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USA HD: Picture Sucks

I’m not sure exactly what is causing this, but the picture on USA HD absolutely sucks. Even with shows like Monk or House, with little to no action sequences, there’s severe macro-blocking, artifacts, video/audio corruption, audio cutouts, and frame-dropping. This really seems like crappy/overloaded hardware to me (or possibly a bandwidth issue), rather than a re-compression problem. Normally if there’s a re-compression/compression issue, you will notice macro blocking, but not audio/video cutouts or corruption.

Here’s some examples from the movie Final Destination 2 (scaled to ~1/3 the actual size).

In this first frame, it just looks like macro-blocking.

Final Destination 2: Frame 1

However, in the following frames, there’s clearly corruption going on. Also, note that the audio cut out for about a second shortly after this part.

Final Destination 2: Frame 2

Final Destination 2: Frame 3

Some possibilities are:

  1. The hardware Comcast is using for USA and Sci-Fi is either overloaded, or really crappy. I’ve heard Comcast has been using Imagine Communication hardware to triple-load three channels on to a single QAM frequency, and there’s been some issues with that setup.
  2. USA’s encoding hardware is really crappy. That would make sense, since both USA and Sci-Fi are owned by the same company, and both have horrible picture.

This entry was posted on Monday, April 7th, 2008 at 9:44 am and is filed under HDTV, Comcast. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

2 Responses to “USA HD: Picture Sucks”

  1. Ian Eure Says:
    April 7th, 2008 at 3:07 pm

    http://digg.com/television/Comcast_Degrades_HD_Quality_To_Make_Room_For_More_Channels

    It does look like you’re losing some bits. I see that the quality you’re getting is in line with the captures that guy posted. He also mentions that there are dropped frames.

    I don’t know how you’re capturing, but there’s also the (slight) possibility that you have an issue with your decoder.

  2. admin Says:
    April 7th, 2008 at 3:37 pm

    I’m absolutely loosing bits. I was just trying to watch something on USA HD, and it was unbearable. At one point, nearly half the screen was missing blocks or macro-blocking, and audio cut out for several seconds.

    FYI, I’m capturing the raw MPEG-2 transport stream via firewire, and I don’t have any issues capturing from any other channels. The same thing happens on my TV, so it’s not the video cap.

    If you want to get into the raw details, what Comcast is doing is re-compressing video to average bitrate, so they can squeeze three 17-19 mbps streams on to a single 40mbps QAM frequency.

    Also, USA HD and Sci-Fi HD are the only channels that I’m having this problem with.

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