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Message: <blockquote data-quote="j1nx" data-source="post: 681034" data-attributes="member: 13808">VLC: Figured out all settings needed to create an iPhone compatible mp4 file. Streamed it with the livehttp module of VLC, still stuttering while playback on my ipod. Again opening the fragments manually with an other PC based player does not show this stuttering. I guess VLC is not yet mature enough to handle all the way it should.Anyway, if someone would want to have a look, this is what I came up with;[code]--sout=#transcode{vcodec=h264,vb=256,width=320,height=240,fps=25,deinterlace,acodec=mp4a,ab=96,channels=2,samplerate=44100,audio-sync,venc=x264{aud,profile=baseline,level=30,keyint=30,bframes=0,ref=1,crf=24,deblock=0:0,qpmin=10,qpmax=51,partitions=fast,me=hex,merange=4,subme=2,trellis=0,nocabac}[/code]archive_segment_length: I think this is not working at the moment (bug), tried different seconds, but the ismv file is not rolled to the next.dvr_window_length: This is the amount of second the playing should start in the past compared to where the encoding takes place. 15 means, you will start playing 15 before the frame it is actually encoding at the moment.Smooth Streaming, segments length: I now understand how smoothstreaming handles the segment lengths. The video will be splitted at the keyframes.[code]g=100keyint_min=50sc_threshold=0[/code]So what does this do? g=100, this means we want a key frame every 100 frames. Considering PAL fps of 25 this means about every 4 seconds.sc_threshold=0, This means we want zero tolerance if it comes to where to put this key frame. It is normally not wise to insert a key frame in the middle of a scene. Increasing this number allows a margin, putting the key frame at a scene cut, instead of in the middle of a scene.keyint_min=50, If we allow a margin in the key frame placement, this number means. the minimal distance between two key frames. Pal fps of 25 means at least every 2 seconds.As Smooth Streaming also uses this key frames as segment lengths, this means every segment is at least keyint_min/fps seconds, up to q(g+sc_threshold)/fps. If you have only one quality stream, you can increase the sc_threshold back to the default of 40. Later if more quality streams are provided, this has to be zero because you want all the different quality segments to be exactly the same.I also now understand most, if not all of the quality parameters of ffmpeg and why cbr is not really cbr and which values you can tweak to have more consistent bit rates. I will update my first post at my other thread later, explaining all ffmpeg and smooth streaming settings and give maybe 3 pre-settings (fast, medium, slow). Just need some time to write it down properly.Two comments so far from my side; Apple advises to use ~10 second fragments, so it might be better to use;[code]g=250keyint_min=250sc_threshold=40[/code]Secondly Apple advises to use up to 44100 for the audio,so maybe it is better to lower the 48000 to 44100. Will do some additional testing later. Keep you informed.</blockquote>

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