浙江省工程造价信息网,网站排名云优化工具,百度应用中心,优秀网站建设模板因为需要将结果动画保存为MP4视频文件需要ffmepg软件的的支持。
一#xff1a;安装ffmpeg软件#xff1a;
ffmpeg是一套可以用来记录、转换数字音频、视频#xff0c;并能将其转化为流的开源计算机程序。采用LGPL或GPL许可证。它提供了录制、转换以及流化音视频的完整解决方…因为需要将结果动画保存为MP4视频文件需要ffmepg软件的的支持。
一安装ffmpeg软件
ffmpeg是一套可以用来记录、转换数字音频、视频并能将其转化为流的开源计算机程序。采用LGPL或GPL许可证。它提供了录制、转换以及流化音视频的完整解决方案。下载网址为https://ffmpeg.zeranoe.com/builds/。本实验下载的是windows 64位Static的版本下载的压缩包为ffmpeg-20190407-ecdaa4b-win64-static.zip解压然后将bin目录加入系统环境变量的路径中例如解压后bin目录为C:\ProgramFiles\ffmpeg-20190407-ecdaa4b-win64-static\bin。 最后测试ffmpeg是否配置成功打开Windows的cmd窗口输入ffmpeg -version。如果能看到如下ffmpeg关于软件版本的信息表示成功了。
ffmpeg version N-93542-gecdaa4b4fa Copyright (c) 2000-2019 the FFmpeg developersbuilt with gcc 8.2.1 (GCC) 20190212
configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig
--enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libblu
ray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable
-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --ena
ble-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-l
ibvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --e
nable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable
-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enab
le-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enab
le-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --ena
ble-dxva2 --enable-avisynth --enable-libopenmpt
libavutil 56. 26.100 / 56. 26.100
libavcodec 58. 48.101 / 58. 48.101
libavformat 58. 27.100 / 58. 27.100
libavdevice 58. 7.100 / 58. 7.100
libavfilter 7. 48.100 / 7. 48.100
libswscale 5. 4.100 / 5. 4.100
libswresample 3. 4.100 / 3. 4.100
libpostproc 55. 4.100 / 55. 4.100二、运行保存Python示例程序
示例程序一正弦波动画 A simple example of an animated plotimport numpy as np
from matplotlib import pyplot as plt
from matplotlib import animation# First set up the figure, the axis, and the plot element we want to animate
fig plt.figure()
# create our line object which will be modified in the animation
ax plt.axes(xlim(0, 2), ylim(-2, 2))
# we simply plot an empty line: well add data to the line later
line, ax.plot([], [], lw2)# initialization function: plot the background of each frame
def init():line.set_data([], [])return line,# animation function. This is called sequentially
# It takes a single parameter, the frame number i
def animate(i):x np.linspace(0, 2, 1000)y np.sin(2 * np.pi * (x - 0.01 * i)) # update the dataline.set_data(x, y)return line,# Makes an animation by repeatedly calling a function func
# frames can be a generator, an iterable, or a number of frames.
# interval draws a new frame every interval milliseconds.
# blitTrue means only re-draw the parts that have changed.
# 在这里设置一个200帧的动画每帧之间间隔20毫秒
anim animation.FuncAnimation(fig, animate, init_funcinit,frames200, interval20, blitTrue)
# save the animation as an mp4. This requires ffmpeg or mencoder to be
# installed. The extra_args ensure that the x264 codec is used, so that
# the video can be embedded in html5. You may need to adjust this for
# your system: for more information, see
# http://matplotlib.sourceforge.net/api/animation_api.html
#保存的动画视频文件名为当前文件夹下的basic_animation.mp4帧率为30帧每秒格式为MP4。
anim.save(basic_animation.mp4, fps30, extra_args[-vcodec, libx264])plt.show() # plt.show() 会一直循环播放动画
示例程序2贝叶斯曲线动画
import mathimport numpy as np
import matplotlib.pyplot as plt
from matplotlib.animation import FuncAnimationdef beta_pdf(x, a, b):return (x ** (a - 1) * (1 - x) ** (b - 1) * math.gamma(a b)/ (math.gamma(a) * math.gamma(b)))class UpdateDist(object):def __init__(self, ax, prob0.5):self.success 0self.prob probself.line, ax.plot([], [], k-)self.x np.linspace(0, 1, 200)self.ax ax# Set up plot parametersself.ax.set_xlim(0, 1)self.ax.set_ylim(0, 15)self.ax.grid(True)# This vertical line represents the theoretical value, to# which the plotted distribution should converge.self.ax.axvline(prob, linestyle--, colorblack)def init(self):self.success 0self.line.set_data([], [])return self.line,def __call__(self, i):# This way the plot can continuously run and we just keep# watching new realizations of the processif i 0:return self.init()# Choose success based on exceed a threshold with a uniform pickif np.random.rand(1, ) self.prob:self.success 1y beta_pdf(self.x, self.success 1, (i - self.success) 1)self.line.set_data(self.x, y)return self.line,# Fixing random state for reproducibility
np.random.seed(19680801)fig, ax plt.subplots()
ud UpdateDist(ax, prob0.7)
anim FuncAnimation(fig, ud, framesnp.arange(100), init_funcud.init,interval5, blitTrue)
#保存动画视频文件名为当前文件夹下的bayes_animation.mp4帧率为30帧每秒格式为MP4。
anim.save(bayes_animation.mp4, fps30, extra_args[-vcodec, libx264])
plt.show()三运行程序并查看结果。
请注意以上程序直接在Python的IDE环境中运行例如PyCharm和Jupyter Notebook运行可能报错或者只显示一张静态的空白图。
正确的方式是在Windows的cmd命令窗口下执行命令python 代码文件名.py。才能看到动态的结果并且得到相应的MP4文件。
