Issues playing back a WMV file

I don't think there's anything wrong with your server. There's something about the wmv file the Roku doesn't like, but I can't see what it is. wmv isn't really my thing.

-JT

If I had to guess, I'd say it's most likely the audio codec that's causing the problem. According to VLC, that file is using "Windows Media Audio 2", and per the SDK documentation, the Roku only supports "WMA 9.2 (CBR)" for WMV files. The behavior you're describing sounds pretty much identical to what happens when trying to play an HLS stream with an unsupported audio codec (i.e., no error, just infinite buffering), which would support that theory.

If I play the file with Windows Media Player and I select "Properties" in the player, it shows me the codecs for the file:

audio codec: Windows Media Audio 9.2 48 kbps, 32 kHz, stereo 1-pass CBR

video codec: VC-1 VC-1 Advanced Profile

I don't believe it's an issue with the codecs as both of those codecs are listed in the 2.8 SDK as supported.

I have also used "asfbin" (which is a very good asf file parser and fixer) to check for any file errors and the file checks out as being properly formatted.

"HectorH" wrote:
If I play the file with Windows Media Player and I select "Properties" in the player, it shows me the codecs for the file:

audio codec: Windows Media Audio 9.2 48 kbps, 32 kHz, stereo 1-pass CBR

video codec: VC-1 VC-1 Advanced Profile

I don't believe it's an issue with the codecs as both of those codecs are listed in the 2.8 SDK as supported.

I have also used "asfbin" (which is a very good asf file parser and fixer) to check for any file errors and the file checks out as being properly formatted.

Oops.. sorry about that. I wonder why VLC is reporting it as WMA 2... :?
The behavior is still very similar to what I described above, so I would still guess it's something like that that's tripping up the decoder, otherwise I'd expect an error, instead of the infinite buffer.

"HectorH" wrote:
I don't believe it's an issue with the codecs as both of those codecs are listed in the 2.8 SDK as supported.

I don't believe it's an issue with your server because I can download the file and use my server and I get the same results as you. Your server appears to support the range requests that are required. If you're set on using wmv files, you may have to wait until the Roku guys return on Monday and let one of them take a look at your file. Otherwise, you could re-encode the file as an MPEG-4.

-JT

Both WMV and MPEG-4 support are a requirement.

I can serve MP4 VOD files quite well. I'm still experimenting with Live AVC delivery via HLS, but I haven't ruled out my own bugs, so I'm not ready to post about those issues yet.

The only place I have ran out of ideas is with WMV VOD playback.

We'll see what the Roku guys say on Monday.

Thanks!

If you FFWD a minute or so into the video will it play?

If it does you probably have a few seconds on the front of your video that has no sound track. I've seen this behavior when encoding movies to mp4.
Some of the videos have no audio for the first few seconds and the Roku goes into infinite buffering until you FFWD to a point where there is audio.

Hope this helps.

"RockyFord" wrote:
If you FFWD a minute or so into the video will it play?

If it does you probably have a few seconds on the front of your video that has no sound track. I've seen this behavior when encoding movies to mp4.
Some of the videos have no audio for the first few seconds and the Roku goes into infinite buffering until you FFWD to a point where there is audio.

Hope this helps.

You may be onto something there. Setting a PlayStart of 120 gets it through the buffering, and plays the audio, but still no video.

"RockyFord" wrote:
If you FFWD a minute or so into the video will it play?

If it does you probably have a few seconds on the front of your video that has no sound track. I've seen this behavior when encoding movies to mp4.
Some of the videos have no audio for the first few seconds and the Roku goes into infinite buffering until you FFWD to a point where there is audio.

Hope this helps.

Can you recommend any tools to analyze the wmv files to determine if the audio and video packets are interleaved properly?

It looks like the problem is in the video encoding, not the audio. The decoder is rejecting the video format. It's not immediately clear to me why, but I'll try to look into this next week.

--Mark