# DirecTV MPEG-4 Bitrate/Resolution



## charlie460 (Sep 12, 2009)

Is there any current information as to what bitrates DirecTV broadcasts? Do they still downres to 1440 or 1280x1080 or have they gone back to full-resolution 1920x1080 since the switch to MPEG-4 long ago?

I can't find any information regarding bitrates/resolution since the MPEG-4 transition a long time ago.


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## The Scotsman (Sep 1, 2007)

charlie460 said:


> Is there any current information as to what bitrates DirecTV broadcasts? Do they still downres to 1440 or 1280x1080 or have they gone back to full-resolution 1920x1080 since the switch to MPEG-4 long ago?
> 
> I can't find any information regarding bitrates/resolution since the MPEG-4 transition a long time ago.


Hi Charlie
Let me be the first to voice my support to your question. A few years back, there were posts referring to HD Lite. Whenever there was any discussion about this in the AV forums, tempers flared and many members pointed out that resolution is less important than overall bit rate. I tried to put in my tuppence worth by emphasizing that the true HD rez is 1920 x 1080, so any broadcasting of 1280 x 1080 or 1440 x 1080 would not be the real McCoy. I believe there are still 16:9 plasma panels on sale here and there with 1024 x 768 and those who buy them will never care about what is broadcast. I'm a stickler for true 1920 x 1080, but I don't know of a way to verify. Not forgetting of course that there are many native 720p channels and they will be broadcast at 1280 x 720. I will be reading this thread with interest.


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## LameLefty (Sep 29, 2006)

The Forum search function is your friend. This has been beaten to death over the years.


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## veryoldschool (Dec 10, 2006)

LameLefty said:


> The Forum search function is your friend. This has been beaten to death over the years.


"yep", but to the OP: 
All DirecTV HD is "full resolution". The move to MPEG-4 allowed this and bit rates can be monitored by using DirecTV2PC.


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## CCarncross (Jul 19, 2005)

Why is this important? You either like the PQ you get, or you go with someone else. This numbers game became tiresome about a day after it got beat to death.


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## veryoldschool (Dec 10, 2006)

Maybe it's just me, but why not answer a member's post [if we can] and skip the "attitude"?


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## The Scotsman (Sep 1, 2007)

veryoldschool said:


> Maybe it's just me, but why not answer a member's post [if we can] and skip the "attitude"?


I'm with you, VOS.


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## P Smith (Jul 25, 2002)

Find my recent posts - there is bandwidth of MPEG-4 [Ka] channels; those are 1920x1080i.


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## charlie460 (Sep 12, 2009)

Sorry, didn't mean to instigate anything here... I was just curious. I searched a bit and didn't find any recent (most posts were years old) information on bitrates/resolution in use by DirecTV now. 

It's merely out of curiosity -- I'm satisfied with DirecTV's PQ, but I'd like to know the details as well.


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## charlie460 (Sep 12, 2009)

P Smith said:


> Find my recent posts - there is bandwidth of MPEG-4 [Ka] channels; those are 1920x1080i.


I went through about 8 pages of your post history and didn't see anything regarding D* bw, would you mind pointing me in the right direction? Appreciate it!


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## veryoldschool (Dec 10, 2006)

charlie460 said:


> Sorry, didn't mean to instigate anything here... I was just curious. I searched a bit and didn't find any recent (most posts were years old) information on bitrates/resolution in use by DirecTV now.
> 
> It's merely out of curiosity -- I'm satisfied with DirecTV's PQ, but I'd like to know the details as well.


I hope you've gotten some of what you wanted.
Bit-rates with MPEG-4 don't really relate to MPEG-2.
This morning I compared Hawaii 5 0 OTA & DirecTV.
OTA was 15-19 Mb/s, while DirecTV would peak at 16Mb/s, but also dropped as low as 6 Mb/s.


