webm格式转换mp4
There's an upcoming Mozilla trip to Hawaii on the cards and, in trying to be a good family man, I'm bringing my wife and two young sons. Glutton for punishment? Probably. Anyways, I've been feverishly downloading cartoons from YouTube using youtube-dl to put onto our new iPad to keep my oldest son occupied during the long flight.
Mozilla即将进行夏威夷之旅，准备成为一个好家庭男人，我要带上我的妻子和两个小儿子。 贪吃惩罚？ 大概。 无论如何，我一直在疯狂地使用youtube-dl从YouTube下载卡通作品，并将其放到我们的新iPad上，以使长子在长途飞行中不被占用。
It seems as though YouTube preserves the original video format, since sometimes youtube-dl provides a webm and other times a mp4. Since mp3s are iOS' best friend, I've needed to convert the webm files to mp4. The following ffmpeg command will make that happen:
YouTube似乎保留了原始的视频格式，因为有时youtube-dl提供了webm，而其他时候提供了mp4。 由于mp3是iOS最好的朋友，因此我需要将webm文件转换为mp4。 以下ffmpeg命令将实现此目的：
ffmpeg -i "Spider-Man.webm" -qscale 0 "Spider-Man.mp4"The qscale 0 directive instructs ffmpeg not to adjust quality of the video during conversion. And with this conversion I can now properly transfer the videos onto my iPad.
qscale 0指令指示ffmpeg在转换过程中不要调整视频质量。 通过这种转换，我现在可以将视频正确地传输到我的iPad上了。
Check out my media tutorials for more magic when it comes to video, audio, and images. You're sure to learn a few tricks along the way.
查看我的媒体教程 ，以获取有关视频，音频和图像的更多魔术。 您一定会学到一些技巧。
翻译自: https://davidwalsh.name/convert-webm-mp4
webm格式转换mp4