Hauppuage HD PVR bit rate settings info

[tvconfuse]

I'm at my wits end, I've called Hauppuage tech support, I've looked on the CD, I've searched on line and so far I haven't found anything info about the bit rate settings.

Can someone explain to me the difference between the average and peak bars in the format settings?

If i chose "constant" does it use the average or the peak bar for the bit rate?

And what is the difference between vbr average and vbr peak?

I spoke with tech support and they told me that the sharpen, contrast, brightness and etc does not work for the HD PVR. Is there anyway to sharpen the output from the capture?

I have no issues playing back the video at 1080I, no slow down and no problems with seeking, rewind, and ff.

I am using the default software that came with the HD-PVR

[lobosrul]

I don't have an HD PVR, but I can try and explain some of the things you brought up:

Difference between constant and variable BR:

Constant is just going to stick to a bitrate and stick with it. VBR will increase or decrease the bitrate depending on how much motion is in the video. It will average out to whatever the selected bitrate is however.

VBR peak is the largest bitrate that will ever be used on an VBR encoding.

Adjusting contrast, sharpening etc is something that is done on the display device (ie TV), so no you can't adjust them on the HD-PVR.

[tvconfuse]

Sorry if I wasn't being clear, I do understand what VBR and Constant is, what I'm trying to understand is how does the peak + average bar work in with the vbr peak and the vbr average profile.

for example, If i go with VBR Peak profile, and I set the average bar to 13.5 and peak at 20.2, what happens? Does it start the capture at 13.5 and then go up to 20.2?

Same thing, what happens when I go with VBR Average? I set the bar to 13.5 and peak at 20.2? Does that mean it only use 13.5 and does go higher than it?

Originally Posted by lobosrul

I don't have an HD PVR, but I can try and explain some of the things you brought up:

Difference between constant and variable BR:

Constant is just going to stick to a bitrate and stick with it. VBR will increase or decrease the bitrate depending on how much motion is in the video. It will average out to whatever the selected bitrate is however.

VBR peak is the largest bitrate that will ever be used on an VBR encoding.

Adjusting contrast, sharpening etc is something that is done on the display device (ie TV), so no you can't adjust them on the HD-PVR.

[stanger89]

The way I understand it is, in that case 13.5 is the "Target" average it will shoot for. If it can use less, it uses less, if it needs more it uses more. The 20.2 is a "cap", a limit onto how high it can go.

[tvconfuse]

Assuming that what you say is correct then what is the difference between VBR average and VBR peak if both bitrates are maxed?

Originally Posted by stanger89

The way I understand it is, in that case 13.5 is the "Target" average it will shoot for. If it can use less, it uses less, if it needs more it uses more. The 20.2 is a "cap", a limit onto how high it can go.

[dvd_maniac]

VBR average will be the average of the whole video?
VBR peak will be how high the bitrate will be allowed to go during the recording.
So if you put 13.5 average and 20.2 peak then the video will start recording at around 13.5 and will adjust higher as the motion is high and lower as the motion is lower. During the recording it will NEVER adjust higher then your peak rate of 20.2

[tvconfuse]

but what happens if you set it to VBR average profile? Does that mean it will ignore the peak bitrate bar?

And what happens if you choose the constant profile? Does it ever look at the peak bitrate bar?

Originally Posted by dvd_maniac

VBR average will be the average of the whole video?
VBR peak will be how high the bitrate will be allowed to go during the recording.
So if you put 13.5 average and 20.2 peak then the video will start recording at around 13.5 and will adjust higher as the motion is high and lower as the motion is lower. During the recording it will NEVER adjust higher then your peak rate of 20.2

[dvd_maniac]

I do not own one of these but I believe that the idea of VBR and CBR is the same.

When using VBR it needs both an average and peak bitrate.

When using CBR it uses the same bitrate across the entire recording, so it does not need a peak, since the bitrate never changes, it is the average and the peak.

[tvconfuse]

That would suck since the highest bitrate you can go on constant (based on the fact that the average bar is used for constant) is only 13.5mbs, the rest is on the peak bit rate bar.

Originally Posted by dvd_maniac

I do not own one of these but I believe that the idea of VBR and CBR is the same.

When using VBR it needs both an average and peak bitrate.

When using CBR it uses the same bitrate across the entire recording, so it does not need a peak, since the bitrate never changes, it is the average and the peak.

[stanger89]

Consider that the bitrate of most of the content you're recording with it will be either 6-8Mbps H.264 from satellite or 10-12Mbps MPEG-2 from cable. The HD PVR's bandwidth limit probably isn't the limiting factor in quality.