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## charlie460 (Sep 12, 2009)

veryoldschool said:


> I hope you've gotten some of what you wanted.
> Bit-rates with MPEG-4 don't really relate to MPEG-2.
> This morning I compared Hawaii 5 0 OTA & DirecTV.
> OTA was 15-19 Mb/s, while DirecTV would peak at 16Mb/s, but also dropped as low as 6 Mb/s.


I know it's not the same as MPEG-2 (as MPEG-4 is far more efficient than MPEG-2). How are you measuring these rates? DirecTV2pc + network monitoring?

Also, is it possible to dump the transport stream from DirecTV in any way? (I assume not, I can't find anything about doing it since the MPEG-4 transition)


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## veryoldschool (Dec 10, 2006)

charlie460 said:


> I know it's not the same as MPEG-2 (as MPEG-4 is far more efficient than MPEG-2). How are you measuring these rates? *DirecTV2pc + network monitoring*?
> 
> Also, is it possible to dump the transport stream from DirecTV in any way? (I assume not, I can't find anything about doing it since the MPEG-4 transition)


Yes.

As for what the resolution is, there was "a hole" several years back, for a short time, which allowed some apps to read the recordings. During this time, someone was able to read the header info, which gave the resolution. You won't be able to do this anymore as "the hole" was plugged shortly after we found it. :lol:


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## P Smith (Jul 25, 2002)

charlie460 said:


> I went through about 8 pages of your post history and didn't see anything regarding D* bw, would you mind pointing me in the right direction? Appreciate it!


I did; there, an example http://www.dbstalk.com/showpost.php?p=2738926&postcount=114


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## Diana C (Mar 30, 2007)

veryoldschool said:


> Maybe it's just me, but why not answer a member's post [if we can] and skip the "attitude"?


I don't think it is a case of "attitude" but rather just a natural dread of another fire fight over the issue.

The reality is that resolution and bit rates are like all statistics...they can prove whatever you want them to prove. Since *ALL* video compression algorithms in use today are lossy (ie. the decompressed picture contains less detail or resolution than the original) the numbers don't give a real indication of quality. I can compress a 1920x1080 stream down to 500kbps, and then decompress it back to 1920x1080. It will just be blobs of colors, but it will be "full HD resolution" blobs. 

The only thing that can be said is that, all things being equal, the higher the allocated bit rate, the better. (of course, all things are rarely equal)

Also, keep in mind that DirecTv gets the streams already compressed. An uncompressed 1080p stream would be almost 180 *giga*bits per second. Compared to the MPEG-2 compression that takes it down to the 12 to 18 megabits/second that the channels transmit, the additional MPEG-4 compression DirecTV does to bring it down to 6 to 12 megabits/sec is pretty minor.


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## veryoldschool (Dec 10, 2006)

Titan25 said:


> Also, keep in mind that DirecTv gets the streams already compressed. An uncompressed 1080p stream would be almost 180 *giga*bits per second. Compared to the MPEG-2 compression that takes it down to the 12 to 18 megabits/second that the channels transmit, the additional MPEG-4 compression DirecTV does to bring it down to 6 to 12 megabits/sec is pretty minor.


I think it's reasonable to compare to ATSC MPEG-2 bit-rates, though of course MPEG-4 will, by its nature, be less.


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## Diana C (Mar 30, 2007)

veryoldschool said:


> I think it's reasonable to compare to ATSC MPEG-2 bit-rates, though of course MPEG-4 will, by its nature, be less.


Since, as you say, the MPEG-4 bit rate will be less than the ATSC MPEG-2 rate, what are we comparing? Most folks don't have the ability to do side by side comparisons of OTA and DirecTV versions of the same content. It all boils down to subjective opinion - if you think it looks good, it IS good. If not, look for another provider that will meet your needs.


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## charlie460 (Sep 12, 2009)

I think the only provider that will provide consistently better quality than DirecTV is FiOS, which generally passes along the MPEG-2 feed they receive from the broadcaster directly.

U-Verse looks horrible at about 6 Mb/s MPEG-4, and Comcast recompresses many channels down to 10-12 Mbps MPEG-2 here, which is not great either.


