Panasonic
D-snap SV-AV100 SD Video Camera
- MPEG-2 and MPEG-4 video
- SD (Secure Digital) memory cards
by Douglas Dixon
SD
Small
Shooting with the
SV-100
SV-100 Formats
MediaStage Software
D-snap Wrap
References
How
small can video camcorders go? Moving from the 8mm tape
cassette to the smaller DV tape size allowed camcorders to
shrink down to around the size of a thick (but heavy)
paperback book. Not small enough? OK, well then Sony
introduced the matchbox-sized MICROMV
cassette, permitting the camcorder to shrink even further,
dropping under a pound to a size small enough to carry in an
outer coat pocket. While you could imagine new products with
even smaller tapes, any tape-based camcorder will require all
those delicate spinning mechanical parts for the tape
transport, which increases the size and cost, as well as the
risk of something breaking. Another option that is being tried
in recent products is to record to DVD disc, but accommodating
even the half-size mini-DVD disc results in a more bulky
camcorder design.
A
better answer is to abandon all forms of winding or spinning
media, and move to solid state -- the same kinds of memory
cards that are now ubiquitous with digital cameras. By getting
rid of all the mechanical parts for the tape transport, you
can totally demolish the size barrier, and design products
like the new Panasonic D-snap SV-AV100 SD video camera
-- a literally palm-sized camera that weighs about a third of
a pound. At this size, it indeed fits in a shirt pocket, and
you're now comparing the form factor of a video camera to a
bar of soap!
 
The
AV100 is one of two "D-snap" products from
Panasonic (www.panasonic.com/d-snap),
introduced in September 2003, that set new benchmarks in
miniaturization using SD (Secure Digital) memory cards (www.panasonic.com/sd).
The D-snap family also includes a digital camera, the SV-AS10,
shrunk to a size of 2 x 4 x 1/2 inch, and weighing around 2
ounces. It shoots 2-megapixel stills, plus Motion-JPEG video,
and also can be used as a music player and voice recorder. The
AS10 digital camera has a list price of $299, and the AV100
video camera we're discussing here lists at $999.
The
advantage of using solid state storage for video cameras is
that you can get rid of all the clunky mechanical components
of a tape-based camcorder, greatly simplifying the design and
therefore significantly reducing the size. At this point, the
limiting factors in the design become the lens, view screen,
and battery. The other limitation, of course, is usability --
the danger of shrinking the unit and controls so much that you
can't hold it comfortably or steady, and can't find or press
the buttons reliably.
The
disadvantage of solid-state camcorders is that these tiny
memory cards -- with form factors like a thick postage stamp
or a small stick of gum -- cannot store anything like the
amount of data that you can spool onto a one-hour DV tape, and
are hugely more expensive. For example, DV video requires 25
Mbits/sec, or 11 GB per hour. Even more compressed MPEG-2
video at 6 Mbits/sec requires 2.6 GB per hour of storage.
Today's commonly-available memory cards store up to 512 MB
(SD) or 1 GB (Memory Stick PRO), at prices around $350 to
$600, respectively. That's $600 to hold less than one-tenth of
the capacity of a DV tape. Ouch!
Put
that way, why are we talking about solid-state camcorders at
all? While they clearly are not going to replace DV for
high-quality extended recording, there still is a place for a
much lighter and more portable camcorder that you can use for
capturing shorter clips. And memory card capacities continue
to double and redouble, and prices continue to drop, so this
approach will only get better over time.
For
such a small and light camcorder, the SV-100 is quite
effectively designed for handling by clumsy human fingers. All
the external connectors -- power, USB, AV in/out -- are out of
the way on the front of the unit, protected by plastic covers,
and the SD card is under a flap on the bottom. The AV jack
supports playback to TV, recording from A/V input, and audio
out to earphones. The largest elements are on the sides: the
flat battery on one side, and the fold-out 2 1/2 inch LCD
display on the other side (there's no viewfinder).
External connectors
The
SV-100's playback and menu controls are simplified to a few
buttons, placed on the side under the LCD. There's a dedicated
button for switching between Record and Playback modes, a
button for cycling between the recording modes (MPEG-2,
MPEG-4, and still Picture), and a third button for accessing
the menu display on the LCD. Then the SV-100 uses a
four-position Multi-function button for playback and menu
selection controls: press the center to Play or Set, or the
four compass points to rewind / forward / pause / stop, or to
navigate the menus. All quite accessible and intuitive.
