Converting VHS to XviD - awful quality

[Zippy1970]

I'm trying to capture and convert an old movie I have on VHS tape to an XviD file. I first captured the VHS tape through composite video using a MJPEG codec and a de-interlace filter. Reason being that this gives me a near lossless result while getting a reasonable compression ratio, so it doesn't give me a huge file. Also, I can't directly capture to XviD because of the filtering and I get a lot of dropped frames when I try.

So I now have a 6Gb MJPEG file which has only a slightly worse quality than the original.

The source itself is pretty bad. I'm not sure if this is because it's an old tape, or because of the quality of the VCR or because VHS simply can't do any better. I guess it's a combination of all three. So there's a lot of noise in the source and the image is a bit jumpy. All this makes compressing it pretty difficult.

I'm using VirtualDub together with FFDShow. I'm aiming for a filesize of around 700Mb so it will fit on a single CD. The movie itself is 1h40m.

To get rid of some of the noise, I'm using a de-noise filter which works quite well (in FFDShow it's called "Gradual denoise" and it's set to 40).

So far I've tried two-pass encoding and single pass encoding. The result of both isn't very good and I get a lot of compression artifacts and the image is *really* blocky and has lost quite a bit of color depth (the first image is the MJPEG source, the second image is after converting to XviD):



Is this the best I can expect from a VHS source? Or could anyone give me some tips how to get a better color depth and a better quality?

[DB83]

1. De-interlacing creates soft images

2. Removing noise softens the image even more.

But it looks like your data-rate is too low or your video frame size is too large or it is a combination of both. 700 mb for 100 minutes is possible but usually from a good quality dvd and then at a reduced frame size. What are these parameters ? Vdub or mediainfo will tell you this information

[jagabo]

You won't be able to get a 100 minute VHS video down to a 700 MB 640x480 Xvid file with any quality. VHS is just too noisy, and noise is the enemy of compression. You also have a serious black level problem. The black level in MJPEG file is probably a little too dark (hard to say for sure with just one frame) and in the Xvid file it's too light.

[Relayerman]

I do the same kind of conversions all the time (VHS to Xvid via MPEG-2 file). I use AutoGK so can't really apply filters per se, but yes, 700mb file for a movie that long will produce results like you show. I tend to try for the 1/4 DVD which is around 1100mb size. This works very well for VHS IMHO.

[DarrellS]

Both frames are way too dark and the bitrate is way too low for the XviD.

[Zippy1970]

Ok, I'm sorry I didn't provide more information.

The example picture was from a night scene so it's supposed to be dark. I just used it as an example because the blockiness was very noticeable. Here is an example from a "normal" scene:




And here's the output of MediaInfo for the XviD file:

General
Complete name                    : C:\Documents and Settings\Owner\TATR_Q65.avi
Format                           : AVI
Format/Info                      : Audio Video Interleave
File size                        : 728 MiB
Duration                         : 1h 40mn
Overal bit rate                  : 1013 Kbps
Writing library                  : VirtualDub build 29808/release

Video
Format                           : MPEG-4 Visual
Format profile                   : Simple@L1
Format settings, BVOP            : No
Format settings, QPel            : No
Format settings, GMC             : No warppoints
Format settings, Matrix          : Default
Codec ID                         : XVID
Codec ID/Hint                    : XviD
Duration                         : 1h 40mn
Bit rate                         : 945 Kbps
Width                            : 640 pixels
Height                           : 480 pixels
Display aspect ratio             : 4/3
Frame rate                       : 30.113 fps
Resolution                       : 8 bits
Colorimetry                      : 4:2:0
Scan type                        : Progressive
Bits/(Pixel*Frame)               : 0.102
Stream size                      : 679 MiB
Writing library                  : Lavc51.57.2

