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VIDEO
RESTORE GUIDES -> Introduction
Before reading this guide, it needs to be understood that
restoring video is not magic. The only goal of
restoration is to create a product that looks better than
the source. Results will vary, depending on the many
factors discussed below. While one project can reap
significant changes, others may only slightly improve.
To be blunt, if you are reading this and hoping for some
miracle to turn garbage quality homemade VHS source (or bad
quality downloads) into a perfect studio-grade DVD, you are
kidding yourself. It won't happen. Again, the best that can
be expected from restoration is a final product that looks
and sounds better than the source.
There is no such thing as a "one size fits all"
method to restoring video audio or video. There is not
any software with a "restore" checkbox or filter.
This takes skill and investment into the right kind of
equipment. It will take lots of time, it will take lots of
money. There will be much trial and much error. Restoration
is what separates the dedicated video hobbyists from the
rest of the crowd. Are you ready?
Understand that the video restoration process does not
start with filters in software. While this guide may
help with already-digital files, it is aimed at those
converting damaged analog source, like ancient VHS tapes.
Restoration requires three steps: (1) purifying the video
signal, (2) a quality capture with a good capture device,
and (3) filtering the video one last time in software.
Hardware
requirements
It is almost guaranteed impossible to restore video with
average consumer equipment. Best Buy VCRs and Walmart
wires won't cut it. The basic video hardware required for
excellent quality restoration starts at about $400 US and
goes up from there. That amount is for just a few basic
items (sale-priced too!), and does not even include a decent
capture card. This fact alone turns off most people from
trying to restore video. Deal-hunters can scrape as low as
$300 if they really try. The ideal setup for a home user
wanting to guarantee himself or herself good results will
top near $1200 US for the video hardware, which again does
not include the capture card. Even deal-hunters will have a
hard time getting below a $600-700 US price tag. For most
people, especially ones wanting to tackle all kinds of
projects, expect to spend $1500 or more.
A professional or semi-professional (prosumer) VCR is the
single most important piece of equipment for restoration.
Restoration starts at the source. The best decks are
typically S-VHS decks, not because they play S-VHS, but
because they come with many embedded filters and enhancers.
Victory Company of Japan (JVC) makes some of the most
popular models, such as the HR-S9911U and SR-V10U. Many of
these also include digital noise reduction time base
correctors (DNR/TBC). This has the most affect on
“cleaning” an image.
Another useful item, if funding is available, is a
separate time base corrector (TBC), preferably a
full-field, full frame-sync model. The purpose of a TBC is
to strip the video signal of its damaged timing and insert a
new, clean timing. This will remove many motion errors, such
as jittering video and brightening/darkening of the image.
Since Macrovision (MV) is nothing more than an artificial
video error, the side effect of a TBC is MV removal. Because
many capture cards and DVD recorders are super-sensitive to
MV, owning one of these devices is becoming more common. The
DataVideo TBC-1000 and AVToolbox AVT-8710 are two good
models of TBC.
Finally, a good capture card is required. I use an
ATI All In Wonder card, which uses the high quality Theatre
chipset. I also use DVD recorders based on the high quality
LSI DiMeNsion chipset. Hauppauge, Matrox and Canopus also
make some great products. Choose carefully and do a lot of
research.
The path of the video
signal is important for restoration:
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Cheap
Method with limited results
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Source
tape -> cheap VCR heads -> playback circuitry
-> cheap wires -> cheap card -> free or cheap
software
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Optimal
Method with good results
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Source
tape -> 19-micron S-VHS VCR heads -> good
playback circuitry with audio/video playback filters
and DNR/TBC -> gold insulated Monster cables ->
frame sync TBC -> gold insulated Monster cables
-> high quality capture device -> quality
filtering/capturing software
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Software
requirements
Many video programs come with some sort of filtering
abilities, either as capture filters, or as post-process
filters. Capture filters are more limited in effectiveness,
and strain the CPU. The ATI MultiMedia Center (using the
VideoSoap option in version 8 or 9) and VirtualDub can both
use filters on capture, and are perfect for situations when
only mild corrections are needed. Post-process filters are
applied during a later encode session, after the capture is
done.
