Файл src/pix3.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "allheaders.h"

Макросы

#define EQUAL_SIZE_WARNING   0

Функции

static l_int32 findTilePatchCenter (PIX *pixs, BOX *box, l_int32 dir, l_uint32 targdist, l_uint32 *pdist, l_int32 *pxc, l_int32 *pyc)
l_int32 pixSetMasked (PIX *pixd, PIX *pixm, l_uint32 val)
l_int32 pixSetMaskedGeneral (PIX *pixd, PIX *pixm, l_uint32 val, l_int32 x, l_int32 y)
l_int32 pixCombineMasked (PIX *pixd, PIX *pixs, PIX *pixm)
l_int32 pixCombineMaskedGeneral (PIX *pixd, PIX *pixs, PIX *pixm, l_int32 x, l_int32 y)
l_int32 pixPaintThroughMask (PIX *pixd, PIX *pixm, l_int32 x, l_int32 y, l_uint32 val)
l_int32 pixPaintSelfThroughMask (PIX *pixd, PIX *pixm, l_int32 x, l_int32 y, l_int32 tilesize, l_int32 searchdir)
PIXpixInvert (PIX *pixd, PIX *pixs)
PIXpixOr (PIX *pixd, PIX *pixs1, PIX *pixs2)
PIXpixAnd (PIX *pixd, PIX *pixs1, PIX *pixs2)
PIXpixXor (PIX *pixd, PIX *pixs1, PIX *pixs2)
PIXpixSubtract (PIX *pixd, PIX *pixs1, PIX *pixs2)
l_int32 pixZero (PIX *pix, l_int32 *pempty)
l_int32 pixCountPixels (PIX *pix, l_int32 *pcount, l_int32 *tab8)
NUMApixaCountPixels (PIXA *pixa)
l_int32 pixCountPixelsInRow (PIX *pix, l_int32 row, l_int32 *pcount, l_int32 *tab8)
NUMApixCountPixelsByRow (PIX *pix, l_int32 *tab8)
l_int32 pixThresholdPixels (PIX *pix, l_int32 thresh, l_int32 *pabove, l_int32 *tab8)
l_int32makePixelSumTab8 (void)
l_int32makePixelCentroidTab8 (void)
l_int32 pixSumPixelValues (PIX *pix, BOX *box, l_float64 *psum)
PIXpixMirroredTiling (PIX *pixs, l_int32 w, l_int32 h)

Макросы

#define EQUAL_SIZE_WARNING   0


Функции

static l_int32 findTilePatchCenter ( PIX pixs,
BOX box,
l_int32  searchdir,
l_uint32  targdist,
l_uint32 pdist,
l_int32 pxc,
l_int32 pyc 
) [static]

findTilePatchCenter()

Input: pixs (8 or 16 bpp; distance function of a binary mask) box (region of pixs to search around) searchdir (L_HORIZ or L_VERT; direction to search) targdist (desired distance of selected patch center from fg) &dist (<return> actual distance of selected location) &xc, &yc (<return> location of selected patch center) Return: 0 if OK, 1 on error

Notes: (1) This looks for a patch of non-masked image, that is outside but near the input box. The input pixs is a distance function giving the distance from the fg in a binary mask. (2) The target distance implicitly specifies a desired size for the patch. The location of the center of the patch, and the actual distance from fg are returned. (3) If the target distance is larger than 255, a 16-bit distance transform is input. (4) It is assured that a square centered at (xc, yc) and of size 'dist' will not intersect with the fg of the binary mask that was used to generate pixs.

l_int32* makePixelCentroidTab8 ( void   ) 

makePixelCentroidTab8()

Input: void Return: table of 256 l_int32, or null on error

Notes: (1) This table of integers gives the centroid weight of the 1 bits in the 8 bit index. In other words, if sumtab is obtained by makePixelSumTab8, and centroidtab is obtained by makePixelCentroidTab8, then, for 1 <= i <= 255, centroidtab[i] / (float)sumtab[i] is the centroid of the 1 bits in the 8-bit index i, where the MSB is considered to have position 0 and the LSB is considered to have position 7.

l_int32* makePixelSumTab8 ( void   ) 

makePixelSumTab8()

Input: void Return: table of 256 l_int32, or null on error

Notes: (1) This table of integers gives the number of 1 bits in the 8 bit index.

