AN OLD FILE AND A CAR SCREEN
Play an AVI on iPhone and CarPlay. And the WMV, the TS and the VOB beside it.
To play an AVI on iPhone and CarPlay, import it from Files and open it; Dashow routes .avi to its additional decoding path instead of the system decoder. The same route takes .wmv, .flv, .ts, .mts, .m2ts, .mpg, .mpeg, .vob, .webm and .ogv, so the file goes in as it is.
- 01
Eleven older extensions take the additional decoding path, so an AVI goes in unchanged.
- 02
A transport stream reads from any point, so a .ts missing its start still plays.
- 03
The extension picks the decoder; the codecs inside decide the picture and the sound.
How it works
Your quick start
- 01
Import it from Files
Choose Add, then Files, and pick the .avi, .wmv or .ts; Dashow keeps its own copy and your original stays where it is.
- 02
Open it and watch
Tap the video in Saved Videos; the app routes by extension, so you never pick an engine.
- 03
Read the media details
Details lists duration, display dimensions, codecs, file size and the embedded title.
- 04
Or play it off the NAS
A video reached over SMB takes the additional decoding path whatever its extension, so the .avi on the share needs no copy first.
Nothing is wrong with the AVI.
You tap the file in Files, a preview sheet appears, and nothing plays. The file is intact. An .avi from a burned disc, a .wmv exported by an old work tool and a .ts pulled off a tuner all behave the same way, because the system decoder on iOS opens a short list of containers and these are not on it.
Apple’s own help page for a media file that does not open says to try another app, and declines to publish the list of what plays. That list is the useful part. Dashow reads the extension, sends an AVI down a second decoding path of its own, and the same path takes every other container here.
AVI, WMV, TS and VOB are one problem, not eleven.
Eleven extensions take that same route: .avi, .webm, .flv, .ts, .mts, .m2ts, .wmv, .mpg, .mpeg, .vob and .ogv, alongside .mkv. Each is a container, a wrapper around a video track, one or more audio tracks and sometimes subtitles. The extension names the wrapper. What the wrapper holds is a separate question, and that is what decides the picture.
So the extension is a routing hint rather than a promise. It tells Dashow which decoder to try first and says nothing about whether the video and audio tracks inside will each decode. That is why two files carrying the same extension can behave differently, and why a page listing formats without saying so tells you half of it.
Bring the AVI in from Files and open it.
Choose Add, then Files, and pick the .avi. Dashow imports it as a managed local copy and leaves your original where it was. The video lands in Saved Videos, sortable by date, title or viewing, next to everything else you have brought in. Open it the way you would open an MP4. You never choose a decoder.
Details reports what the container actually holds: duration, display dimensions, codecs, file size and the embedded title. Read it once for a file that surprises you. An old .avi and a tuner’s .ts can both open on the same path and still carry different video and audio codecs, and the codec line is where you see which you have.
Why a .ts or .m2ts behaves differently from an AVI.
A transport stream was designed to be broadcast, so it repeats its structural information across the file instead of writing it once at the front. A player can join at any point and read what follows. So a .ts from a tuner, a .mts from a camcorder card or a .m2ts from a disc opens even when the recording lost its beginning.
The same design is why HLS cuts a live stream into transport-stream segments, each playable on its own; RFC 8216 specifies that arrangement. An .avi is built the other way round, with a single index describing the whole file. An interrupted copy is a file whose map no longer matches it. An interrupted .ts is simply shorter.
A .vob or .mpg off a disc arrives in pieces.
A DVD does not hold one film file. It holds a VIDEO_TS folder of numbered .vob parts, and a two-hour feature lands as VTS_01_1.VOB, VTS_01_2.VOB and VTS_01_3.VOB. Copy that folder across and you get three videos, each starting mid-scene. Nothing is broken. The film was stored in segments before you touched it.
Each part plays on its own once imported, through the additional decoding path like any other .vob or .mpg. Play them in numbered order. A tuner capture can split the same way, one file per recording session. If the parts sit on a share, Dashow reads them over SMB with no copy step, since anything reached that way takes the same path.
What the extension does not tell you, and where to go next.
An extension routes the file. It does not describe the tracks inside, which is where the surprises live. A video that plays with a moving progress bar and silence is carrying an audio track the system decoder will not open, often a surround format such as AC-3, E-AC-3 or DTS. The Audio & Subtitles menu lists what the file has.
This page covers the older containers. MKV has its own guide, because a Matroska file carries chapters and subtitle tracks that change what you can do once it opens. An old .avi or a .vob ripped years ago streams from nowhere; it lives on the device, which makes it right for a parked charging stop with nothing to buffer. The full routing table sits in the formats hub.
Where each old extension comes from
| Extension | Where it usually comes from | What to know |
|---|---|---|
| .avi, .wmv, .flv, .ogv | An old download or a work archive | Routes to the additional decoding path |
| .ts, .mts, .m2ts | A tuner recording or a camcorder card | Same route, and readable from any point |
| .mpg, .mpeg, .vob | A DVD rip | Same route, often split across several files |
| .mkv, .webm | A re-encoded film or a web download | Same route; MKV has a guide of its own |