For video restoration, it is suggested to capture in
uncompressed AVI, and then apply filters during the MPEG
encoding phase. Many editors like VirtualDub, Adobe Premiere
and Vegas Video incorporate some sort of video filters. This
guide will focus on filters found in TMPGEnc, but the
techniques may apply to other software too.
Error
Glossary and Solutions
Most of these are
not technical terms. Tech terms tend to confuse people,
myself included. Many of these are descriptive and are how
things are referred to in the guide. If you know the
tech term, CONTACT US at the top of the page.
(1) Pinking/Greening: This is an error that is
normally caused from tapes that were made on cheap VCRs,
normally ones with misaligned heads or only two heads. The
top 10 percent of the image seen on screen flickers pink
and/or green. The only way to restore this error is to crop
the image so it is no longer seen. In TMPGEnc, this is done
by cropping in on the image with the crop filter. Go to the
Advanced tab, and double-click on the Crop filter. There are
three sections to this filter: Clip Frame, Arrange Settings,
and Mask Color Setting. Resized Image Used To Display should
be checked. Chop off about 20 units from the top, or however
many are needed to remove the pink noise. Go under Arrange
Settings and use either of the Full Screen options that
maintains the aspect ratio. Always maintain the aspect
ratio.
(2) Clear-Water Effect: This is an error named
because of the way it resembles ripples in clear shallow
water. Parts of the video on screen are wiggling, with such
a ripple effect. There is really no way to correct this in
the software. This is an error caused from timing errors on
the analog video tape. The DNR/TBC on S-VHS VCRs is known to
remove this. Sometimes a VCR can cause this, so try the tape
in several VCRs.
(3) Top-Screen Tearing: This is another timing error
of an analog tape, causing the top 10 to 25 percent of the
image to be distorted. The best way to fix this is by using
the DNR/TBC on an S-VHS VCR. Also try it in several VCRs, as
the deck can cause this error too. Stabilizers (like ones
built into JVC units) may help. A standalone TBC may help.
If none of these options fix it, then you will have to crop
it out, using the same method described for
pinking/greening.
(4) Red/Blue Chroma Bleeding: This error can be
caused by the VCR not getting enough power. If it is in a
surge strip with other devices, remove the other device or
plug the VCR directly into a wall outlet. If the error
persists, clean the heads of the VCR (dismantle the unit,
and gently swab the heads with an alcohol-soaked cotton swab
– do not use a “cleaner” device). If the problem is
not too severe, the DNR/TBC on an S-VHS VCR has been known
to reduce or remove it. DVD recorders using the LSI
DiMeNsion encoder chipset also remove this during the MPEG
pre-processing phase of encoding. The only fix available for
software is to reduce the color saturation. This may in fact
be needed if the hardware alone cannot correct the problem. In
TMPGEnc, under the Advanced tab, double click on the Custom
Color Correction filter. Add the YUV Saturation filter and reduce
the saturation slightly.
(5) Chroma Flux/Contrast Flux: This is where the
video gets brighter and darker, alternating every minute or
so. This is typically anti-copy (an artificial video error
like Macrovision) present on the tape, or the tape signal is
damaged. The timing of the signal is corrupts and the
automatic gain control (AGC) or the VCR is confused. A
standalone TBC will normally remove this problem. Software
cannot really fix this, not easily, not with home solutions.
(6) Vertical (Up-Down) Jitter: The timing of the
videotape is corrupted. A standalone TBC will normally
stabilize the video. The stabilizer filters in some VHS and
S-VHS VCRs can also correct this. Software cannot really fix
this, not easily, not with home solutions. There are some
Adobe Premiere and Final Cut Pro plug-ins that attempt to
correct these kinds of errors, but take countless hours of
processing, and may not correct the problems.
(7) Horizontal (Side-Side) Jitter: This error is
normally seen on copies of copies of copies … about 10
generations later. Software cannot really fix this, not
easily, not with home solutions. There are some Adobe
Premiere and Final Cut Pro plug-ins that attempt to correct
these kinds of errors, but take countless hours of
processing, and may not correct the problems.
(8) Rotational Motion/Jitter: See Horizontal Jitter.
(9) Interlace Artifacts: These are often seen on
homemade Video CDs (VCD) and other de-interlaced formats.
