Is Comcast DVR box OK for HDTV?

Question

I am getting an HDTV. Called Comcast, and they said that the DVR cable box I have now is OK for HD. Is this true? Will this box provide the best HD?

Answer 1

I have the comcast DVR box DCT6412.  It is a DVR box for HD and works fine.

You have to make sure though that the box can be set for 720p or 1080i.  In my case, I have to press the menu button when the comcast box is turned off.  A new hidden menu comes up where the output format (480i, 720p, or 1080i) can be selected.

To get high def, set it to 720p or 1080i.  Also, high def can only be carried by Component or HDMI cables.  Get rid of the old composite or S-Video or even coax between the box and tv - those won't work for you.

Don't always trust comcast reps.  They sometimes don't know what they are talking about.  I've asked them questions before and got incorrect answers.  One guy told me a box was doing 720p at 30 frames per second, but when I looked at the specs it was 60 frames per second just like HD broadcast is supposed to be and my TV is showing 60 frames per second when I press its display button.

By the way, the best HD is not from the cable box or satellite box.  Better than that is off the air broadcast if you can receive it for local stations.  And even better than that is from a HD DVD player like blu-ray.  It can output 1080p.  Broadcast only goes up to 1080i.  Anyway, you haven't seen anything yet.  Better even than the HD DVD is what the studio has.  You get a compressed version of video (even on blu-ray) and the compression rate between broadcast and what comes off the camera is like a factor of 150.

The standard FCC allotment for digital off-the-air broadcasts is 20 million bits per second per digital hd station (20 Mbps).  What comes off of the camera is something like 1-3 billion bits per second (1.5 Gbps).  You have 1920x1080 pixels 30 times per second with 12 bits for luminence/intensity per pixel and another 12 each for blue and red per pixel (green is a difference between the intensity and blue and red).  Your TV can handle the high 1.5 or 3 Gbps, but you never see more than 40Mbps=20x2 (QAM) from the 20 Mbps off-the-air broadacast  or the 8-12Mbps that the cable company gives you with even more compression (they might give you as much as the off-the-air broadcast sometimes, but they like to compress things).  If you saw the full 1.5 or 3 Gbps, it'd blow your mind.

The compression sends the full picture only sometimes and the partial images based on what changes in between with some made up / predicted frames.  Worse yet, the color is averaged for blocks of pixels.  It's much better than the standard traditional broadcast and we need to make that compromise to transmit so much information, but wow what'd it be like to see the original content.

Answer 2

If it has component and HDMI outputs-yes it is.