Specify QuickTime compression settings

1. In the Render Queue panel, click the underlined name of the output module.
2. For Format, choose QuickTime Movie.
3. Click Format Options in the Video Output section.
4. In the Compression Settings dialog box, choose a compressor.
   Note: Set the color depth in the Compression Settings dialog box instead of in the Output Module Settings dialog box. This setting ensures that non-Adobe plug-ins receive color depth information from After Effects. See step 8.
5. Select a Quality level from Least to Best.

   The Quality control specifies the spatial compression of the movie, which compresses the data in each frame of a composition. Higher quality produces better image quality but results in a bigger movie file. This quality setting is unrelated to the quality setting for each layer in After Effects.

   Note: (Mac OS only) If you intend to use key frames in the movie, hold down Option and adjust the Quality slider to control the temporal compression of the movie. Temporal compression compresses a movie by comparing successive frames and keeping only changed data. High temporal quality maintains smoothness of motion. Low temporal quality tends to produce jerkiness of motion because a pixel doesn’t change unless the difference between frames is great.
6. If you want the smallest possible files, and your compressor choice allows for a key frame rate, select the box and enter a number in the Key Frame Every box. Generally, you should enter a number equal to the frame rate. For example, if you set a frame rate of 30 fps, enter 30 in the Key Frame box.
   Note: If you are going to use the resulting movie in another After Effects composition, enter a small value (less than 5) in the Key Frame Every box or deselect the Key Frame Every option.

   In QuickTime terminology, the term key frames is different from the change-over-time keyframes placed in the After Effects Timeline panel. In QuickTime, key frames are frames that occur at regular intervals in the movie. During compression, they are stored as complete frames. Each intermediate frame that separates them is compared to the previous frame, and only changed data is stored. Using key frame greatly reduces movie size and greatly increases the memory required to edit and render a movie. Shorter intervals between key frames enable faster seeking and reverse playback, but can significantly increase the size of the file.

7. Click OK.
8. If your compressor choice supports different image color depths, choose the appropriate color depth in the Output Module Settings dialog box:

   • Choose Millions Of Colors+ if you want 24-bit color quality and you want your composition background to be transparent (to include an alpha channel). The composition background color is disregarded. Only Animation and None can support the Millions Of Colors+ color depth.

   • Choose Millions Of Colors if you want 24-bit color quality but want to include your composition background color (no alpha channel).

     Note: Color depth settings of Thousands Of Colors or lower may cause banding and dithered images.
9. Specify other settings in the Output Module Settings dialog box, and then click OK.

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