Using -shortest cuts the video file short if the audio file is shorter than the video. So is there a flag to tell ffmpeg to cut the keep the length of the output video to the length of the input video? Your command would be:. This assumes the audio you want is in the first stream of audiofile.
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Inspired by deadcode's answer, I need to make clear, that "no flag to automate" is of course not true, if you are willing to reencode : In this case go with apad as suggested by deadcode. This will synthesize the apad filter without a filter graph, thus allowing a mux without reencoding. Sign up to join this community. The best answers are voted up and rise to the top. Home Questions Tags Users Unanswered. Asked 5 years, 7 months ago. Active 1 year, 10 months ago.
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I'm adding audio to a video file using ffmpeg like so ffmpeg -i videofile. Please select a correct answer. The only real correct one is the one by Zurechtweiser.
I've created a tool to create a grid of movies, like in the Brady Bunch opening. It's a cool, funny effect. Here's a sample movie showing the grid. The problem is that ffmpeg is choosing the shortest movie to determine the maximum length of overlaid videos, but still using the full length of the first audio track to determine the overall output movie length.
So all my videos stop moving when the shortest one ends, but the audio plays on for full length of the first movie. How can I either 1 set the length of the output movie to the longest input movie or 2 match the audio length to the shortest movie length as well?
Gist of my script. Based on this ffmpeg example usage which exhibits the same audio problem:. By default the shortest input for the overlay will simply stop and the last frame will be repeated while the longer input continues.
See overlay filter docs. Add the -shortest output option. This is a different option that the overlay shortest option; place it outside the filtergraph as an output option before the output file. Now the final output file will be the same duration as the shortest stream: either the video from the filtergraph, or the audio from one of your inputs which one exactly depends on the default stream selection behavior because I don't see you doing anything with the audio in the command.
IIRC, there may be an existing bug involving filtering and -shortest not doing what is expected, but I can't recall the details at the moment and am too lazy to look.
Just something to be aware of.
Learn more. Asked 4 years, 5 months ago. Active 4 years, 5 months ago. Viewed 3k times. Based on this ffmpeg example usage which exhibits the same audio problem: ffmpeg -i 1. Stan James. Stan James Stan James 1, 20 20 silver badges 33 33 bronze badges. As for " 1 " what do you want to happen to the shorter videos when they end but the longer continues?
Show last frame, just vanish?In libavfilter, a filter can have multiple inputs and multiple outputs. To illustrate the sorts of things that are possible, we consider the following filtergraph. This filtergraph splits the input stream in two streams, then sends one stream through the crop filter and the vflip filter, before merging it back with the other stream by overlaying it on top.
You can use the following command to achieve this:. The result will be that the top half of the video is mirrored onto the bottom half of the output video. Filters in the same linear chain are separated by commas, and distinct linear chains of filters are separated by semicolons. In our example, crop,vflip are in one linear chain, split and overlay are separately in another. The points where the linear chains join are labelled by names enclosed in square brackets.
In the example, the split filter generates two outputs that are associated to the labels [main] and [tmp]. The stream sent to the second output of splitlabelled as [tmp]is processed through the crop filter, which crops away the lower half part of the video, and then vertically flipped. The overlay filter takes in input the first unchanged output of the split filter which was labelled as [main]and overlay on its lower half the output generated by the crop,vflip filterchain.
Some filters take in input a list of parameters: they are specified after the filter name and an equal sign, and are separated from each other by a colon. The graph2dot program included in the FFmpeg tools directory can be used to parse a filtergraph description and issue a corresponding textual representation in the dot language.
You can then pass the dot description to the dot program from the graphviz suite of programs and obtain a graphical representation of the filtergraph. Note that this string must be a complete self-contained graph, with its inputs and outputs explicitly defined. For example if your command line is of the form:.
A filtergraph is a directed graph of connected filters. It can contain cycles, and there can be multiple links between a pair of filters. Each link has one input pad on one side connecting it to one filter from which it takes its input, and one output pad on the other side connecting it to one filter accepting its output.