NUMA* pixaCountPixels ( PIXA pixa  ) 

pixaCountPixels()

Input: pixa (array of binary pix) Return: na of ON pixels in each pix, or null on error

PIX* pixAnd ( PIX pixd,
PIX pixs1,
PIX pixs2 
)

pixAnd()

Input: pixd (<optional>; this can be null, equal to pixs1, different from pixs1) pixs1 (can be == pixd) pixs2 (must be != pixd) Return: pixd always

Notes: (1) This gives the intersection of two images with equal depth, aligning them to the the UL corner. pixs1 and pixs2 need not have the same width and height. (2) There are 3 cases: (a) pixd == null, (src1 & src2) --> new pixd (b) pixd == pixs1, (src1 & src2) --> src1 (in-place) (c) pixd != pixs1, (src1 & src2) --> input pixd (3) For clarity, if the case is known, use these patterns: (a) pixd = pixAnd(NULL, pixs1, pixs2); (b) pixAnd(pixs1, pixs1, pixs2); (c) pixAnd(pixd, pixs1, pixs2); (4) The size of the result is determined by pixs1. (5) The depths of pixs1 and pixs2 must be equal. (6) Note carefully that the order of pixs1 and pixs2 only matters for the in-place case. For in-place, you must have pixd == pixs1. Setting pixd == pixs2 gives an incorrect result: the copy puts pixs1 image data in pixs2, and the rasterop is then between pixs2 and pixs2 (a no-op).

l_int32 pixCombineMasked ( PIX pixd,
PIX pixs,
PIX pixm 
)

pixCombineMasked()

Input: pixd (1 bpp, 8 bpp gray or 32 bpp rgb; no cmap) pixs (1 bpp, 8 bpp gray or 32 bpp rgb; no cmap) pixm (<optional> 1 bpp mask; no operation if NULL) Return: 0 if OK; 1 on error

Notes: (1) In-place operation; pixd is changed. (2) This sets each pixel in pixd that co-locates with an ON pixel in pixm to the corresponding value of pixs. (3) pixs and pixd must be the same depth and not colormapped. (4) All three input pix are aligned at the UL corner, and the operation is clipped to the intersection of all three images. (5) If pixm == NULL, it's a no-op. (6) Implementation: see notes in pixCombineMaskedGeneral(). For 8 bpp selective masking, you might guess that it would be faster to generate an 8 bpp version of pixm, using pixConvert1To8(pixm, 0, 255), and then use a general combine operation d = (d & ~m) | (s & m) on a word-by-word basis. Not always. The word-by-word combine takes a time that is independent of the mask data. If the mask is relatively sparse, the byte-check method is actually faster!

l_int32 pixCombineMaskedGeneral ( PIX pixd,
PIX pixs,
PIX pixm,
l_int32  x,
l_int32  y 
)

pixCombineMaskedGeneral()

Input: pixd (1 bpp, 8 bpp gray or 32 bpp rgb) pixs (1 bpp, 8 bpp gray or 32 bpp rgb) pixm (<optional> 1 bpp mask) x, y (origin of pixs and pixm relative to pixd; can be negative) Return: 0 if OK; 1 on error

Notes: (1) In-place operation; pixd is changed. (2) This is a generalized version of pixCombinedMasked(), where the source and mask can be placed at the same (arbitrary) location relative to pixd. (3) pixs and pixd must be the same depth and not colormapped. (4) The UL corners of both pixs and pixm are aligned with the point (x, y) of pixd, and the operation is clipped to the intersection of all three images. (5) If pixm == NULL, it's a no-op. (6) Implementation. There are two ways to do these. In the first, we use rasterop, ORing the part of pixs under the mask with pixd (which has been appropriately cleared there first). In the second, the mask is used one pixel at a time to selectively replace pixels of pixd with those of pixs. Here, we use rasterop for 1 bpp and pixel-wise replacement for 8 and 32 bpp. To use rasterop for 8 bpp, for example, we must first generate an 8 bpp version of the mask. The code is simple:

