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Diffstat (limited to 'alg_interpolate_rgb_scalar.h')
-rw-r--r-- | alg_interpolate_rgb_scalar.h | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/alg_interpolate_rgb_scalar.h b/alg_interpolate_rgb_scalar.h new file mode 100644 index 0000000..aa17c54 --- /dev/null +++ b/alg_interpolate_rgb_scalar.h @@ -0,0 +1,100 @@ +/** +* @file alg_interpolate_rgb_scalar.h +* @brief RGB pixel interpolation (scalar code) +* @author Patrick Roth - roth@stettbacher.ch +* @version 1.0 +* @date 2015-11-09 +* @copyright 2012-2016 Stettbacher Signal Processing AG +* +* @remarks +* +* <PRE> +* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA +* </PRE> +* +*/ + + +/* + * This code inplements an RGB pixel interpolator and is independent of the pixel-bit-depth. Including this code at the + * C-Source file will define the pixel-bit-depth (see camera_calib.c). + */ +// static void interpolate_rgb8_scalar(uint8_t *img_out, const int x, const int y, const int height, const int width, +// const uint8_t *img_in, const int coord_x, const int coord_y, const int scale_fact) +// static void interpolate_rgb16_scalar(uint16_t *img_out, const int x, const int y, const int height, const int width, +// const uint16_t *img_in, const int coord_x, const int coord_y, const int scale_fact) +{ + int x_start, y_start, x_end, y_end, index_start, index_end; + int wheight_x, wheight_y, a11, a12, a21, a22; + int red, green, blue; + int index; + const int max_val = (1<<scale_fact); + + + // calculate pixel index of destination image (calibrated image) + index = ((y*width)+x)*3; + + if((coord_x>>scale_fact) > width || (coord_y>>scale_fact) > height || coord_x < 0 || coord_y < 0) { + // out of range --> return black value + img_out[index] = 0; + img_out[index+1] = 0; + img_out[index+2] = 0; + return; + } + + red = 0; + green = 0; + blue = 0; + + x_start = coord_x>>scale_fact; + y_start = coord_y>>scale_fact; + x_end = x_start + 1; + y_end = y_start + 1; + index_start = (y_start*width + x_start)*3; + index_end = (y_end*width + x_end)*3; + + // calculate wheights + wheight_x = coord_x % max_val; + wheight_y = coord_y % max_val; + a11 = (max_val - wheight_x)*(max_val - wheight_y); + a12 = wheight_x*(max_val - wheight_y); + a21 = (max_val - wheight_x)*wheight_y; + a22 = wheight_x*wheight_y; + + /* + * handle border region separately + */ + if(x_end < width || y_end < height) { + // pixels are not lying on border region + red = img_in[index_start]*a11 + + img_in[index_start+3]*a12 + + img_in[index_end-3]*a21 + + img_in[index_end]*a22; + + green = img_in[index_start+1]*a11 + + img_in[index_start+1+3]*a12 + + img_in[index_end+1-3]*a21 + + img_in[index_end+1]*a22; + + blue = img_in[index_start+2]*a11 + + img_in[index_start+2+3]*a12 + + img_in[index_end+2-3]*a21 + + img_in[index_end+2]*a22; + } + + img_out[index] = red >> (2*scale_fact); + img_out[index+1] = green >> (2*scale_fact); + img_out[index+2] = blue >> (2*scale_fact); +} |