AVC generally means H.264/AVC video compression, which is the codec responsible for compression, while the actual file format is usually a container like MP4, MKV, MOV, or TS that can hold AVC video along with audio tracks such as AAC, so people sometimes mix things up and label an MP4 as “an AVC file” despite the container defining the type; files ending in .avc or .h264/.264 usually contain raw AVC streams or custom exports that VLC may handle but often with weak seeking, incorrect duration, or no audio due to missing container-level indexing.
Some CCTV/DVR systems assign nonstandard file types though the video may still be standard, allowing a rename to .mp4 to work, while others need the manufacturer’s software to re-export; to identify the type quickly, open in VLC, check codec info, or run MediaInfo to see if it’s a normal container with audio, and if it shows as a raw AVC stream you typically wrap it into an MP4 container to improve seeking and compatibility without recompression.
A `.mp4` file is typically a full MP4 *container* that stores not just AVC/H.264 video but also timing data, indexes for smooth seeking, audio tracks, subtitles, and metadata, while a `.avc` file is often a raw H.264/AVC bitstream or device-specific export that lacks container structure; it can still play because frames exist, but players may struggle with smooth seeking since key structural info is missing.
This is also why `. If you want to learn more information on universal AVC file viewer take a look at our web site. avc` recordings often have silent-only output: audio wasn’t packaged or lives separately, whereas MP4 generally combines video and audio; plus, many CCTV/DVR systems output bizarre extensions, so a file might actually be MP4/TS but mislabeled and fixed by renaming, while others rely on proprietary wrappers needing vendor software; put simply, `.mp4` means a standard structured file, and `.avc` usually means something proprietary, which explains missing audio, limited seeking, and compatibility problems.
Once you’ve identified whether your “AVC file” is mislabeled, raw H.264, or proprietary, the correct approach becomes clear; if MediaInfo/VLC indicates a normal container like MP4—signs include “Format: MPEG-4” or smooth navigation—renaming the extension from `.avc` to `.mp4` is often enough, ideally after copying the file; if the file is a raw AVC stream (you’ll usually see “Format: AVC” with scant container details and awkward seeking), then remuxing it into MP4 without re-encoding is the usual fix, giving it the indexing and timing data it lacks.
If the footage originates from a CCTV/DVR or similar device using a custom container, the surest route is using the vendor tool to export to MP4 or AVI, since some proprietary formats won’t remux properly without an official export; in those cases you’re transforming a proprietary structure into a standard container, and if the file still fails—corrupted playback, no opening, wrong duration post-remux—it typically means incomplete data or missing index files, so the remedy is re-exporting or finding the required companion metadata.
