How can I improve the quality of analogue TV captures? [Archive]

View Full Version : How can I improve the quality of analogue TV captures?

lonegeek

8th January 2006, 19:44

I have a hauppauge pvr 250 that i record tv shows with , I only have basic cable the quality is shite. I record it at Mpeg 2 video:720x480 , 29.97 fps, 5250 kbps
Mpeg 1 Audio layer II (MP2) 48000Hz, 2 ch, 224 kbps

Is there anyway to improve the quality when encoding to xvid. Some shows turn out brighter and better looking but others turn out washed out.. Im using autogk at 1/4 cd (175mb)

Any ideas?

thanks , zach

Teegedeck

8th January 2006, 19:57

AFAIK there's no automated method to do that, and certainly not within a video codec. AviSynth filtering is what you'll have to get used to. For example try learning how to handle DGMPGDec's inbuilt postprocessing, to improve contrasts with Didée's 'YLevels' script and to denoise with RemoveDust or PixieDust.

Anyway, I think the most specialised help you'll get in the 'AviSynth Usage' subforum, so I'm gonna move your post there. I'm also gonna change the title of your post to something more specific, so don't be alarmed about it having changed.

BigDid

8th January 2006, 21:03

I have a hauppauge pvr 250 ...I record it at Mpeg 2 video:720x480 , 29.97 fps, 5250 kbps Mpeg 1 Audio layer II (MP2) 48000Hz, 2 ch, 224 kbps
Hi Zach and welcome to the forums,

The hauppage pvr250 is, I believe, mpg2 hard encoding so you should be able to raise the bitrate, gain source quality and also need more room on your HD. I'am in a Pal land my settings (soft mpg2 encoding) are 720x576 25fps, up to 9500kbps (usually use 9000) with audio MP2 384kbps. If I want more audio quality than video I use 8200kbps and lpcm audio.
This is related to the forums capturing videos and/or non linear editing, you may find more infos there.

Is there anyway to improve the quality when encoding to xvid. Some shows turn out brighter and better looking but others turn out washed out.. Im using autogk at 1/4 cd (175mb)...
Now this is more complex, related to xvid I enforce teegedeck comments on avisynth filtering, you may want to start with a (quite) easy solution within autogk: AGKPal/AgkTweaker, see my post related here: http://forum.doom9.org/showthread.php?p=761195#post761195

Related to AGK, do you use the hidden settings (ctrl-f9)?
If not look in your tutorial or here: http://www.autogk.me.uk/modules.php?name=TutorialEN (other langages available)
Quality related settings can be:
- sharp matrix
- encode credits with differents settings
- tune up auto crop parameters
Useful color param: -correct color if needed (use accurate option)
This is related to the AutoGK forums, you may find more infos there

Not related to AGK are the usual recommandations concerning bitrate, within AGK I use bitrate for final avi between 800 to 1500kbps and I use some filtering to reduce the artifacts or enhance details.
Other people will have other recommandations mine are justified because:
- below 800 I usually don't have enough visual quality on my screen
- above 1500 I may have stuttering on my standalone player (SAP)
So I toggle between these values and the audio bitrate to get average to good quality and raise or decrease my encoding size accordingly.

Happy new year and happy encoding :)

Did

Boulder

8th January 2006, 21:17

Go for the max bitrate when capturing, 12Mbps CBR. Also capture audio at 384kbps, stereo, as you need to re-encode it anyway.

I'd give LRemoveDust or DegrainMedian a go for cleaning the video. The card does denoising during capture, something I never liked. There are tools on the net that can be used to tweak the noise reduction settings if you like.

lonegeek

8th January 2006, 21:45

Hmmm Those sound pretty dificult to do.... I'll try increasing tv recording quality..

IS there any easy way to do this? I record alot of tv shows...

Firesurfer

8th January 2006, 21:59

Hi,

I record a lot of tv-shows with a pvr350. The way that I find gives the best quality is raising recording bitrate up to 15000 and turn off any preprocessing. I'm using WinTvCap for that. After that I demux with ProjectX, cut commercials with Cuttermaran, use avisynth with fft3dgpu and degrainmedian for postprocessing and reencode to desired size with HCenc.

This may be a complicated way to do it, but I never found a pvr card to produce dvd-ready quality.

I'm quite willing to give more detail if you want to, but honestly I'm too tired now ;-)

lonegeek

8th January 2006, 22:22

Whats your tv source? Coudl i possibly see a sample of that video??

aim me
asinitepunker

msn me

lone.geek@hotmail.com

Please help out a fellow hauppauger lol

lonegeek

9th January 2006, 03:15

BigDid

10th January 2006, 01:10

Hi,

Before asking new questions, could you consider answering to the contributors or indicate if your first questions/subjects are answered/resolved? :rolleyes:

Also :search: , :readguid: or :readfaq:
like:
http://forum.doom9.org/showthread.php?t=25002
or
http://forum.doom9.org/showthread.php?t=96451 ...
:thanks:

Did

Firesurfer

16th January 2006, 10:34

@lonegeek

I promised details of the way I produce my dvds, but at the moment, there's just no time, I'm really sorry. On the other hand I, too, think you should do a bit of reading in this forum before you ask such a basic question.

My standard script looks like this:

mpeg2source("somewhere\blahblah.d2v")
ColorMatrix()
AutoCrop(mode=0,threshold=50,samples=10)
h=(720-width(last))/2
v=(576-height(last))/2
#DeGrainMedian(limitY=5,limitUV=5,mode=1)
DeGrainMedian(limitY=5,limitUV=5,mode=1)
aSharp(1,1)
AddBorders(h,v,h,v)
ColorYUV(levels="pc->tv")

Sometimes the source needs the second degrainmedian, sometimes it doesn't let your eyes be your guide.