Pix *pixm8 = pixConvert1To8(NULL, pixm, 0, 255); Pix *pixt = pixAnd(NULL, pixs, pixm8); pixRasterop(pixd, x, y, wmin, hmin, PIX_DST & PIX_NOT(PIX_SRC), pixm8, 0, 0); pixRasterop(pixd, x, y, wmin, hmin, PIX_SRC | PIX_DST, pixt, 0, 0); pixDestroy(&pixt); pixDestroy(&pixm8);

l_int32 pixCountPixels ( PIX pix,
l_int32 pcount,
l_int32 tab8 
)

pixCountPixels()

Input: binary pix &count (<return> count of ON pixels) tab8 (<optional> 8-bit pixel lookup table) Return: 0 if OK; 1 on error

NUMA* pixCountPixelsByRow ( PIX pix,
l_int32 tab8 
)

pixCountPixelsByRow()

Input: binary pix tab8 (<optional> 8-bit pixel lookup table) Return: na of counts, or null on error

l_int32 pixCountPixelsInRow ( PIX pix,
l_int32  row,
l_int32 pcount,
l_int32 tab8 
)

pixCountPixelsInRow()

Input: binary pix row number &count (<return> sum of ON pixels in raster line) tab8 (<optional> 8-bit pixel lookup table) Return: 0 if OK; 1 on error

PIX* pixInvert ( PIX pixd,
PIX pixs 
)

pixInvert()

Input: pixd (<optional>; this can be null, equal to pixs, or different from pixs) pixs Return: pixd, or null on error

Notes: (1) This inverts pixs, for all pixel depths. (2) There are 3 cases: (a) pixd == null, ~src --> new pixd (b) pixd == pixs, ~src --> src (in-place) (c) pixd != pixs, ~src --> input pixd (3) For clarity, if the case is known, use these patterns: (a) pixd = pixInvert(NULL, pixs); (b) pixInvert(pixs, pixs); (c) pixInvert(pixd, pixs);

PIX* pixMirroredTiling ( PIX pixs,
l_int32  w,
l_int32  h 
)

pixMirroredTiling()

Input: pixs (8 or 32 bpp, small tile; to be replicated) w, h (dimensions of output pix) Return: pixd (usually larger pix, mirror-tiled with pixs), or null on error

Notes: (1) This uses mirrored tiling, where each row alternates with LR flips and every column alternates with TB flips, such that the result is a tiling with identical 2 x 2 tiles, each of which is composed of these transforms: ----------------- | 1 | LR | ----------------- | TB | LR/TB | -----------------

PIX* pixOr ( PIX pixd,
PIX pixs1,
PIX pixs2 
)

pixOr()

Input: pixd (<optional>; this can be null, equal to pixs1, different from pixs1) pixs1 (can be == pixd) pixs2 (must be != pixd) Return: pixd always

Notes: (1) This gives the union of two images with equal depth, aligning them to the the UL corner. pixs1 and pixs2 need not have the same width and height. (2) There are 3 cases: (a) pixd == null, (src1 | src2) --> new pixd (b) pixd == pixs1, (src1 | src2) --> src1 (in-place) (c) pixd != pixs1, (src1 | src2) --> input pixd (3) For clarity, if the case is known, use these patterns: (a) pixd = pixOr(NULL, pixs1, pixs2); (b) pixOr(pixs1, pixs1, pixs2); (c) pixOr(pixd, pixs1, pixs2); (4) The size of the result is determined by pixs1. (5) The depths of pixs1 and pixs2 must be equal. (6) Note carefully that the order of pixs1 and pixs2 only matters for the in-place case. For in-place, you must have pixd == pixs1. Setting pixd == pixs2 gives an incorrect result: the copy puts pixs1 image data in pixs2, and the rasterop is then between pixs2 and pixs2 (a no-op).

l_int32 pixPaintSelfThroughMask ( PIX pixd,
PIX pixm,
l_int32  x,
l_int32  y,
l_int32  tilesize,
l_int32  searchdir 
)

pixPaintSelfThroughMask()

Input: pixd (8 bpp gray or 32 bpp rgb; not colormapped) pixm (1 bpp mask) x, y (origin of pixm relative to pixd; must not be negative) tilesize (requested size for tiling) searchdir (L_HORIZ, L_VERT) Return: 0 if OK; 1 on error

