AVC usually refers to H.264/AVC video compression, meaning it’s a way of
compressing video, not the file type, and everyday video files are really containers like MP4, MKV, MOV, or TS that simply carry an AVC-encoded video stream plus audio such as AAC, which is why people mistakenly call an MP4 an "AVC file" even though the true file type is the container; confusion grows when the extension is .avc or .h264/.264, since that often means a raw bitstream or a device-specific export that may play in VLC but lacks proper seeking, accurate duration, or audio because containers normally supply indexing and multiple tracks.
Some CCTV/DVR setups save recordings under odd extensions even when the data is perfectly normal, so simply renaming to .mp4 may fix playback, while other clips are proprietary and need the vendor tool to convert; the simplest way to identify the format is to load it in VLC, view codec info, or check with MediaInfo to see if it’s a true container (MP4/MKV/TS), and if it shows a raw AVC stream the typical solution is to wrap it into MP4 to get better compatibility and seeking.

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 accurate duration since key structural info is missing.
This is also why `.avc` files often include no audio: audio is usually stored separately or never bundled with the stream, while MP4 normally packages both video and audio together; additionally, some CCTV/DVR tools export nonstandard extensions, so a file may actually be MP4 or TS but mislabeled as `.avc`, and renaming it to `.mp4` can suddenly make it work, whereas other cases involve proprietary wrappers that need the vendor’s converter; in short, `.mp4` usually means properly indexed, while `.avc` often means a proprietary format, leading to missing audio, weak seeking, and compatibility issues.
Once you determine what kind of "AVC file" you have, the solution varies based on whether it’s mislabeled, raw H.264, or a proprietary export; when VLC or MediaInfo indicates a real container like MP4 (you may see "Format: MPEG-4" or normal seeking), simply renaming `clip. If you loved this article and also you would like to acquire more info about
AVC file software i implore you to visit our web site. avc` to `clip.mp4` often solves compatibility—just make a copy first; if the file is a raw bitstream instead, typically shown by "Format: AVC" with sparse container info and glitchy seeking, the fix is to wrap into an MP4 container without re-encoding, adding the indexing and timing structure raw streams don’t have.
If the file originated from a CCTV/DVR or another system using a proprietary wrapper, the most dependable method is running it through the vendor’s export tool to MP4 or AVI, because certain closed formats don’t convert reliably without a proper export; in those cases you’re converting from a special structure to a standard one rather than renaming, and if playback still fails, won’t open, or shows incorrect duration after remuxing, it usually signals corruption or missing sidecar/index files, meaning you must re-export from the source or retrieve the matching metadata.