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Rotoscoping is a great way to isolate subjects from your footage as if they were shot on a green screen. This is a tedious and time consuming process of tracing the outline of the subject frame by frame, but luckily the rotobrush tool in Adobe After Effects [AE] makes the process much faster. While the Roto Brush will not be as precise as manual rotoscoping, it is nonetheless a useful asset to your Adobe AE toolbox.
- Make sure that the preview resolution is set to “Full” so that you can clearly make out the details of your subject, which will ensure the accuracy of your rotobrushing.
- Double-click your footage to open the layer panel. At the top of the layer panel is the Roto Brush icon. Click the icon, and the selection cursor will have turned into the Roto Brush cursor.
- Starting at the beginning of your composition, use the rotobrush to paint the subject. The software will begin to detect the outline of your subject and will trace a pink line in the selected area.
- The software will never trace the outline with perfect accuracy. Zoom-in to the areas where there is too much or too little selected, and begin editing with the brush. Hold the Alt button on the keyboard to switch the cursor to subtract [red]. This is used for deleting selections and chiseling difficult areas like between the subject's feet. Vary the size of the brush using Alt+Command to go into smaller areas.
- 5 Monitor the selection. After you have a satisfactory trace in the first fame, the software will automatically propagate the brush, as the video progresses, to follow the path of the subject - but it will make errors that require intervention. Using the arrow keys, move the video ahead frame by frame, watching the outline to make sure it is continuing to track the shape of the subject.
- Once you come across a frame where the outline is no longer accurately tracing the subject, you must manually fix the errors with the Roto Brush. HINT: Toggle different views to help rotoscope more accurately. Once you fix an erroneous frame, the software will save the new information and you can continue forward checking the rest of the frames. Continue this process of editing the automated brush errors until you reach the end of your composition.
- Twirl down in your layer panel under “Effect Controls” to “Roto Brush & Refine Edge”. From here, you can select options to adjust your rotoscoped footage. From here, you can adjust the feather to make the outline softer, reduce chatter to smooth out rough outlines, and much more. Edit and keyframe these settings to achieve your desired result.
- Now that you have an isolated subject, you can make many interesting effects in your production. By duplicating the original footage, you can create depth by having 3D particles appear to flow both in front and behind your subject, or you can completely move the subject into a different background as if the subject was filmed with a green screen – there are lots of special effects possibilities with rotoscoping.
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- Aim to skip ahead 3 frames at a time to be more efficient in your edits to the selection area
- Duplicate the footage used for your rotoscope and put it in a different layer to make a mask of your subject to which effects can be applied
Enable alpha channel when rendering to make sure the rotoscoped subject does not have an unwanted background behind it
Wondering why After Effects won't render? We're here to help! Read on to discover the top causes of After Effects not rendering and how to fix them.
After Effects is a powerful compositing application for creating motion graphics and visual effects. However, encountering issues with rendering can be frustrating and disrupt your workflow. In this blog post, we will explore common reasons why After Effects may fail to render, provide practical solutions to fix the problem and address frequently asked questions related to rendering issues.
Why Is After Effects Not Rendering?
There are several reasons why After Effects may encounter problems when attempting to render a composition. Understanding these causes can help you troubleshoot and resolve the issue more effectively. Here are a few common factors:
Insufficient Memory
After Effects requires a considerable amount of memory to perform rendering tasks. If your computer’s RAM is insufficient, it can lead to rendering errors or crashes. Complex compositions with numerous effects and high-resolution assets may particularly strain system resources.
Software or Plugin Compatibility
Incompatibility between After Effects, operating system updates, or third-party plugins can lead to rendering problems. This can occur because outdated plugins or older After Effects versions may lack the necessary compatibility to execute the rendering process smoothly.
Unavailable or Corrupted Media
If After Effects cannot access or read the necessary media files [footage, audio, images] within the composition, it will encounter rendering issues. Missing, relocated, or corrupted media files can prevent successful rendering.
Incorrect Output Module Settings
Incorrect output module settings can cause After Effects to fail to render a composition correctly. Incorrect file formats, codecs, or other settings may result in incomplete or problematic output files.
After Effects Not Rendering: Common Causes & How to Fix It
Let’s look at the most common causes of After Effects render crashes and some solutions for how to fix them.
1. Check System Resources
Ensure that your computer meets the minimum system requirements for After Effects. Allocate more memory [RAM] to After Effects by closing other unnecessary applications – especially other Adobe or editing apps.] Consider upgrading your hardware or rendering on a more powerful machine for resource-intensive projects.
