ERROR_INT("pixs not defined or not 8 bpp", procName, 1); pixGetDimensions(pixs, &w, &h, NULL); if (nlevels > quadtreeMaxLevels(w, h)) return ERROR_INT("nlevels too large for image", procName, 1); if (!pix_ma) pix_mac = pixBlockconvAccum(pixs); else pix_mac = pixClone(pix_ma); if (!pix_mac) return ERROR_INT("pix_mac not made", procName, 1); if ((baa = boxaaQuadtreeRegions(w, h, nlevels)) == NULL) { pixDestroy(&pix_mac); return ERROR_INT("baa not made", procName, 1); } *pfpixa = fpixaCreate(nlevels); for (i = 0; i < nlevels; i++) { boxa = boxaaGetBoxa(baa, i, L_CLONE); size = 1 << i; n = boxaGetCount(boxa); /* n == size * size */ fpix = fpixCreate(size, size); for (j = 0; j < n; j++) { box = boxaGetBox(boxa, j, L_CLONE); pixMeanInRectangle(pixs, box, pix_mac, &val); fpixSetPixel(fpix, j % size, j / size, val); boxDestroy(&box); } fpixaAddFPix(*pfpixa, fpix, L_INSERT); boxaDestroy(&boxa); } pixDestroy(&pix_mac); boxaaDestroy(&baa); return 0; } /*! * \brief pixQuadtreeVariance() * * \param[in] pixs 8 bpp, no colormap * \param[in] nlevels in quadtree * \param[in] pix_ma input mean accumulator; can be null * \param[in] dpix_msa input mean square accumulator; can be null * \param[out] pfpixa_v [optional] variance values in quadtree * \param[out] pfpixa_rv [optional] root variance values in quadtree * \return 0 if OK, 1 on error * *
 * Notes:
 *      (1) The returned fpixav and fpixarv have %nlevels of fpix,
 *          each containing at the respective levels the variance
 *          and root variance values.
 * 
*/ l_ok pixQuadtreeVariance(PIX *pixs, l_int32 nlevels, PIX *pix_ma, DPIX *dpix_msa, FPIXA **pfpixa_v, FPIXA **pfpixa_rv) { l_int32 i, j, w, h, size, n; l_float32 var, rvar; BOX *box; BOXA *boxa; BOXAA *baa; FPIX *fpixv, *fpixrv; PIX *pix_mac; /* copy of mean accumulator */ DPIX *dpix_msac; /* msa clone */ PROCNAME("pixQuadtreeVariance"); if (!pfpixa_v && !pfpixa_rv) return ERROR_INT("neither &fpixav nor &fpixarv defined", procName, 1); if (pfpixa_v) *pfpixa_v = NULL; if (pfpixa_rv) *pfpixa_rv = NULL; if (!pixs || pixGetDepth(pixs) != 8) return ERROR_INT("pixs not defined or not 8 bpp", procName, 1); pixGetDimensions(pixs, &w, &h, NULL); if (nlevels > quadtreeMaxLevels(w, h)) return ERROR_INT("nlevels too large for image", procName, 1); if (!pix_ma) pix_mac = pixBlockconvAccum(pixs); else pix_mac = pixClone(pix_ma); if (!pix_mac) return ERROR_INT("pix_mac not made", procName, 1); if (!dpix_msa) dpix_msac = pixMeanSquareAccum(pixs); else dpix_msac = dpixClone(dpix_msa); if (!dpix_msac) { pixDestroy(&pix_mac); return ERROR_INT("dpix_msac not made", procName, 1); } if ((baa = boxaaQuadtreeRegions(w, h, nlevels)) == NULL) { pixDestroy(&pix_mac); dpixDestroy(&dpix_msac); return ERROR_INT("baa not made", procName, 1); } if (pfpixa_v) *pfpixa_v = fpixaCreate(nlevels); if (pfpixa_rv) *pfpixa_rv = fpixaCreate(nlevels); for (i = 0; i < nlevels; i++) { boxa = boxaaGetBoxa(baa, i, L_CLONE); size = 1 << i; n = boxaGetCount(boxa); /* n == size * size */ if (pfpixa_v) fpixv = fpixCreate(size, size); if (pfpixa_rv) fpixrv = fpixCreate(size, size); for (j = 0; j < n; j++) { box = boxaGetBox(boxa, j, L_CLONE); pixVarianceInRectangle(pixs, box, pix_mac, dpix_msac, &var, &rvar); if (pfpixa_v) fpixSetPixel(fpixv, j % size, j / size, var); if (pfpixa_rv) fpixSetPixel(fpixrv, j % size, j / size, rvar); boxDestroy(&box); } if (pfpixa_v) fpixaAddFPix(*pfpixa_v, fpixv, L_INSERT); if (pfpixa_rv) fpixaAddFPix(*pfpixa_rv, fpixrv, L_INSERT); boxaDestroy(&boxa); } pixDestroy(&pix_mac); dpixDestroy(&dpix_msac); boxaaDestroy(&baa); return 0; } /*----------------------------------------------------------------------* * Statistics in an arbitrary rectangle * *----------------------------------------------------------------------*/ /*! * \brief pixMeanInRectangle() * * \param[in] pixs 8 bpp * \param[in] box region to compute mean value * \param[in] pixma mean accumulator * \param[out] pval mean value * \return 0 if OK, 1 on error * *
 * Notes:
 *      (1) This function is intended to be used for many rectangles
 *          on the same image.  It can find the mean within a
 *          rectangle in O(1), independent of the size of the rectangle.