Notes: (1) In-place operation; pixd is changed. (2) If pixm == NULL, it's a no-op. (3) The mask origin is placed at (x,y) on pixd, and the operation is clipped to the intersection of pixd and the fg of the mask. (4) The tilesize is the the requested size for tiling. The actual size for each c.c. will be bounded by the minimum dimension of the c.c. and the distance at which the tile center is located. (5) searchdir is the direction with respect to the b.b. of each mask component, from which the square patch is chosen and tiled onto the image, clipped by the mask component. (6) Specifically, a mirrored tiling, generated from pixd, is used to construct the pixels that are painted onto pixd through pixm.

l_int32 pixPaintThroughMask ( PIX pixd,
PIX pixm,
l_int32  x,
l_int32  y,
l_uint32  val 
)

pixPaintThroughMask()

Input: pixd (1, 2, 4, 8, 16 or 32 bpp; or colormapped) pixm (<optional> 1 bpp mask) x, y (origin of pixm relative to pixd; can be negative) val (pixel value to set at each masked pixel) Return: 0 if OK; 1 on error

Notes: (1) In-place operation. Calls pixSetMaskedCmap() for colormapped images. (2) For 1, 2, 4, 8 and 16 bpp gray, we take the appropriate number of least significant bits of val. (3) If pixm == NULL, it's a no-op. (4) The mask origin is placed at (x,y) on pixd, and the operation is clipped to the intersection of rectangles. (5) For rgb, the components in val are in the canonical locations, with red in location COLOR_RED, etc. (6) Implementation detail 1: For painting with val == 0 or val == maxval, you can use rasterop. If val == 0, invert the mask so that it's 0 over the region into which you want to write, and use PIX_SRC & PIX_DST to clear those pixels. To write with val = maxval (all 1's), use PIX_SRC | PIX_DST to set all bits under the mask. (7) Implementation detail 2: The rasterop trick can be used for depth > 1 as well. For val == 0, generate the mask for depth d from the binary mask using pixmd = pixUnpackBinary(pixm, d, 1); and use pixRasterop() with PIX_MASK. For val == maxval, pixmd = pixUnpackBinary(pixm, d, 0); and use pixRasterop() with PIX_PAINT. But note that if d == 32 bpp, it is about 3x faster to use the general implementation (not pixRasterop()). (8) Implementation detail 3: It might be expected that the switch in the inner loop will cause large branching delays and should be avoided. This is not the case, because the entrance is always the same and the compiler can correctly predict the jump.

l_int32 pixSetMasked ( PIX pixd,
PIX pixm,
l_uint32  val 
)

pixSetMasked()

Input: pixd (1, 2, 4, 8, 16 or 32 bpp; or colormapped) pixm (<optional> 1 bpp mask; no operation if NULL) val (value to set at each masked pixel) Return: 0 if OK; 1 on error

Notes: (1) In-place operation. Calls pixSetMaskedCmap() for colormapped images. (2) If pixm == NULL, a warning is given. (3) It is an implicitly aligned operation, where the UL corners of pixd and pixm coincide. A warning is issued if the two image sizes differ significantly, but the operation proceeds. (4) Each pixel in pixd that co-locates with an ON pixel in pixm is set to the specified input value. Other pixels in pixd are not changed. (5) You can visualize this as painting the color through the mask, as a stencil. (6) If you do not want to have the UL corners aligned, use the function pixSetMaskedGeneral(), which requires you to input the UL corner of pixm relative to pixd. (7) Implementation details: see comments in pixPaintThroughMask() for when we use rasterop to do the painting.

l_int32 pixSetMaskedGeneral ( PIX pixd,
PIX pixm,
l_uint32  val,
l_int32  x,
l_int32  y 
)

pixSetMaskedGeneral()

Input: pixd (8, 16 or 32 bpp) pixm (<optional> 1 bpp mask; no operation if null) val (value to set at each masked pixel) x, y (location of UL corner of pixm relative to pixd; can be negative) Return: 0 if OK; 1 on error

Notes: (1) This is an in-place operation. (2) Alignment is explicit. If you want the UL corners of the two images to be aligned, use pixSetMasked(). (3) A typical use would be painting through the foreground of a small binary mask pixm, located somewhere on a larger pixd. Other pixels in pixd are not changed. (4) You can visualize this as painting the color through the mask, as a stencil. (5) This uses rasterop to handle clipping and different depths of pixd. (6) If pixd has a colormap, you should call pixPaintThroughMask(). (7) Why is this function here, if pixPaintThroughMask() does the same thing, and does it more generally? I've retained it here to show how one can paint through a mask using only full image rasterops, rather than pixel peeking in pixm and poking in pixd. It's somewhat baroque, but I found it amusing.

