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JAVE(Java Audio Video Encoder)是ffmpeg项目的一个Java封装。可以利用JAVE在不同的视频与音频格式之间相互转换。比如能够将AVI文件转换成MPEG格式的文件,分离和转换视频与音频轨道,压缩视频,改变大小和比例。
JAVE manual
Installation and requirementsAudio/video encodingEncoding attributes Audio encoding attributes Video encoding attributesMonitoring the transcoding operationTranscoding failuresGetting informations about a multimedia fileUsing an alternative ffmpeg executableSupported container formatsBuilt-in decoders and encodersExamples
Installation and requirements
In order to use JAVE in your Java application, you have to add the file jave-1.0.jar in your application CLASSPATH.
JAVE runs on a Java Runtime Environment J2SE v.1.4 or later.
JAVE includes and uses a ffmpeg executable built for Windows and Linux operating systems on i386/32 bit hardware platforms. In order to run JAVE on other platforms you have to replace the built-in ffmpeg executable with another one suitable for your needs. This is very simple, once you have built your own ffmpeg binaries. The operation is described in the “Using an alternative ffmpeg executable” section.
Audio/video encodingThe most important JAVE class is it.sauronsoftware.jave.Encoder. Encoder objects expose many methods for multimedia transcoding. In order to use JAVE, you always have to create an Encoder istance:
Encoder encoder = new Encoder();
Once the instance has been created, you can start transcoding calling the encode() method:
public void encode(java.io.File source,
java.io.File target, it.sauronsoftware.jave.EncodingAttributes attributes) throws java.lang.IllegalArgumentException, it.sauronsoftware.jave.InputFormatException, it.sauronsoftware.jave.EncoderExceptionThe first parameter, source, represents the source file to decode.
The second parameter, target, is the target file that will be created and encoded.
The attributes parameter, whose type is it.sauronsoftware.jave.EncodingAttributes, is a data structure containing any information needed by the encoder.
Please note that a call to encode() is a blocking one: the method will return only once the transcoding operation has been completed (or failed). If you are interested in monitoring the transcoding operation take a look to the “Monitoring the transcoding operation” section.
Encoding attributesTo specify your preferences about the transcoding operation you have to supply an it.sauronsoftware.jave.EncodingAttributes instance to the encode() call. You can create your own EncodingAttributes instance, and you can populate it with the following methods:
public void setAudioAttributes(it.sauronsoftware.jave.AudioAttributes audioAttributes)It sets the audio encoding attributes. If never called on a new EncodingAttributes instance, or if the given parameter is null, no audio stream will be included in the encoded file. See also "Audio encoding attributes".public void setVideoAttributes(it.sauronsoftware.jave.AudioAttributes videoAttributes)It sets the video encoding attributes. If never called on a new EncodingAttributes instance, or if the given parameter is null, no video stream will be included in the encoded file. See also "Video encoding attributes".public void setFormat(java.lang.String format)It sets the format of the streams container that will be used for the new encoded file. The given parameter represents the format name. An encoding format name is valid and supported only if it appears in the list returned by the getSupportedEncodingFormats() method of the Encoder instance in use.public void setOffset(java.lang.Float offset)It sets an offset for the transcoding operation. The source file will be re-encoded starting at offset seconds since its beginning. In example if you'd like to cut the first five seconds of the source file, you should call setOffset(5) on the EncodingAttributes object passed to the encoder.public void setDuration(java.lang.Float duration)It sets a duration for the transcoding operation. Only duration seconds of the source will be re-encoded in the target file. In example if you'd like to extract and transcode a portion of thirty seconds from the source, you should call setDuration(30) on the EncodingAttributes object passed to the encoder.
