Cable Labs Changes OCUR Specification Expanding Copy-Freely Content – MythTV Users Rejoice

CableCARD is the technology that enables HTPC users to build the ultimate DVR. The kind of multi-tuner DVR backed by insane amounts of storage that makes it easy to “meh” when a company proudly proclaims the capabilities of their – not quite as spec’ful – aspirational kit. It has drawback though, especially if you prefer not to use Microsoft Windows Media Center (WMC), because while it is relatively easy to communicate with a Digital Cable Tuner (DCT) using UPnP and get the streams over RTP in applications like MythTV, NextPVR, or SageTV none of these provide support for the bane of CableCARD – DRM. Depending on your cable provider, this is either a huge problem (i.e. Time Warner/Cox) or not that bad (Comcast), at least until recently when the specification changed to allow the card to not provide a CCI flag (the digital indicator which notes Copy-Feely/Once/Never) on for content which should be marked Copy-Freely causing the DCT to fall back to CGMS-A, APS and RC (noted in Annex A above) which in most cases have random or incorrect values assigned. Requiring DRM on a show where it shouldn’t.

While Ceton wasn’t at CES, I did run into Eric Kotz while at the show and he mentioned that they were trying to get the OCUR specification changed to remove the need to monitor CGMS-A, APS, and RC so only CCI flags will be honored. That change was approved today (OCUR-N-14.1880-1) ; which means that everyone who was enjoying CableCARD content outside of WMC and started having trouble when the CCI flags went away are just a firmware update away from getting back to rocking out with their ultimate HTPC DVR.

With Ceton making the change request to Cable Labs I imagine the wait won’t be too long for their tuners, and I have reached out to SiliconDust for a comment. When I receive a response I will update the post.

Thanks Ceton!

Update 01/14/2015:

As richard1980 pointed out in the comments Ceton has released a pre-beta FW with this change. Eric also let me know that this problem/change also affects ClearQAM channels.

SiliconDust has posted a beta FW update.

  • Eric posted a link to

    Eric posted a link to pre-beta firmware here.

  • I’m a bit confused as to what

    I’m a bit confused as to what this actually means for us end users.  I thought we could already use cablecard tuners in various DVR front ends as long as the content was flagged as copy freely.  Can you break this down in layman’s terms?

    Do we need to upgrade the firmware even if we’re still using WMC?

    • There are different kinds of

      There are different kinds of content protection flags. The ones for CableCARD are called CCI. The CCI flag indicates if it is protected or not. When the CCI flag is missing the spec used to indicate that the DCT would fall back on the other flags (i.e. CGMS-A). The problem is that these other flags are wrong more often than not, which means that even though a show should be copy-freely it will get encrypted. This change means that the DCT only has to pay attention to the CCI flags (the right one), if the CCI is missing that is now interpreted as Copy-Freely.

      If you only use WMC to consume the recordings there isn’t a huge impact, unless you use comskip. So it’s probably best for WMC users to wait for non-beta FW, everyone else should update (I’ve heard several reports from SageDCT users that this has fixed their issues).

  • I use WMC, but still have

    I use WMC, but still have issues now and then.  This may help.  I scanned the Silicondust website, but so no reference of this. Will you update us when you get a response?

  • The link to the SD beta

    The link to the SD beta firmware is provided in the update to the article.