 * 
*/ l_ok pixMeanInRectangle(PIX *pixs, BOX *box, PIX *pixma, l_float32 *pval) { l_int32 w, h, bx, by, bw, bh; l_uint32 val00, val01, val10, val11; l_float32 norm; BOX *boxc; PROCNAME("pixMeanInRectangle"); if (!pval) return ERROR_INT("&val not defined", procName, 1); *pval = 0.0; if (!pixs || pixGetDepth(pixs) != 8) return ERROR_INT("pixs not defined", procName, 1); if (!box) return ERROR_INT("box not defined", procName, 1); if (!pixma) return ERROR_INT("pixma not defined", procName, 1); /* Clip rectangle to image */ pixGetDimensions(pixs, &w, &h, NULL); boxc = boxClipToRectangle(box, w, h); boxGetGeometry(boxc, &bx, &by, &bw, &bh); boxDestroy(&boxc); if (bw == 0 || bh == 0) return ERROR_INT("no pixels in box", procName, 1); /* Use up to 4 points in the accumulator */ norm = 1.0 / ((l_float32)(bw) * bh); if (bx > 0 && by > 0) { pixGetPixel(pixma, bx + bw - 1, by + bh - 1, &val11); pixGetPixel(pixma, bx + bw - 1, by - 1, &val10); pixGetPixel(pixma, bx - 1, by + bh - 1, &val01); pixGetPixel(pixma, bx - 1, by - 1, &val00); *pval = norm * (val11 - val01 + val00 - val10); } else if (by > 0) { /* bx == 0 */ pixGetPixel(pixma, bw - 1, by + bh - 1, &val11); pixGetPixel(pixma, bw - 1, by - 1, &val10); *pval = norm * (val11 - val10); } else if (bx > 0) { /* by == 0 */ pixGetPixel(pixma, bx + bw - 1, bh - 1, &val11); pixGetPixel(pixma, bx - 1, bh - 1, &val01); *pval = norm * (val11 - val01); } else { /* bx == 0 && by == 0 */ pixGetPixel(pixma, bw - 1, bh - 1, &val11); *pval = norm * val11; } return 0; } /*! * \brief pixVarianceInRectangle() * * \param[in] pixs 8 bpp * \param[in] box region to compute variance and/or root variance * \param[in] pix_ma mean accumulator * \param[in] dpix_msa mean square accumulator * \param[out] pvar [optional] variance * \param[out] prvar [optional] root variance * \return 0 if OK, 1 on error * *
 * Notes:
 *      (1) This function is intended to be used for many rectangles
 *          on the same image.  It can find the variance and/or the
 *          square root of the variance within a rectangle in O(1),
 *          independent of the size of the rectangle.
