Resolution and bitrate chart

John Kotches said:
... Bitrates not so much as they can vary wildly based on content...
Agreed, but isn't a bit-starved signal a major contributor to poor PQ in terms of "blockiness" and skipped frames, etc...?
 
bhelms said:
Agreed, but isn't a bit-starved signal a major contributor to poor PQ in terms of "blockiness" and skipped frames, etc...?

It can be, but it is not always.

A drama, like The West Wing for example wouldn't need as much bit rate as Smallville or one of the CSIs would. An extreme example to be sure, but you see my point.

The ABR (Average Bit Rate) could be an indicator of PQ, and it could be an indicator that the show doesn't need much in the way of a bit rate.

You can't even say that the higher the ABR, the less likely you are to have artifacting you'll have as you then have less bandwidth left over for peaks.

Cheers,
 
Which CSI? Or are they all similar in terms of bitrate requirements? I would have thought the original, and to a lesser extent NYC would *need* less bitrate than Miami in order to look great.

Sorry that was a bit OT, good points though overall on the bitrate vs. resolution thing. :)
 
Bitrate is more important than Resolution in everything that I have read.
As long as the Resolution is in the ballpark, and the Bitrate is high, you will have a great picture. The opposite can't be said.
 
John Kotches said:
...You can't even say that the higher the ABR, the less likely you are to have artifacting you'll have as you then have less bandwidth left over for peaks...
Tks, John - I guess this is analagous to having a 250-watt amp for "quiet" audio just to have enough reserve for the peaks without distortion. I see what you're saying...

However, I also understood it like dslate69 states it...
 
dslate69 said:
Bitrate is more important than Resolution in everything that I have read.
As long as the Resolution is in the ballpark, and the Bitrate is high, you will have a great picture. The opposite can't be said.

It is not an absolute...

Plus, with MPEG-4 encoding, a lower Bitrate can look better than a higher bit rate than MPEG-2.

It also has to do with how much motion and how much change there is between fully rendered frames.

It is not as simple as X has a higher bitrate and therefore will look better than Y at a lower bit rate.

Regards,
 
Kirby Baker said:
Which CSI? Or are they all similar in terms of bitrate requirements? I would have thought the original, and to a lesser extent NYC would *need* less bitrate than Miami in order to look great.

Sorry that was a bit OT, good points though overall on the bitrate vs. resolution thing. :)

They all have their moments...

When you dial up the detail meters, and they all have lots o' detail, you dial up your bit rate requirements.

Fast motion requires the most though.

Cheers,
 
bhelms said:
Tks, John - I guess this is analagous to having a 250-watt amp for "quiet" audio just to have enough reserve for the peaks without distortion. I see what you're saying...

However, I also understood it like dslate69 states it...

It's a balancing act. You need to be high enough not to artifact while still allowing yourself enough left over (aka headroom) for peaks to prevent them from developing artifacts.

It's never simple unfortunately.

Edited to correct a wording error

Regards,
 
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Let's keep in mind that raw, uncompressed HD video comes out at a whopping 1.65 Gbits / second, and we are talking about "throwing away" ~99% of the data. 1,650 Mbits /second * .01 = 16.5 Mbits/second. Maximum bit rate is about 20 Mbits/second for Broadcast HDTV.

Regards,
 
If there are no current sites charting the E* HD channels, does anyone know what is being broadcast in HD-Lite? Is it just the Voom channels and HDNet Movies?
 
Scott Greczkowski said:
Maybe Digiblur can make one for us. :)

I'll run some bit rates charts if someone can post the updates to a web page. I can't see the resolutions since the streams are encrypted. Whoever has one of those modified receivers that can record the streams they sub to can see the resolutions.
 
HDNet and HDNet Movies are at 1440x1080i right now, with HDNet Movies having about 2 more mb/s than HDNet, their bitrates are floating all over the place (but the pattern is HDNet Movies gets a bit more...) (HDNet Movies is around 15.5, HDNet 13.5 ...

And NFL HD Preview is at 1440x1080i, and its bitrate is abysmal (8.21 mb/s)

... I'd like to see it at 0 and see HDNet & HDNet Movies go back to 17.6 mb/s with 1920x1080i...
 

Closed captioning in HDNET 9422

Dish still replacing 811's with 811's

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