For example, to set the audio stream to be Vorbis, you would use the following command: ffmpeg -i input.mp3 -c:a libvorbis output.ogg This flag lets you set the different codec to use for each stream. So what do you do when you want to use a container like Matroska (which can handle almost any stream) but still influence which codecs are in the output? FFmpeg to the rescue! You can select the codecs needed by using the -c flag. May result in a file with the same codecs as input.mp4 had, which may or may not be what you want. This means the command: ffmpeg -i input.mp4 output.mkv For instance, containers like Matroska are designed to handle almost any stream you care to put in them, whether they're valid or not. This also works with videos: ffmpeg -i input.mp4 output.webmīecause WebM is a well-defined format, FFmpeg automatically knows what video and audio it can support and will convert the streams to be a valid WebM file.ĭepending on your container of choice, this won't always work. You didn't have to specify stream or container types, because FFmpeg figured it out for you. From FFmpeg's point of view, this means converting the MP3 audio stream into a Vorbis audio stream and wrapping this stream into an OGG container. This command takes an MP3 file called input.mp3 and converts it into an OGG file called output.ogg. Usually it automatically selects the correct codecs and container without any complex configuration.įor example, say you have an MP3 file and want it converted into an OGG file: ffmpeg -i input.mp3 output.ogg Luckily, FFmpeg is pretty clever with its default settings. The thing that trips up most people when it comes to converting audio and video is selecting the correct formats and containers. You should be prepared to settle in for a while when you use FFmpeg. To learn more, click on the links above.īe aware that video and audio encoding can take a very long time to run. This explanation is enough to get you through this article. Many require certain streams and metadata or put restrictions on the codecs or contents allowed. This is an abstract representation of media files and skips over a lot of the differences between containers. It all depends on what the container is set to allow. Different containers will allow for different streams, e.g., subtitles, chapter information, or other metadata. The streams in a container don't have to be just audio or video though. Some containers are highly advanced and allow for any sort of stream, including multiple video and audio streams inside a single container. It presents a single interface that media players and tools can interact with. The container is the wrapper for the streams. Neither is inherently better than the other, as each is trying to do different things. This means a FLAC-formatted file will be much larger than a Vorbis audio stream but should sound better. For example, the FLAC codec is good for high-quality lossless audio, whereas Vorbis is designed to compete with MP3 in file size while offering better audio quality. Each codec has its own properties, strengths, and weaknesses. The streams include the actual AV components, such as a movie's audio or video, and are encoded using a particular media encoding, or codec. Media filesĪt a very high-level view, a media file is broken up into a container and its streams.
Before we look at using FFmpeg, first we need to take a quick look at what a media file exactly is. In this article, we are interested in using it to convert files, so we won't be taking a deep dive into its entire feature set. It can be downloaded from the FFmpeg website or through most package managers.įFmpeg is a powerful tool that can do almost anything you can imagine with multimedia files.
It's available on many different operating systems and is included in some operating systems by default. In this article I'll be using FFmpeg through the command-line tool ffmpeg, which is only a single, small piece of the FFmpeg project. Despite its name, it has nothing to do with the Moving Picture Experts Group or the myriad multimedia formats it has created.
It's often used behind the scenes in many other media-related projects. Enter FFmpeg.įFmpeg is a collection of different projects for handling multimedia files. Tools like Audacity or Handbrake are fantastic, but sometimes you just want to change a file from one format into another quickly. There are many open source tools out there for editing, tweaking, and converting multimedia into exactly what you need.
0 kommentar(er)
