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 (Lavf), 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).
The name of the project is inspired by the MPEG video standards group, together with "FF" for "fast forward". The logo uses a zigzag pattern that shows how MPEG video codecs handle entropy encoding.
Video FFmpeg
History
The project was started by Fabrice Bellard (using the pseudonym "Gérard Lantau") in 2000, and was led by Michael Niedermayer from 2004 until 2015. Some FFmpeg developers were also part of the MPlayer project.
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.
In January 2018, the ffserver command-line program - a long-time component of FFmpeg - was removed. The developers had previously deprecated the program citing high maintenance efforts due to its use of internal APIs.
The project publishes a new release every three months on average. While release versions are available from the website for download, FFmpeg developers recommend that users compile the software from source using the latest build from their source code Git version control system.
Codec history
Two video coding formats with corresponding codecs and one container format have been created within the FFmpeg project so far. The two video codecs are the lossless FFV1, and the lossless and lossy Snow codec. Development of Snow 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.
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. Starting with version 0.6, FFmpeg also supported WebM and VP8.
In October 2013, a native VP9 and the OpenHEVC decoder, an open source High Efficiency Video Coding (HEVC) decoder, were added to FFmpeg. In 2016 the native AAC encoder was considered stable, removing support for the two external AAC encoders from VisualOn and FAAC. FFmpeg 3.0 (nicknamed "Einstein" ) retained build support for the Fraunhofer FDK AAC encoder.
Maps FFmpeg
Components
Command line tools
- ffmpeg is a command-line tool that converts audio or video formats. It can also capture and encode in real-time from various hardware and software sources such as a TV capture card.
- ffplay is a simple media player utilizing SDL and the FFmpeg libraries.
- ffprobe is a command-line tool to display media information (text, CSV, XML, JSON), see also Mediainfo.
Libraries
- 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 of the native FFmpeg audio/video encoders and decoders. Most codecs were developed from scratch to ensure best performance and high code reusability.
- libavformat (Lavf) 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 older h263 based 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. Filters have been ported from many projects including MPlayer and avisynth
Supported hardware
CPUs
FFmpeg encompasses software implementations of video and audio compressing and decompressing algorithms. These can be compiled and run on diverse instruction sets.
Many widespread instruction sets are supported by FFmpeg, including x86 (IA-32 and x86-64), PPC (PowerPC), ARM, DEC Alpha, SPARC, and MIPS.
Special purpose hardware
Various application-specific integrated circuit related to video and audio compression and decompression do exist. Such ASIC can perform the computation for audio/video decompression or compression partly or fully to offload these from the host CPU. To make use of such ASIC, instead of a complete implementation of some algorithm, only the API is required. There are numerous ASICs and APIs available, of which several are supported by FFmpeg.
Use with the FFmpeg Utility
Internal hardware acceleration decoding is enabled through -hwaccel option. It starts decoding normally, but if a decodable stream is detected in hardware then the decoder designates all significant processing to that hardware, thus accelerate the decoding process up to the hilt. Whereas if there is no decodable streams (it happens on an unsupported codec or profile), hardware acceleration will be skipped and it still be decoded in software automatically. -hwaccel_device option is applied when the hardware requires a particular device to function especially there are several graphic cards are available.
Supported codecs and formats
Image formats
FFmpeg supports many common and some uncommon image 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.
Supported formats
In addition to FFV1 and Snow formats, which were created and developed from within FFmpeg, the project also supports the following formats:
Muxers
Output formats (container formats and other ways of creating output streams) in FFmpeg are called "muxers". FFmpeg supports, among others, the following:
- AIFF
- ASF
- AVI and also input from AviSynth
- BFI
- CAF
- FLV
- GIF
- GXF, General eXchange Format, SMPTE 360M
- HLS, HTTP Live Streaming
- IFF
- ISO base media file format (including QuickTime, 3GP and MP4)
- Matroska (including WebM)
- Maxis XA
- MPEG-DASH
- MPEG program stream
- MPEG transport stream (including AVCHD)
- MXF, Material eXchange Format, SMPTE 377M
- MSN Webcam stream
- NUT
- Ogg
- OMA
- RL2
- Segment, for creating segmented video streams
- Smooth Streaming
- TXD
- WTV
Pixel formats
FFmpeg supports many pixel formats. Some of these formats are only supported as input formats. The command ffmpeg -pix_fmts provides a list of supported pixel formats.
FFmpeg does not support IMC1-IMC4, AI44, CYMK, RGBE, Log RGB and other formats. It also does not yet support ARGB 1:5:5:5, 2:10:10:10, or other BMP bitfield formats that are not commonly used.
Supported protocols
Open standards
- IETF RFCs
- FTP
- Gopher
- HTTP
- HTTPS
- RTP
- RTSP
- SCTP
- SDP
- SRTP
- TCP
- TLS
- UDP
- UDP-Lite
- IETF I-Ds:
- HLS
- SFTP (via libssh)
- Microsoft OSP
- CIFS/SMB (via libsmbclient)
- MMS over TCP (MS-MMSP) and MMS over HTTP (MS-WMSP)
- Pro-MPEG Forum: Pro-MPEG CoP #3 r2
De facto standards
- RTSPS (RTSP over TLS)
Open-source
- Icecast protocol
Proprietary
- Adobe RTMP, RTMPT, RTMPE, RTMPTE and RTMPS (can be compiled with the native support or using rtmpdumps librtmp library)
- RealMedia RTSP/RDT
Supported filters
FFmpeg supports, among others, the following filters.
Audio
Video
Legal aspects
FFmpeg contains more than 100 codecs, 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. Such claims may be enforceable in countries like the United States which have implemented software patents, but are considered unenforceable or void in member countries of the European Union, for example.
FFmtech Foundation
In June 2011 an election was organized to establish the board of FFmtech foundation, 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.
Projects using FFmpeg
FFmpeg is used by software such as VLC media player, xine, Plex, Kodi, Blender, YouTube, and MPC-HC; it handles video and audio playback in Google Chrome, and Linux version of Firefox. Graphical user interface front-ends for FFmpeg have been developed, including Avanti, XMedia Recode and Multimedia Xpert. JavaCV, a Java wrapper for OpenCV, includes a supplementary Java wrapper for FFmpeg.
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.
Forks
Libav
On March 13, 2011, a group of FFmpeg developers decided to fork the project under the name "Libav". The event was related to an issue in project management, in which developers disagreed with the leadership of FFmpeg.
See also
- MEncoder, a similar project
- List of open-source codecs
References
External links
- Official website
- FFmpeg at Open Hub
Source of the article : Wikipedia
0 Comments