Each filter in a filtergraph is an instance of a filter class registered in the application, which defines the features and the number of input and output pads of the filter. A filter with no input pads is called a "source", and a filter with no output pads is called a "sink". A filterchain consists of a sequence of connected filters, each one connected to the previous one in the sequence. A filterchain is represented by a list of ","-separated filter descriptions.
A filtergraph consists of a sequence of filterchains. A sequence of filterchains is represented by a list of ";"-separated filterchain descriptions. It may have one of two forms:. If the option value itself is a list of items e.FFMPEG Advanced Techniques Pt1 - Advanced Filters
The name and arguments of the filter are optionally preceded and followed by a list of link labels. A link label allows one to name a link and associate it to a filter output or input pad. When two link labels with the same name are found in the filtergraph, a link between the corresponding input and output pad is created. If an output pad is not labelled, it is linked by default to the first unlabelled input pad of the next filter in the filterchain.
For example in the filterchain. The first output pad of split is labelled "L1", the first input pad of overlay is labelled "L2", and the second output pad of split is linked to the second input pad of overlay, which are both unlabelled.It can also convert between arbitrary sample rates and resize video on the fly with a high quality polyphase filter.
Anything found on the command line which cannot be interpreted as an option is considered to be an output url. Selecting which streams from which inputs will go into which output is either done automatically or with the -map option see the Stream selection chapter. To refer to input files in options, you must use their indices 0-based. Similarly, streams within a file are referred to by their indices. Also see the Stream specifiers chapter. As a general rule, options are applied to the next specified file.
Therefore, order is important, and you can have the same option on the command line multiple times.
Each occurrence is then applied to the next input or output file. Exceptions from this rule are the global options e. Do not mix input and output files — first specify all input files, then all output files. Also do not mix options which belong to different files. All options apply ONLY to the next input or output file and are reset between files. The transcoding process in ffmpeg for each output can be described by the following diagram:. When there are multiple input files, ffmpeg tries to keep them synchronized by tracking lowest timestamp on any active input stream.
Encoded packets are then passed to the decoder unless streamcopy is selected for the stream, see further for a description. After filtering, the frames are passed to the encoder, which encodes them and outputs encoded packets. Finally those are passed to the muxer, which writes the encoded packets to the output file. Before encoding, ffmpeg can process raw audio and video frames using filters from the libavfilter library.
Several chained filters form a filter graph.FFmpeg only provides source code. Below are some links that provide it already compiled and ready to go. You can retrieve the source code through Git by using the command:. FFmpeg has always been a very experimental and developer-driven project.
It is a key component in many multimedia projects and has new features added constantly. Since FFmpeg is developed with Gitmultiple repositories from developers and groups of developers are available.
Approximately every 6 months the FFmpeg project makes a new major release. Between major releases point releases will appear that add important bug fixes but no new features. Note that these releases are intended for distributors and system integrators. Users that wish to compile from source themselves are strongly encouraged to consider using the development branch see abovethis is the only version on which FFmpeg developers actively work.
The release branches only cherry pick selected changes from the development branch, which therefore receives much more and much faster bug fixes such as additional features and security patches. It is the latest stable FFmpeg release from the 4. It is the latest stable FFmpeg release from the 3. It is the latest stable FFmpeg release from the 2. Amongst lots of other changes, it includes all changes from ffmpeg-mt, libav master oflibav 11 as of Hosting provided by telepoint.
Get the Sources Download Snapshot. Git Repositories. Browse Snapshot. Download xz tarball PGP signature. Download bzip2 tarball PGP signature. Download gzip tarball PGP signature. Changelog Release Notes. Get old releases.Because YouTube, Vimeo, and other similar sites will re-encode anything you give it the best practice is to provide the highest quality video that is practical for you to upload. Uploading the original content is the first recommendation, but this is not always a choice due to the file size or format, so re-encoding may be required.