Audio encoding attributes
Audio encoding attributes are represented by the instances of the it.sauronsoftware.jave.AudioAttributes class. The available methods on this kind of objects are:
public void setCodec(java.lang.String codec)It sets the name of the codec that will be used for the transcoding of the audio stream. You have to choose a value from the list returned by the getAudioEncoders() method of the current Encoder instance. Otherwise you can pass the AudioAttributes.DIRECT_STREAM_COPY special value, that requires the copy of the original audio stream from the source file.public void setBitRate(java.lang.Integer bitRate)It sets the bitrate value for the new re-encoded audio stream. If no bitrate value is set, a default one will be picked by the encoder. The value should be expressed in bits per second. In example if you want a 128 kb/s bitrate you should call setBitRate(new Integer(128000)).public void setSamplingRate(java.lang.Integer bitRate)It sets the sampling rate for the new re-encoded audio stream. If no sampling-rate value is set, a default one will be picked by the encoder. The value should be expressed in hertz. In example if you want a CD-like 44100 Hz sampling-rate, you should call setSamplingRate(new Integer(44100)).public void setChannels(java.lang.Integer channels)It sets the number of the audio channels that will be used in the re-encoded audio stream (1 = mono, 2 = stereo). If no channels value is set, a default one will be picked by the encoder.public void setVolume(java.lang.Integer volume)This method can be called to alter the volume of the audio stream. A value of 256 means no volume change. So a value less than 256 is a volume decrease, while a value greater than 256 will increase the volume of the audio stream.
Video encoding attributes
Video encoding attributes are represented by the instances of the it.sauronsoftware.jave.VideoAttributes class. The available methods on this kind of objects are:
public void setCodec(java.lang.String codec)It sets the name of the codec that will be used for the transcoding of the video stream. You have to choose a value from the list returned by the getVideoEncoders() method of the current Encoder instance. Otherwise you can pass the VideoAttributes.DIRECT_STREAM_COPY special value, that requires the copy of the original video stream from the source file.public void setTag(java.lang.String tag)It sets the tag/fourcc value associated to the re-encoded video stream. If no value is set a default one will be picked by the encoder. The tag value is often used by multimedia players to choose which video decoder run on the stream. In example a MPEG 4 video stream with a "DIVX" tag value will be decoded with the default DivX decoder used by the player. And, by the way, this is exactly what a DivX is: a MPEG 4 video stream with an attached "DIVX" tag/fourcc value!public void setBitRate(java.lang.Integer bitRate)It sets the bitrate value for the new re-encoded video stream. If no bitrate value is set, a default one will be picked by the encoder. The value should be expressed in bits per second. In example if you want a 360 kb/s bitrate you should call setBitRate(new Integer(360000)).public void setFrameRate(java.lang.Integer bitRate)It sets the frame rate value for the new re-encoded audio stream. If no bitrate frame-rate is set, a default one will be picked by the encoder. The value should be expressed in frames per second. In example if you want a 30 f/s frame-rate you should call setFrameRate(new Integer(30)).public void setSize(it.sauronsoftware.jave.VideoSize size)It sets the size and the proportion of the images in the video stream. If no value is set, the encoder will preserve the original size and proportion. Otherwise you can pass a it.sauronsoftware.java.VideoSize instance, with your preferred size. You can set the width and the height of the new encoded video, with pixel values, scaling the original one. In example if you want to scale the video to 512 px in width and 384px in height you should call setSize(new VideoSize(512, 384)).
Monitoring the transcoding operation
You can monitor a transcoding operation with a listener. JAVE defines the it.sauronsoftware.jave.EncoderProgressListener interface. This interface could be implemented by your application, and concrete EncoderProgressListener instances can be passed to the encoder. The encoder will call your listener methods every time a significant event occurs. To pass an EncoderProgressListener to the encoder you should use this definition of the encode() method:
public void encode(java.io.File source,
java.io.File target, it.sauronsoftware.jave.EncodingAttributes attributes, it.sauronsoftware.jave.EncoderProgressListener listener) throws java.lang.IllegalArgumentException, it.sauronsoftware.jave.InputFormatException, it.sauronsoftware.jave.EncoderExceptionTo implemen the EncoderProgressListener interface you have to define all of the following methods:
public void sourceInfo(it.sauronsoftware.jave.MultimediaInfo info)The encoder calls this method after the source file has been analized. The info parameter is an instance of the it.sauronsoftware.jave.MultimediaInfo class and it represents informations about the source audio and video streams and their container.public void progress(int permil)This method is called by the encoder every time a progress in the encoding operation has been done. The permil parameter is a value representing the point reached by the current operation and its range is from 0 (operation just started) to 1000 (operation completed).public void message(java.lang.String message)This method is called by the encoder to notify a message regarding the transcoding operation (usually the message is a warning).
