R可视化——图片颜色提取及应用（以jpg格式图片为例）

设置工作目录、加载R包

rm(list = ls())
#设置工作目录
setwd("D:\\图片颜色提取")
#加载R包
library(RImagePalette)
library(imager)
library(scales)
library(ggplot2)
library(ggprism)
library(reshape)
library(ggalluvial)

加载图片并提取颜色

1、图片加载及预览——jpg格式图片加载主要基于imager包中的load.image()函数：

##图1
imgjpg1 <- load.image("test1.jpg")#读取图片
plot(imgjpg1,xlim = c(1,width(imgjpg1)),ylim = c(height(imgjpg1),1)) #显示图片

image.png

2、提取图片颜色——主要基于RImagePalette包中的image_palette()函数：

#提取图片颜色
df_color1 <- image_palette(imgjpg1,n=10)
show_col(df_color1)#展示

image.png

3、同样的原理提取其他图片颜色：

##图2
imgjpg2 <- load.image("test2.jpg")#读取图片
plot(imgjpg2,xlim = c(1,width(imgjpg2)),ylim = c(height(imgjpg2),1)) #显示图片
#提取图片颜色
df_color2 <- image_palette(imgjpg2,n=10)
show_col(df_color2)

image.png image.png

##图3
imgjpg3 <- load.image("test3.jpg")#读取图片
plot(imgjpg3,xlim = c(1,width(imgjpg3)),ylim = c(height(imgjpg3),1)) #显示图片
#提取图片颜色
df_color3 <- image_palette(imgjpg3,n=10)
show_col(df_color3)

image.png
image.png

##图4
imgjpg4 <- load.image("test4.jpg")#读取图片
plot(imgjpg4,xlim = c(1,width(imgjpg4)),ylim = c(height(imgjpg4),1)) #显示图片
#提取图片颜色
df_color4 <- image_palette(imgjpg4,n=10)
show_col(df_color4)

image.png
image.png

应用提取图片的颜色绘图

1、构造绘图数据

df<-data.frame(samples=c('a','b','c','d','e','f','g','h','i','j'),
               A=c(0.12,0.15,0.1,0.07,0.1,0.1,0.08,0.1,0.13,0.05),
               B=c(0.35,0.1,0.05,0.05,0.05,0.1,0.1,0.05,0.1,0.05),
               C=c(0.25,0.15,0.1,0.07,0.1,0.1,0.05,0.05,0.08,0.05),
               D=c(0.05,0.2,0.1,0.2,0.1,0.1,0.1,0.05,0.05,0.05))
#变量格式转换,宽数据转化为长数据,方便后续作图
df1 <- melt(df,id.vars = 'samples',measure.vars = c('A','B','C','D'))
names(df1)[1:2] <- c("group","X")  #修改列名

image.png

2、绘图

#绘图
p<-ggplot(df1, aes( x = X,y=100 * value,fill = group,
                 stratum = group, alluvium = group))+
  geom_stratum(width = 0.7, color='white')+
  geom_alluvium(alpha = 0.5,
                width = 0.7,
                color='white',
                size = 1,
                curve_type = "linear")+
  scale_y_continuous(expand = c(0,0))+
  labs(x="Samples",y="Relative Abundance(%)",
       fill="group")+
  theme_prism(palette = "candy_bright",
              base_fontface = "plain", 
              base_family = "serif", 
              base_size = 16, 
              base_line_size = 0.8, 
              axis_text_angle = 45)+ 
  theme(legend.position = 'top')
p

image.png

3、应用绘图颜色并拼图

#应用颜色
p2<-p+scale_fill_manual(values = df_color1)
p3<-p+scale_fill_manual(values = df_color2)
p4<-p+scale_fill_manual(values = df_color3)
p5<-p+scale_fill_manual(values = df_color4)
#拼图
cowplot::plot_grid(p2,p3,p4,p5,ncol = 2)

image.png

图片来源于网络（https://zhuanlan.zhihu.com/p/155963612），仅用于学习交流！