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## veryoldschool (Dec 10, 2006)

charlie460 said:


> I think the only provider that will provide consistently better quality than DirecTV is FiOS...


I might even question this. 
For this to have merit, MPEG-4 would need to be inherently inferior to MPEG-2.


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## veryoldschool (Dec 10, 2006)

Titan25 said:


> An uncompressed 1080p stream would be almost 180 *giga*bits per second.


Not sure where you got this as HDMI (1.3) has a maximum bit-rate of 10.2 Gbit/s (340 MHz)


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## LameLefty (Sep 29, 2006)

veryoldschool said:


> Not sure where you got this as HDMI (1.3) has a maximum bit-rate of 10.2 Gbit/s (340 MHz)


I'm pretty sure he's talking network HD backbone feeds or something like that, nothing accessible to or used by consumer equipment.


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## veryoldschool (Dec 10, 2006)

LameLefty said:


> I'm pretty sure he's talking network HD backbone feeds or something like that, nothing accessible to or used by consumer equipment.


I don't think it even comes out of their cameras at that and from what I've heard of "their backbone", it's in the 40-80 Mb/s range.


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## HoTat2 (Nov 16, 2005)

LameLefty said:


> I'm pretty sure he's talking network HD backbone feeds or something like that, nothing accessible to or used by consumer equipment.





veryoldschool said:


> I don't think it even comes out of their cameras at that and from what I've heard of "their backbone", it's in the 40-80 Mb/s range.


AFAIK, the fastest bit rates for HD production in the broadcast industry are in the 3 gigabit range for 1080p60.

Sometimes called "3G-SDI" format for 3 gigabit HD-SDI.


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## P Smith (Jul 25, 2002)

veryoldschool said:


> I don't think it even comes out of their cameras at that and from what I've heard of "their backbone", it's in the 40-80 Mb/s range.


I would quote SMPTE 424M: "3G-SDI, consisting of a single 2.970 Gbit/s serial link".


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## charlie460 (Sep 12, 2009)

veryoldschool said:


> I might even question this.
> For this to have merit, MPEG-4 would need to be inherently inferior to MPEG-2.


Well, FiOS passes along the MPEG-2 feed they're provided, DirecTV has at least one step of re-compression from the provider's MPEG-2 feed into their MPEG-4.


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## Jeremy W (Jun 19, 2006)

veryoldschool said:


> This morning I compared Hawaii 5 0 OTA & DirecTV.
> OTA was 15-19 Mb/s, while DirecTV would peak at 16Mb/s, but also dropped as low as 6 Mb/s.


I don't think monitoring bitrates using DirecTV2PC is very reliable. I can't imagine the statmux allowing any channel to hit 16 Mbps. It's just not necessary.


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## Steve (Aug 22, 2006)

Jeremy W said:


> I don't think monitoring bitrates using DirecTV2PC is very reliable. I can't imagine the statmux allowing any channel to hit 16 Mbps. It's just not necessary.


According to Rabbit Ears, WCBS-DT here in NY broadcasts up to 17.5 Mbps. :shrug:


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## Jeremy W (Jun 19, 2006)

Steve said:


> According to Rabbit Ears, CBS here in NY broadcasts up to 17.5 Mbps.


That's OTA. I was referring to DirecTV MPEG4.


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## Diana C (Mar 30, 2007)

"veryoldschool" said:


> Not sure where you got this as HDMI (1.3) has a maximum bit-rate of 10.2 Gbit/s (340 MHz)


Went back and checked my math and I did multiply by 60 twice. My mistake, 3Gbits/second is correct.


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## Diana C (Mar 30, 2007)

"LameLefty" said:


> I'm pretty sure *he's* talking network HD backbone feeds or something like that, nothing accessible to or used by consumer equipment.


I'm a she.


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## HoTat2 (Nov 16, 2005)

Jeremy W said:


> I don't think monitoring bitrates using DirecTV2PC is very reliable. I can't imagine the statmux allowing any channel to hit 16 Mbps. It's just not necessary.


