旧开发板之废物利用
Posted on Sat 13 July 2024 in Journal
| Abstract | 深度学习笔记 |
|---|---|
| Authors | Walter Fan |
| Category | learning note |
| Status | v1.0 |
| Updated | 2024-07-13 |
| License | CC-BY-NC-ND 4.0 |
仓库里有若干个旧的 Jetson Nano 开发板, 内存和硬盘都不够用, 放在柜子里吃灰. 最近把它们又从仓库里翻了出来, 用它们做自动播放视频, 用来模拟超声机的接入, 还是挺好用的.
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准备好一些事先录制好的超声视频
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写一个脚本, 读取视频文件, 然后按照指定次数播放
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playback.sh
cd /home/walter/test/script
video_path="/home/walter/test/video"
video_file="20240529.mp4"
loop_count=864000000
if [ $# -gt 0 ]; then
video_file=$1
echo "video file : $video_path/$video_file"
fi
if [ $# -gt 1 ]; then
loop_count=$2
echo "loop_count : $loop_count"
fi
echo "playback $video_path/$video_file $loop_count"
DISPLAY=:0 python3 media_player.py $video_path/$video_file $loop_count
- media_play.py
import gi
gi.require_version('Gst', '1.0')
from gi.repository import Gst, GLib
Gst.init(None)
num_loops = 0
def play_media(file_path):
pipeline_str = "playbin uri=file://" + file_path
pipeline = Gst.parse_launch(pipeline_str)
message_bus = pipeline.get_bus()
loop = GLib.MainLoop()
def on_message(bus, message):
global num_loops
t = message.type
if t == Gst.MessageType.EOS:
if num_loops > 0:
print(f"left run count: {num_loops}")
pipeline.set_state(Gst.State.READY)
pipeline.set_state(Gst.State.PLAYING)
num_loops -= 1
else:
print(f"quit because left run count is {num_loops}")
loop.quit()
elif t == Gst.MessageType.ERROR:
err, debug = message.parse_error()
print("Error: %s" % err)
loop.quit()
message_bus.add_signal_watch()
message_bus.connect("message", on_message)
pipeline.set_state(Gst.State.PLAYING)
try:
loop.run()
except KeyboardInterrupt:
print("Interrupted by user")
if __name__ == "__main__":
import sys
if len(sys.argv) < 3:
print("Usage: python play_media.py <file_path> <num_loops>")
else:
print("note: the file_path should use absolute path")
file_path = sys.argv[1]
num_loops = int(sys.argv[2])
play_media(file_path)
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将脚本放到自动启动目录中, 一开机就自动启动并播放
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创建 auto_play.desktop 文件, 内容如下
[Desktop Entry]
Type=Application
Exec=/home/walter/test/script/playback.sh
Hidden=false
NoDisplay=false
X-GNOME-Autostart-enabled=true
Name[en_US]=/home/walter/test/script/playback.sh
Name=/home/walter/test/script/playback.sh
Comment[en_US]=
Comment=
- 复制上述文件到 ~/.config/autostart/ 目录中, 即可自动播放指定的视频
cp auto_play.desktop ~/.config/autostart/
本作品采用知识共享署名-非商业性使用-禁止演绎 4.0 国际许可协议进行许可。