2. Verify Output Module Settings
Double-check the output module settings in the Render Queue panel. Ensure the file format, codec, resolution, and other settings are appropriate for your desired output. Experiment with different settings or use the default options if you’re unsure or are experiencing crashes.
One fix for frequent crashes is rendering your composition as a PNG sequence, rendering each video frame as a PNG image. This will store all the rendered frame images in your output folder until the frame After Effects crashes, from which you can try rendering again.
3. Confirm Media Availability
Verify that all media files used in the composition are accessible and correctly linked. Check for missing or relocated files and relink them within After Effects. If files are corrupted, replace them with backups or fresh versions. Sometimes a faulty hard drive can cause issues, so store your video media and assets on solid-state drives [SSDs] whenever possible.
4. Update Software and Plugins
Ensure you are using the latest After Effects version by updating any plugins or third-party software you rely on. You can resolve most compatibility issues using up-to-date software, so check for updated versions on the Creative Cloud desktop app. If you are still encountering errors, try rolling back to a previous After Effects version, or experiment with the beta versions of After Effects available on the Creative Cloud app.
5. Reset Preferences
Sometimes, corrupt preferences can cause rendering problems. Resetting After Effects preferences to their default state can help resolve issues. Hold down the Ctrl+Alt+Shift [Windows] or Command+Option+Shift [Mac] keys while launching After Effects to reset preferences.
6. Render Multiple Frames Simultaneously
Try enabling the “Render Multiple Frames Simultaneously” option in the preferences. Navigate to Preferences > Memory & Performance. This allows After Effects to use multiple CPU cores, significantly speeding up the rendering process. However, if this setting is already on and you are experiencing crashes, turn it off to see if that fixes the issue.
7. Pre-render Complex Compositions
For compositions with multiple effects and heavy processing requirements, consider pre-rendering sections of the composition. This involves rendering the problematic parts separately and importing the pre-rendered footage into the main composition. This solution can’t be understated enough. I‘ve often used this method to solve After Effects rendering crashes in real-world applications.
FAQs for After Effects Not Rendering
Let’s quickly reiterate some of the most frequently asked questions regarding After Effects rendering issues and look at where you can troubleshoot to find solutions.
1. Why does After Effects freeze or crash during rendering?
Insufficient system resources, including memory and processing power, can cause freezing or crashing during rendering. Ensure your computer meets the minimum requirements and optimize your composition settings accordingly. Make sure After Effects and 3rd-party plugins are up to date. Also, try rendering sections of your composition and video as a PNG sequence to help minimize rendering issues if crashes occur.
2. How can I reduce render times in After Effects?
Several techniques can help reduce render times, such as using proxies, optimizing composition settings, and rendering in the background using multiple cores. Turning off unnecessary effects or using third-party plugins designed explicitly for faster rendering can also help improve efficiency. Using faster hardware [such as GPU and CPU] will enhance your After Effects render time, as well as using separate SSDs for your media and memory cache.
Also, enable the Preview setting “Cache Frames When Idle.” Navigate to Composition > Preview > Cache Frames When Idle.
3. What should I do if After Effects encounters an error while rendering?
If you encounter an error during rendering, take note of the error message or code from After Effects. Try troubleshooting the specific error by searching for solutions online or consulting the Adobe After Effects community forums. You can often resolve errors by updating software, checking system resources, or adjusting project settings.
4. Can I continue working on my project while rendering in After Effects?
Yes, After Effects allows you to continue working on your project while rendering. However, keep in mind that rendering can consume system resources, which may affect the overall performance of the software. It’s advisable not to work simultaneously to help alleviate rendering issues – working while rendering opens the door to more problems and bugs.
5. Why does After Effects render a black screen or produce an empty output file?
This issue can occur for various reasons, such as incorrect output module settings, missing or corrupted media files, or incompatible codecs. Double-check your output settings, ensure all media files are correctly linked, and verify the codec compatibility. If the problem persists, consider rendering to a different format or seeking assistance from the After Effects community forums. Also, try rendering to a different codec or file format to check if the output is still an empty or black-screen file. If it isn’t, it’s likely an issue with the first codec you tried to render to.
6. How can I troubleshoot if After Effects renders slowly?
Factors like high-resolution assets, complex effects, or insufficient system resources can cause slow rendering. To troubleshoot, optimize your composition settings, use proxies for high-resolution assets, allocate more memory to After Effects, or render on a more powerful machine. You can also consider pre-rendering sections of the composition to alleviate processing demands. If you’re performing minimal editing and compositing, you may be better off rendering in Premiere Pro. Check out our blog post on After Effects vs. Premiere Pro to learn about the pros and cons of using each app for your video!