Captioning for Quicktime
Creating the Quicktime Text Track

Article Contents

  1. Page 1: Introduction to Captioning for Quicktime
  2. Page 2: Creating the Caption File
  3. Page 3: Creating the Quicktime Text Track
    1. Preparing the Caption File
    2. Making the Conversion
  4. Page 4: Adding Captions to a Quicktime Movie
  5. Page 5: Using SMIL to Add Captions to Quicktime Movies
  6. Page 6: Adding Quicktime Content to a Web Page

Preparing the Caption File

A Quicktime text track is a Quicktime movie file that contains our caption information.

Important

A Quicktime text track file is not necessary if you want to use SMIL to control the layout of your movie. The caption information can be kept within the text file and combined with the video on-the-fly when the movie is viewed. If you want to combine the Quicktime text track and the video into one stand-alone Quicktime movie, then you must have Quicktime Pro and follow the instructions below. If you plan on using SMIL to combine the captions and video, you may skip these instructions and continue on to the section in this chapter titled Using SMIL to Add Captions to Quicktime Movies.

Creating the Quicktime text track involves taking our caption text file (whether generated in MAGpie or manually using a text editor) and creating a Quicktime movie with it. A Quicktime text track is just a Quicktime movie that displays text based on information from the caption file. If you are going to use SMIL, you do not need to convert your caption file to a Quicktime text track. SMIL allows the player to convert the caption file "on-the-fly". Understanding this process is still valuable, will allow you to test your caption file, and will be necessary if you are not using SMIL.

Open the caption file you created in the previous step or that was created by MAGpie. MAGpie may name the file Streamx.txt (where x is some number) and save it in the MAGpie folder. The file should open with your computer's default text editor (usually Notepad on Windows and SimpleText on Macs). Make sure everything is the way you want it to be. Set the preferences at the top of the file to the correct settings. MAGpie users will need to set the width and height values to the appropriate settings. You will usually want the width to be the same as the width of your video clip. You can determine this width by opening the video clip in Quicktime, selecting Movie > Get Movie Properties, and changing the right hand drop–down menu to display Size. You should see something like this - Normal: 320 x 240 pixels. The first number (320) is the width of your movie; the second number is the height.

Making the Conversion

As soon as everything looks right, save your caption text file. In Quicktime Pro - external link, under the File menu, select Import and browse to where the caption text file has been saved. Select the file and press the Convert button.

Screenshot showing Import dialog box with the caption file selected.

Quicktime will now read the information in your text file and create a Quicktime text track movie. If you get an error message, it is because there is probably a mistake in the caption file. Review your settings and timecode and make sure everything is correct. If even one character is out of place, Quicktime will be unable to read the file.

The next screen asks where and with what name you want to save your new Quicktime text track movie, but before you save it, select the Options button.

Screenshot showing Text Import Settings window.

This window allows you to set or change settings for the text track movie. It should display the settings in your caption file (though it always wants to change the font to Helvetica for some reason). Best-Fit Width and Height would make the caption movie only as big as it needs to be. Because we are going to combine these captions with our video, it is best to specify pixel width and height for our text track, so it fits well with our video. You can modify any of these settings to meet your needs.

When you're done, select OK to return to the Save converted file as window. Quicktime wants to save the file as yourfilename.txt.mov. Remove the .txt part from the filename, so your file will be saved as something like captions.mov. Make sure that it has the .mov file extension.

Note

If you are captioning several movies, decide on a consistent naming convention for your files. For example, use wizard_of_oz.mov for the video file, wizard_of_ozCap.txt for the caption file, and wizard_of_ozCap.mov for the text track movie. This makes it easy to know which caption files go with which video file.

Once you have entered the correct filename, select the Save button. The Quicktime text track movie will now open. If you get a "File is locked" error, close Quicktime, reopen the program, and then import the file again. Quicktime cannot save to a text track file that is already open.

Quicktime window with captions playing.

Play the movie and make sure everything looks the way you want it to and that no captions are cut off at the bottom of the movie. I suggest leaving room at the bottom because some computers display the text larger than others, and the captions may be cut off at the bottom. If there are any errors, go back to your caption file or MAGpie and make the changes, save the file, and go through this process again.

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