 * 
*/ l_ok pixVarianceInRectangle(PIX *pixs, BOX *box, PIX *pix_ma, DPIX *dpix_msa, l_float32 *pvar, l_float32 *prvar) { l_int32 w, h, bx, by, bw, bh; l_uint32 val00, val01, val10, val11; l_float64 dval00, dval01, dval10, dval11, mval, msval, var, norm; BOX *boxc; PROCNAME("pixVarianceInRectangle"); if (!pvar && !prvar) return ERROR_INT("neither &var nor &rvar defined", procName, 1); if (pvar) *pvar = 0.0; if (prvar) *prvar = 0.0; if (!pixs || pixGetDepth(pixs) != 8) return ERROR_INT("pixs not defined", procName, 1); if (!box) return ERROR_INT("box not defined", procName, 1); if (!pix_ma) return ERROR_INT("pix_ma not defined", procName, 1); if (!dpix_msa) return ERROR_INT("dpix_msa not defined", procName, 1); /* Clip rectangle to image */ pixGetDimensions(pixs, &w, &h, NULL); boxc = boxClipToRectangle(box, w, h); boxGetGeometry(boxc, &bx, &by, &bw, &bh); boxDestroy(&boxc); if (bw == 0 || bh == 0) return ERROR_INT("no pixels in box", procName, 1); /* Use up to 4 points in the accumulators */ norm = 1.0 / ((l_float32)(bw) * bh); if (bx > 0 && by > 0) { pixGetPixel(pix_ma, bx + bw - 1, by + bh - 1, &val11); pixGetPixel(pix_ma, bx + bw - 1, by - 1, &val10); pixGetPixel(pix_ma, bx - 1, by + bh - 1, &val01); pixGetPixel(pix_ma, bx - 1, by - 1, &val00); dpixGetPixel(dpix_msa, bx + bw - 1, by + bh - 1, &dval11); dpixGetPixel(dpix_msa, bx + bw - 1, by - 1, &dval10); dpixGetPixel(dpix_msa, bx - 1, by + bh - 1, &dval01); dpixGetPixel(dpix_msa, bx - 1, by - 1, &dval00); mval = norm * (val11 - val01 + val00 - val10); msval = norm * (dval11 - dval01 + dval00 - dval10); var = (msval - mval * mval); if (pvar) *pvar = (l_float32)var; if (prvar) *prvar = (l_float32)(sqrt(var)); } else if (by > 0) { /* bx == 0 */ pixGetPixel(pix_ma, bw - 1, by + bh - 1, &val11); pixGetPixel(pix_ma, bw - 1, by - 1, &val10); dpixGetPixel(dpix_msa, bw - 1, by + bh - 1, &dval11); dpixGetPixel(dpix_msa, bw - 1, by - 1, &dval10); mval = norm * (val11 - val10); msval = norm * (dval11 - dval10); var = (msval - mval * mval); if (pvar) *pvar = (l_float32)var; if (prvar) *prvar = (l_float32)(sqrt(var)); } else if (bx > 0) { /* by == 0 */ pixGetPixel(pix_ma, bx + bw - 1, bh - 1, &val11); pixGetPixel(pix_ma, bx - 1, bh - 1, &val01); dpixGetPixel(dpix_msa, bx + bw - 1, bh - 1, &dval11); dpixGetPixel(dpix_msa, bx - 1, bh - 1, &dval01); mval = norm * (val11 - val01); msval = norm * (dval11 - dval01); var = (msval - mval * mval); if (pvar) *pvar = (l_float32)var; if (prvar) *prvar = (l_float32)(sqrt(var)); } else { /* bx == 0 && by == 0 */ pixGetPixel(pix_ma, bw - 1, bh - 1, &val11); dpixGetPixel(dpix_msa, bw - 1, bh - 1, &dval11); mval = norm * val11; msval = norm * dval11; var = (msval - mval * mval); if (pvar) *pvar = (l_float32)var; if (prvar) *prvar = (l_float32)(sqrt(var)); } return 0; } /*----------------------------------------------------------------------* * Quadtree regions * *----------------------------------------------------------------------*/ /*! * \brief boxaaQuadtreeRegions() * * \param[in] w, h size of pix that is being quadtree-ized * \param[in] nlevels number of levels in quadtree * \return baa for quadtree regions at each level, or NULL on error * *
 * Notes:
 *      (1) The returned boxaa has %nlevels of boxa, each containing
 *          the set of rectangles at that level.  The rectangle at
 *          level 0 is the entire region; at level 1 the region is
 *          divided into 4 rectangles, and at level n there are n^4
 *          rectangles.
 *      (2) At each level, the rectangles in the boxa are in "raster"
 *          order, with LR (fast scan) and TB (slow scan).
