It never fails that you’ve just spent good time exporting your film from your NLE, run it through a compression program to turn it into a client friendly H.264 file and a last minute audio tweak or music change comes through. Save time re-exporting and re-rendering with this simple method of replacing the audio in your quicktime file. This is particularly useful if you’re a composer or mixer appending new audio to a file for client review.
Step 1 – Open Your Files
Quicktime Player Pro 7 may or may not be installed on your system but if you’re used to doing much post production you’ll probably already have it. If not in different OSX versions.
Open your original audio & video file in QTPro7 by right (ctrl) clicking and pressing ‘open with…’ and then do the same with your new audio file.
Step 2 – Remove Original Audio
Select the original audio & video file and press CMD+J to open up the movie properties for the file (or go to Window > Show Movie Properties) You should see a video track, audio track and timecode track listed in the top section and in the resources tab where that audio track, video track and timecode track are originating from. Select the audio track and delete it. You can either hit backspace on your keyboard or the delete button in the top left of the window.
Step 3 – Copying and Pasting
Select the new audio file and press CMD+A to select it all. Press CMD+C to copy it. Now select the original video file and press CMD+ALT+V to add it to the movie file (you can also do all that from the Edit menu if you prefer). Notice that the source for the Sound Track in the properties window of the video and new audio file is New Audio.aif. It is important that the ‘playhead’ in the video file is at the very start of the file as the audio will paste in from wherever it is placed.
Step 4 – Save As…
For the final step simply press Shift+CMD+S (File > Save As…) to save the file as a new audio and video file without having to re-render your H.264 video. Make sure you have ‘Save as self-contained movie’ checked so that Quicktime collects up the ‘external’ new audio you pasted in. Quicktime will quickly save and your file is updated with the new audio.