PIX* pixSubtract ( PIX pixd,
PIX pixs1,
PIX pixs2 
)

pixSubtract()

Input: pixd (<optional>; this can be null, equal to pixs1, equal to pixs2, or different from both pixs1 and pixs2) pixs1 (can be == pixd) pixs2 (can be == pixd) Return: pixd always

Notes: (1) This gives the set subtraction of two images with equal depth, aligning them to the the UL corner. pixs1 and pixs2 need not have the same width and height. (2) Source pixs2 is always subtracted from source pixs1. The result is pixs1 \ pixs2 = pixs1 & (~pixs2) (3) There are 4 cases: (a) pixd == null, (src1 - src2) --> new pixd (b) pixd == pixs1, (src1 - src2) --> src1 (in-place) (c) pixd == pixs2, (src1 - src2) --> src2 (in-place) (d) pixd != pixs1 && pixd != pixs2), (src1 - src2) --> input pixd (4) For clarity, if the case is known, use these patterns: (a) pixd = pixSubtract(NULL, pixs1, pixs2); (b) pixSubtract(pixs1, pixs1, pixs2); (c) pixSubtract(pixs2, pixs1, pixs2); (d) pixSubtract(pixd, pixs1, pixs2); (5) The size of the result is determined by pixs1. (6) The depths of pixs1 and pixs2 must be equal.

l_int32 pixSumPixelValues ( PIX pix,
BOX box,
l_float64 psum 
)

pixSumPixelValues()

Input: pix (1, 2, 4, 8, 16, 32 bpp; not cmapped) box (<optional> if null, use entire image) &sum (<return> sum of pixel values in region) Return: 0 if OK; 1 on error

l_int32 pixThresholdPixels ( PIX pix,
l_int32  thresh,
l_int32 pabove,
l_int32 tab8 
)

pixThresholdPixels()

Input: binary pix threshold &above (<return> 1 if above threshold; 0 if equal to or less than threshold) tab8 (<optional> 8-bit pixel lookup table) Return: 0 if OK; 1 on error

Notes: (1) This sums the ON pixels and returns immediately if the count goes above threshold. It is therefore more efficient for matching images (by running this function on the xor of the 2 images) than using pixCountPixels(), which counts all pixels before returning.

PIX* pixXor ( PIX pixd,
PIX pixs1,
PIX pixs2 
)

pixXor()

Input: pixd (<optional>; this can be null, equal to pixs1, different from pixs1) pixs1 (can be == pixd) pixs2 (must be != pixd) Return: pixd always

Notes: (1) This gives the XOR of two images with equal depth, aligning them to the the UL corner. pixs1 and pixs2 need not have the same width and height. (2) There are 3 cases: (a) pixd == null, (src1 ^ src2) --> new pixd (b) pixd == pixs1, (src1 ^ src2) --> src1 (in-place) (c) pixd != pixs1, (src1 ^ src2) --> input pixd (3) For clarity, if the case is known, use these patterns: (a) pixd = pixXor(NULL, pixs1, pixs2); (b) pixXor(pixs1, pixs1, pixs2); (c) pixXor(pixd, pixs1, pixs2); (4) The size of the result is determined by pixs1. (5) The depths of pixs1 and pixs2 must be equal. (6) Note carefully that the order of pixs1 and pixs2 only matters for the in-place case. For in-place, you must have pixd == pixs1. Setting pixd == pixs2 gives an incorrect result: the copy puts pixs1 image data in pixs2, and the rasterop is then between pixs2 and pixs2 (a no-op).

l_int32 pixZero ( PIX pix,
l_int32 pempty 
)

pixZero()

Input: pix &empty (<return> 1 if all bits in image are 0; 0 otherwise) Return: 0 if OK; 1 on error

Notes: (1) For a binary image, if there are no fg (black) pixels, empty = 1. (2) For a grayscale image, if all pixels are black (0), empty = 1. (3) For an RGB image, if all 4 components in every pixel is 0, empty = 1.


Документация по Leptonica. Последние изменения: Fri Aug 7 20:31:38 2009. Создано системой  doxygen 1.5.9