 * 
*/ BOXAA * boxaaQuadtreeRegions(l_int32 w, l_int32 h, l_int32 nlevels) { l_int32 i, j, k, maxpts, nside, nbox, bw, bh; l_int32 *xstart, *xend, *ystart, *yend; BOX *box; BOXA *boxa; BOXAA *baa; PROCNAME("boxaaQuadtreeRegions"); if (nlevels < 1) return (BOXAA *)ERROR_PTR("nlevels must be >= 1", procName, NULL); if (w < (1 << (nlevels - 1))) return (BOXAA *)ERROR_PTR("w doesn't support nlevels", procName, NULL); if (h < (1 << (nlevels - 1))) return (BOXAA *)ERROR_PTR("h doesn't support nlevels", procName, NULL); baa = boxaaCreate(nlevels); maxpts = 1 << (nlevels - 1); xstart = (l_int32 *)LEPT_CALLOC(maxpts, sizeof(l_int32)); xend = (l_int32 *)LEPT_CALLOC(maxpts, sizeof(l_int32)); ystart = (l_int32 *)LEPT_CALLOC(maxpts, sizeof(l_int32)); yend = (l_int32 *)LEPT_CALLOC(maxpts, sizeof(l_int32)); for (k = 0; k < nlevels; k++) { nside = 1 << k; /* number of boxes in each direction */ for (i = 0; i < nside; i++) { xstart[i] = (w - 1) * i / nside; if (i > 0) xstart[i]++; xend[i] = (w - 1) * (i + 1) / nside; ystart[i] = (h - 1) * i / nside; if (i > 0) ystart[i]++; yend[i] = (h - 1) * (i + 1) / nside; #if DEBUG_BOXES lept_stderr( "k = %d, xs[%d] = %d, xe[%d] = %d, ys[%d] = %d, ye[%d] = %d\n", k, i, xstart[i], i, xend[i], i, ystart[i], i, yend[i]); #endif /* DEBUG_BOXES */ } nbox = 1 << (2 * k); boxa = boxaCreate(nbox); for (i = 0; i < nside; i++) { bh = yend[i] - ystart[i] + 1; for (j = 0; j < nside; j++) { bw = xend[j] - xstart[j] + 1; box = boxCreate(xstart[j], ystart[i], bw, bh); boxaAddBox(boxa, box, L_INSERT); } } boxaaAddBoxa(baa, boxa, L_INSERT); } LEPT_FREE(xstart); LEPT_FREE(xend); LEPT_FREE(ystart); LEPT_FREE(yend); return baa; } /*----------------------------------------------------------------------* * Quadtree access * *----------------------------------------------------------------------*/ /*! * \brief quadtreeGetParent() * * \param[in] fpixa mean, variance or root variance * \param[in] level, x, y of current pixel * \param[out] pval parent pixel value, or 0.0 on error * \return 0 if OK, 1 on error * *
 * Notes:
 *      (1) Check return value for error.  On error, val is returned as 0.0.
 *      (2) The parent is located at:
 *             level - 1
 *             (x/2, y/2)
 * 
*/ l_ok quadtreeGetParent(FPIXA *fpixa, l_int32 level, l_int32 x, l_int32 y, l_float32 *pval) { l_int32 n; PROCNAME("quadtreeGetParent"); if (!pval) return ERROR_INT("&val not defined", procName, 1); *pval = 0.0; if (!fpixa) return ERROR_INT("fpixa not defined", procName, 1); n = fpixaGetCount(fpixa); if (level < 1 || level >= n) return ERROR_INT("invalid level", procName, 1); if (fpixaGetPixel(fpixa, level - 1, x / 2, y / 2, pval) != 0) return ERROR_INT("invalid coordinates", procName, 1); return 0; } /*! * \brief quadtreeGetChildren() * * \param[in] fpixa mean, variance or root variance * \param[in] level, x, y of current pixel * \param[out] pval00, pval01, * pval10, pval11 four child pixel values * \return 0 if OK, 1 on error * *
 * Notes:
 *      (1) Check return value for error.  On error, all return vals are 0.0.
