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  1. Member
    Join Date: Sep 2012
    Location: Australia
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    When I first began re-encoding my DVDs I muxed the end results into MP4s, unfortunately I found that when attempting to stream these MP4s via DLNA to my WDTV Live SMP when things got exciting the playback seemed to get stuck, stutter for a while and generally make the whole thing unwatchable. So I switched to MKV. Until recently I kept my old MP4s on one of my hard drives and I think I remember testing one of them on the last WDTV firmware and the problem was still there. I do remember encoding an episode of the Doctor Who - The Dominators in to an MKV and encountering the same problem (on a scene with a robot travelling through fog with the sound of the wind in the background (ie high bitrate)). Maybe I got that event confused with the idea of attempting to play back the old MP4s. Anyway, the WDTV just got a new firmware and I'm thinking maybe I should try reporting the issue, unfortunately, in the meantime, I've deleted all the old MP4s and the Doctor Who MKV. I've been trying to create a new MP4 to show the issue using a TV show I know caused it (Astro Boy) but of the three files I've made so far (Processed CRF14, Handbrake CRF 16, Non-filtered CRF13) none of them have managed to cause any problems at all. All I can think is that I either imagined testing the old files using the last firmware or the twin facts that MP4Box is adding a Max Bitrate element to the streams and Handbrake is setting the VBV bitrate to match the h264 level tips the WDTV off to exactly what's in the file. It could be that there was some other element in the old files that I can't recall.

    I was wondering if anyone else remembers this issue with Streaming to a WDTV and has a file they know triggers the problem that they'd be willing to share (or at least to post the MediaInfo/Bitrate Viewer output from).
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  2. Member
    Join Date: Sep 2007
    Location: Canada
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    Unlikely to be a bitrate or VBV buffer issue, since these are DVD sources (your bitrate range isn't going to close to a HD or BD source)

    I'm going to guess VFR ? common for videos encoded with old versions for handbrake where the CFR switch wasn't clear to see
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  3. Member
    Join Date: Oct 2004
    Location: Freedonia
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    I have a file that my first gen WDTV can't play correctly, but it probably wouldn't be of much use to you. I created it myself and the WDTV either plays it without audio or plays it without video - I don't remember which. I can tell you what I did, which you can easily re-create yourself.

    I took a Divx file of an old 1950s 3D film in anaglyph. The soundtrack was MP3 and not English. I used MMG from MKVToolnix to either open the Divx file directory or I demuxed it and opened the pieces. I don't remember which. Video was standard Divx/Xvid stuff. I added an English AC3 audio track to it and this had to be offset by some value to get it in sync with the video. The resulting MKV plays fine on a PC. None of my various standalone players can play it correctly. They either won't play it at all or only play the video or non-English audio. What I did is valid for MKV but unusual - there is no reason that an MKV file can't hold a Divx/Xvid video file, MP3 audio and AC3 audio.
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  4. Member
    Join Date: Sep 2012
    Location: Australia
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    Originally Posted by poisondeathray View Post
    Unlikely to be a bitrate or VBV buffer issue, since these are DVD sources (your bitrate range isn't going to close to a HD or BD source)

    I'm going to guess VFR ? common for videos encoded with old versions for handbrake where the CFR switch wasn't clear to see
    I'd turned off VFR very early on in my Handbrake phase and the fact that the files had far too low a bitrate to be causing bandwidth issues was entirely the point. The Dominators (or was it Krotons?) was processed with AVISynth and encoded at 50fps, and now that I think about it it's possible it was in an MP4 container too as I did both in the end.

    I guess it will have to remain a mystery.
    Last edited by ndjamena; 29th Aug 2014 at 18:29.
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  5. Member
    Join Date: Sep 2007
    Location: Canada
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    Originally Posted by ndjamena View Post
    Originally Posted by poisondeathray View Post
    Unlikely to be a bitrate or VBV buffer issue, since these are DVD sources (your bitrate range isn't going to close to a HD or BD source)

    I'm going to guess VFR ? common for videos encoded with old versions for handbrake where the CFR switch wasn't clear to see
    I'd turned off VBR very early on in my Handbrake phase and the fact that the files had far too low a bitrate to be causing bandwidth issues was entirely the point. The Dominators (or was it Krotons?) was processed with AVISynth and encoded at 50fps, and now that I think about it it's possible it was in an MP4 container too as I did both in the end.

    I guess it will have to remain a mystery.

    Turned off VBR or VFR ?

    If you used avisynth, then you probably didn't use handbrake for those, since it's not supported. And if you used avisynth, it will produce CFR output , unless you specifically used timecodes with the purpose of generating VFR

    It's easy to trip up completely (as in not play) with something like 10bit encoding, 422 etc...but I thought you had handbrake in mind
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  6. Member
    Join Date: Sep 2012
    Location: Australia
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    Astro Boy was an old Handbrake encode, Doctor Who was AVISynth/X264, there was a rather large time gap in between. Turning 'VFR' off was one of the first things I did while using handbrake.

    I'm trying to remember what I was doing, I have this nasty feeling I tried re-encoding a Blu Ray of Transformers: The Movie to test if bitrate was the problem but got so engrossed with trying to figure out how to process a Blu Ray and finding the right filters that I forgot why I was doing it in the first place. That would explain why I can't remember anything and why I have a 720p MP4 rip of Transformers in my iphone folder, but it's not really useful information.
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  7. Originally Posted by ndjamena View Post
    Turning 'VFR' off was one of the first things I did while using handbrake.
    Even if you turn off VFR in Handbrake the MP4 files it output were marked VFR. At least MediaInfo reported them as VFR. That was a longstanding bug in Handbrake. CFR MKV works properly.

    One recent discussion about the issue:
    http://forum.videohelp.com/threads/358247-Alternative-to-Handbrake-for-x264-video-enco...dbrake+vfr+cfr

    I have lots of sample videos that trip the the WDTV Live. But most of them are HD. The few SD videos that cause problems mostly use unsupported codecs or are corrupt.
    Last edited by jagabo; 29th Aug 2014 at 19:01.
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  8. Member
    Join Date: Sep 2012
    Location: Australia
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    Assuming MP4Box doesn't update the flag in the stream header when it finds all time-codes are consistent with CFR it's possible I fed a UT VC intermediate AVI to x264 directly which got the .264 elementary stream flagged as VFR... Still, the symptoms would seem to be a tad excessive. Corruption is a possibility, VLC could play them fine but maybe it just has better redundancies.

    Astro Boy was so long ago I don't remember what I did to diagnose it, I can't believe I wouldn't have tried to play it from a usb flash drive but I don't really remember all that much.
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