Transcoding failures
Of course, a transcoding operation could fail. Then the encode() method will propagate an exception. Depending on what is happened, the exception will be one of the following:
java.lang.IllegalArgumentExceptionThe transcoding operation has never started since the encoding attributes passed to the encoder has been recognized as invalid. Usualy this occurs when the EncodingAttributes instance given to the encoder asks the encoding of a container with no audio and no video streams (both AudioAttributes and VideoAttribues attributes are null or not set).it.sauronsoftware.jave.InputFormatExceptionThe source file can't be decoded. It occurs when the source file container, the video stream format or the audio stream format are not supported by the decoder. You can check for supported containers and plugged decoders calling the encoder methods getSupportedDecodingFormats(), getAudioDecoders() and getVideoDecoders().it.sauronsoftware.jave.EncoderExpectionThe operation has failed during the trancoding due to an internal error. You should check the exception message, and you can also use an EncoderProgressListener instance to check any message issued by the encoder.
Getting informations about a multimedia file
You can get informations about an existing multimedia file before transcoding it, calling the encoder getInfo() method. The getInfo() method gives you informations about the container used by the file and about its wrapped audio and video streams:
public it.sauronsoftware.jave.MultimediaInfo getInfo(java.io.File source)
throws it.sauronsoftware.jave.InputFormatException, it.sauronsoftware.jave.EncoderExceptionAn it.sauronsoftware.jave.MultimediaInfo object encapsulates information on the whole multimedia content and its streams, using instances of it.sauronsoftware.jave.AudioInfo and it.sauronsoftware.jave.VideoInfo to describe the wrapped audio and video. These objects are similar to the EncodingAttributes, AudioAttributes and VideoAttributes ones, but they works in a read-only mode. Check the JAVE API javadoc documentation, bundled with the JAVE distribution, to gain more details about them.
Using an alternative ffmpeg executableJAVE is not pure Java: it acts as a wrapper around an ffmpeg () executable. ffmpeg is an open source and free software project entirely written in C, so its executables cannot be easily ported from a machine to another. You need a pre-compiled version of ffmpeg in order to run JAVE on your target machine. The JAVE distribution includes two pre-compiled executables of ffmpeg: a Windows one and a Linux one, both compiled for i386/32 bit hardware achitectures. This should be enough in most cases. If it is not enough for your specific situation, you can still run JAVE, but you need to obtain a platform specific ffmpeg executable. Check the Internet for it. You can even build it by yourself getting the code (and the documentation to build it) on the official ffmpeg site. Once you have obtained a ffmpeg executable suitable for your needs, you have to hook it in the JAVE library. That’s a plain operation. JAVE gives you an abstract class called it.sauronsoftware.jave.FFMPEGLocator. Extend it. All you have to do is to define the following method:
public java.lang.String getFFMPEGExecutablePath()
This method should return a file system based path to your custom ffmpeg executable.
Once your class is ready, suppose you have called it MyFFMPEGExecutableLocator, you have to create an alternate encoder that uses it instead of the default locator:
Encoder encoder = new Encoder(new MyFFMPEGExecutableLocator())
You can use the same procedure also to switch to other versions of ffmpeg, even if you are on a platform covered by the executables bundled in the JAVE distribution.
Anyway be careful and test ever your application: JAVE it’s not guaranteed to work properly with custom ffmpeg executables different from the bundled ones.