But if IRD-DVRs indeed function essentially as "bit-buckets" streaming data onto a HDD in the same form and rate its received from the provider, then where would the additional increase in bit rate noted in the stream to the DIRECTV2PC app be coming from if not natively the bit rate of the file originally recorded?


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## Jeremy W (Jun 19, 2006)

HoTat2 said:


> But if IRD-DVRs indeed function essentially as "bit-buckets" streaming data onto a HDD in the same form and rate its received from the provider, then where would the additional increase in bit rate noted in the stream to the DIRECTV2PC app be coming from if not natively the bit rate of file originally recorded?


I'm assuming VOS was watching the overall bitrate on his NIC, not DirecTV2PC specifically. So it could have been anything.


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## P Smith (Jul 25, 2002)

Steve said:


> According to Rabbit Ears, WCBS-DT here in NY broadcasts up to 17.5 Mbps. :shrug:


I did provide link back when real downlink mux monitored to answer to particular question about one channel's bandwidth.


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## veryoldschool (Dec 10, 2006)

Jeremy W said:


> I'm assuming VOS was watching the overall bitrate on his NIC, not DirecTV2PC specifically. So it could have been anything.


1) try it yourself
2) when DirecTV2PC is the only process running, it should be "fairly accurate"


> I can't imagine the statmux allowing any channel to hit 16 Mbps. It's just not necessary.


Don't imagine, run it and see. I've seen [on a very rare case] over 20 Mb/s consistently, which also matched the disk usage of the same programs [Ken Burns' National Parks series].


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## Jeremy W (Jun 19, 2006)

veryoldschool said:


> 1) try it yourself
> 2) when DirecTV2PC is the only process running, it should be "fairly accurate"


I have done this, and I've seen spikes like you. Unless you're going crazy and shutting down everything on your PC, there are tons of background processes that can start up and download stuff without any indication. It's just not a terribly accurate method of measurement.


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## veryoldschool (Dec 10, 2006)

Jeremy W said:


> I have done this, and I've seen spikes like you. Unless you're going crazy and shutting down everything on your PC, there are tons of background processes that can start up and download stuff without any indication. * It's just not a terribly accurate method of measurement.*


While there are more accurate methods, this isn't as far off as you seem to assume [or are you just being "a Jeremy" here?].


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## Jeremy W (Jun 19, 2006)

veryoldschool said:


> While there are more accurate methods, this isn't as far off as you seem to assume [or are you just being "a Jeremy" here?].


You weren't watching the overall bitrate of your NIC, so what I said doesn't even apply.


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## veryoldschool (Dec 10, 2006)

Jeremy W said:


> You weren't watching the overall bitrate of your NIC, so what I said doesn't even apply.


Jeremy, quit being "a Jeremy". You don't know what I was or wasn't watching, and what "I have watched", matches fairly closely the disk usage.


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## skatingrocker17 (Jun 24, 2010)

I have a capture card that allows has 1 composite input, 1 component and 1 HDMI. I can record HD over HDMI as long as there's no protection. BUT, I wonder if I can use the HDMI input to measure the bandwidth of a DirecTV signal.


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## veryoldschool (Dec 10, 2006)

skatingrocker17 said:


> I wonder if I can use the HDMI input to measure the bandwidth of a DirecTV signal.


"If you could", it would be the uncompressed signal. which may be around 1.3 Gb/s and not of much use here.


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## P Smith (Jul 25, 2002)

It could be measure by monitoring mux (by known PIDs for particular channel), but it would give you more fuel to the disputing:
*Each channel, each program has different bitrate at each minute or so of transmission*.


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## Jeremy W (Jun 19, 2006)

veryoldschool said:


> Jeremy, quit being "a Jeremy". You don't know what I was or wasn't watching, and what "I have watched", matches fairly closely the disk usage.


I was admitting that I was wrong, and that you were right. Stop trying to make me the bad guy and read what I'm saying.


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