Optimal bitrate for Theater 550 pro

[blizard]

What is the optimal setting for bitrate for LiveTV and to record with? I can not see much difference between constant bitrate at 12000 and around 2900 for LiveTV preview on the image quality. The only difference are that my dual core have to work more at something around 15-20 % CPU (Athlon64 X2 4200+@2200) instead of the lower 10%.

For recording I use VBR at 2500 with peak at 3700 at medium quality setting. Would constant bitrate provide better result or even be better to for Xvid/h.264 transcoding?

Does the level of bitrate have anything to do later when I transcode to other format like Xvid or h.264?

I would appreciate if some one else then sub could give their own experience on this. System spec are in signature.

[csy]

This is my recording experience with my TUL/Powercolor Theatre 550 Pro.

8-12Mb/s VBR: sharp on low motion scenes but blocky on fast moving scenes
8Mb/s CBR: equal sharpness as 8-12Mb/s VBR, and no blockyness on fast scenes
5-8Mb/s VBR: equal sharpness as 8-12Mb/s VBR on low motion scenes, but blocky and bit fuzzy on fast moving scenes
5Mb/s CBR: equal sharpness as 8-12Mb/s VBR on low motion scenes, but a bit fuzzy on fast moving scenes and no blockyness
4Mb/s CBR: bit fuzzy on low motion scenes, and more fuzzy on fast moving scenes and no blockyness.

My conclusions:
1) The 550 can't do VBR very well with resulting blocky picture on fast moving scenes, therefore I only use CBR
2) Best quality is at 8Mb/s CBR, and this is what I use for LiveTV Preview mode with 'encoder pass-through'
3) 5Mb/s is a good compromise between picture quality and filesize, and this is what I use for general recordings that will not be permanently saved
4) Below 5Mb/s reduces overall sharpness to below that of my standalone TV, and therefore defeats all the time and money I spent on setting-up my HTPC. I therefore consider 5Mb/s to be my minimum record quality.

Recordings that I intend to save are recorded @8Mb/s CBR for best quality, then transcoded to H.264 (MPEG4-AVC). Through experimentation I have found that I can transcode 8Mb/s MPEG2 to 1Mb/s H.264 without noticing any loss of picture quality. In other words, my 1Mb/s H.264 recordings have the same picture quality as 8Mb/s MPEG2 but at a fraction of the filesize.

[blizard]

Thanks CSY!

You confirm what I also have experienced. I set my LiveTV to 6 Mb/s and 7 Mb/s for medium recording. That gave me an explosion in size for Timeshift recoding and I had to move my LiveTV folder to another partition as my GBPVR partition at 2 GB was too small for it.

I find VBR to be very good in some cases as it demand less space, but it is impossible to know how good the end result will be with so many types of recording (slow/fast moving objects; light/dark parts and different type of interlaced material from broadcaster -which could be out of control from broadcaster as it is dependent on other sources according to this website).

Do you use the other option for setting of recording like "low" and "high"? I can not see the big use for my part as I never know if it is worth to keep later and I hate to record something that I should have had on high. Default/medium is what I use for all my recording.

Do you know if Timehift>recording will use the same medium setting or are they different? How does LiveTV>Timeshift work with bitrate setting?

Right now I use FFDSHOW and SUPER for decoding/encoding. Is there any better software for transcoding? Would Auto Gordian Knot work better or faster? SUPER with its own codec seem to not work well when set to DirectShow. I transcoded one movie with SUPER from 1.7 GB to 356 MB (Cartoon; H.264/AVC) with the internal codec in SUPER, but it didn't work with external directshow.

As I have a 64 bit OS and CPU, would there be any gain to use FFDSHOW with support for 64 bit? Is there any codec pack that support this like K-Lite Mega codec does for 32 bit? I saw this Advanced Vista Codec Package 4.2.0 (link to developer of this package). I have win XP x64 and not Vista, but it seem that it would support x64 and from what I have seen there should some gain in transcoding speed. Is this worth the effort to install?

Any recommendation for transcoding?

[csy]

Do you use the other option for setting of recording like "low" and "high"?

I have configured High=8Mb/s CBR, and Default/medium=5Mb/s CBR
(the bitrates are configured in GBPVR Capture Source configuration)
I record my TV shows that I intend to watch/delete using default, and TV movies that I intend on keeping using 'high'

Do you know if Timehift>recording will use the same medium setting or are they different? How does LiveTV>Timeshift work with bitrate setting?

LiveTV>Timeshift does use a different setting, it uses the 'LiveTV Quality' setting in GBPVR Capture Source configuration

Also note the LiveTV Preview mode 'encoder pass-through' bitrate setting is a different setting again, and can only be configured in config.xml. From memory this has a default of 6-9Mb/s VBR which I manually edit to 8Mb/s CBR.

Right now I use FFDSHOW and SUPER for decoding/encoding. Is there any better software for transcoding? Would Auto Gordian Knot work better or faster? Any recommendation for transcoding?

I'm on the lookout for something better myself. I'm currently using Nero Recode (part of Nero 7.2), but it doesn't support interlaced transcoding, so it always software-deinterlaces the MPEG2 before transcoding and does a very poor job of the deinterlacing which spoils the transcoded picture quality. Let me know if you find something that works well and most importantly easy to drive

As I have a 64 bit OS and CPU, would there be any gain to use FFDSHOW with support for 64 bit? Is there any codec pack that support this like K-Lite Mega codec does for 32 bit? I saw this Advanced Vista Codec Package 4.2.0 (link to developer of this package). I have win XP x64 and not Vista, but it seem that it would support x64 and from what I have seen there should some gain in transcoding speed. Is this worth the effort to install?

The short answer is - I don't know. I'm about to purchase Vista and am keen to go 64bit based on the same hopes that it might be able to reduce transcoding times, but the lack of driver support looks like will block me from going 64bit at the moment.

[creep]

CSY:

Would you mind posting your playback settings? And also your deinterlace settings?

I'm reading through your posts and you seem to be the ATI550 expert.

I have a Radeon 9600Pro and a 550Pro, i'm trying to tweak the picture qualty and fix my "sometimes" jerky playback.

My settings for the 9600 are:

From what i gather from the threads i've searched, It's best to force hardware deinterlacing. Correct?

I'm using the cyberlink decoder from PowerDVD 7.2 and VMR9 Custom.
I've selected force weave in the advanced decoder settings.

Is there anything else on the playback page that i should "try" too provide a better picture?

I also have my deinterlace setting in the "misc" tab set to "None". Should i be using encoder_pass_through?


Thank you.

[sub]

I also have my deinterlace setting in the "misc" tab set to "None". Should i be using encoder_pass_through?

You've posted this same question three times in the last hour. I answered the first one.

[creep]

3? I thought i replied to 2 threads about the deinterlace settings.... hmmm.

At any rate, sorry about that.

So what about the video decoder? In the opinion of the 550 users, which decoder seems to provide the sharpest picture?

Are there any other tweaks in CCC i should look into?

[sub]

3? I thought i replied to 2 threads about the deinterlace settings.... hmmm.

It's in each of these three posts:
http://forums.gbpvr.com/showpost.php?p=2...stcount=13
http://forums.gbpvr.com/showpost.php?p=2...ostcount=5
http://forums.gbpvr.com/showpost.php?p=2...stcount=13

[csy]

@creep

Sorry but I cannot offer any advise at the moment because I'm not currently using GBPVR.