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ac-3 output from expansion module

jcavala

August 06, 2010 06:03

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So far, we have been unable to get the ac-3 5.1 audio output from the expansion module optical port. We have a correctly multiplexed mpg file but not having luck with the spdif. In the initialize video parameters section, we have: videoPlayer.SetAudioOutput(1) videoPlayer.MapDigitalOutput(1) videoPlayer.MapAudioMode(0) We have also done the above with videoPlayer.MapAudioMode(0) remmed out. In short, what will we need to do to get the raw ac-3 5.1 stream out the expansion module optical port? Thanks in advance

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4 comments

• 0
  
  jcavala August 06, 2010 06:06

  
  
  Sorry, I forgot to indicate we are using the 810 with latest firmware, project is video resolution 720 x 480
  
• 0
  
  RokuLyndon August 06, 2010 11:14

  
  
  You can get raw ac3 out, but the unit won't decode the ac3 for you.
  
  If you look at this thread on the expander:
  <!-- l --><a class="postlink-local" href="http://forums.roku.com/viewtopic.php?f=19&t=25245">viewtopic.php?f=19&t=25245</a><!-- l -->
  
  A. You should Set your audo output to 3. See list below.
  B. And, Map your digital output to 1. See second list below.
  
  

  
  SetAudioOutput(roInt audioout)
  In a playlist, this is the "audiooutput" keyword. In a csv file, this would be "videoplayeraudiooutput" or "audioplayeraudiooutput".
  The audio outputs are similar, though not identical to HD2000.
  0 - Analog. Output to onboard analog output or one of the 3 expander analog outputs.
  1 - USB. Output to USB audio, this is largely untested as yet.
  2 - Digital PCM. For playing decoded audio to either HDMI or expander SPDIF e.g. decoded MP3 files
  3 - Digital raw. For playing undecoded audio to either HDMI or expander SPDIF e.g. AC-3
  4 - Simultaneous onboard digital and onboard analog. I'm not aiming to do this for expander, only for onboard audio.

  
  
  
  

  MapDigitalOutput(roInt hdmi_or_spdif)
  This is new and isn't currently listed in csv files or playlists. But, this can be fixed easily.
  This picks which digital output is used from the 2 available:
  0 - HDMI
  1 - Expander SPDIF

  
  
• 0
  
  jcavala August 07, 2010 01:22

  
  
  Thanks -- I had uncovered that previous post, but had not quite fixed things. I used BrightAuthor to create the various files on the chip, then modified the Autorun.brs file to this:
     ' initialize video player parameters
     videoPlayer.SetPort(zone.msgPort)
     videoPlayer.SetViewMode(zone.viewMode%)
     videoPlayer.SetLoopMode(false)
     videoPlayer.SetAudioOutput(3)
     ' videoPlayer.SetAudioMode(zone.audioMode%)
     ' videoPlayer.MapStereoOutput(zone.audioMapping%)
     videoPlayer.MapDigitalOutput(1)
  Believe me it was a surprise when the audio appeared, but the spdif optical output is being decoded by a surround amp and working fine. My question now is what is the very simplest form of an autorun.brs file that can achieve the same results? I may wish only to loop an MPG file named "bal.mpg" on power up, or at most use a single gpio to start it. I think with a simple script like that as a "starter" I can find my way to more exotic controls.
  Thanks in advance.
  John
  
• 0
  
  RokuLyndon August 07, 2010 06:45

  
  
  Not sure what you're trying to do. This example below plays one video in a loop.
  
  
  p=createobject("roMessagePort")
  videoplayer = createobject("roVideoPlayer")
  videoplayer.SetPort(p)
  videoPlayer.SetAudioOutput(3)
  videoPlayer.MapDigitalOutput(1)
  
  
  loop:
  videoplayer.PlayFile("video.mpg")
  
  listen:
  if type(msg) = "roVideoEvent" then
  if msg.GetInt() = 8 then 'end of video
  goto loop
  endif
  endif
  goto listen