Newer investigations, such as Distant Viewing TV , also indicate a shift in the field toward projects concerned with using computational techniques to expand the scope of materials digital humanists can investigate. There are many valuable, free, and open-source tools and resources available to those interested in working with audiovisual materials for example, the Programming Historian tutorial Editing Audio with Audacity , and this tutorial will introduce another: FFmpeg.
In addition to being a software and web-developer tool, FFmpeg can be used at the command-line to perform many common, complex, and important tasks related to audiovisual file management, alteration, and analysis. These kinds of processes, such as editing, transcoding re-encoding , or extracting metadata from files, usually require access to other software such as a non-linear video editor like Adobe Premiere or Final Cut Pro , but FFmpeg allows a user to operate on audiovisual files directly without the use of third-party software or interfaces.
As such, knowledge of the framework empowers users to manipulate audiovisual materials to meet their needs with a free, open-source solution that carries much of the functionality of expensive audio and video editing software. This tutorial will provide an introduction to reading and writing FFmpeg commands and walk through a use-case for how the framework can be used in Digital Humanities scholarship specifically, how FFmpeg can be used to extract and analyze color data from an archival video source.
Additionally, a basic understanding of audiovisual codecs and containers will also be useful to understanding what FFmpeg does and how it works. We will provide some additional information and discuss codecs and containers in a bit more detail in the Preliminary Command Examples section of this tutorial.
Installing FFmpeg can be the most difficult part of using FFmpeg. Thankfully, there are some helpful guides and resources available for installing the framework based on your operating system.
The simplest option is to use a package manager such as Homebrew to install FFmpeg and ensure it remains in the most up-to-date version.
Homebrew is also useful in ensuring that your computer has the necessary dependencies installed to ensure FFMpeg runs properly. To complete this kind of installation, follow these steps:. After installing, it is best practice to update Homebrew and FFmpeg to ensure all dependencies and features are most up-to-date by running:. Windows users can use the package manager Chocolately to install and maintain FFmpeg.
Linuxbrew , a program similar to Homebrew, can be used to install and maintain FFmpeg in Linux. Reto Kromer also provides a helpful Linux installation guide that closely resembles the Mac OS installation. Your distribution of Linux may also have its own package manager already installed that include FFmpeg packages available.
If you see a long output of information, the installation was successful! It should look similar to this:. If you see something like -bash: ffmpeg: command not found then something has gone wrong. Next, we will look at some examples of several different commands that use this structure and syntax. For this tutorial, we will be taking an archival film called Destination Earth as our object of study.
This film has been made available by the Prelinger Archives collection on the Internet Archive. Released in , this film is a prime example of Cold War-era propaganda produced by the American Petroleum Institute and John Sutherland Productions that extols the virtues of capitalism and the American way of life. Utilizing the Technicolor process, this science-fiction animated short tells a story of a Martian society living under an oppressive government and their efforts to improve their industrial methods.
They send an emissary to Earth who discovers the key to this is oil refining and free-enterprise. We will be using this video to introduce some of the basic functionalities of FFmpeg and analyzing its color properties in relation to its propagandist rhetoric.
Take a few minutes to watch the video and get a sense of its structure, message, and visual motifs before moving on with the next commands. This will help illuminate how digital audiovisual files are constructed and provide a foundation for the rest of the tutorial. The output of a basic ffprobe command with destEarth. The Input 0 line of the reports identifies the container as ogg. Different containers other common ones include. Run another ffprobe command, this time with the.
In this use of the script, the output file will run at half the speed of the original. If you just wanted the audio from a video file, you can use this command to create an audio only file. Take an audio file, then cut the volume in half and output it to a new file.
Similar to the playback script, you're multiplying the original volume by a value to get the new value for the volume. You can change the video resolution for a video file with this script. Then you copy the audio codec because you aren't changing it, and output your changes to the new file output. These are just a few interesting commands you can do with ffmpeg! We hope they give you a sense of what's possible with the tool, and make you feel more confident about building and tweaking your own scripts.
Have fun! Responsive media: the right approach for images is not the right approach for video. The future of [ultra] low-latency video streaming. Top 7 causes of streaming video buffering issues. Handling video has never been easier. Search Ctrl K. Get started. FFmpeg - command-line interface that lets you work with your video, audio, or other media. FFplay - a media player. FFserver - a streaming media web server.
FFprobe - a stream analysis tool. Check out download options, documentation, their community, report bugs, read the source code, add to ffmpeg if you want, or hire someone to help you if it's all too much. FFmpeg Docs - This is linked off the website listed above, but if you want to go straight to a list of all the different options for scripts, go here. If you spend some time digging around here, you can find helpful information about how to set up scripts for various features you may be interested in.
Understanding Video Parameters: ffprobe - Review details about your videos and their performance with ffprobe. Erikka Innes Developer Evangelist. The resignation of Michael Niedermayer as leader of FFmpeg yesterday has come by surprise.
