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bmckim's avatar
bmckim
Visitor
15 years ago

Rhozet Carbon Coder Preset + Encoding h264 HLS

We are currently working with Rhozet (http://www.rhozet.com/carbon_coder.html) tech support to help them tune their HLS preset. Their current preset works fine with the iPhone/iPad, but the Roku runs into trouble. We have found that different h264 settings cause the Roku to stutter during playback, however have not been able to pinpoint which. Does Roku have a definitive h264 advanced encode guide? Or does anyone know if there are specific settings the Roku has trouble with?
Roku Developer Program

2 Replies

  • RokuKevin's avatar
    RokuKevin
    Visitor
    15 years ago
    The encoding quide is in the SDK contains this info:

    % cat /usr/share/ffmpeg/libx264-roku.ffpreset
    coder=1
    flags=+loop
    cmp=+chroma
    partitions=+parti8x8+parti4x4+partp8x8+partb8x8
    me_method=umh
    subq=8
    me_range=16
    g=250
    keyint_min=25
    sc_threshold=40
    i_qfactor=0.71
    b_strategy=2
    qcomp=0.6
    qmin=10
    qmax=51
    qdiff=4
    bf=4
    refs=4
    directpred=3
    trellis=1
    flags2=+wpred+mixed_refs+dct8x8+fastpskip
  • bmckim's avatar
    bmckim
    Visitor
    15 years ago
    Thanks, Kevin. With the newest update of Carbon Coder they have fixed the issue and using their HLS preset produces files that play very well on the Roku.