Supported container formatsThe JAVE built-in ffmpeg executable gives support for the following multimedia container formats:
Decoding Formato Descrizione 4xm 4X Technologies format MTV MTV format RoQ Id RoQ format aac ADTS AAC ac3 raw ac3 aiff Audio IFF alaw pcm A law format amr 3gpp amr file format apc CRYO APC format ape Monkey’s Audio asf asf format au SUN AU Format avi avi format avs AVISynth bethsoftvid Bethesda Softworks ‘Daggerfall’ VID format c93 Interplay C93 daud D-Cinema audio format dsicin Delphine Software International CIN format dts raw dts dv DV video format dxa dxa ea Electronic Arts Multimedia Format ea_cdata Electronic Arts cdata ffm ffm format film_cpk Sega FILM/CPK format flac raw flac flic FLI/FLC/FLX animation format flv flv format gif GIF Animation gxf GXF format h261 raw h261 h263 raw h263 h264 raw H264 video format idcin Id CIN format image2 image2 sequence image2pipe piped image2 sequence ingenient Ingenient MJPEG ipmovie Interplay MVE format libnut nut format m4v raw MPEG4 video format matroska Matroska File Format mjpeg MJPEG video mm American Laser Games MM format mmf mmf format mov,mp4,m4a,3gp,3g2,mj2 QuickTime/MPEG4/Motion JPEG 2000 format mp3 MPEG audio layer 3 mpc musepack mpc8 musepack8 mpeg MPEG1 System format mpegts MPEG2 transport stream format mpegtsraw MPEG2 raw transport stream format mpegvideo MPEG video mulaw pcm mu law format mxf MXF format nsv NullSoft Video format nut nut format nuv NuppelVideo format ogg Ogg format psxstr Sony Playstation STR format rawvideo raw video format redir Redirector format rm rm format rtsp RTSP input format s16be pcm signed 16 bit big endian format s16le pcm signed 16 bit little endian format s8 pcm signed 8 bit format sdp SDP shn raw shorten siff Beam Software SIFF smk Smacker Video sol Sierra SOL Format swf Flash format thp THP tiertexseq Tiertex Limited SEQ format tta true-audio txd txd format u16be pcm unsigned 16 bit big endian format u16le pcm unsigned 16 bit little endian format u8 pcm unsigned 8 bit format vc1 raw vc1 vmd Sierra VMD format voc Creative Voice File format wav wav format wc3movie Wing Commander III movie format wsaud Westwood Studios audio format wsvqa Westwood Studios VQA format wv WavPack yuv4mpegpipe YUV4MPEG pipe format Encoding Formato Descrizione 3g2 3gp2 format 3gp 3gp format RoQ Id RoQ format ac3 raw ac3 adts ADTS AAC aiff Audio IFF alaw pcm A law format amr 3gpp amr file format asf asf format asf_stream asf format au SUN AU Format avi avi format crc crc testing format dv DV video format dvd MPEG2 PS format (DVD VOB) ffm ffm format flac raw flac flv flv format framecrc framecrc testing format gif GIF Animation gxf GXF format h261 raw h261 h263 raw h263 h264 raw H264 video format image2 image2 sequence image2pipe piped image2 sequence libnut nut format m4v raw MPEG4 video format matroska Matroska File Format mjpeg MJPEG video mmf mmf format mov mov format mp2 MPEG audio layer 2 mp3 MPEG audio layer 3 mp4 mp4 format mpeg MPEG1 System format mpeg1video MPEG video mpeg2video MPEG2 video mpegts MPEG2 transport stream format mpjpeg Mime multipart JPEG format mulaw pcm mu law format null null video format nut nut format ogg Ogg format psp psp mp4 format rawvideo raw video format rm rm format rtp RTP output format