How to Fix Truncated MP4 File (Complete Repair Guide for Incomplete Videos)

Part 1. What Does "Truncated MP4" Mean?

Before we move towards how to repair truncated MP4, let's first look at its core meaning and symptoms:

1. MP4 File Truncated Meaning

Typically, a truncated MP4 file is an incomplete video due to an interruption during recording or downloading. It lacks the essential metadata that's necessary for media players to interpret the video, resulting in a truncated video online.

2. Truncated vs. Corrupted: What's the Difference

People often confuse a truncated MP4 with a corrupted one, but they are two different things. Here's an overview

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3. How to Tell If Your MP4 Is Truncated (Typical Symptoms)

Some common symptoms of a truncated video include the MediaInfo showing "IsTruncated: Yes" or the VLC error "moov atom not found.” In addition, you cannot fast-forward to a later part of the video, abruptly freeze it, or adjust its length or duration.

Part 2. Why MP4 Files Become Truncated or Incomplete?

If you have a truncated MP4 file and wonder why it happens, here are some major reasons behind it:

• Power Failure: Sometimes, the camera battery dies during a video before you finalize it, resulting in an incomplete file.
• Storage Issues: If the device runs out of space, it'll only save the partially written, truncated video. See: How to Fix Hard Drive Full and Video Corrupted Issue.
• Network Issues: Internet issues during a browser download or the removal of an SD card while the data is being transferred can also require you to fix truncated MP4 free.

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⚡ Part 3. Best Way to Fix Truncated MP4 Files with Professional Video Repair Software (Step-by-Step)

To repair incomplete MP4 and restore truncated MP4, you need a reliable tool such as 4DDiG Video Repair. It works as a video repair as well as an AI enhancer tool, which can boost the quality of your content up to 8k resolution. The platform is completely safe and secure, and it takes around 1 minute, sometimes less, to fix an incomplete MP4. Here's a step-by-step guide on its usage:

• Open 4DDiG File Repair on your device and choose File Repair. Click Add Videos to upload all the truncate videos directly or use the drag-and-drop feature.

  

• Click “Repair All” and wait until the tool is doing its job.

  

• Once the repair is complete, preview the videos and then Save All.

  

Part 4. Other Feasible Ways to Repair Truncated MP4 Videos (4 Options)

To repair an incomplete MP4 file, you can also use other methods such as Untrunc, FFmpeg, and VLC. Here's a detailed explanation:

Method 1: Using Untrunc

Untrunc is a video repair tool that excels at fixing truncated MP4 files. It's an open-source command-line tool that needs to be compiled. However, you can use the GUI version that's suitable for Windows, and the steps for that are:

• Go to the Untrunc’s GitHub page and download the untrunc_x64.zip.

• Extract the file and then run untrunc-gui.exe.

• Now, click the truncated file option and find and select the corrupted MP4 file.

  

• Click the reference file button, search for the healthy file video, and double-click it.

  

• Tap “Repair” and the process will start.

  

• Save the repaired copy in its original location.

Method 2: Fix Truncated MP4 Files with FFmpeg

FFmpeg quickly repairs MP4 videos by segregating video and audio streams and then combining them into a new container. It also fixes metadata and inconsistent codecs so the video appears complete. The following are the steps for that:

• Visit the FFmpeg download page to get the tool.

• Open the File Explorer and create a FFmpeg folder on the primary storage drive.

• Get a reference video and place both the corrupt and reference videos in the “/ffmpeg/bin” directory.

• Run command one recover_mp4.exe valid.mp4 --analyze.” This will recover metadata from the reference video.

• You'll now see two options; select the second one to run the 2nd command. It looked like “recover_mp4.exe corrupt.mp4 recovered.h264 recovered.aac.” The video and audio streams of the truncated videos are split into separate files.

• Now the final command “ffmpeg.exe -r 30 -i recovered.h264 -i recovered.aac -bsf: a aac_adtstoasc -c:v copy -c: a copy recovered.mp4” directs FFmpeg to compile both extracted audio and video into a repaired MP4 file.

Method 3: Using VLC to Repair & Play Truncated MP4 Videos

We are all aware of VLC and have even used it at some point, but do you know it can also fix incomplete MP4s? All you have to do is rename your MP4 file using the AVI extension and follow these steps:

• Open VLC and go to Tools.

• Click Preferences and then “Input/Codecs”.

• Switch the drop-down option for damaged or incomplete AVI files to “Always fix”.

  

• Tap Save and then play the file.

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Method 4: Fix Truncated Video Online (with 4DDiG Online Free Video Repair Tool)

If you are looking for something free to fix truncated MP4, 4DDiG Online Free Video Repair is the ideal solution. You can simply visit the site, upload your incomplete videos, and click on repair. Soon you'll get fixed videos without any compromise on the quality.

Other than repairing, 4DDiG also restores the sound, eliminates flickering issues, and even clears blurry, pixelated videos. However, the minimum file size is 3 MB, and the free version only offers 3 uploads per day.

Part 5. How to Prevent Truncated MP4 Files in the Future

Know that avoiding truncated MP4 files in the first place is way better than fixing them later. Here are a few suggestions that you should follow:

• Record in MKV format rather than MP4 to avoid loss if recording is interrupted.
• Enable auto-remux in OBS Studio to safely convert MKV to MP4.
• Always use a stable power source to prevent sudden power losses and shutdowns.
• Stop all recordings properly, rather than force-closing the software or device.
• Don't record directly to external drives; save the recordings to internal storage first.
• Have enough free disk space, because if the storage fills up mid-recording, the video will be truncated.

Conclusion

The whole process to fix truncated MP4 files becomes easier with 4DDiG Video Repair. It's available for free and takes seconds to convert damaged videos into high-quality ones.