Audio
Format                           : MPEG Audio
Format version                   : Version 2
Format profile                   : Layer 3
Codec ID                         : 55
Codec ID/Hint                    : MP3
Duration                         : 1h 40mn
Bit rate mode                    : Constant
Bit rate                         : 56.0 Kbps
Channel(s)                       : 2 channels
Sampling rate                    : 22.05 KHz
Resolution                       : 16 bits
Stream size                      : 40.2 MiB

[poisondeathray]

I agree with DarrellS that the bitrate is too low. You can get away with a lower bitrate if your source quality is good, but in your case you have to compensate with a much higher bitrate

The other option (if you were fixated on the 1CD size) is to use h.264 instead of DivX, which has inloop blocking at gives much better quality at lower bitrates than DivX. The negatives are high CPU utilization and usually low compatibility with most standalone units. You can try a encode small 1 min sample to see the difference; i bet you don't even need a de-noise filter with h.264

[Zippy1970]

The reason I wanted it to fit on a single CD was because I thought I could. If that's really stretching it, than I'm more than willing to let that go.

SO for really noisy VHS, what would be a more realistic filesize?

[poisondeathray]

Impossible to answer that question, too many variables, and subjective tastes involved.

If I were you, I would encode small representative 30sec samples under different settings until you find a combination right for you for that particular input. Is quality more important to you or filesize? If you want a set filesize you have to use 2-pass mode; if you want a set quality, a constant quality mode is usually better.

[DarrellS]

I usually use a quantizer of at least 4 (default) and 2 for quality sources. If using bitrate instead of quantizer, I use at least 2000 kbps for full resolution AVI (640x480).

I put AVI that I can't get down to CD size on a DVD as data and play on my Philips DivX player. Cheap DVDs that I can't use for Video DVDs work well for me as Data DVDs. I have both Ritek and Ridata that suck for DVD but I've had no problems as Data DVDs.

[jagabo]

I recommend you use constant quality encoding. Pick a quality level you're happy with and encode. In Xvid I usually use a target quantizer of 3. Sometimes 2 for something I want to be really clean (the lower the quantizer, the highe the quality), and occasionally 4 for something unimportant. You can use anywhere from 1 to 31 in Xvid.

[meldavid]

What do you guys think is the optimum resolution to resize to weighing up the balance between compression and picture quality?

Say your source is PAL VHS, wouldn't 640x480 Xvid be too high a resolution, hence wasting disk space? I read in a wikki that VHS is, digitally, roughly equivalent to 320 pixel horizontal resolution.

So would resizing to ~ 424x320 be optimum?

[jagabo]

PAL VHS has 576 lines of resolution vertically, roughly 320 horizontally. But you deinterlaced so you may have as little as 288 lines on the vertical axis (depending on how you deinterlaced). You might get away with as little as 384x288.

[Marvingj]

use constant quality encoding ( I'm in agreement)

[meldavid]

I used LeakKernelDeint(), default settings. I suppose I should encode a few at different sizes and compare, but I'm using NeatVideo plugin and it takes sooo long, lol.

[jagabo]

I used LeakKernelDeint(), default settings.

Yeah, I thought the samples looked better than 288 lines.

I suppose I should encode a few at different sizes and compare, but I'm using NeatVideo plugin and it takes sooo long, lol.

For testing, using single pass target quantizer encoding will allow you to encode short segments very quickly.

And, as has been mentioned before, you need to fix the problem with the black level in your Xvid encodes.

[victoriabears]

Back to basics.

What brand of VCR was it recorded on

What brand / model are you playing it back on.

Are you recording to highest MPeg opn a dvd recorder, capturing on a pc ?

I did a VHS, average equality, at XP on my Philips dvd recorder 3575, and then used auto GK to convert to xvid at 700MB got 90 minutes is a good low scale, or 700MB for 60 minutes, came out great.

[lordsmurf]

A better VCR would help here.

[meldavid]

Hi, I'm not the original poster. I just hijacked this thread to ask a general question about optimum target resolution to convert VHS to Xvid. Those aren't my samples, lol.