s16be pcm signed 16 bit big endian format s16le pcm signed 16 bit little endian format s8 pcm signed 8 bit format svcd MPEG2 PS format (VOB) swf Flash format u16be pcm unsigned 16 bit big endian format u16le pcm unsigned 16 bit little endian format u8 pcm unsigned 8 bit format vcd MPEG1 System format (VCD) vob MPEG2 PS format (VOB) voc Creative Voice File format wav wav format yuv4mpegpipe YUV4MPEG pipe format Built-in decoders and encodersThe JAVE built-in ffmpeg executable contains the following decoders and encoders:
Audio decoders adpcm_4xm adpcm_adx adpcm_ct adpcm_ea adpcm_ea_r1 adpcm_ea_r2 adpcm_ea_r3 adpcm_ea_xas adpcm_ima_amv adpcm_ima_dk3 adpcm_ima_dk4 adpcm_ima_ea_eacs adpcm_ima_ea_sead adpcm_ima_qt adpcm_ima_smjpeg adpcm_ima_wav adpcm_ima_ws adpcm_ms adpcm_sbpro_2 adpcm_sbpro_3 adpcm_sbpro_4 adpcm_swf adpcm_thp adpcm_xa adpcm_yamaha alac ape atrac 3 cook dca dsicinaudio flac g726 imc interplay_dpcm liba52 libamr_nb libamr_wb libfaad libgsm libgsm_ms mace3 mace6 mp2 mp3 mp3adu mp3on4 mpc sv7 mpc sv8 mpeg4aac nellymoser pcm_alaw pcm_mulaw pcm_s16be pcm_s16le pcm_s16le_planar pcm_s24be pcm_s24daud pcm_s24le pcm_s32be pcm_s32le pcm_s8 pcm_u16be pcm_u16le pcm_u24be pcm_u24le pcm_u32be pcm_u32le pcm_u8 pcm_zork qdm2 real_144 real_288 roq_dpcm shorten smackaud sol_dpcm sonic truespeech tta vmdaudio vorbis wavpack wmav1 wmav2 ws_snd1 xan_dpcm Audio encoders ac3 adpcm_adx adpcm_ima_wav adpcm_ms adpcm_swf adpcm_yamaha flac g726 libamr_nb libamr_wb libfaac libgsm libgsm_ms libmp3lame libvorbis mp2 pcm_alaw pcm_mulaw pcm_s16be pcm_s16le pcm_s24be pcm_s24daud pcm_s24le pcm_s32be pcm_s32le pcm_s8 pcm_u16be pcm_u16le pcm_u24be pcm_u24le pcm_u32be pcm_u32le pcm_u8 pcm_zork roq_dpcm sonic sonicls vorbis wmav1 wmav2 Video decoders 4xm 8bps VMware video aasc amv asv1 asv2 avs bethsoftvid bmp c93 camstudio camtasia cavs cinepak cljr cyuv dnxhd dsicinvideo dvvideo dxa ffv1 ffvhuff flashsv flic flv fraps gif h261 h263 h263i h264 huffyuv idcinvideo indeo2 indeo3 interplayvideo jpegls kmvc loco mdec mjpeg mjpegb mmvideo mpeg1video mpeg2video mpeg4 mpegvideo msmpeg4 msmpeg4v1 msmpeg4v2 msrle msvideo1 mszh nuv pam pbm pgm pgmyuv png ppm ptx qdraw qpeg qtrle rawvideo roqvideo rpza rv10 rv20 sgi smackvid smc snow sp5x svq1 svq3 targa theora thp tiertexseqvideo tiff truemotion1 truemotion2 txd ultimotion vb vc1 vcr1 vmdvideo vp3 vp5 vp6 vp6a vp6f vqavideo wmv1 wmv2 wmv3 wnv1 xan_wc3 xl zlib zmbv Video encoders asv1 asv2 bmp dnxhd dvvideo ffv1 ffvhuff flashsv flv gif h261 h263 h263p huffyuv jpegls libtheora libx264 libxvid ljpeg mjpeg mpeg1video mpeg2video mpeg4 msmpeg4 msmpeg4v1 msmpeg4v2 pam pbm pgm pgmyuv png ppm qtrle rawvideo roqvideo rv10 rv20 sgi snow svq1 targa tiff wmv1 wmv2 zlib zmbv ExamplesFrom a generic AVI to a youtube-like FLV movie, with an embedded MP3 audio stream:
File source = new File(“source.avi”);
File target = new File(“target.flv”); AudioAttributes audio = new AudioAttributes(); audio.setCodec(“libmp3lame”); audio.setBitRate(new Integer(64000)); audio.setChannels(new Integer(1)); audio.setSamplingRate(new Integer(22050)); VideoAttributes video = new VideoAttributes(); video.setCodec(“flv”); video.setBitRate(new Integer(160000)); video.setFrameRate(new Integer(15)); video.setSize(new VideoSize(400, 300)); EncodingAttributes attrs = new EncodingAttributes(); attrs.setFormat(“flv”); attrs.setAudioAttributes(audio); attrs.setVideoAttributes(video); Encoder encoder = new Encoder(); encoder.encode(source, target, attrs);Next lines extracts audio informations from an AVI and store them in a plain WAV file:
