Latest post Fri, Jun 16 2017 10:53 PM by Vadym. 2 replies.
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  • Fri, May 19 2017 10:56 PM

    • JamesTV
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    Avid H264 Offline Codec - SD raster possible?


    After implementing JFIF 4:1s for our client - I wanted to explore what offline codecs were possible with Media Composer, and I have hit across what seems like an obvious oddity.

    At the very bottom end - using AMT you can produce a 0.8Mbps H264 proxy, or a 2Mbps H264 proxy. Stepping up from here, you get into JFIF 4:1s (approx 12Mbps), before then getting into DNxHD36 - obviously 36Mbps.

    It seems very odd that that the "HD Avid proxy" which is 2Mbps has a limitation of the same "half SD" raster as JFIF 4:1s - when clearly a 2Mbps H264 stream would be able to sustain at the very least a SD or even HD raster.

    Is there a reason for this when it comes to Media Composer? If we update the XML file within AMT to have a higher resolution - would this be supported by Avid?

    The concept being to find a codec that supports a SD raster for offline editing that sits between the chasm of 800kbps and 12Mbps.

  • Mon, May 22 2017 9:03 AM In reply to

    Re: Avid H264 Offline Codec - SD raster possible?

    I'd do some tests first. I've uesed the H264 codec on a job that required upload of proxy media from low bandwidth locations and it worked on for what we needed but I think its long GOP and you hit obstacles later on in the job depending on your workflow. It is also pretty poor compared to DNx36 and to be honest space is cheap nowadays but eyes not so.

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  • Fri, Jun 16 2017 10:53 PM In reply to

    • Vadym
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    Re: Avid H264 Offline Codec - SD raster possible?

    AMT XML is used to describe existing MediaComposer supported formats only. Changing it to some extent will work, but will not let you create a raster that doesn't exist in MC.

    If you're referring to the stored WxH of the H264 sample XMLs this gives you a real understanding of the internal stored picture. So even if you have full 1080p raster in DNx then transcode it into matching H264 the picture will be scaled down for it to store.

    MC will give you the full 1080 raster on the playback though by scaling it back up.

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