My setup is follows:

LG GC990W Multisystem Hi-Fi VCR
Canopus ADVC110
Sony Video Capture 6.0

AviSynth: Crop, Neat Video, LeakKernelDeint, LanczosResize > VirtualDub

I've had good results converting to Xvid. However I tended to use 512x384 as the target resolution for Xvid, using a constant quantizer of 2.29 with max of 2 B-Frames.
The file sizes tend to be pretty large. I just want to know how much I can decrease the Xvid resolution without throwing out detail.

If PAL VHS is recorded at 320x576 (is that right?) then what would be the optimum resolution for encoding to Xvid?

[lordsmurf]

" I just want to know how much I can decrease the Xvid resolution without throwing out detail. "

You really cannot. In fact, you're already suffering some loss.

[jagabo]

If PAL VHS is recorded at 320x576 (is that right?) then what would be the optimum resolution for encoding to Xvid?

320x576 with 4:3 DAR flag.

[meldavid]

Ok, just to clarify, I am not capturing at 320x576 but actually 720x576 DV.
When I mention the number 320 it is because of what I've read that the VHS format has roughly the digital equivalent of 320 horizontal lines. Then I read threads like here and some say that VHS is 423 x 480 (for NTSC) which would be 423 x 576 for PAL. But 352 is actually close enough and is a MPEG2 half-D1 standard.
So you see why I am getting confused with picking my target Xvid resolutions, lol.

I think I may just deinterlace, resize to 352x576, crop to mod16 and get rid of overscan areas, and be done with it. And set the AR flag as well.

[lordsmurf]

Anything in the 400+ range is over-analysis and theoretical mumbo-jumbo only. It is actually UNDER 352x480, but 352x480 is the closest DVD-spec resolution. In terms of XVID, it's really an exercise in experimenting. For example, losing your interlace is the worst damage possible to VHS source.

[Nightshiver]

How about uploading a small unaltered video clip?

[meldavid]

Here you'll find a sample of the original DV capture from VHS.

Then there's an Xvid 512x384 which is what I've usually been encoding to for 4:3 sources.

And there's an Xvid 352x384 which I tried last night set with a DAR flag of 4:3.

When I compare the two Xvids they are almost exactly the same. The only difference I've noticed is slightly more motion judder on horizontal landscape pans. However I'm annoyed that the 4:3 DAR flag is ignored by Quicktime (Perian plugin) when I try to view the movie on my iMac. My stand-alone HD media player plays the movie at correct aspect however.

I think square pixels are more universal for Xvid files. I'm encoding a 384x288 file right now to see how it would look on my TV. I am happy with the PQ of 512x384 but movies end up being ~1.1GB for 60 mins.

[jagabo]

Yes, square pixel is more universal with Xvid. Many players don't respond to the aspect ratio flag.

Load_Stdcall_plugin("C:\Program Files\AviSynth 2.5\plugins\yadif.dll")

AVISource("C:\Documents and Settings\John\Desktop\DV.avi")

ColorYUV(off_y=-16)
ChromaShift(C=-6, L=-4)
Yadif(order=1, mode=0)
Crop(16, 12, -12, -18)
LanczosResize(512, 384)

Followed by Neat Video in VirtualDub, Xvid, target quantizer=3:

http://www.sendspace.com/file/y585bn

Yadif() is a little better than LeakKernelDeint(). Notice how the line at the top of the belt buzzes less than your 512x384 sample. I shifted the chroma channels to better align them with the luma and adjusted the black level. Neat Video was probably a little too aggressive here but you can fine tune it.

[meldavid]

Wow, yeah, definite improvement! I've always been shy of using lower than Q=3 except for B-frames but you've shown me it still keeps the PQ. I'll do a re-encode right away with your enhancements.
This VHS capture also goes brighter or darker every few minutes (copy-protection) but I'm not going to bother about that as it's not really that annoying.
Thanks for the help, much appreciated.