File source = new File(“source.avi”);
File target = new File(“target.wav”); AudioAttributes audio = new AudioAttributes(); audio.setCodec(“pcm_s16le”); EncodingAttributes attrs = new EncodingAttributes(); attrs.setFormat(“wav”); attrs.setAudioAttributes(audio); Encoder encoder = new Encoder(); encoder.encode(source, target, attrs);Next example takes an audio WAV file and generates a 128 kbit/s, stereo, 44100 Hz MP3 file:
File source = new File(“source.wav”);
File target = new File(“target.mp3”); AudioAttributes audio = new AudioAttributes(); audio.setCodec(“libmp3lame”); audio.setBitRate(new Integer(128000)); audio.setChannels(new Integer(2)); audio.setSamplingRate(new Integer(44100)); EncodingAttributes attrs = new EncodingAttributes(); attrs.setFormat(“mp3”); attrs.setAudioAttributes(audio); Encoder encoder = new Encoder(); encoder.encode(source, target, attrs);Next one decodes a generic AVI file and creates another one with the same video stream of the source and a re-encoded low quality MP3 audio stream:
File source = new File(“source.avi”);
File target = new File(“target.avi”); AudioAttributes audio = new AudioAttributes(); audio.setCodec(“libmp3lame”); audio.setBitRate(new Integer(56000)); audio.setChannels(new Integer(1)); audio.setSamplingRate(new Integer(22050)); VideoAttributes video = new VideoAttributes(); video.setCodec(VideoAttributes.DIRECT_STREAM_COPY); EncodingAttributes attrs = new EncodingAttributes(); attrs.setFormat(“avi”); attrs.setAudioAttributes(audio); attrs.setVideoAttributes(video); Encoder encoder = new Encoder(); encoder.encode(source, target, attrs);Next one generates an AVI with MPEG 4/DivX video and OGG Vorbis audio:
File source = new File(“source.avi”);
File target = new File(“target.avi”); AudioAttributes audio = new AudioAttributes(); audio.setCodec(“libvorbis”); VideoAttributes video = new VideoAttributes(); video.setCodec(“mpeg4”); video.setTag(“DIVX”); video.setBitRate(new Integer(160000)); video.setFrameRate(new Integer(30)); EncodingAttributes attrs = new EncodingAttributes(); attrs.setFormat(“mpegvideo”); attrs.setAudioAttributes(audio); attrs.setVideoAttributes(video); Encoder encoder = new Encoder(); encoder.encode(source, target, attrs);A smartphone suitable video:
File source = new File(“source.avi”);
File target = new File(“target.3gp”); AudioAttributes audio = new AudioAttributes(); audio.setCodec(“libfaac”); audio.setBitRate(new Integer(128000)); audio.setSamplingRate(new Integer(44100)); audio.setChannels(new Integer(2)); VideoAttributes video = new VideoAttributes(); video.setCodec(“mpeg4”); video.setBitRate(new Integer(160000)); video.setFrameRate(new Integer(15)); video.setSize(new VideoSize(176, 144)); EncodingAttributes attrs = new EncodingAttributes(); attrs.setFormat(“3gp”); attrs.setAudioAttributes(audio); attrs.setVideoAttributes(video); Encoder encoder = new Encoder(); encoder.encode(source, target, attrs);官网:
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