python3.6环境下安装freetype库和基本使用方法(推荐)

Irisa ·

更新时间:2024-11-15

· 601 次阅读

FreeType库是一个完全免费（开源）的、高质量的且可移植的字体引擎，它提供统一的接口来访问多种字体格式文件，包括TrueType, OpenType, Type1, CID, CFF, Windows FON/FNT, X11 PCF等。在做图像展示的时候，可以写入中文文字，效果还是很好。

在这里插入图片描述

在之前安装库时基本都是直接切换到python3.6环境下直接pip install XXX，在安装freetype直接pip install freetype不可以了，查了半天又是编译又是官网下载的，太麻烦，不推荐。

（1）正确的安装方法：
注意：一定要加上 -py


pip install freetype-py

（2）常用调用方法

已经封装好了一个文件，可直接保存后调用。


import freetype
import copy
class put_chinese_text(object):
 def __init__(self, ttf):
  self._face = freetype.Face(ttf)
 def draw_text(self, image, pos, text, text_size, text_color):
  '''
  draw chinese(or not) text with ttf
  :param image:  image(numpy.ndarray) to draw text
  :param pos:  where to draw text
  :param text:  the context, for chinese should be unicode type
  :param text_size: text size
  :param text_color:text color
  :return:   image
  '''
  self._face.set_char_size(text_size * 64)
  metrics = self._face.size
  ascender = metrics.ascender / 64.0
  # descender = metrics.descender/64.0
  # height = metrics.height/64.0
  # linegap = height - ascender + descender
  ypos = int(ascender)
  text = text
  img = self.draw_string(image, pos[0], pos[1] + ypos, text, text_color)
  return img
 def draw_string(self, img, x_pos, y_pos, text, color):
  '''
  draw string
  :param x_pos: text x-postion on img
  :param y_pos: text y-postion on img
  :param text: text (unicode)
  :param color: text color
  :return:  image
  '''
  prev_char = 0
  pen = freetype.Vector()
  pen.x = x_pos << 6 # div 64
  pen.y = y_pos << 6
  hscale = 1.0
  matrix = freetype.Matrix(int(hscale) * 0x10000, int(0.2 * 0x10000), \
         int(0.0 * 0x10000), int(1.1 * 0x10000))
  cur_pen = freetype.Vector()
  pen_translate = freetype.Vector()
  image = copy.deepcopy(img)
  for cur_char in text:
   self._face.set_transform(matrix, pen_translate)
   self._face.load_char(cur_char)
   kerning = self._face.get_kerning(prev_char, cur_char)
   pen.x += kerning.x
   slot = self._face.glyph
   bitmap = slot.bitmap
   cur_pen.x = pen.x
   cur_pen.y = pen.y - slot.bitmap_top * 64
   self.draw_ft_bitmap(image, bitmap, cur_pen, color)
   pen.x += slot.advance.x
   prev_char = cur_char
  return image
 def draw_ft_bitmap(self, img, bitmap, pen, color):
  '''
  draw each char
  :param bitmap: bitmap
  :param pen: pen
  :param color: pen color e.g.(0,0,255) - red
  :return:  image
  '''
  x_pos = pen.x >> 6
  y_pos = pen.y >> 6
  cols = bitmap.width
  rows = bitmap.rows
  glyph_pixels = bitmap.buffer
  for row in range(rows):
   for col in range(cols):
    if glyph_pixels[row * cols + col] != 0:
     try:
      img[y_pos + row][x_pos + col][0] = color[0]
      img[y_pos + row][x_pos + col][1] = color[1]
      img[y_pos + row][x_pos + col][2] = color[2]
     except:
      continue
if __name__ == '__main__':
 # just for test
 import cv2
 line = '毛不易'
 img = cv2.imread('./aa.jpg')
 color_ = (0, 255, 0) # Green
 pos = (3, 3)
 text_size = 24
 ft = put_chinese_text('yahei.ttf')
 image = ft.draw_text(img, pos, line, text_size, color_)
 cv2.imshow('ss', image)
 cv2.waitKey(0)

总结

到此这篇关于python3.6环境下安装freetype库和基本使用方法(推荐)的文章就介绍到这了,更多相关python3.6安装freetype库内容请搜索软件开发网以前的文章或继续浏览下面的相关文章希望大家以后多多支持软件开发网！

您可能感兴趣的文章:python2和python3应该学哪个(python3.6与python3.7的选择)Pycharm+django2.2+python3.6+MySQL实现简单的考试报名系统python3.6 如何将list存入txt后再读出list的方法python3.6环境安装+pip环境配置教程图文详解

freetype 环境方法 Python3 Python

1024 个赞