Once you've uploaded a video to your YouTube account, you have two options for generating subtitles for the video: You can use the CaptionTube web app that Google has created, or you can upload a transcript you make yourself and use Google's speech recognition technology to automatically assign the right times to each caption. In either case, you'll end up with a text file that you can edit to make corrections if need be, and viewers will be able to either read the captions in their native language or translate them on the fly when watching your video.
CaptionTube
First, direct your browser to the CaptionTube website and you'll find a well-realized web application for importing videos, adding and timing captions for them, and exporting the captions however you want them. You'll have to sign in with your Google account. After you've done that, you'll have two options for importing a video; you can either import a list of all the videos on your account, or you can specify the web address for a public video.
Whichever way you go, the path to importing the video you want is a pretty easy one. Click the edit button next to your video once it's been imported to get to the caption creation screen.
Click the "Add Caption" button and then type in what you want your caption to say. Pick a start time in seconds and milliseconds, then specify how long the caption will stay on the screen. Once you save it, it will appear in a time line at the bottom of the app so you can see it in relation to other captions. When you've added all your captions, click publish.
Choose the "Download to My Computer" option (either file format will work) and CaptionTube will give you a text file that you can tweak as needed and add to your videos. To add the file to your video, go to your YouTube My Videos page, find your video, and click the "Caption" button to reach the caption options. Click the button to add new captions, browse to find the file CaptionTube gave you, check the "Caption file (includes time codes)" option, and hit "Upload File." That ought to do it.
Captions By Voice Recognition
The CaptionTube method used to be the only easy way to add captions to your video, but Google introduced a new one towards the end of 2009: captions generated by voice recognition. Google's computers use the same technology that powers Google Voice to listen to your video while reading your transcript, then automatically generate captions at the right times.
First you'll have to watch your video and create your own simple transcript of the words spoken in the video. This should be pretty easy; no special formatting is required. Just save it as a basic text file using Notepad if you're a Windows user or TextEdit if you have a Mac.
After you've saved the file, go to your YouTube My Videos page, find your video, and click the "Caption" button to reach the caption options. There you can click the button to add new captions, browse to locate your new text file, and select the "Transcript" option. Hit "Upload File" after that.
