AVC most often refers to H.264/AVC, which is the compression scheme, not the container that packages audio, video, and metadata, and everyday formats like MP4, MKV, MOV, and TS simply wrap an AVC video track plus audio, causing confusion when people call the whole file “AVC” even though the container defines it; an extension such as .avc or .h264/.264 usually indicates a raw bitstream or proprietary output that VLC might open but with limited navigation, inaccurate length, or no audio since containers normally provide timing data and allow multiple streams.
Some CCTV/DVR systems output strangely named files even when the contents are standard, so a clip may be misnamed and work once renamed to .mp4, though some files are truly proprietary and require the vendor’s player to re-export; the quickest way to check is to open it in VLC, inspect codec details, or run MediaInfo to see if it’s a real container like MP4/MKV/TS with audio, in which case renaming often helps, while raw AVC streams usually need to be wrapped into an MP4 container for better compatibility and seeking without re-encoding.
A `.mp4` file generally provides a complete MP4 *container* with video, audio, subtitles, metadata, and timing/index data that ensures smooth playback, while a `.avc` file often signals a raw AVC bitstream lacking container features; it may still display video, but players can struggle with starting cleanly due to missing structural cues.
This is also why `.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 proper multimedia packaging, and `.avc` usually means something proprietary, which explains missing audio, limited seeking, and compatibility problems.
Once you’ve determined whether the “AVC file” is mislabeled, raw H. For more on AVC file format visit our own internet site. 264, or proprietary, you can pick the right fix; when VLC/MediaInfo shows a standard container—look for “Format: MPEG-4” or normal seek behavior—just renaming the `.avc` to `.mp4` often restores compatibility (after copying it), but if the file is a raw H.264 stream indicated by “Format: AVC” with sparse container details and erratic seeking, then the usual remedy is to wrap it into an MP4 container without re-encoding, adding essential timing and indexing data for proper playback.
If the file comes from a CCTV/DVR or a system with its own wrapper, the safest approach is usually using the vendor’s playback/export tool to create an MP4 or AVI, since some proprietary formats won’t convert smoothly without a correct export; in those situations you’re converting from a custom structure into a standard container rather than just renaming, and if playback is corrupted, won’t open, or the duration stays wrong even after remuxing, it often means the recording is incomplete or missing companion index files, so the real fix is re-exporting from the device or finding the required metadata files.
