FFplay

FFmpeg

FFmpeg

Multimedia framework

FFmpeg is a free and open-source software project consisting of a suite of libraries and programs for handling video, audio, and other multimedia files and streams. At its core is the command-line ffmpeg tool itself, designed for processing of video and audio files. It is widely used for format transcoding, basic editing (trimming and concatenation), video scaling, video post-production effects and standards compliance (SMPTE, ITU).

Quick Facts Original author(s), Developer(s) ...

FFmpeg also includes other tools: ffplay, a simple media player and ffprobe, a command-line tool to display media information. Among included libraries are libavcodec, an audio/video codec library used by many commercial and free software products, libavformat (Lavf),[8] an audio/video container mux and demux library, and libavfilter, a library for enhancing and editing filters through a Gstreamer-like filtergraph.[9]

FFmpeg is part of the workflow of many other software projects, and its libraries are a core part of software media players such as VLC, and has been included in core processing for YouTube and Bilibili.[10] Encoders and decoders for many audio and video file formats are included, making it highly useful for the transcoding of common and uncommon media files.

FFmpeg is published under the LGPL-2.1-or-later or GPL-2.0-or-later, depending on which options are enabled.[11]

History

The project was started by Fabrice Bellard[11] (using the pseudonym "Gérard Lantau") in 2000, and was led by Michael Niedermayer from 2004 until 2015.[12] Some FFmpeg developers were also part of the MPlayer project.

The name of the project is inspired by the MPEG video standards group, together with "FF" for "fast forward", so FFmpeg stands for "Fast Forward Moving Picture Experts Group".[13] The logo represents a zigzag scan pattern that shows how MPEG video codecs handle entropy encoding.[14]

On March 13, 2011, a group of FFmpeg developers decided to fork the project under the name Libav.[15][16][17] The event was related to an issue in project management, in which developers disagreed with the leadership of FFmpeg.[18][19][20]

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.[21]

In January 2018, the ffserver command-line program – a long-time component of FFmpeg – was removed.[22] The developers had previously deprecated the program citing high maintenance efforts due to its use of internal application programming interfaces.[23]

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.[24]

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.[25]

In summer 2010, FFmpeg developers Fiona Glaser, Ronald Bultje, and David Conrad, announced the ffvp8 decoder. Through testing, they determined that ffvp8 was faster than Google's own libvpx decoder.[26][27] Starting with version 0.6, FFmpeg also supported WebM and VP8.[28]

In October 2013, a native VP9[29] decoder and OpenHEVC, an open source High Efficiency Video Coding (HEVC) decoder, were added to FFmpeg.[30] 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.[31] Since version 3.4 "Cantor" FFmpeg supported the FITS image format.[32] Since November 2018 in version 4.1 "al-Khwarizmi" AV1 can be muxed in MP4 and Matroska incl. WebM.[33][34]

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[35] 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)[8] 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, ciphers, LZO decompressor and Base64 encoder/decoder.
  • libpostproc is a library containing older H.263 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 (for debugging) between the decoder and the encoder. Filters have been ported from many projects including MPlayer and avisynth.
  • libavdevice is a library containing audio/video io through internal and external devices.

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.[36]

Special purpose hardware

There are a variety of application-specific integrated circuits (ASICs) for audio/video compression and decompression. These ASICs can partially or completely offload the computation from the host CPU. Instead of a complete implementation of an algorithm, only the API is required to use such an ASIC.[37]

More information Firm, ASIC ...

The following APIs are also supported: DirectX Video Acceleration (DXVA2, Windows), Direct3D 11 (D3D11VA, Windows), Media Foundation (Windows), VideoToolbox (macOS), RockChip MPP, OpenCL, OpenMAX, MMAL (Raspberry Pi), MediaCodec (Android OS), V4L2 (Linux). Depending on the environment, these APIs may lead to specific ASICs, to GPGPU routines, or to SIMD CPU code.[41]

Supported codecs and formats

Image formats

FFmpeg supports many common and some uncommon image formats.

The PGMYUV image format is a homebrew 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

Further information: libavcodec

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

More information Group, Format type ...