This guide will show you how to create a high quality video using ffmpeg. First read the H. The examples below use the same method as shown in the encoding guide but optimized for YouTube. Re-encode the video and stream copy the audio. The output should be a similar quality as the input and will hopefully be a more manageable size. Same as above, but also re-encode the audio using AAC instead of stream copying it:.
You can do this with the following option:. You can see if your music file contains the album cover with ffmpeg. Look for a video stream:. If your music file does not contain album art then see the Create a video with a still image example above. You can use filters to create effects and to add text. This example will use the avectorscopeshowspectrumand showwaves filters to create effects, the overlay filter to place each effect, and the drawtext filter to add text:.
Use a faster -preset value, but note that this will increase the file size when using CRF mode. See the H. YouTube works however. Download all attachments as:. Powered by Trac 1. Last modified 22 months ago Last modified on Jun 13,PM. Attachments 2 musicfilter. Effects for audio album. Download in other formats: Plain Text.Note that this filter is not FDA approved, nor are we medical professionals. Nor has this filter been tested with anyone who has photosensitive epilepsy. FFmpeg and its photosensitivity filter are not making any medical claims.
That said, this is a new video filter that may help photosensitive people watch tv, play video games or even be used with a VR headset to block out epiletic triggers such as filtered sunlight when they are outside. Or you could use it against those annoying white flashes on your tv screen.
The filter fails on some input, such as the Incredibles 2 Screen Slaver scene. It is not perfect. If you have other clips that you want this filter to work better on, please report them to us on our trac. See for yourself. We are not professionals.
Please use this in your medical studies to advance epilepsy research. If you decide to use this in a medical setting, or make a hardware hdmi input output realtime tv filter, or find another use for this, please let me know. This filter was a feature request of mine since FFmpeg 4. Some of the highlights:.
We strongly recommend users, distributors, and system integrators to upgrade unless they use current git master. FFmpeg 3. This has been a long time coming but we wanted to give a proper closure to our participation in this run of the program and it takes time.
Sometimes it's just to get the final report for each project trimmed down, others, is finalizing whatever was still in progress when the program finished: final patches need to be merged, TODO lists stabilized, future plans agreed; you name it.
Without further ado, here's the silver-lining for each one of the projects we sought to complete during this Summer of Code season:. Stanislav Dolganov designed and implemented experimental support for motion estimation and compensation in the lossless FFV1 codec. The design and implementation is based on the snow video codec, which uses OBMC. Stanislav's work proved that significant compression gains can be achieved with inter frame compression.
Petru Rares Sincraian added several self-tests to FFmpeg and successfully went through the in-some-cases tedious process of fine tuning tests parameters to avoid known and hard to avoid problems, like checksum mismatches due to rounding errors on the myriad of platforms we support. His work has improved the code coverage of our self tests considerably. He also implemented a missing feature for the ALS decoder that enables floating-point sample decoding.
How to Encode Videos for YouTube, Facebook, Vimeo, twitch, and other Video Sharing Sites
We welcome him to keep maintaining his improvements and hope for great contributions to come. He succeeded in his task, and the FIFO muxer is now part of the main repository, alongside several other improvements he made in the process. Jai Luthra's objective was to update the out-of-tree and pretty much abandoned MLP Meridian Lossless Packing encoder for libavcodec and improve it to enable encoding to the TrueHD format.
For the qualification period the encoder was updated such that it was usable and throughout the summer, successfully improved adding support for multi-channel audio and TrueHD encoding. Jai's code has been merged into the main repository now. While a few problems remain with respect to LFE channel and 32 bit sample handling, these are in the process of being fixed such that effort can be finally put in improving the encoder's speed and efficiency.
Davinder Singh investigated existing motion estimation and interpolation approaches from the available literature and previous work by our own: Michael Niedermayer, and implemented filters based on this research.
These filters allow motion interpolating frame rate conversion to be applied to a video, for example, to create a slow motion effect or change the frame rate while smoothly interpolating the video along the motion vectors.