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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:24:48 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:24:48 +0000 |
commit | cca66b9ec4e494c1d919bff0f71a820d8afab1fa (patch) | |
tree | 146f39ded1c938019e1ed42d30923c2ac9e86789 /src/3rdparty/autotrace/despeckle.c | |
parent | Initial commit. (diff) | |
download | inkscape-cca66b9ec4e494c1d919bff0f71a820d8afab1fa.tar.xz inkscape-cca66b9ec4e494c1d919bff0f71a820d8afab1fa.zip |
Adding upstream version 1.2.2.upstream/1.2.2upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | src/3rdparty/autotrace/despeckle.c | 710 |
1 files changed, 710 insertions, 0 deletions
diff --git a/src/3rdparty/autotrace/despeckle.c b/src/3rdparty/autotrace/despeckle.c new file mode 100644 index 0000000..3ab66ac --- /dev/null +++ b/src/3rdparty/autotrace/despeckle.c @@ -0,0 +1,710 @@ +/* despeckle.c: Bitmap despeckler + + Copyright (C) 2001 David A. Bartold / Martin Weber + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public License + as published by the Free Software Foundation; either version 2.1 of + the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 + USA. */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif /* Def: HAVE_CONFIG_H */ + +#include <assert.h> +#include <math.h> +#include <stdio.h> +#include <time.h> +#include "xstd.h" +#include "logreport.h" +#include "types.h" +#include "bitmap.h" +#include "despeckle.h" + +/* Calculate Error - compute the error between two colors + * + * Input parameters: + * Two 24 bit RGB colors + * + * Returns: + * The squared error between the two colors + */ + +static int calc_error(unsigned char *color1, unsigned char *color2) +{ + int the_error; + int temp; + + temp = color1[0] - color2[0]; + the_error = temp * temp; + temp = color1[1] - color2[1]; + the_error += temp * temp; + temp = color1[2] - color2[2]; + the_error += temp * temp; + + return the_error; +} + +/* Calculate Error - compute the error between two colors + * + * Input parameters: + * Two 8 bit gray scale colors + * + * Returns: + * The squared error between the two colors + */ + +static int calc_error_8(unsigned char *color1, unsigned char *color2) +{ + int the_error; + + the_error = abs(color1[0] - color2[0]); + + return the_error; +} + +/* Find Size - Find the number of adjacent pixels of the same color + * + * Input Parameters: + * An 24 bit image, the current location inside the image, and the palette + * index of the color we are looking for + * + * Modified Parameters: + * A mask array used to prevent backtracking over already counted pixels + * + * Returns: + * Number of adjacent pixels found having the same color + */ + +static int find_size( /* in */ unsigned char *index, + /* in */ int x, + /* in */ int y, + /* in */ int width, + /* in */ int height, + /* in */ unsigned char *bitmap, + /* in/out */ unsigned char *mask) +{ + int count; + int x1, x2; + + if (y < 0 || y >= height || mask[y * width + x] == 1 || bitmap[3 * (y * width + x)] != index[0] || bitmap[3 * (y * width + x) + 1] != index[1] || bitmap[3 * (y * width + x) + 2] != index[2]) + return 0; + + for (x1 = x; x1 >= 0 && bitmap[3 * (y * width + x1)] == index[0] && bitmap[3 * (y * width + x1) + 1] == index[1] && bitmap[3 * (y * width + x1) + 2] == index[2] && mask[y * width + x] != 1; x1--) ; + x1++; + + for (x2 = x; x2 < width && bitmap[3 * (y * width + x2)] == index[0] && bitmap[3 * (y * width + x2) + 1] == index[1] && bitmap[3 * (y * width + x2) + 2] == index[2] && mask[y * width + x] != 1; x2++) ; + x2--; + + count = x2 - x1 + 1; + for (x = x1; x <= x2; x++) + mask[y * width + x] = 1; + + for (x = x1; x <= x2; x++) { + count += find_size(index, x, y - 1, width, height, bitmap, mask); + count += find_size(index, x, y + 1, width, height, bitmap, mask); + } + + return count; +} + +/* Find Size - Find the number of adjacent pixels of the same color + * + * Input Parameters: + * An 8 bit image, the