Discussion on the implementation of j2's Streaming Media Technology [2]

Cleverpig said "the reason why some media files in some formats do not support multipart playback is that they do not contain index information.
This is just like seek is not allowed to read files in sequence ..
This problem can be solved manually (orProgram.
"

And "with the release of itunes4.9, podcaster (pods) can build their own podcast and make it more attractive by adding slide-styled images. In addition, other podcast resources can be freely found using the URL in the additional information. This has become the "earthquake" in the podcast world ". At present, this feature is transplanted to a mobile phone by dividing the "chapter", that is, dividing the podcast resource file into multiple chapters, in this way, a mobile phone without the "replay/locating" capability can be played.

However, another challenge is to face mobile users. For example, mobile listening must manage interrupt events. When we start playing podcast for 20-40 minutes, a call or text message Suddenly arrives, which will force the playing to be interrupted. In this case, we can only re-open podcast to listen from the beginning or not in the mood to listen from the beginning. In addition, the media file format is also a nightmare for mobile users. Most mobile phones do not support MP3 or AAC podcast file formats, but they all support. 3GP standard AMR files. Moreover, mobile phones that can store a few megabytes of MP3 or AAC files are not very popular.

However, the javacast created by tea VUI Huang changes all of this. This software converts MP3 music to the. 3GP standard Amr (audio recording format) format that can be played by mobile phones. For more information, see http://www.ringtone4me.com.

Author of javacast-tea VUI Huang is also the author of mobcast, you have created a processing tool to convert podcast to a Java MIDlet (you only need to call javacast on your mobile phone to download this j2_app wirelessly and play podcast ). This allows those podcasters to easily obtain their podcast by simply adding a link to download the MIDlet. "

 

Huang's mobcast is indeed very famous. A few months ago, when I wrote toodoupodcastmidlet, I saw many people introduce him, but I couldn't connect him to http://www.geocities.com/tvhuangsg/mobcast.

Convert video to 3GP in various formats, and convert audio to amr in various formats. These can be done by hand under the open-source software mplayer. You only need to understand the various parameters of mplayer. Thanks to mplayer, I am also able to make mobile phones to watch live video of traffic. Thanks to mplayer developers!

"Mobile listening must manage interrupt events", which must be considered. When entering the paused status, you need to notify the playing thread to pause. At the same time, the connection thread should not capture the media data of the server. After the interface is switched back, the playing thread continues to replay, the connection thread continues to download music.

Bamboo says, "You can use manual (or program) to split files and deploy them on the server to solve the problem." I think that simple file splitting is not enough, or it is only applicable to the original data format of WAV. You should use mencoder to split a music file into a segment and put it on the server. mencoder can ensure independent playback when dealing with the format of each segment, in this way, you only need to follow the serial number to download the phone, and the server no longer needs to calculate and add header information.

In the middle of the US, if two players switch to play, there will be a snap in the middle.

 

Cleverpig said "If you are interested, you can watch jffmpeg. It is a java media framework that can process audio and video.
"And

"I thought for a moment and proposed the idea of" Mobile audio stream Gateway ": the server can use the" real-time "conversion format to convert MP3, WAV, and other formats of audio into the AMR format, of course, you can also perform segmentation. No matter what the audio source is (or even podcast), you can download it to your mobile phone. In this case, the server load is a problem, although the collected audio source does not need to be processed again. "

 

In fact, I originally wrote toodoupodcast, because the music formats provided by those podcasts do not match those provided by mobile phones, therefore, I use a Java Web service such as toodoupodcast to call the FFMPEG tool for audio conversion. The conversion format is indeed a very CPU resource-consuming task, and it takes a long time. If there are many users, it will put a lot of pressure on the server.
Now we do a good job of segmentation, which is more suitable for mobile users.

Jffmpeg should be a Java encapsulation of the tool written in ffmpeg c.

Another encapsulation is
Http://fobs.sourceforge.net/
FOBs, the C ++ & JMF wrapper for FFMPEG.