He has worked tirelessly on the FFmpeg project for many years and we must thank him for the work that he has done. We hope that in the future he will continue to contribute to the project.
In the coming weeks, the FFmpeg project will be managed by the active contributors. The last four years have not been easy for our multimedia community - both contributors and users. We should now look to the future, try to find solutions to these issues, and to have reconciliation between the forks, which have split the community for so long.
Unfortunately, much of the disagreement has taken place in inappropriate venues so far, which has made finding common ground and solutions difficult. We aim to discuss this in our communities online over the coming weeks, and in person at the VideoLAN Developer Days in Paris in September: a neutral venue for the entire open source multimedia community. After graciously hosting our projects FFmpeg , MPlayer and rtmpdump for 4 years, Arpi our hoster has informed us that we have to secure a new host somewhere else immediately.
If you want to host an open source project, please let us know, either on ffmpeg-devel mailing list or irc. We have made a new major release 2. It contains all features and bugfixes of the git master branch from the 6th March. Please see the Release Notes for a list of note-worthy changes. You can already get in contact with mentors and start working on qualification tasks. Registration at Google for students will open March 16th. The event will take place on 21st and 22nd of March.
We demonstrate usage of FFmpeg, answer your questions and listen to your problems and wishes. If you have media files that cannot be processed correctly with FFmpeg, be sure to have a sample with you so we can have a look! You can read the details here.
The workshop is targeted at FFmpeg beginners. First the basics of multimedia will be covered. Thereafter you will learn how to use that knowledge and the FFmpeg CLI tools to analyse and process media files. The workshop is in German language only and prior registration is necessary. The workshop will be on Saturday starting at 10 o'clock. We wanted you to know there are FFmpeg packages in Debian unstable again.
A big thank-you to Andreas Cadhalpun and all the people that made it possible. It has been anything but simple. Unfortunately that was already the easy part of this news. The bad news is the packages probably won't migrate to Debian testing to be in the upcoming release codenamed jessie. Read the argumentation over at Debian. However things will come out in the end, we hope for your continued remarkable support! We all know FFmpeg is used by the industry, but even while there are countless products building on our code, it is not at all common for companies to step up and help us out when needed.
So a big thank-you to Samsung and the OPW program committee! If you are thinking on participating in OPW as an intern, please take a look at our OPW wiki page for some initial guidelines. The page is still a work in progress, but there should be enough information there to get you started.
If you, on the other hand, are thinking on sponsoring work on FFmpeg through the OPW program, please get in touch with us at opw ffmpeg. With your help, we might be able to secure some extra intern spots for this round!
Please see the changelog for more details. Following our previous post regarding our participation on this year's OPW Outreach Program for Women , we are now reaching out to our users both individuals and companies to help us gather the needed money to secure our spot in the program.
We need to put together 6K USD as a minimum but securing more funds would help us towards getting more than one intern. If you would like to donate by money transfer or by check, please get in touch by e-mail and we will get back to you with instructions. The FFmpeg project is proud to announce a brand new version of the website made by db0.
While this was initially motivated by the need for a larger menu, the whole website ended up being redesigned, and most pages got reworked to ease navigation.
We hope you'll enjoy browsing it. FFmpeg has started the process to become an OPW includer organization for the next round of the program, with internships starting December 9. The OPW aims to "Help women cis and trans and genderqueer to get involved in free and open source software". Part of the process requires securing funds to support at least one internship 6K USD , so if you were holding on your donation to FFmpeg, this is a great chance for you to come forward, get in touch and help both the project and a great initiative!
We have set up an email address you can use to contact us about donations and general inquires regarding our participation in the program. Hope to hear from you soon! They fix a security issue in the LZO implementation , as well as several other bugs. See the git log for details. The event will take place from 8th to 10th of May. In particular, codec options are applied by ffmpeg after the stream selection process and thus do not influence the latter.
If no -codec option is specified for a stream type, ffmpeg will select the default encoder registered by the output file muxer. An exception exists for subtitles.
If a subtitle encoder is specified for an output file, the first subtitle stream found of any type, text or image, will be included.
This applies generally as well: when the user sets an encoder manually, the stream selection process cannot check if the encoded stream can be muxed into the output file. If it cannot, ffmpeg will abort and all output files will fail to be processed. There are three output files specified, and for the first two, no -map options are set, so ffmpeg will select streams for these two files automatically.
For video, it will select stream 0 from B. For audio, it will select stream 3 from B. For subtitles, it will select stream 2 from B. For out3.
The -map 1:a option will select all audio streams from the second input B. No other streams will be included in this output file. For the first two outputs, all included streams will be transcoded. The encoders chosen will be the default ones registered by each output format, which may not match the codec of the selected input streams. For the third output, codec option for audio streams has been set to copy , so no decoding-filtering-encoding operations will occur, or can occur.
