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Hi all:<BR> <BR> I'm developing a rtp receiving directshow filter, using live555<BR>as the rtp/rtsp module. I adopt the Apple's Darwin streaming server.<BR>At first, I converted a media file to 3gp format named as mov1.3gp <BR>using QuickTime Pro, with video format is H.263 and audio is AAC-LC.<BR>Then I can receive the stream and play it well.<BR> <BR>
Yesterday, I converted a media file using ffmpeg,not Quick<BR>Time Pro,I selected the H263 video format and AAC(using option:<BR>-acodec libfaac),I put the file on server to steam it. On the client<BR>I can receive both video and audio RTP packets,But can only play video.<BR>I checked the SDP data from server,found that when server streams <BR>media file generated by QT Pro,the audio is "MP4A-LATM",and when <BR>streams file generated by ffmpeg,audio is "mpeg4-generic".<BR><BR>
The first 3gp file was converted and hinted by QT Pro,The <BR>Second was converted by ffmpeg and hinted by mp4creator.<BR>
<BR>
I can make sure that both media files have the same AAC<BR>audio format. Someone could tell me why the same format ,but different<BR>way server streams them? And , the other question is ,what exectly<BR>is the difference between "MP4A-LATM" and "mpeg4-generic".<BR>
Thanks in advance..<BR>
<BR>
Bruce<BR><br /><hr />更多热辣资讯尽在新版MSN首页！ <a href='http://cn.msn.com/' target='_new'>立刻访问！</a></body>
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