 *      (2) The returned child pixels are located at:
 *             level + 1
 *             (2x, 2y), (2x+1, 2y), (2x, 2y+1), (2x+1, 2y+1)
 * 
*/ l_ok quadtreeGetChildren(FPIXA *fpixa, l_int32 level, l_int32 x, l_int32 y, l_float32 *pval00, l_float32 *pval10, l_float32 *pval01, l_float32 *pval11) { l_int32 n; PROCNAME("quadtreeGetChildren"); if (!pval00 || !pval01 || !pval10 || !pval11) return ERROR_INT("&val* not all defined", procName, 1); *pval00 = *pval10 = *pval01 = *pval11 = 0.0; if (!fpixa) return ERROR_INT("fpixa not defined", procName, 1); n = fpixaGetCount(fpixa); if (level < 0 || level >= n - 1) return ERROR_INT("invalid level", procName, 1); if (fpixaGetPixel(fpixa, level + 1, 2 * x, 2 * y, pval00) != 0) return ERROR_INT("invalid coordinates", procName, 1); fpixaGetPixel(fpixa, level + 1, 2 * x + 1, 2 * y, pval10); fpixaGetPixel(fpixa, level + 1, 2 * x, 2 * y + 1, pval01); fpixaGetPixel(fpixa, level + 1, 2 * x + 1, 2 * y + 1, pval11); return 0; } /*! * \brief quadtreeMaxLevels() * * \param[in] w, h dimensions of image * \return maxlevels maximum number of levels allowed, or -1 on error * *
 * Notes:
 *      (1) The criterion for maxlevels is that the subdivision not
 *          go down below the single pixel level.  The 1.5 factor
 *          is intended to keep any rectangle from accidentally
 *          having zero dimension due to integer truncation.
 * 
*/ l_int32 quadtreeMaxLevels(l_int32 w, l_int32 h) { l_int32 i, minside; minside = L_MIN(w, h); for (i = 0; i < 20; i++) { /* 2^10 = one million */ if (minside < (1.5 * (1 << i))) return i - 1; } return -1; /* fail if the image has over a trillion pixels! */ } /*----------------------------------------------------------------------* * Display quadtree * *----------------------------------------------------------------------*/ /*! * \brief fpixaDisplayQuadtree() * * \param[in] fpixa mean, variance or root variance * \param[in] factor replication factor at lowest level * \param[in] fontsize 4, ... 20 * \return pixd 8 bpp, mosaic of quadtree images, or NULL on error * *
 * Notes:
 *      (1) The mean and root variance fall naturally in the 8 bpp range,
 *          but the variance is typically outside the range.  This
 *          function displays 8 bpp pix clipped to 255, so the image
 *          pixels will mostly be 255 (white).
 * 
*/ PIX * fpixaDisplayQuadtree(FPIXA *fpixa, l_int32 factor, l_int32 fontsize) { char buf[256]; l_int32 nlevels, i, mag, w; L_BMF *bmf; FPIX *fpix; PIX *pixt1, *pixt2, *pixt3, *pixt4, *pixd; PIXA *pixat; PROCNAME("fpixaDisplayQuadtree"); if (!fpixa) return (PIX *)ERROR_PTR("fpixa not defined", procName, NULL); if ((nlevels = fpixaGetCount(fpixa)) == 0) return (PIX *)ERROR_PTR("pixas empty", procName, NULL); if ((bmf = bmfCreate(NULL, fontsize)) == NULL) L_ERROR("bmf not made; text will not be added", procName); pixat = pixaCreate(nlevels); for (i = 0; i < nlevels; i++) { fpix = fpixaGetFPix(fpixa, i, L_CLONE); pixt1 = fpixConvertToPix(fpix, 8, L_CLIP_TO_ZERO, 0); mag = factor * (1 << (nlevels - i - 1)); pixt2 = pixExpandReplicate(pixt1, mag); pixt3 = pixConvertTo32(pixt2); snprintf(buf, sizeof(buf), "Level %d\n", i); pixt4 = pixAddSingleTextblock(pixt3, bmf, buf, 0xff000000, L_ADD_BELOW, NULL); pixaAddPix(pixat, pixt4, L_INSERT); fpixDestroy(&fpix); pixDestroy(&pixt1); pixDestroy(&pixt2); pixDestroy(&pixt3); } w = pixGetWidth(pixt4); pixd = pixaDisplayTiledInRows(pixat, 32, nlevels * (w + 80), 1.0, 0, 30, 2); pixaDestroy(&pixat); bmfDestroy(&bmf); return pixd; }