current location inside the image, and the palette + * index of the color we are looking for + * + * Modified Parameters: + * A mask array used to prevent backtracking over already counted pixels + * + * Returns: + * Number of adjacent pixels found having the same color + */ + +static int find_size_8( /* in */ unsigned char *index, + /* in */ int x, + /* in */ int y, + /* in */ int width, + /* in */ int height, + /* in */ unsigned char *bitmap, + /* in/out */ unsigned char *mask) +{ + int count; + int x1, x2; + + if (y < 0 || y >= height || mask[y * width + x] == 1 || bitmap[(y * width + x)] != index[0]) + return 0; + + for (x1 = x; x1 >= 0 && bitmap[(y * width + x1)] == index[0] && mask[y * width + x] != 1; x1--) ; + x1++; + + for (x2 = x; x2 < width && bitmap[(y * width + x2)] == index[0] && mask[y * width + x] != 1; x2++) ; + x2--; + + count = x2 - x1 + 1; + for (x = x1; x <= x2; x++) + mask[y * width + x] = 1; + + for (x = x1; x <= x2; x++) { + count += find_size_8(index, x, y - 1, width, height, bitmap, mask); + count += find_size_8(index, x, y + 1, width, height, bitmap, mask); + } + + return count; +} + +/* Find Most Similar Neighbor - Given a position in an 24 bit bitmap and a color + * index, traverse over a blob of adjacent pixels having the same value. + * Return the color index of the neighbor pixel that has the most similar + * color. + * + * Input parameters: + * 24 bit bitmap, the current location inside the image, + * and the color index of the blob + * + * Modified parameters: + * Mask used to prevent backtracking + * + * Output parameters: + * Closest index != index and the error between the two colors squared + */ + +static void find_most_similar_neighbor( /* in */ unsigned char *index, + /* in/out */ unsigned char **closest_index, + /* in/out */ int *error_amt, + /* in */ int x, + /* in */ int y, + /* in */ int width, + /* in */ int height, + /* in */ unsigned char *bitmap, + /* in/out */ unsigned char *mask) +{ + int x1, x2; + int temp_error; + unsigned char *value, *temp; + + if (y < 0 || y >= height || mask[y * width + x] == 2) + return; + + temp = &bitmap[3 * (y * width + x)]; + + assert(closest_index != NULL); + + if (temp[0] != index[0] || temp[1] != index[1] || temp[2] != index[2]) { + value = temp; + + temp_error = calc_error(index, value); + + if (*closest_index == NULL || temp_error < *error_amt) + *closest_index = value, *error_amt = temp_error; + + return; + } + + for (x1 = x; x1 >= 0 && bitmap[3 * (y * width + x1)] == index[0] && bitmap[3 * (y * width + x1) + 1] == index[1] && bitmap[3 * (y * width + x1) + 2] == index[2]; x1--) ; + x1++; + + for (x2 = x; x2 < width && bitmap[3 * (y * width + x2)] == index[0] && bitmap[3 * (y * width + x2) + 1] == index[1] && bitmap[3 * (y * width + x2) + 2] == index[2]; x2++) ; + x2--; + + if (x1 > 0) { + value = &bitmap[3 * (y * width + x1 - 1)]; + + temp_error = calc_error(index, value); + + if (*closest_index == NULL || temp_error < *error_amt) + *closest_index = value, *error_amt = temp_error; + } + + if (x2 < width - 1) { + value = &bitmap[3 * (y * width + x2 + 1)]; + + temp_error = calc_error(index, value); + + if (*closest_index == NULL || temp_error < *error_amt) + *closest_index = value, *error_amt = temp_error; + } + + for (x = x1; x <= x2; x++) + mask[y * width + x] = 2; + + for (x = x1; x <= x2; x++) { + find_most_similar_neighbor(index, closest_index, error_amt, x, y - 1, width, height, bitmap, mask); + find_most_similar_neighbor(index, closest_index, error_amt, x, y + 1, width, height, bitmap, mask); + } +} + +/* Find Most Similar Neighbor - Given a position in an 8 bit bitmap and a color + * index, traverse over a blob of adjacent pixels having the same value. + * Return the color index of the neighbor pixel that has the most similar + * color. + * + * Input parameters: + * 8 bit bitmap, the current location inside the image, + * and the color index of the blob + * + * Modified parameters: + * Mask used to prevent backtracking + * + * Output parameters: + * Closest index != index and the error between the two colors squared + */ + +static void find_most_similar_neighbor_8( /* in */ unsigned char *index, + /* in/out */ unsigned char **closest_index, + /* in/out */ int *error_amt, + /* in */ int x, + /* in */ int y, + /* in */ int width, + /* in */ int height, + /* in */ unsigned char *bitmap, + /* in/out */ unsigned char *mask) +{ + int x1, x2; + int temp_error; + unsigned char *value, *temp; + + if (y < 0 || y >= height || mask[y * width + x] == 2) + return; + + temp = &bitmap[(y * width + x)]; + + assert(closest_index != NULL); + + if (temp[0] != index[0]) { + value = temp; + + temp_error = calc_error_8(index, value); + + if (*closest_index == NULL || temp_error < *error_amt) + *closest_index = value, *error_amt = temp_error; + + return; + } + + for (x1 = x; x1 >= 0 && bitmap[(y * width + x1)] == index[0]; x1--) ; + x1++; + + for (x2 = x; x2 < width && bitmap[(y * width + x2)] == index[0]; x2++) ; + x2--; + + if (x1 > 0) { + value = &bitmap[(y * width + x1 - 1)]; + + temp_error = calc_error_8(index, value); + + if (*closest_index == NULL || temp_error < *error_amt) + *closest_index = value, *error_amt = temp_error; + } + + if (x2 < width - 1) { + value = &bitmap[(y * width + x2 + 1)]; + + temp_error = calc_error_8(index, value); + + if (*closest_index == NULL || temp_error < *error_amt) + *closest_index = value, *error_amt = temp_error; + } + + for (x = x1; x <= x2; x++) + mask[y * width + x] = 2; + + for (x = x1; x <= x2; x++) { + find_most_similar_neighbor_8(index, closest_index, error_amt, x, y - 1, width, height, bitmap, mask); + find_most_similar_neighbor_8(index, closest_index, error_amt, x, y + 1, width, height, bitmap, mask); + } +} + +/* Fill - change the color of a blob + * + * Input parameters: + * The new color + * + * Modified parameters: + * 24 bit pixbuf and its mask (used to prevent backtracking) + */ + +static void fill( /* in */ unsigned char *to_index, + /* in */ int x, + /* in */ int y, + /* in */ int width, + /* in */ int height, + /* in/out */ unsigned char *bitmap, + /* in/out */ unsigned char *mask) +{ + int x1, x2; + + if (y < 0 || y >= height || mask[y * width + x] != 2) + return; + + for (x1 = x; x1 >= 0 && mask[y * width + x1] == 2; x1--) ; + x1++; + for (x2 = x; x2 < width && mask[y * width + x2] == 2; x2++) ; + x2--; + + assert(x1 >= 0 && x2 < width); + + for (x = x1; x <= x2; x++) { + bitmap[3 * (y * width + x)] = to_index[0]; + bitmap[3 * (y * width + x) + 1] = to_index[1]; + bitmap[3 * (y * width + x) + 2] = to_index[2]; + mask[y * width + x] = 3; + } + + for (x = x1; x <= x2; x++) { + fill(to_index, x, y - 1, width, height, bitmap, mask); + fill(to_index, x, y + 1, width, height, bitmap, mask); + } +} + +/* Fill - change the color of a blob + * + * Input parameters: + * The new color + * + * Modified parameters: + * 8 bit pixbuf and its mask (used to prevent backtracking) + */ + +static void fill_8( /* in */ unsigned char *to_index, + /* in */ int x, + /* in */ int y, + /* in */ int width, + /* in */ int height, + /* in/out */ unsigned char *bitmap, + /* in/out */ unsigned char *mask) +{ + int x1, x2; + + if (y < 0 || y >= height || mask[y * width + x] != 2) + return; + + for (x1 = x; x1 >= 0 && mask[y * width + x1] == 2; x1--) ; + x1++; + for (x2 = x; x2 < width && mask[y * width + x2] == 2; x2++) ; + x2--; + + assert(x1 >= 0 && x2 < width); + + for (x = x1; x <= x2; x++) { + bitmap[(y * width + x)] = to_index[0]; + mask[y * width + x] = 3; + } + + for (x = x1; x <= x2; x++) { + fill_8(to_index, x, y - 1, width, height, bitmap, mask); + fill_8(to_index, x, y + 1, width, height, bitmap, mask); + } +} + +/* Ignore - blob is big enough, mask it off + * + * Modified parameters: + * its mask (used to prevent backtracking) + */ + +static void ignore( /* in */ int x, + /* in */ int y, + /* in */ int width, + /* in */ int