Directv compression on HD Channels

[Lem52]

I have really noticed a big change in the way the picture looks on Channels 73-83. Last week these were more clear and vivid. Well, they sure look fuzzy right now. Anyone else seeing what I see?

I think Directv keeps putting on the compression. If this keeps up, I think I will drop them and just wait until things get better. Ain't no use paying to get HD from Directv and end up getting the shaft with poor quality crap like they are doing right now.

Lem52

 

[matthpd195]

Actually right now you shouldn't be paying for the HD Pack.....as it's free for 6/months.

 

[charper1]

mine look great.

 

[matthpd195]

I would agree with charper1, they have been looking a lot better recently.

 

[Lem52]

But if I cancel my present package of HD, I would have to recommit to a year wouldn't I?

I am just 5 months into my commitment and don't want to screw that up if I can help it, however, if I keep seeing the picture getting fuzzier and fuzzier, especially on the channels that are supposed to be HD, I am going to bale out and take the prorated charge of whatever they decide to charge me.

Lem52

 

[Lem52]

I would agree with charper1, they have been looking a lot better recently.

If the program is hd it is ok, but I am noticing more compression on those channels when they are not running HD programs. I think they just turned up the compression on those in the last 2 or 3 days.

Lem52

 

[fkostyn]

Well, hopefully this will all be fixed next may when the new Sat's are up... If not my 1yr on my new HD box is up..... and I'll go with someone else.

 

[zubinh]

For the most part I've been very happy with D* HD. There are times when Showtime HD looks fuzzy especially on Sundays, but the other channels are just fine. IMHO, HDNet always has the best PQ. Like looking thru a window

 

[Bowtieman]

I have really noticed a big change in the way the picture looks on Channels 73-83. Last week these were more clear and vivid. Well, they sure look fuzzy right now. Anyone else seeing what I see?

I think Directv keeps putting on the compression. If this keeps up, I think I will drop them and just wait until things get better. Ain't no use paying to get HD from Directv and end up getting the shaft with poor quality crap like they are doing right now.

Lem52

Here is a site that gives up to date bitrates for all direct hd channels.

http://www.widemovies.com/dfwbitrate.html

 

[Chris Gerhard]

The three movie channels HBO, Showtime HD, and HDNet Movies are all crammed on the same transponder now and are not truly HD by any stretch of the imagination. Hopefully after the NFL season is over, DirecTV will no longer have to do that. As the above referenced link indicates all are indicated as red, meaning the bitrate is too low. My personal preference would be give those premium channels greater bandwidth until NFL Sunday ticket is over and let HDNet and DiscoveryHD suffer but DirecTV did not do that for some reason. Picture quality on those channels is generally no better than DVD quality at the bitrate used but it can vary. This has been going on since the NFL season started.

Chris

 

[charper1]

As for HDNet and HDNet Movies, I have read they are bound by contract NOT to.

 

[Darin]

My personal preference would be give those premium channels greater bandwidth until NFL Sunday ticket is over and let HDNet and DiscoveryHD suffer but DirecTV did not do that for some reason.

My guess would be that the movie channels are currently given less bandwidth because they don't need as much bandwidth. Since the movie channels are typically showing transfers from film, the content doesn't have as much resolution, due to limitations in the telecine process. They are also typically 24fps material, which can consume less bandwidth assuming the repeat flags are proprerly used. HDNet and DiscoveryHD, OTOH, typically show content generated from HD video cameras, which is 30fps, and can contain more resolution than typical telecined film, and therefore would suffer much more from the same amount of bandwidth limiting.

 

[Bear]

My guess would be that the movie channels are currently given less bandwidth because they don't need as much bandwidth. Since the movie channels are typically showing transfers from film, the content doesn't have as much resolution, due to limitations in the telecine process.[..]

huh? Telecine is a way of alternating fields to convert 24fps into 30fps by interposing frames together in a prescribed fashion. While some TC equipment might lose resolution, that should not be obvious in studio-quality equipment. As for resolution differences, a single 35mm frame of film stock is around 4kx4k pixels (I'm giving a very rough approximation here - Google will tell you the exact res...). No HD cam currently comes close to this.

 

[colofan]

Is that 4k X 4k pixels where each pixel represents the complete gamut of color and contrast?

 

[Darin]

huh? Telecine is a way of alternating fields to convert 24fps into 30fps by interposing frames together in a prescribed fashion.

No, telecine is the process to get film transferred to video. PART of that process typically includes frame rate conversion, but that's not the ONLY aspect of the telecine process. I think it's often assumed to only relate to the 24 to 30fps conversion because INVERSE telecine typically only addresses going back from 30fps to 24fps, not all the way back to film (of course). This may help. And while it's true that film has much more resolvable resolution than the current HD standard, today's telecine equipment generally results in video with much less RESOLVABLE resolution than what HD video can contain if fed a better signal. Most sources I've seen suggest that HD video sourced from a film transfer can only resolve detail that would correspond to a horizontal resolution of 800-1400. There is some interesting discussion of it here. Most video sources are a little higher than that, at 1400+, depending on the format. But still, most of what we see is below the 1920 lines of the 1080x1920 standard.

 

[Bear]

Darin - With all due respect to Stacy and Joe Kane, they were talking about post-scan images if I read that right (I only read a bit). Try "BarkingArt's" post here:

http://www.avsforum.com/avs-vb/showthread.php?postid=4064498#post4064498

He's "in the business", and says that 4k is full resolution, and he even included a link to an order form at a scanning shop to rub my face in it!

Later,
Bill

 

[Darin]

To be honest, I'm not quite sure what the point is. Whether the scan was done at 2k or 4k, it ultimately has to end up at 1920x1080 (discounting 720). I believe 4k IS considered "full resolution", simply because that's often considered to be what is required to capture film down to the grain level. But that doesn't mean that that's what is typically used to scan to HD. There's some reading on that at http://www.cinematography.net/Pages DW/QuantelGuideToDI.htm.

Even if they are scanned at 4k, that still doesn't mean that the end result, once converted into a 1920x1080 HD stream is going to have RESOLVEABLE resolution equal to the physical resolution of HD. If you take a look at the digital camera reviews over at dpreview.com, you can see that the resolution charts aren't reproduced to the full resolution of the camera's native resolution. The CCDs used don't actually produce full color data at the specified resolution: bayer pattern interpolation is used to get to the final resolution. Optics and image processing algorithms also play a role. Film scanners are also subject to these influences, and the final interpolution to HD resolution can be an added step.

I can't offer any first hand experience in the subject, but I can say that I've read from several sources that HD film transfers typically resolve at well under the technical HD resolution spec.

 

[hdtvtechno]

So i heard that they gave HDNET only bitrate of 8

 

[Darin]

HDNet Movies, not HDNet. The movie channels don't tend to need as much bandwidth as the video channels.