Java library to check a video's metadata (if it's 1080p, 720p, etc) [closed]

问题

I'm currently looking for a library that looks at a videos metadata and see if the video is 1080p, 720p or a least be able get the basic metadata(resolution, bitrate, etc) so I could do the calculations to check myself.

I'm hoping the library is light in size, cross platform and it can support a number of the main formats. Something like https://github.com/drewnoakes/metadata-extractor but of course for videos.

I tried searching around and found nothing, does such a library exist?

回答1:

Try these api's :

Java Media Frame Work [Tutorial]
jffmpeg
jvlc
vlcj
gstreamer-java
Fobs4JMF
Video4Linux4Java

回答2:

I haven't tried it yet, but seems Java MP4 Parser library is what I've been looking for. It is able to read and edit metadata, cross platform and seems to be light in file size.

An excerpt from the github documentation:

Java MP4 Parser

A Java API to read, write and create MP4 container. Manipulating containers is different from encoding and decoding videos and audio. Using the library

The library is published to Maven repositories. Each release is pushed to a staging repository which is published on the release page. On request specific releases can be pushed to maven central.
  <dependency>
    <groupId>com.googlecode.mp4parser</groupId>
    <artifactId>isoparser</artifactId>
    <version>1.1.7</version>
  </dependency>
For projects that do not use a dependency management tool each release's artifacts (jar, javadoc-jar, source-jar) are attached to the release page. Please be aware that the project requires the aspectj-rt.jar library.

What can you do?

Typical tasks for the MP4 Parser are:

Muxing audio/video into an MP4 file

Append recordings that use same encode settings

Adding/Changing metadata

Shorten recordings by omitting frames My examples will all use H264 and AAC as these two codecs are most typical for MP4 files. AC-3 is also not uncommon as the codec is well known from DVD. There are also MP4 files with H263/MPEG-2 video tracks but they are no longer used widespread as most android phones. You can also

Muxing Audio/Video

The API and the process is straight-forward:

You wrap each raw format file into an appropriate Track object.

H264TrackImpl h264Track = new H264TrackImpl(new FileDataSourceImpl("video.h264")); AACTrackImpl aacTrack = new AACTrackImpl(new FileDataSourceImpl("audio.aac"));

These Track object are then added to a Movie object
Movie movie = new Movie();
movie.addTrack(h264Track);
movie.addTrack(aacTrack);
The Movie object is fed into an MP4Builder to create the container.
Container mp4file = new DefaultMp4Builder().build(movie);
Write the container to an appropriate sink.

FileChannel fc = new FileOutputStream(new File("output.mp4")).getChannel(); mp4file.writeContainer(fc); fc.close(); There are cases where the frame rate is signalled out of band or is known in advance so that the H264 doesn't contain it literally. In this case you will have to supply it to the constructor.

There are Track implementations for the following formats:

H264

AAC

AC3

EC3

and additionally two subtitle tracks that do not directly wrap a raw format but they are conceptually similar.

Typical Issues

Audio and video are not in sync. Whenever there are problems with timing possible make sure to start

Audio starts before video

In AAC there are always samplerate/1024 sample/s so each sample's duration is 1000 * 1024 / samplerate milliseconds.

48KHz => ~21.3ms

44.1KHz => ~23.2ms

By omitting samples from the start you can easily shorten the audio track. Remove as many as you need. You will not be able to match audio and video exactly with that but the human perception is more sensible to early audio than to late audio.

Remember: If someone is only 10 meters away the delay between audio and video is >30ms. The brain is used to that!

AACTrackImpl aacTrackOriginal = new AACTrackImpl(new FileDataSourceImpl("audio.aac")); // removes the first sample and shortens the AAC track by ~22ms CroppedTrack aacTrackShort = new CroppedTrack(aacTrackOriginal, 1, aacTrack.getSamples().size());

Append Recordings with Same Encode Settings

It is important to emphasize that you cannot append any two tracks with:

Different resolutions

Different frame-rates

What can't you do?

Create JPEGs from a movie. No - this is no decoder. The MP4 Parser doesn't know how to do that. Create a movie from JPEGs

来源：https://stackoverflow.com/questions/7142645/java-library-to-check-a-videos-metadata-if-its-1080p-720p-etc

标签

java

video

metadata