There are many reasons to use something other than After Effects for batch converting files. It simply isn’t set up for it, and many standalone compression apps simply do a better job. Occasionally it is the right tool for the job, so I am going to show you how to batch convert files in After Effects.
For advanced AE users, here’s the overview:
1) we are going to create presets for our render settings, output module, and destination.
2) Then we are going to set those as our defaults for new renders.
3) Finally we are going to use a neat trick to convert video files to comps and add them to the render queue all in one fell swoop.
STEP ONE – create presets
For this example I will be showing how to add interlacing to files with AE, but feel free to substitute your settings for mine if you are doing a different task.
Go to Edit > Templates > Render settings.
Type a name into the box, Hit the “Edit…” button and put in your settings. This menu is largely for frame and field work so if you don’t need to change anything from the defaults, you can skip this step.
Now select your new preset as the default movie preset from the top drop down menu.
Now go to Edit > Templates > Output module.
Create a new output setting and make it the default, just like before.
Lastly, create a blank comp, add it to the render queue, and set the “Output To” field to your intended destination. Then delete that render task and comp.
Now we are ready for the last step. Drag all of your input files into the project window. Select them all in that window and drag them down onto the “Create A New Composition” button. It is the filmstrip icon to the right of the Folder icon at the bottom of the Project window. You will get this dialog box.
Click on the “Add to Render Queue” Option and hit OK.
Now everything is all ready to go. Double check that your render settings, output module, and output directory have been applied to all of the render tasks. Save the AE project, and hit Render!