機器學習
R語言
R語言與黑白照片
R語言與閾值
OCR文字識別
R語言與OCR文字識別
R語言圖像處理
R語言黑白照片
去色
包預設了多個參數(shù)勿璃，其中一個
# Sun Sep 27 00:27:20 2020 -
# 字符編碼：UTF-8
# R 版本：R x64 4.0.2 for window 10
# cgh163email@163.com
# 個人筆記不負責任
# —— 拎了個梨??
.rs.restartR()
rm(list=ls());gc()
library(magick)
require(image.binarization)
# image.binarization對圖像進行二值化以增強光學字符識別
#它是依賴于magick的
#
f <- system.file("extdata", "doxa-example.png", package = "image.binarization")
img <- image_read(f)
# Sun Sep 27 00:34:47 2020 -# 去色：-----------------------------
img2 <- image_convert(img, format = "PGM", colorspace = "Gray")
par(mfrow=c(1,2))
plot(img)
plot(img2,main='image_convert去色')
# 灰度直方圖的閾值選擇方法:
# 請注意揭璃，重要的是，您必須以整數(shù)形式提供窗口/閾值/對比度限制悔雹，minN复哆，字形參數(shù)（例如欣喧，在75L中），而其他參數(shù)則以數(shù)字形式提供梯找。
#
binary <- image_binarization(img, type = "otsu")
binary
# 貝恩森：窗口（75L）续誉，k（0.2），閾值（100L）初肉，對比度極限（25L）:
binary <- image_binarization(img,
type = "bernsen",
opts = list(
window = 50L,
k = 0.2,
threshold = 50L
))
binary
# 尼布萊克: window(75L), k(0.2):
binary <- image_binarization(img, type = "niblack", opts = list(window = 75L, k = 0.2))
binary
# 衛(wèi)星式樣：窗（75L）酷鸦，k（0.2）:
binary <- image_binarization(img, type = "sauvola")
binary
# 狼
binary <- image_binarization(img, type = "wolf")
binary
# nick: window(75L), k(-0.2):
binary <- image_binarization(img, type = "nick", opts = list(window = 75L, k = -0.2))
binary
# gatos: window(75L), k(0.2), glyph(60L):
binary <- image_binarization(img, type = "gatos", opts = list(window = 75L, k = 0.2, glyph = 50L))
binary
# su: window(75L), minN(75L)
binary <- image_binarization(img, type = "su", opts = list(window = 20L))
binary
# trsingh: window(75L), k(0.2)
binary <- image_binarization(img, type = "trsingh")
binary
# bataineh：無:
binary <- image_binarization(img, type = "bataineh")
binary
# wan: window(75L), k(0.2):
binary <- image_binarization(img, type = "wan")
binary
# isauvola: window(75L), k(0.2):
binary <- image_binarization(img, type = "isauvola", opts = list(window = 75L, k = 0.2))
binary
