rgb

How to convert RGB to HSL in C?

由 匆匆过客 提交于 2020-01-23 11:47:51
问题 How do I convert RGB to HSL in C/C++? (Note: This is a (short) self-answer -- I posted it here so people can find it quickly with a search.) 回答1: Translating the code from here, you get: // Assuming sizeof(unsigned int) == 4 * sizeof(unsigned char) unsigned int RgbToHsl(unsigned int rgb) // Alpha value is simply passed through { #ifdef __cplusplus using std::max; using std::min; #endif double r = (rgb >> (0 * CHAR_BIT)) & UCHAR_MAX, g = (rgb >> (1 * CHAR_BIT)) & UCHAR_MAX, b = (rgb >> (2 *

Calculating heat map colours

由 丶灬走出姿态 提交于 2020-01-22 20:55:46
问题 I'm working on a heat map made up of an HTML table. This table contains n cells and has a lowest value and a highest value (highest is always higher than lowest). Each cell has a cell value. All these values are ints. Cells with the lowest value are meant to be a light blue, scaling across to the point where the cells with the highest value are a deep red. See gradient below for an ideal range: To calculate the hex colour value of each individual cell, I look at the lowest and highest values

【darknet源码解析-29】图像RGB2HSV与HSV2RGB格式互转

由 喜欢而已 提交于 2020-01-22 18:24:23
本系列为darknet源码解析，由于在image.c中涉及到图像的RGB,YUV,HSV格式,在本文我们将image.c中涉及到的rgb_to_hsv()函数以及hsv_to_rgb()函数进行解析. RGB格式转为HSV格式 如果max=0 如果max!=0 对应源码如下: void rgb_to_hsv(image im) { assert(im.c == 3); int i, j; float r, g, b; float h, s, v; for(j = 0; j < im.h; ++j){ for(i = 0; i < im.w; ++i){ r = get_pixel(im, i , j, 0);//获取指定位置指定通道的像素值 g = get_pixel(im, i , j, 1); b = get_pixel(im, i , j, 2); float max = three_way_max(r,g,b);//获取rgb最大值 float min = three_way_min(r,g,b); float delta = max - min; v = max; if(max == 0){ s = 0; h = 0; }else{ s = delta/max; if(r == max){ h = (g - b) / delta; } else if (g == max)

How to convert gray scale png image to RGB from comand line using image magick

由 浪子不回头ぞ 提交于 2020-01-22 16:05:17
问题 I am trying to convert an png Gray scale image to RGB png image using the following command. convert HopeLoveJoy.png -size 1x1 -fill "rgba(0%,1%,2%,0)" -draw "color 511,511 point" out_test.png By using the above the above command I am able to convert but the color of the image is getting changed. Is any thing wrong in the command?? Any help is appreciated. Thanks in advance. 回答1: If, as your question title implies, you really just want to go from greyscale to sRGB colorspace, use this:

How to convert gray scale png image to RGB from comand line using image magick

由 被刻印的时光 ゝ 提交于 2020-01-22 16:03:27
问题 I am trying to convert an png Gray scale image to RGB png image using the following command. convert HopeLoveJoy.png -size 1x1 -fill "rgba(0%,1%,2%,0)" -draw "color 511,511 point" out_test.png By using the above the above command I am able to convert but the color of the image is getting changed. Is any thing wrong in the command?? Any help is appreciated. Thanks in advance. 回答1: If, as your question title implies, you really just want to go from greyscale to sRGB colorspace, use this:

How to convert gray scale png image to RGB from comand line using image magick

由 时光毁灭记忆、已成空白 提交于 2020-01-22 16:03:07
问题 I am trying to convert an png Gray scale image to RGB png image using the following command. convert HopeLoveJoy.png -size 1x1 -fill "rgba(0%,1%,2%,0)" -draw "color 511,511 point" out_test.png By using the above the above command I am able to convert but the color of the image is getting changed. Is any thing wrong in the command?? Any help is appreciated. Thanks in advance. 回答1: If, as your question title implies, you really just want to go from greyscale to sRGB colorspace, use this:

ImageMagick Reduces Colorspace to Gray

由 纵然是瞬间 提交于 2020-01-21 03:11:32
问题 I convert RGB and CMYK TIFF images to RGB JPEGs using convert a.tif -colorspace rgb a.jpg If the TIFF image contains only gray pixels, the colorspace of the resulting JPEG is gray, not RGB. How can I force ImageMagick to always use RGB? 回答1: Try this: convert a.tif -colorspace rgb -type truecolor a.jpg However, I have to ask: How exactly do you determine your verdict 'colorspace of resulting JPEG is gray, not RGB' ?!? The ImageMagick tool identify can look at the colorspace used by files. If

Python 3 print text using 24bit (HTML5) rgb code

由 不问归期 提交于 2020-01-16 00:43:07
问题 In my script I wish to input rgb(red,green,blue) color code 24bit (HTML5) as background color and as text color. But I can't get it to work. The resulting color code is different from what I copied from the w3schools Color Picker. See my Repl.it code example or code bellow: from sty import fg, bg, ef, rs, Rule import time import sys def isInteger(n): #function from the internet that checks if a float is a int if n%2 == 0 or (n+1)%2 == 0: return True return False def make_int(value): try: int

Replace all rgb values above a threshold

由 瘦欲@ 提交于 2020-01-15 05:26:06
问题 I have a numpy 3 d array full of RGB values like for exemple shape = (height,width,3) matrix = np.array( [[[0,0.5,0.6],[0.9,1.2,0]]) I have to replace the RGB value if any of the values is above a threshold, for exemple threshold = 0.8, replacement = [2,2,2] then matrix = [[[0,0.5,0.6],[2,2,2]] How can I do this on a efficient mannner with numpy ? Currently I am using a double for loop and checking if any rgb value is above treshold, i replace it however this is quiet slow for n = 4000 array.

Changing color's tone using python

由 自闭症网瘾萝莉.ら 提交于 2020-01-15 03:15:06
问题 I'm looking for a way to change a color's tone, knowing it's RGB composition, then replace all instances of the old RGB with the obtained RGB. For example, I'd like red to become purple, light red, light purple, etc... It can be done in photoshop by changing a color's hue. What I've thought so far is the following: convert RGB to HLS, then change the Hue. Here's the code so far (multiple colors are changed, not just one, defined in the "list" list): (As you might notice, I'm just a beginner
订阅 rgb