Before DVD was available, many video enthusiasts used this
low-resolution format, often butchering their video in the
process. As explained in the capture guides, de-interlacing
has a very negative affect on video, as it is essentially a
process of throwing away half of the video data. The
de-interlace leaves stair-steps on curved lines. Because
these stair steps tend to look alive on screen, often moving
erratically, they are worth removing. The best that can be
done is to hide this damage, using a combination of several
TMPGEnc filters. The side affect is softer video, but
television sets are already soft focus playback devices, so
it should not be too noticeable. Open TMPGEnc, go the
Advanced tab under settings, and double-click on the Sharpen
Edge filter. Move the vertical sharpen to the most negative
setting. Move the horizontal sharpen to halfway between zero
and the most negative number. Click OK, and then go to the
Deinterlace filters. Select a Double de-interlace filter. A
double (blended/merge) de-interlace filters will smoothen
progressive video. On the Quantize Matrix tab, enable 25-75
block noise softening. Finally, some noise reduction may
help using the Noise Reduction filter, maybe a setting of
40-2-40.
(10) Macroblock Artifacts (Digital Grain): Macroblocks
are the artifacts made from having inadequate bit-rate for
compressing MPEG at a certain resolution. Noise reduction
filters found in TMPGEnc and VirtualDub are excellent are
removing noise
(11) Analog Grain: Much like macroblocks, noise
reduction filters can remove grain from analog sources.
Analog noise/grain is inherently native to the format.
Analog is lossy.
(12) Color Loss and Color Shift: Color problems,
while they look like the hardest things to fix, are actually
one of the easier problems to correct. There is typically
not one single filter that can correct the issues, but a
chain of several filters may do the trick. The TMPGEnc
Custom Color Correction filter is an excellent tool for
this. You can add as many filters as you need to correct an
issues. Even the most serious color problems. A good proc
amp can also fix this.
(13) Tape Tracking Errors: This can only be corrected
by using a better VCR. If the tape is damaged beyond repair,
capture as best as possible, and then crop out the bad area.
Follow the instructions given for the pinking/greening
error.
(14) Static Lines: These are little glitches seen on
screen. It is caused from the tape particles coming off the
tape, leaving these little static lines behind. There is no
data available, in fact there is no tape available. This is
most often seen on tapes that have been re-used several
times. It can also happen on cheaps tape used in S-VHS-ET
recording mode. Nothing can be done about this except to use
better tapes and not make the mistake again. Some
professional DV devices (Matrox and Canopus) have been known
to replace this drop-out with information from the previous
or following frame.
(15) TV Snow Grain: See Analog Grain
(16) Image Ghosting: There is really no way to remove
ghosting with hardware or software. While both S-VHS VCRs
and software have “ghost reduction” filters, they do
almost nothing. This error is typically caused from
power-related problems or grounding issues with coaxial
cables. The best fix is normally to replace cables with
better-shielded cables. Use RG6 and not cheap RG59 coax. Use
gold plated, and insulated, s-video and composite video
cables. Be sure the power signal is clean, consider getting
a power filter for the electrical outlet. Some hardware
detailers have been known to help minimize this error.
(17) Color Bleeding: This is caused from degraded VHS
tapes, and is normally fixed with a color correction.
Desaturating the video slightly and lightening the gamma of
the image, both available in the TMPGEnc color filters, will
lesser than harshness of the error.
(18) Non-Errors: A non-error is typically caused from
user error. It’s not truly a video error – it’s an
error between the chair and the keyboard. Digital mistakes,
like reverse interlace and dropped frames, cannot be fixed
in software. The way to correct these issues is to properly
encode or capture the first time around.
Conclusion
Video restoration is an advanced aspect of video conversion,
one that comes with a hefty price tag and requires lots of
patience. There is not a “restore” button in software
that will magically restore video. Although “garbage in,
garbage out” is a very true statement, it can be tweaked a
bit to “garbage in, better-than-garbage out.” The entire
goal of restoring video is to simply make it better, not to
make it perfect – mainly because perfection is impossible.
There are many kinds of video errors, and 18 of the most
common ones have been listed in this guide, complete with
solutions.
Page Last Updated: March 14th 2005
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