Forum Discussion

streamingguy's avatar
streamingguy
Visitor
14 years ago

MP4 or HLS for VOD?

Hello,

We have several movie DVDs, which we want to stream on ROKU as VOD. We tried with HLS, but got few issues.

1. Many encoders are not supporting encoding directly/importing source from DVDs.
2. All of our DVDs have few seconds of silence at the beginning. Due to this, all the encoders are not creating audio track. We tried with Digital Rapids, Sorenson Squeeze, Rhozet etc.,
3. Not able to find suitable encoder to use AC3/surround sound as audio output in HLS stream.
4. When we fast forward the stream, some times the video will stuck, but the audio will continue. After few seconds, both audio & video will sync and everything looks good. We do not have any audio only streams.

If I go with multiple bitrate MP4, we got several small DVD to MP4 software, which are accepting DVD source and without audio issue (#2).

Also, I can include AC3 audio in MP4 files.

So, is it good to use multiple bitrate MP4 files instead of HLS for VOD streaming?

I see only one disadvantage - If you want to provide streaming of certain part of a DVD, you need to re-encode only that particular part again (Just like a song/scene/chapter from DVD). In case of HLS, we can prepare a custom .m3u8 and play only that particular part.

If I use "StreamStartTimeOffset" / "PlayStart" options, will I get the above functionality with MP4?

Please let me know your suggestions and let me know if you find any good encoder which supports DVD import/HLS segmenting/without audio issues.

Thank you for your time!
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5 Replies

  • RokuMarkn's avatar
    RokuMarkn
    Visitor
    14 years ago
    Generally MP4 works fine for VOD content. HLS supports live streaming while MP4 doesn't. If you're not streaming live streams, MP4 should be fine. You can use PlayStart and PlayDuration to play a section of an MP4.

    --Mark
  • RokuMarkn's avatar
    RokuMarkn
    Visitor
    14 years ago
    1. I'm not sure if you can restrict trickplay to a section of the file. Most apps that use this feature disable FF/REW. It would probably be better if seeking were restricted to the range specified. I'll file an enhancement request for this.

    2. You don't have to do anything special, although remember that you can only seek to an I-frame. If you have certain critical seek points you should make sure that they each line up with an I-frame.

    3. There will be buffering between the segments. There's no way to avoid this other than to encode the content as one stream.

    --Mark
  • streamingguy's avatar
    streamingguy
    Visitor
    14 years ago
    Hello Mark,

    Thank you so much for your prompt reply. I will disable the trick play for time being. Also, thank you for considering this feature for enhancements list.

    Another question - Will "StreamStartTimeOffset" works fine, if I have DVR enabled on my streaming server? I am looking for time shifted streaming and enabling 3 hours of DVR on my streaming server.

    So, for EST users, the stream will be live. For PST users, I want to use "StreamStartTimeOffset" to set their starting point on the stream, which is EST - 3. I will be disabling trick play for this stream.

    Thank you
  • TheEndless's avatar
    TheEndless
    Channel Surfer
    14 years ago
    "RokuMarkn" wrote:
    ... Most apps that use this feature disable FF/REW ...

    How do you disable FF/REW on the roVideoScreen?
  • RokuMarkn's avatar
    RokuMarkn
    Visitor
    14 years ago
    "TheEndless" wrote:
    How do you disable FF/REW on the roVideoScreen?


    SetPreviewMode(true). The documentation could be clearer about this.

    --Mark