FFmpeg

FFmpeg

FFmpeg running on Microsoft Windows
Original author(s)	Fabrice Bellard
Developer(s)	FFmpeg team
Initial release	December 20, 2000 (2000-12-20)[1]
Stable release	3.0 (February 15, 2016 (2016-02-15)[2]) [±]
Preview release	Git [±]
Development status	Active
Written in	C and Assembly[3]
Operating system	Windows, OS X, and Linux; may be compiled for other OSes.[4]
Platform	x86, ARM, PowerPC, MIPS, DEC Alpha, Blackfin, AVR32, SH-4, and SPARC; may be compiled for other desktop computers
Type	Multimedia framework
License	LGPL 2.1+, GPL 2+ Unredistributable if compiled as such[5]
Website	ffmpeg.org

FFmpeg is a free software project that produces libraries and programs for handling multimedia data. FFmpeg includes libavcodec, an audio/video codec library used by several other projects, libavformat, an audio/video container mux and demux library, and the ffmpeg command line program for transcoding multimedia files. FFmpeg is published under the GNU Lesser General Public License 2.1+ or GNU General Public License 2+ (depending on which options are enabled).^[6]

FFmpeg is developed under Linux, but it can be compiled under most operating systems, including Mac OS X, Microsoft Windows, as well as AmigaOS and its heir MorphOS. Most computing platforms and microprocessor instruction set architectures are also supported, like x86 (IA-32 and x86-64), PPC (PowerPC), ARM, DEC Alpha, SPARC, and MIPS.^[7]

The name of the project is inspired by the MPEG video standards group, together with "FF" for "fast forward".^[8] The logo uses a zigzag pattern that shows how MPEG video codecs handle entropy encoding.^[9]

History

The project was started by Fabrice Bellard^[6] (using the pseudonym "Gérard Lantau") in 2000, and was led by Michael Niedermayer from 2004 until 2015.^[10] Many FFmpeg developers are also part of the MPlayer project.

FFmpeg version 0.5 appeared after a long time without formal releases. Meanwhile, the project approximately publishes a new release every three months to be used by "distributors and system integrators", but FFmpeg developers recommend that users compile the software from source using the latest build from their source code Git version control system.^[11]

Two video coding formats with corresponding codecs and one container format were invented in the FFmpeg project during its development. The two video codecs are the lossless FFV1, and the lossless and lossy Snow, the development of which has stalled, while its bit-stream format has not been finalized yet, making it experimental since 2011. The multimedia container format called NUT is no longer being actively developed, but still maintained.^[12]

In summer 2010, Fiona Glaser, Ronald Bultje, and David Conrad of the FFmpeg Team announced the ffvp8 decoder. Through testing, they determined that ffvp8 was faster than Google's own libvpx decoder.^[13][14] Starting with version 0.6, FFmpeg also supported WebM and VP8.^[15]

Since May 2011, an independent developer offers frequently updated ports of the FFmpeg tools for Windows platforms, to which the FFmpeg official website links.^[16]

In October 2013, a native VP9^[17] and the OpenHEVC decoder, an open source High Efficiency Video Coding (HEVC) decoder, were added to FFmpeg.^[18]

On January 10, 2014, two Google employees announced that over 1000 bugs had been fixed in FFmpeg during the previous two years by means of fuzz testing.^[19] FFmpeg 2.5, released in December 2014, supports an MPEG-DASH muxer.^[20]

On July 31, 2015, lead maintainer Michael Niedermeyer announced that he would be resigning, in order to help resolve the fork situation with Libav.^[10]

Libav Fork

On March 13, 2011, a group of FFmpeg developers decided to fork the project under the name "Libav".^[21][22][23] The event was related to a recent issue in project management, in which developers disagreed with the leadership of FFmpeg.^[24][25][26] The maintainer of FFmpeg packages for the Debian^[27] and Ubuntu^[28] Linux distributions, being one of the group of developers who forked FFmpeg, switched the distributions to Libav. In November 2013, Debian Developer Rogério Brito started to reincorporate FFmpeg into Debian and Ubuntu, with user support.^[29][30] On July 8, 2015, Debian ultimately switched back to FFmpeg, replacing Libav, citing security issues with the latter.^[31]

Components

The project comprises several components:

• ffmpeg is a command-line tool that converts audio or video formats. It can also grab and encode in real-time from various sources such as a TV card etc.
• ffserver is an HTTP and RTSP multimedia streaming server for live broadcasts. It can also time shift live broadcast.
• ffplay is a simple media player based on SDL and on the FFmpeg libraries.
• ffprobe is a command-line tool to show media information (text, CSV, XML, JSON), see also Mediainfo.
• libswresample is a library containing audio resampling routines.
• libavresample is a library containing audio resampling routines from the Libav project, similar to libswresample from ffmpeg.
• libavcodec is a library containing all the FFmpeg audio/video encoders and decoders. Most codecs were developed from scratch to ensure best performance and high code reusability.
• libavformat is a library containing demuxers and muxers for audio/video container formats.
• libavutil is a helper library containing routines common to different parts of FFmpeg. This library includes hash functions (Adler-32, CRC, MD5, RIPEMD, SHA-1. SHA-2, MurmurHash3, HMAC MD-5, HMAC SHA-1 and HMAC SHA-2), ciphers (DES, RC4, AES, AES-CTR, TEA, XTEA, Blowfish, CAST-128, Twofish and Camellia), LZO decompressor and Base64 encoder/decoder.
• libpostproc is a library containing video postprocessing routines.
• libswscale is a library containing video image scaling and colorspace/pixelformat conversion routines.
• libavfilter is the substitute for vhook which allows the video/audio to be modified or examined between the decoder and the encoder.

Supported Codecs, container formats, protocols and pixel formats

The PGMYUV image format is a homebrewn variant of the binary (P5) PGM Netpbm format. FFmpeg also supports 16-bit depths of the PGM and PPM formats, and the binary (P7) PAM format with or without alpha channel, depth 8 bit or 16 bit for pix_fmts monob, gray, gray16be, rgb24, rgb48be, ya8, rgba, rgb64be.

Codecs

In addition to FFV1 and Snow codecs, which were created and developed from within FFmpeg, the project also supports codecs from the following:

The default MPEG-4 codec used by FFmpeg for encoding has the FourCC of FMP4.

Container formats

• ASF
• AVI and also input from AviSynth
• BFI^[35]
• CAF
• FLV
• GXF, General eXchange Format, SMPTE 360M
• IFF^[36]
• ISO base media file format (including QuickTime, 3GP and MP4)
• Matroska (including WebM)
• Maxis XA^[37]
• MPEG program stream
• MPEG transport stream (including AVCHD)
• MXF, Material eXchange Format, SMPTE 377M
• MSN Webcam stream^[38]
• NUT^[12]
• Ogg
• OMA^[39]
• RL2^[40]
• TXD^[34]
• WTV

Protocols

Open standards

IETF FTP, TCP, UDP, UDP-Lite, Gopher, HTTP, RTP, RTSP, SDP

SFTP (via libssh)

HLS^[41]

Server Message Block (via libsmbclient)

MMS over TCP and MMS over HTTP

Icecast protocol

Proprietary

Adobe RTMP, RTMPT, RTMPE, RTMPTE and RTMPS

RealMedia RTSP/RDT

Pixel formats

FFmpeg supports many pixel formats.^[42] Some of these formats are only supported as input formats, the command ffmpeg -pix_fmts lists brief explanations. Example, as of 2015 the grayscale with alpha format ya16be (corresponding to NetPBM PAM GRAYSCALE_ALPHA in 32 bits) was not yet supported as output format.

1. ↑ RGBx (rgb0) and xBGR (0bgr)
2. ↑ used in YUV-centric codecs such like H.264
3. 1 2 3 4 YVU9, YV12, YV16, and YV24 are supported as rawvideo codec in FFmpeg.
4. ↑ 16bpc (P016) is not supported
5. ↑ aka YUY2 in Windows
6. ↑ 10bpc (Y210) and 16bpc (Y216) are not supported
7. ↑ 16bpc (P216) is not supported
8. ↑ 8bpc (AYUV) is not supported
9. ↑ used in JPEG2000

Note that FFmpeg still does not support IMC1-IMC4, AI44, CYMK, RGB Float, RGBE, Log RGB and such like.

Legal aspects

FFmpeg contains more than 100 codecs,^[43] most of which use compression techniques of one kind or another. Many such compression techniques may be subject to legal claims relating to software patents.^[44] Such claims may be enforceable in countries like the United States which have implemented software patents, but are considered unenforceable or void in countries that have not implemented software patents like in countries that are members of the European Union.

FFmtech Foundation

In June 2011 an election was organized to establish the board of FFmtech foundation,^[45] a non-profit organization dedicated for managing donation funds. It was designed to offer reimbursement for expenses and work done to FFmpeg and Libav. However, according to FFmpeg developer Ronald Bultje the results have been doubtful.^[46]

Projects using FFmpeg

FFmpeg is used by software such as VLC media player, xine, HandBrake, Plex, Blender, YouTube,^[47] and MPC-HC;^[48] it handles video and audio playback in Google Chrome,^[48] and Linux version of Firefox.^[49] Graphical user interface front-ends for FFmpeg have been developed, including Avanti,^[50] and XMedia Recode. JavaCV, a Java wrapper for OpenCV, includes a supplementary Java wrapper for FFmpeg.^[51]

FFmpeg is used by ffdshow, LAV Filters, GStreamer FFmpeg plug-in, Perian and OpenMAX IL to expand the encoding and decoding capabilities of their respective multimedia platform.

See also

• MEncoder, a similar project
• RetroCode, a similar project
• Open source codecs and containers

References

External links

• Official website
• FFmpeg at Open Hub