height, + /* in/out */ unsigned char *mask) +{ + int x1, x2; + + if (y < 0 || y >= height || mask[y * width + x] != 1) + return; + + for (x1 = x; x1 >= 0 && mask[y * width + x1] == 1; x1--) ; + x1++; + for (x2 = x; x2 < width && mask[y * width + x2] == 1; x2++) ; + x2--; + + assert(x1 >= 0 && x2 < width); + + for (x = x1; x <= x2; x++) + mask[y * width + x] = 3; + + for (x = x1; x <= x2; x++) { + ignore(x, y - 1, width, height, mask); + ignore(x, y + 1, width, height, mask); + } +} + +/* Recolor - conditionally change a feature's color to the closest color of all + * neighboring pixels + * + * Input parameters: + * The color palette, current blob size, and adaptive tightness + * + * Adaptive Tightness: (integer 1 to 256) + * 1 = really tight + * 256 = turn off the feature + * + * Modified parameters: + * 24 bit pixbuf and its mask (used to prevent backtracking) + * + * Returns: + * TRUE - feature was recolored, thus coalesced + * FALSE - feature wasn't recolored + */ + +static gboolean recolor( /* in */ double adaptive_tightness, + /* in */ int x, + /* in */ int y, + /* in */ int width, + /* in */ int height, + /* in/out */ unsigned char *bitmap, + /* in/out */ unsigned char *mask) +{ + unsigned char *index, *to_index; + int error_amt, max_error; + + index = &bitmap[3 * (y * width + x)]; + to_index = NULL; + error_amt = 0; + max_error = (int)(3.0 * adaptive_tightness * adaptive_tightness); + + find_most_similar_neighbor(index, &to_index, &error_amt, x, y, width, height, bitmap, mask); + + /* This condition only fails if the bitmap is all the same color */ + if (to_index != NULL) { + /* + * If the difference between the two colors is too great, + * don't coalesce the feature with its neighbor(s). This prevents a + * color from turning into its complement. + */ + + if (calc_error(index, to_index) > max_error) + fill(index, x, y, width, height, bitmap, mask); + else { + fill(to_index, x, y, width, height, bitmap, mask); + + return TRUE; + } + } + + return FALSE; +} + +/* Recolor - conditionally change a feature's color to the closest color of all + * neighboring pixels + * + * Input parameters: + * The color palette, current blob size, and adaptive tightness + * + * Adaptive Tightness: (integer 1 to 256) + * 1 = really tight + * 256 = turn off the feature + * + * Modified parameters: + * 8 bit pixbuf and its mask (used to prevent backtracking) + * + * Returns: + * TRUE - feature was recolored, thus coalesced + * FALSE - feature wasn't recolored + */ + +static gboolean recolor_8( /* in */ double adaptive_tightness, + /* in */ int x, + /* in */ int y, + /* in */ int width, + /* in */ int height, + /* in/out */ unsigned char *bitmap, + /* in/out */ unsigned char *mask) +{ + unsigned char *index, *to_index; + int error_amt; + + index = &bitmap[(y * width + x)]; + to_index = NULL; + error_amt = 0; + + find_most_similar_neighbor_8(index, &to_index, &error_amt, x, y, width, height, bitmap, mask); + + /* This condition only fails if the bitmap is all the same color */ + if (to_index != NULL) { + /* + * If the difference between the two colors is too great, + * don't coalesce the feature with its neighbor(s). This prevents a + * color from turning into its complement. + */ + + if (calc_error_8(index, to_index) > adaptive_tightness) + fill_8(index, x, y, width, height, bitmap, mask); + else { + fill_8(to_index, x, y, width, height, bitmap, mask); + + return TRUE; + } + } + + return FALSE; +} + +/* Despeckle Iteration - Despeckle all regions smaller than cur_size pixels + * + * Input Parameters: + * Current blob size, maximum blob size + * for all iterations (used to selectively recolor blobs), adaptive + * tightness and noise removal + * + * Modified Parameters: + * The 24 bit pixbuf is despeckled + */ + +static void despeckle_iteration( /* in */ int level, + /* in */ double adaptive_tightness, + /* in */ double noise_max, + /* in */ int width, + /* in */ int height, + /* in/out */ unsigned char *bitmap) +{ + unsigned char *mask; + int x, y; + int current_size; + int tightness; + + /* Size doubles each iteration level, so current_size = 2^level */ + current_size = 1 << level; + tightness = (int)(noise_max / (1.0 + adaptive_tightness * level)); + + mask = (unsigned char *)calloc(width * height, sizeof(unsigned char)); + for (y = 0; y < height; y++) { + for (x = 0; x < width; x++) { + if (mask[y * width + x] == 0) { + int size; + + size = find_size(&bitmap[3 * (y * width + x)], x, y, width, height, bitmap, mask); + + assert(size > 0); + + if (size < current_size) { + if (recolor(tightness, x, y, width, height, bitmap, mask)) + x--; + } else + ignore(x, y, width, height, mask); + } + } + } + + free(mask); +} + +/* Despeckle Iteration - Despeckle all regions smaller than cur_size pixels + * + * Input Parameters: + * Current blob size, maximum blob size + * for all iterations (used to selectively recolor blobs), adaptive + * tightness and noise removal + * + * Modified Parameters: + * The 8 bit pixbuf is despeckled + */ + +static void despeckle_iteration_8( /* in */ int level, + /* in */ double adaptive_tightness, + /* in */ double noise_max, + /* in */ int width, + /* in */ int height, + /* in/out */ unsigned char *bitmap) +{ + unsigned char *mask; + int x, y; + int current_size; + int tightness; + + /* Size doubles each iteration level, so current_size = 2^level */ + current_size = 1 << level; + tightness = (int)(noise_max / (1.0 + adaptive_tightness * level)); + + mask = (unsigned char *)calloc(width * height, sizeof(unsigned char)); + for (y = 0; y < height; y++) { + for (x = 0; x < width; x++) { + if (mask[y * width + x] == 0) { + int size; + + size = find_size_8(&bitmap[(y * width + x)], x, y, width, height, bitmap, mask); + + assert(size > 0); + + if (size < current_size) { + if (recolor_8(tightness, x, y, width, height, bitmap, mask)) + x--; + } else + ignore(x, y, width, height, mask); + } + } + } + + free(mask); +} + +/* Despeckle - Despeckle a 8 or 24 bit image + * + * Input Parameters: + * Adaptive feature coalescing value, the despeckling level and noise removal + * + * Despeckling level (level): Integer from 0 to ~20 + * 0 = perform no despeckling + * An increase of the despeckling level by one doubles the size of features. + * The Maximum value must be smaller then the logarithm base two of the number + * of pixels. + * + * Feature coalescing (tightness): Real from 0.0 to ~8.0 + * 0 = Turn it off (whites may turn black and vice versa, etc) + * 3 = Good middle value + * 8 = Really tight + * + * Noise removal (noise_removal): Real from 1.0 to 0.0 + * 1 = Maximum noise removal + * You should always use the highest value, only if certain parts of the image + * disappear you should lower it. + * + * Modified Parameters: + * The bitmap is despeckled. + */ + +void despeckle( /* in/out */ at_bitmap * bitmap, + /* in */ int level, + /* in */ gfloat tightness, + /* in */ gfloat noise_removal, + /* exception handling */ at_exception_type * excep) +{ + int i, planes, max_level; + short width, height; + unsigned char *bits; + double noise_max, adaptive_tightness; + + planes = AT_BITMAP_PLANES(bitmap); + noise_max = noise_removal * 255.0; + width = AT_BITMAP_WIDTH(bitmap); + height = AT_BITMAP_HEIGHT(bitmap); + bits = AT_BITMAP_BITS(bitmap); + max_level = (int)(log(width * height) / log(2.0) - 0.5); + if (level > max_level) + level = max_level; + adaptive_tightness = (noise_removal * (1.0 + tightness * level) - 1.0) / level; + + if (planes == 3) { + for (i = 0; i < level; i++) + despeckle_iteration(i, adaptive_tightness, noise_max, width, height, bits); + } else if (planes == 1) { + for (i = 0; i < level; i++) + despeckle_iteration_8(i, adaptive_tightness, noise_max, width, height, bits); + } else { + LOG("despeckle: %u-plane images are not supported", planes); + at_exception_fatal(excep, "despeckle: wrong plane images are passed"); + return; + } + +} |