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• Livestream programatically generated audio/video over RTMP [on hold]

  13 février 2018, par user2649681

  I’m looking for a way to stream data generated by a program over RTMP without saving it to an intermediate file to then stream with ffmpeg. For example, if I have a program to run that constantly generates white noise as samples of audio(e.g. a function that outputs a random sample run within an infinite loop), and, if possible, a screen of a solid, random color, is there a way for me to this audio over RTMP more or less as it’s being generated ? I would imagine, if this is possible, it may involve something along the lines of building up buffers of a fixed number of audio samples and then streaming it somehow over RTMP.

• FFMPEG not processing whole video for frames extraction [closed]

  17 juillet 2023, par Nuttertools

  I'm experiencing a weird issue with FFMPEG, on Windows.

  


  I'm trying to extract every single frames from a video, I use ffmpeg to do that with the following command :

  


  ffmpeg -i "input.mp4" "%04d.png"

  


  The extracted frames amount is random, I tested with several videos, let's take an example with a video that counts 2500 frames, sometimes ffmpeg will extract 500 frames, sometimes 1200, sometimes more, sometimes less, it doesn't make any sense.

  


  I have nothing in logs (tried verbose, nothing in console, nothing in dump file after -report cmd added too)

  


  It just stops before the ends of the video, at random frames ...

  


  Sometimes the whole video gets processed aswell, but that is RARE !

  


  Do you have any idea what could be the issue ?

  


  Thanks.

  


• Difficulties saving an animation (matplotlib)

  14 avril 2020, par Ben C.

  I have a simple animation that I want to save. I followed the example : https://matplotlib.org/examples/animation/basic_example_writer.html

  



  But I get the following error : RuntimeError : Requested MovieWriter (ffmpeg) not available

  



  I installed ffmpeg and checked via ffmpeg -version that it really is installed and the path correct.

  



  Here is my code :

  



  import numpy as np
import matplotlib.animation as animation
import matplotlib.pyplot as plt

# Set up formatting for the movie files
Writer = animation.writers['ffmpeg']
writer = Writer(fps=15, metadata=dict(artist='Me'), bitrate=1800)

fig, ax = plt.subplots()

x = np.random.uniform(0,1)
y = np.random.uniform(0,1)


scat = ax.scatter(x,y, color= 'blue')
circle = plt.Circle((x,y), radius=0.1, color='blue', fill=False, lw=0.5)
ax.add_patch(circle)

def init():
    scat = ax.scatter(x, y, color = 'blue')
    circle = plt.Circle((x,y), radius=0.1, color='blue', fill=False, lw=0.5)

def animate(i):
    random = np.random.uniform(0,1)
    if random < 0.5:
        scat.set_color('red')
        circle.set_edgecolor('blue')
    else:
        scat.set_color('blue')
        circle.set_edgecolor('red')
    return circle, scat,


ani = animation.FuncAnimation(fig, animate, init_func=init(), interval=1000, blit=True)
ani.save('test.mp4', writer=writer)


  



  None of the proposed solution in RuntimeError : No MovieWriters available in Matplotlib animation worked for me. Any ideas ?

  



  Edit : I am using Windows (10)