Muxers

Output formats (container formats and other ways of creating output streams) in FFmpeg are called "muxers". FFmpeg supports, among others, the following:

Pixel formats

More information Type, Color ...
  1. [p 1]
    10-bit color components with 2-bit padding (X2RGB10)
  2. [p 2]
    RGBx (rgb0) and xBGR (0bgr) are also supported
  3. [p 3]
    used in YUV-centric codecs such like H.264
  4. [p 4]
    YVU9, YV12, YV16, and YV24 are supported as rawvideo codec in FFmpeg.
  5. [p 5]
    I420 a.k.a. YUV420P
  6. [p 6]
    aka YUY2 in Windows
  7. [p 7]
    UYVY 10bpc without a padding is supported as bitpacked codec in FFmpeg. UYVY 10bpc with 2-bits padding is supported as v210 codec in FFmpeg. 16bpc (Y216) is supported as targa_y216 codec in FFmpeg.
  8. [p 8]
    I422 a.k.a. YUV422P
  9. [p 9]
    XV30 a.k.a. XVYU2101010
  10. [P 10]
    XV36
  11. [P 11]
    VUYA a.k.a. AYUV
  12. [P 12]
    10bpc (Y410), 12bpc (Y412), and Y416 (16bpc) are not supported.
  13. [P 13]
    I444 a.k.a. YUV444P
  14. [P 14]
    used in JPEG2000

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

De facto standards

Supported filters

FFmpeg supports, among others, the following filters.[68]

Audio

Video

  • Transformations
    • Cropping (crop, cropdetect)
    • Fading (fade)
    • Scaling (scale)
    • Padding (pad)
    • Rotation (rotate)
    • Transposition (transpose)
    • Others:
      • Lens correction (lenscorrection)
      • OpenCV filtering (ocv)
      • Perspective correction (perspective)
  • Temporal editing
    • Framerate (fps, framerate)
    • Looping (loop)
    • Trimming (trim)
  • Deinterlacing (bwdif, idet, kerndeint, nnedi, yadif, w3fdif)
  • Inverse Telecine
  • Filtering
  • Denoising (atadenoise, bitplanenoise, dctdnoiz, owdenoise, removegrain)
  • Logo removal (delogo, removelogo)
  • Subtitles (ASS, subtitles)
  • Alpha channel editing (alphaextract, alphamerge)
  • Keying (chromakey, colorkey, lumakey)
  • Frame detection
    • Black frame detection (blackdetect, blackframe)
    • Thumbnail selection (thumbnail)
  • Frame Blending (blend, tblend, overlay)
  • Video stabilization (vidstabdetect, vidstabtransform)
  • Color and Level adjustments
    • Balance and levels (colorbalance, colorlevels)
    • Channel mixing (colorchannelmixer)
    • Color space (colorspace)
    • Parametric adjustments (curves, eq)
  • Histograms and visualization
  • Drawing
  • OCR
  • Quality measures
  • Lookup Tables
    • lut, lutrgb, lutyuv, lut2, lut3d, haldclut

Supported test patterns

  • SMPTE color bars (smptebars and smptehdbars)
  • EBU color bars (pal75bars and pal100bars)

Supported LUT formats

Supported media and interfaces

FFmpeg supports the following devices via external libraries.[70]

Media

Physical interfaces

  • IEEE 1394 (a.k.a. FireWire; via libdc1394 and libraw1394; input only)
  • IEC 61883 (via libiec61883; input only)
  • DeckLink
  • Brooktree video capture chip (via bktr driver; input only)

Audio IO

Video IO

Screen capture and output

Others

Applications

FFmpeg contains more than 100 codecs,[71] 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.[72] 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.[73][original research] Patents for many older codecs, including AC3 and all MPEG-1 and MPEG-2 codecs, have expired.[citation needed]

FFmpeg is licensed under the LGPL license, but if a particular build of FFmpeg is linked against any GPL libraries (notably x264), then the entire binary is licensed under the GPL.

Projects using FFmpeg

Main category: Software that uses FFmpeg

FFmpeg is used by software such as Blender, Cinelerra-GG Infinity, HandBrake, Kodi, MPC-HC, Plex, Shotcut, VirtualDub2 (a VirtualDub fork),[74] VLC media player, xine and YouTube.[75][76] It handles video and audio playback in Google Chrome[76] and the Linux version of Firefox.[77] GUI front-ends for FFmpeg have been developed, including Multimedia Xpert[78] and XMedia Recode.

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

As part of NASA's Mars 2020 mission, FFmpeg is used by the Perseverance rover on Mars for image and video compression before footage is sent to Earth.[79]

See also

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