Difference between revisions of "MPEG"
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== Creating an MPEG File with VLC == | == Creating an MPEG File with VLC == | ||
To make an MPEG file, you need to: | To make an MPEG file, you need to: | ||
| − | * Pick a container (see [[# | + | * Pick a container (see [[#Container_formats|below]]) |
* Transcode the audio and video to formats able to be held in the container: in general this is the MPEG video and audio formats only. Check the [http://www.videolan.org/streaming/features.html compatibility information] in the official documentation, but be warned that while vlc allows any codec and mux, most other players support only a few combinations! | * Transcode the audio and video to formats able to be held in the container: in general this is the MPEG video and audio formats only. Check the [http://www.videolan.org/streaming/features.html compatibility information] in the official documentation, but be warned that while vlc allows any codec and mux, most other players support only a few combinations! | ||
Revision as of 15:24, 18 December 2006
MPEG refers to a set of standards created by the Moving Picture Experts Group. MPEG refers to several video, audio and container formats; see the full list at the Codec page.
An MPEG file is a file using an MPEG container (these are called mpeg1, ts, ps, and mp4 for MPEG-4).
Creating an MPEG File with VLC
To make an MPEG file, you need to:
- Pick a container (see below)
- Transcode the audio and video to formats able to be held in the container: in general this is the MPEG video and audio formats only. Check the compatibility information in the official documentation, but be warned that while vlc allows any codec and mux, most other players support only a few combinations!
MPEG-1 and 2
- Video codec: mp1v, mp2v
- Audio codec: mpga, mp2a, mp3
- Muxer: ts, ps, mpeg1
MPEG-1 is a video and audio compression format, used in Video CDs. It is compatible with a large number of software and hardware devices.
Here is an example of how to transcode an AVI into a portable MPEG-1 video from the command prompt
vlc file.avi --sout='#transcode{vcodec=mp1v, acodec=mpga}:std{access=file, mux=mpeg1,url=file.mpg}'
MPEG-2 is used in digital television and DVB. It is also used as the format for DVDs. The biggest advantage of this format over MPEG-1 is in its support for interlaced pictures; MPEG-2 can cleanly compress interlaced video, while MPEG-1 internally only works on progressive-scan video, so interlacing must be faked.
Here is an example of how to transcode an AVI into an MPEG-2 video from the command prompt
vlc file.avi --sout='#transcode{vcodec=mp2v, acodec=mpga}:std{access=file, mux=ps,url=file.mpg}'
Audio
MPEG-1 also contains several audio compression formats:
- mpga is MP1 or "MPEG-1 (Part 3) Layer 1"
- mp2a is MP2 or "MPEG-1 (Part 3) Layer 2"
- mp3 is MP3 or "MPEG-1 (Part 3) Layer 3"
Container formats
MPEG-2 specified 2 container formats, ts and ps. Containers hold video and audio information in them, and package them up so it can be sent over a network or stored on disk.
- ts (Transport Stream) should be used to store or send data where data loss will probably occur, such as over a network.
- ps (Program Stream) should be used to store or send data where data loss is not likely, such as on a DVD.
Both ps and ts can transport MPEG-4 Video, but only ts can send MPEG-4 Audio. In addition, MPEG-4 specifies it's own container format, mp4 (see MPEG-4)
TS
ts
|
VLC can encode and decode this container. The module name to use at the command line is ts. |
Module options
- --ts-extra-pmt (string)
- Extra PMT. Allows a user to specify an extra pmt (pmt_pid=pid:stream_type[,...]).
- --ts-es-id-pid" (boolean)
Set the internal ID of each elementary stream handled by VLC to the same value as the PID in the TS stream, instead of 1, 2, 3, etc. Useful to do '#duplicate{..., select="es=<pid>"}'."). Default is true.
- --ts-out (string)
- Fast UDP streaming. Sends TS to specific ip:port by udp (you must know what you are doing). Default off.
- --ts-out-mtu (integer)
- MTU for out mode. Default 1500.
- --ts-csa-ck (string)
- Control word for the CSA encryption algorithm.
- --ts-csa-pkt (integer)
- Default: 188
- --ts-silent (boolean)
- Supresses complaints for encrypted PES. Default false.
- --ts-dump-file (file name)
- A filename do dump ts into.
- --ts-dump-append (boolean)
- Append data to the dump file. Default is false, which overwrites the file.
- --ts-dump-size (integer)
- The size of the buffer for reading/writing an integer number of packets. Default: 16384 bytes.
Accepted video codecs
Accepted audio codecs
Accepted subtitle codecs
PS
ps
|
VLC can encode and decode this container. The module name to use at the command line is ps. |
Module options
- --ps-trust-timestamps (boolean)
- Turns on or off trusting the timestamps in the file. Set as false to work it out from the bitrates. Default true.
Accepted video codecs
Accepted audio codecs
Accepted subtitle codecs
MPEG-3
A largely unused audio and video compression format.
- Note that the amazingly common MP3 audio files are actually MPEG-1 Layer 3 audio, not MPEG-3.
MPEG-4
See MPEG-4.
Source code
- modules/mux/mp4.c (output muxer)
- modules/demux/ps.c (input demuxer)
- modules/demux/ts.c (input demuxer)
- modules/demux/ps.h (input demuxer)
