HD resolution and bitrate

As a DISH Network subscriber, I occasionally read and post on a forum for DISH users.  It helps me stay up to date on new channels, new features, promotions, and problems. 

Recently, I was reading a thread in which another user was questioning the 1440x1080i resolution of many HD channels on DISH, wondering why they weren’t being broadcast at 1920x1080i.  He was wondering about how this affects HD picture quality.  As with most internet forums, there was some good information in the thread, and there was some not-so-good information in the thread.  I decided to weigh in myself, and this was my response.

To me, bitrate is more important than resolution.  For instance, I would rather watch a high bitrate 480p source like a DVD on my 1080p TV than a 1080p video on youtube that has been mangled by compression to reduce the bitrate enough to stream it over the internet.  I know it’s an extreme example, but it should still serve to make my point.  We’re dealing with lossy compression formats here.  There is no way around that.

The difference in picture quality between 1440x1080i and 1920x1080i isn’t all that much, and at the exact same bitrate 1440×1080 could actually serve to produce a slightly better image with less compression artifacting (depending on a number of variables in the compression process).  In fact, the macroblocks tend to make the exact resolution of the display irrelevant since they are larger than the individual pixels.  Remember… lossy compression!

It can be confusing because so much of the sales and marketing focuses on the resolution and refresh rate of the displays and the content.  What gets left out is the fact that all video content that we consume is compressed with lossy compression techniques (even blu-ray disks).  Why do blu-ray disks look so good?  bitrate!  They’re anywhere from 2-5 times the bitrate of what you get from your TV provider.  Hi bitrate 1080p video?  Beauty!

It is also important to note Dish doesn’t give every channel the same amount of bandwidth on their system.  Some channels are delivered to us at higher bitrates than others.  This variation from channel to channel makes a difference.  ESPN’s 720p signal looks much better than many of the 1080i channels out there due to the fact that it is transmitted at a higher bitrate.  I remember looking at a chart of bitrates for each HD channel on DISH a few months ago, but I can’t find it now.  If I can locate it, I’ll edit this post with a link.

I’ve found that how the TV is calibrated makes a huge difference in picture quality from any source.  If you haven’t taken the time to calibrate your TV, you should!  I don’t mean by just adjusting the sliders until it “looks right”.  I mean, by actually calibrating it with the right tools.  At the very least, get a disk with the calibration patterns and the blue filter glasses (to adjust color) and tweak your TV.  You’ll probably be amazed at how far off of optimal your settings are.

So, in short… it isn’t nearly as clear cut as we would like it to be.  Don’t get too hung up on the exact resolution of the video source.  Due to a number of factors, picture quality from each resolution, 1920×1080, 1440×1080, or 1280×720, could look better or worse than the other two.

Make sure your TV is calibrated, and enjoy the content!