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How to record video using XCode Simulator
This article was auto-translated from Chinese. Some nuances may be lost in translation.
Using screen recording can be quite cumbersome, especially since you have to manually adjust the frame each time. So, I looked into whether it was possible to record video using the simulator, and I found that it actually is—and surprisingly simple too! You just need to use a command line instruction:
xcrun simctl io booted recordVideo --codec=h264 transition.mp4
After pressing ctl+c, the video file will be automatically generated. Just make sure that there are no files with the same name. Additionally, since I often upload my repros to GitHub, and GitHub doesn’t support video files, I use ffmpeg to convert them into GIF files:
ffmpeg -ss 2 -t 20 -i YOUR_VIDEO_NAME -vf "fps=10,scale=320:-1:flags=lanczos,split[s0][s1];[s0]palettegen[p];[s1][p]paletteuse" -loop 0 OUTPUT.gif
Then I’ll take my time to study the parameters of ffmpeg. In any case, this way I can convert video files into GIF files—awesome!
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