Previewing a Clip

You can preview either the original source media file or the file with a setting applied to it. Source media files appear in the list as their filenames. Any settings that have been applied to the source media file are listed immediately below the file’s name and are indented to make it easier to identify them. Whether you choose to view the original source media file or the source media file with a setting determines which options you see in the Preview window.

Important: Settings you make in the Encoder pane and the Frame Controls pane cannot be previewed. Only the settings made in the Filters pane and Geometry pane can be previewed. See Transcoding a Portion of the Clip with the Preview Window for an alternative method of previewing Encoder pane and Frame Controls pane settings.

To preview a source media file
  1. Open the Preview window.

    Note: You can open your file into the Preview window in one step by double-clicking the source media file in its job in the Batch window.

  2. Do one of the following:

    • Choose a source media file from the Batch Item pop-up menu (identified by its filename).

      Figure. Batch Item pop-up menu.
    • Click the Batch Item selection buttons until the source media file appears in the pop-up menu.

    • Select the source media file in its job in the Batch window.

      Only the Source View button is active (and the Output View button is dimmed). This is because you selected a regular source media file, so you can only see the unadulterated clip—without the split screen divider or cropping bars.

  3. Choose a Preview screen size from the Preview Scale pop-up menu, or drag the Preview window handle to a size you like.

    This does not affect the display frame size of the actual output media file. That can only be set from the Geometry pane in the Inspector window.

  4. Click the Play button to preview the selected source media file.

    Source media files with markers already added, such as files from Final Cut Pro, will show the markers in the timeline. You can manage the markers if needed. See Working with Markers and Poster Frames for more information.

To preview a clip with an assigned setting
  1. Open the Preview window.

    Note: You can open the clip into the Preview window in one step, by double-clicking the target (that contains the setting) of a job in Batch window.

  2. Do one of the following:

    • Choose a setting from the Batch Item pop-up menu (the indented setting names, not the source filenames).

    • Click the Batch Item selection buttons until the clip with a setting appears in the pop-up menu.

    • Select the clip’s setting in its job in the Batch window.

    Both Source and Setting (Output) View buttons are active so you can switch between these two views. Because you selected a setting, you can use the split screen slider and cropping boundary in the Preview window.

  3. Click the Setting view button in the upper-right corner of the Preview window.

  4. Choose a Preview screen size from the Preview Scale pop-up menu, or drag the Preview window handle to a size you like.

    This does not affect the display frame size of the actual output media file. That can only be set from the Geometry pane in the Inspector window.

    Note: When you adjust the frame size of a setting (in the Geometry pane) while you are viewing it in the Preview window, the frame size may not resize accordingly. If this occurs, select Sample Movie or a different target from the Batch Item pop-up menu and then select this target again. It will display the correct frame size.

  5. Drag the split screen slider left or right across the top of the screen to move the split screen divider over more or less of the transcoded portion of the clip.

  6. Use the cropping boundary to adjust the display frame size of your output media file.

    Figure. Preview window showing cropping boundary.
  7. Check the results of your cropping by clicking the Source and Setting View buttons.

    Note: The more you reduce the clip image by cropping it, the larger the scale factor of the output image will be (as the framing geometry conforms to the settings of the output size ratio rather than to the source file settings). This effect is similar to zooming in on an image, which results in larger pixels and overall image degradation. So make sure that you don’t crop in so far that the image is enlarged past its original size relative to the original size of the frame.

    Figure. Preview window showing Source and Setting View buttons.
  8. Select the filter that you want to adjust and make changes as necessary.

    Note: The filter you select must have a checkmark next to it in the Filters list. Otherwise, the filter won’t be applied to the setting.

    Figure. Adjustments in the Filter pane of the Inspector window and results of those adjustments in the Preview window.
  9. If you want to make the display frame size of your output media file different from that of your source media file, open the Geometry pane in the Inspector window and choose a preexisting value from the Frame Size pop-up menu or enter different output size values in the relevant fields.

    Note: MPEG-2 is limited to preestablished display frame sizes based on MPEG-2 specifications. In this instance, all output size items are unavailable.

    Figure. Adjustments in the Geometry pane of the Inspector window and results of those adjustments in the Preview window.
  10. Click the Play button in the Preview window to view the clip.

    See About the Preview Window for more information about these settings.

Playing Dolby Digital Professional (AC-3) Files in the Preview Window

You can use the Preview window to play back Dolby Digital Professional (AC-3) files. Compressor includes a Dolby Digital decoder so that when you add an AC-3 source media file to a batch and play it, you are able to hear it using your computer’s current speakers. This includes everything from the built-in stereo speakers, which play a mixed-down version of the AC-3 file if it contains more than two channels, to a set of external surround speakers connected to a USB or FireWire output.

Important: Since Compressor is decoding the Dolby Digital audio file, you cannot use your computer’s optical output to preview Dolby Digital audio.

This feature is important if you are using the Dolby Digital Professional encoder since you cannot preview the encoder’s settings in real time in the Preview window. Instead, you can add the encoded AC-3 files to a batch and play them to verify that the encoder’s settings produced good results. See Transcoding a Portion of the Clip with the Preview Window for information on creating a short test clip for this purpose.