| """ | |
| ============== | |
| Frame grabbing | |
| ============== | |
| Use a MovieWriter directly to grab individual frames and write them to a | |
| file. This avoids any event loop integration, and thus works even with the Agg | |
| backend. This is not recommended for use in an interactive setting. | |
| Output generated via `matplotlib.animation.Animation.to_jshtml`. | |
| """ | |
| import numpy as np | |
| import matplotlib | |
| matplotlib.use("Agg") | |
| import matplotlib.pyplot as plt | |
| from matplotlib.animation import FFMpegWriter | |
| # Fixing random state for reproducibility | |
| np.random.seed(19680801) | |
| metadata = dict(title='Movie Test', artist='Matplotlib', | |
| comment='Movie support!') | |
| writer = FFMpegWriter(fps=15, metadata=metadata) | |
| fig = plt.figure() | |
| l, = plt.plot([], [], 'k-o') | |
| plt.xlim(-5, 5) | |
| plt.ylim(-5, 5) | |
| x0, y0 = 0, 0 | |
| with writer.saving(fig, "writer_test.mp4", 100): | |
| for i in range(100): | |
| x0 += 0.1 * np.random.randn() | |
| y0 += 0.1 * np.random.randn() | |
| l.set_data(x0, y0) | |
| writer.grab_frame() | |