I am working on a software that receives an MJPEG stream from an IP camera and displays it on the screen. Now I'd like to record the stream at the same time in some movie format.
I'm still quite new to Java and got a little lost in the jungle of libraries etc. that are available. What I found was JMF but it looks terribly outdated and unmaintained.
Does anyone here have any suggestions for proper video encoding libraries (must at least support Linux, but OS independent would be perfect)?
Thanks.
Related
I want to create a media player in Java. The mp3 support already works with the JLayer library but which library can play m4a files?
I read about vlcj here on stackoverflow, but this seems to depend on Swing/AWT which I wouldn't use because I want to port the application to Android later on.
Have you looked at JAAD? It's a Javasound SPI that decodes AAC audio, I've used it with success previously.
Note that m4a is a container format, and while it usually contains (in my experience) AAC audio, in theory it could contain other formats instead.
You can find some information about getting it working without Javasound (and a test case) here.
This answer is indirect. I don't really know anything about m4a files. But what I have found is an open source library that can stream them as a flash server named red5. It's written in Java so theoretically you should be able to browse their code to figure out how to do it.
Hopefully someone here can give a more direct answer, this is the best I can do.
If you have Java 7 or later, you have access to the Javafx library. You can also use your media player (like iTunes or Windows Media Player) to convert to the simpler mp3 version and run that. I wouldn't recommend .wav files as they have significantly more data usage than mp3s, (which condense the file size by compressing the .wav data and omitting inaudible and otherwise garbage-y data).
import javafx.scene.media.*;
String name = "song.mp3";
Media song = new Media(name);
MediaPlayer player = new MediaPlayer(song);
player.play();
I am able to show the live streaming from my ip camera through jframe and applet , I need to convert this mpg stream to mp4 format so that i can show this in html5 video tag ..Can anybody suggest how to do that and video should be still live without any time lag ....One more thing to view streaming I am hitting the public ip of camera and this is how I am capturing video, is there any effect on the efficiency if large number of people are watching the video at the same time ..
Please suggest ...thanks in advance
First, know that you can't do live streaming with regular MP4 video format. "Progressive download" MP4 files have an index at the beginning of the file, this cannot be written before you finished encoding the entire movie. There is a variant of MP4 which indexes every small chunk of video separately, but it is not widely supported by HTML5 browsers.
I can suggest several options:
Use FLASH rather than HTML5 and convert the video to FLV. However, I'm not aware of a Java tool to do this conversion.
Use HTTP live streaming and set up a dedicated streaming server to do the transcoding. There is plenty of server software that can do that, such as Wowza server, Adobe FMS, and even Microsoft's Expression Encoder+IIS. You can also find SaaS solutions for that and EC2 images of such servers.
I am using the JSpeex API to convert a .wav file into .spx file. Everything goes perfect when tested on desktop; it took only 2 seconds.
Android developer used the same code but it took around 3 minutes to encode the same file on their simulator & phone. Is there any way to reduce this time for encoding? Code used to convert is as follows:
new JSpeexEnc().encode(new File("source.wav"), new File("dest.spx"));
Compression takes time. The better the compression, the longer it takes, and Speex is pretty good compression.
2 seconds of desktop computer time is absolutely ages.
JSpeex is a java implementation. Use a native implementation, ideally use the platform codecs, instead.
On phones, speech is best compressed using AMR - not necessarily the best quality/compression, but most likely hardware accelerated since its the format used by GSM. You can usually get AMR straight from the microphone.
How do you get large WAV files onto an Android device in the first place? If its actually the output of the microphone, consider using AMR as outlined above.
If you need Speex and you have a wav file, then consider sending it to a server for compression.
Canon/Nikon/other cameras save raw output of their sensor in some of their proprietary formats (.CR2, whatever). Is there any Java library designed to read them and convert into manageable BufferedImages?
I don't reqlly care here about fully customizable conversion similar to ufraw or imagemagick, rather something simple that "just works" for rendering simple previews of such images.
I've been where you are, and I feel for you. Your best bet is to use an Adobe or dcraw-based program to create thumbnails automatically. Temporary DNG files using Adobe's converter may be easier to use.
IF you insist on doing it in Java, you're about to run into a mountain of pain. RAW formats change often, have all sorts of crazy nuances and are intentionally hard to work with. Camera makers want you to use THEIR RAW conversion software, to show the camera's abilities at its best and screw Adobe. The guy behind dcraw found that some are camera manufacturers even use encryption now!
The existing Java libraries are poor -- JRawIO has improved since I last looked at it, but it supports only a fraction of the formats that dcraw does. In addition to the listed libraries, the imagero library may provide the ability to display a thumbnail for your image.
From personal experience, don't even think about writing your own RAW file reader.
I tried to do this with a very simple RAW format once (just a solid array of sensor data, 12 bits per pixel). The dcraw source translates badly to Java. You haven't seen such a nightmare of bit-fiddling ever. Took me days to debug problems with byte alignment and endian-ness.
jrawio is a plugin for Java Image I/O. With it you can read the raster data, the thumbnails and the metadata from the raw image file.
nef and cr2 already contains preview images in jpeg. just find the right offset and the right length to extract it...
Laurent Clevy # lclevy.free.fr/raw
Laurent
Unless you want to write you own file parser/loader (sounds fun imho ;) ), perhaps JMagick will help you. I haven't tried it and it might not work given your target platform since JMagick uses JNI.
UPDATE: dcraw looks like a good resource/reference
For the computer game I'm making, I obviously want to play sound. So far, I've been using AudioClip to play WAV files. While this approach works fine, the WAV files tend to be gigantic. A few seconds of sound end up being hundreds of kB. I'm faced with having a game download that's 95% audio!
The obvious option here would be to use MP3 or Ogg Vorbis. But I've had limited success with this - I can play MP3 using JLayer (but it plays in the same thread). As for Ogg, I've had no luck at all. Worse, JLayer's legal status is a bit on the dubious side.
So my question is to both Java developers and generally people who actually know something about sound: What do I do? Can I somehow "trim the fat" off my WAVs? Is there some way of playing Ogg in Java? Is there some other sound format I should use instead?
You could use JOrbis library to play back OGG music. For working sample usage you can look at these files here.
I also experimented with some lossless audio compression, for example I had a 16 bit mono sound. I separated the upper and lower bytes of each sample and put them after each other. Then I applied a differential replacement where each byte is replaced by its difference from the last byte. And finally used GZIP to compress the data. I was able to reduce the data size to 50-60% of the original size. Unfortunately this was not enough so I turned to the OGG format.
One thing I noticed with 8 bit music is that if I change the audio volume, the playback becomes very noisy. I solved this problem by upsampling the audio data to 16 bit right before the SourceDataLine.write().
These may be outdated, but they are officially recognized by the Xiph.org team (who maintain Ogg and Vorbis, among others).
http://www.vorbis.com/software/#java
The problem you describe is addressed by the Service Provider Interface (SPI) for sound in Java. The result is that simply adding JAR files to your classpath will add functionality to the default Java Sound API. Thus enabling the handling of more sound formats without changing code.
Last time I tried this the Javazoom people offered a working MP3 SPI JAR. Which was based on the JLayer you mentioned.
For Vorbis OGG there now also seems to be an SPI library. Check out the docs on the Vorbis SPI on Javazoom.
If you decide to stay with wav format...
It is probably not very important to have high quality sound files. You can use your favorite wav editor to lower the bit rate, switch to mono, or both. That will save tons of space and you won't notice the difference in quality while playing the game.
Hope this helps.