Packets of selected streams shall be conveyed from the input file and muxed within the output file. Although out1. The subtitle stream of C. However, in out2. The presence of -an disables audio stream selection for out2. The overlay filter requires exactly two video inputs, but none are specified, so the first two available video streams are used, those of A. The output pad of the filter has no label and so is sent to the first output file out1. Due to this, automatic selection of the video stream is skipped, which would have selected the stream in B.
The audio stream with most channels viz. The 2nd output file, out2. So, even though the first subtitle stream available belongs to C. The selected stream, stream 2 in B.
The above command will fail, as the output pad labelled [outv] has been mapped twice. None of the output files shall be processed. The video stream from B. Then a copy each is mapped to the first and third output files. The overlay filter, requiring two video inputs, uses the first two unused video streams. Those are the streams from A. The aresample filter is sent the first unused audio stream, that of A.
Since this filter output is also unlabelled, it too is mapped to the first output file. The presence of -an only suppresses automatic or manual stream selection of audio streams, not outputs sent from filtergraphs. Both these mapped streams shall be ordered before the mapped stream in out1.
The video, audio and subtitle streams mapped to out2. Options which do not take arguments are boolean options, and set the corresponding value to true. They can be set to false by prefixing the option name with "no".
For example using "-nofoo" will set the boolean option with name "foo" to false. Some options are applied per-stream, e. Stream specifiers are used to precisely specify which stream s a given option belongs to.
A stream specifier is a string generally appended to the option name and separated from it by a colon. Therefore, it would select the ac3 codec for the second audio stream. A stream specifier can match several streams, so that the option is applied to all of them. An empty stream specifier matches all streams. For example, -codec copy or -codec: copy would copy all the streams without reencoding. Matches the stream with this index. Stream numbering is based on the order of the streams as detected by libavformat except when a program ID is also specified.
In this case it is based on the ordering of the streams in the program. Otherwise, it matches all streams of the specified type.
Matches streams with the metadata tag key having the specified value. If value is not given, matches streams that contain the given tag with any value. Matches streams with usable configuration, the codec must be defined and the essential information such as video dimension or audio sample rate must be present.
Show help. An optional parameter may be specified to print help about a specific item. If no argument is specified, only basic non advanced tool options are shown. Print complete list of options, including shared and private options for encoders, decoders, demuxers, muxers, filters, etc.
Use the -decoders option to get a list of all decoders. Use the -encoders option to get a list of all encoders. Use the -formats option to get a list of all demuxers and muxers. Use the -formats option to get a list of all muxers and demuxers.
Use the -filters option to get a list of all filters. Use the -bsfs option to get a list of all bitstream filters. Use the -protocols option to get a list of all protocols.
Show autodetected sources of the input device. Some devices may provide system-dependent source names that cannot be autodetected. The returned list cannot be assumed to be always complete. Show autodetected sinks of the output device. Some devices may provide system-dependent sink names that cannot be autodetected. Indicates that repeated log output should not be compressed to the first line and the "Last message repeated n times" line will be omitted. Indicates that log output should add a [level] prefix to each message line.
This can be used as an alternative to log coloring, e. Only show fatal errors which could lead the process to crash, such as an assertion failure. This is not currently used for anything. Show all warnings and errors. Any message related to possibly incorrect or unexpected events will be shown.
Show informative messages during processing. This is in addition to warnings and errors. This is the default value. For example to enable repeated log output, add the level prefix, and set loglevel to verbose :. Another example that enables repeated log output without affecting current state of level prefix flag or loglevel :. By default the program logs to stderr. If coloring is supported by the terminal, colors are used to mark errors and warnings.
This file can be useful for bug reports. It also implies -loglevel debug. For example, to output a report to a file named ffreport. All FFmpeg tools will normally show a copyright notice, build options and library versions.
This option can be used to suppress printing this information. Allows setting and clearing cpu flags. This option is intended for testing. Override detection of CPU count. Exercise extreme caution when using this option. These options are provided directly by the libavformat, libavdevice and libavcodec libraries. To see the list of available AVOptions, use the -help option. They are separated into two categories:. These options can be set for any container, codec or device.
These options are specific to the given container, device or codec. For example to write an ID3v2. In the above example, a multichannel audio stream is mapped twice for output. The first instance is encoded with codec ac3 and bitrate k. The second instance is downmixed to 2 channels and encoded with codec aac.
A bitrate of k is specified for it using absolute index of the output stream. Force input or output file format. The format is normally auto detected for input files and guessed from the file extension for output files, so this option is not needed in most cases. Set number of times input stream shall be looped. Loop 0 means no loop, loop -1 means infinite loop. Allow forcing a decoder of a different media type than the one detected or designated by the demuxer.
Useful for decoding media data muxed as data streams.
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