Play Controls
The
SV-100 menus provide access to a wide range of recording
features, including digital zoom, backlight compensation,
white balance, program auto exposure, manual exposure, manual
focus, digital electronic image stabilization, and even wind
noise reduction. While you need to go into the menus to select
most of these modes, the current settings are shown as
indicators over the video on the LCD display.
To
shoot with the SV-100, flip the LCD so that it faces the back
of the unit. Again, the few key buttons you need for the task
are positioned on the back of the unit: Power On/Off, Record
Start/Stop, Zoom In/Out, and Auto/Manual Focus/White Balance.
To adjust the focus or white balance, toggle the Manual slider
to select Focus or White Balance on the LCD, and then use the
Multi-function button to adjust the setting. You also can use
the Multi-function button to toggle backlight compensation.
Rear controls
So
now it's a matter of figuring out how to hold the unit. You
can rest it in your right palm, and your fingers wrap
naturally around the front under the lens ring (but also
covering the Recording Lamp red light that indicates you are
recording). I found that in order to position the thumb on the
Record and Zoom controls, it was best to twist the unit
diagonally in my hand, so the thumb lies along the back of the
unit and the index finger actually goes over the top. This
allows you to hold and control the camcorder with one hand,
and use the end of the thumb to slide between the Record and
Zoom controls. Otherwise, you'll find you need to reposition
your fingers to hit the Record button, so each recording will
begin and end with some shaking around as you adjust your
hold.
The
other issue with such a small and light camcorder, of course,
is shakiness as you shoot. It's just hard to brace a bar of
soap and hold it steady. You can use your other hand to hold
the other side of the unit, or I found that holding the
folded-out LCD display with the thumb and index finger of my
left hand helped me to both steady and frame the shot.
For
a small camera and lens, the SV-100 does have an impressive
10:1 optical zoom to get in rather close, to approximately 1
3/8-inch. The lens is F1.8-2.3, with a focal length of
2.3-23.0 mm, delivering light to a 1/6 inch CCD image sensor.
The next issue, then, is how the light is stored and
compressed on the memory card.
Providing
reasonable recording times for a camcorder requires the same
approach used for digital cameras: compressing the digital
data efficiently, and offering choices to trade off the amount
and quality of the recorded material -- in this case adjusting
the compression formats, resolutions, and capture rates. The
SV-100 provides recording times of 10 to 20 minutes for almost
full-screen MPEG-2 on the included 512 MB SD card, and
extended times of 1 to 10 hours using MPEG-4 video format at
lower res and lower rates.
The
higher-quality compression format used by the SV-100 is MPEG-2,
the same compression approach used for DVD and much of cable
and satellite television. It records in "Fine" mode
at 704 x 480 resolution, and "Normal" mode at
352 x 480 resolution, which can fit about 10 or 20
minutes respectively on a 512 MB SD card. These compress the
video at approximately 6 and 3 Mbps, at constant bit
rate, so in "Fine" mode you're getting less
horizontal resolution than normal NTSC DVD (740 x 480),
compressed in the camcorder hardware somewhat more
aggressively than a typical DVD (6 to 8 Mbps, but with
variable bit rate, and often with multi-pass compression). As
a result, all else being equal, you should not expect this
compressed video to look as good as DV, or even DV converted
to MPEG.
The
SV-100 also offers the MPEG-4 compression format for
longer recordings. The MPEG-4 format was designed to
accommodate a broader range of uses than MPEG-2, from
streaming video up to digital cinema, and down to hand-held
PDAs and wireless phones. The SV-100 offers four MPEG-4 modes,
"Fine" 320 x 240 resolution at 15 and 12
frames per second, and "Normal" 176 x 144
resolution at 12 and 6 fps. These use compression rates
of 1 Mbps, and 420, 300, and 100 Kbps, respectively,
providing recording times of 1 hour, 2:20, 3:30, and up to
10:10 on a 512 MB SD card.
For
audio recording, the SV-100 uses standard MPEG audio
with MPEG-2 video (MPEG-1 Layer 2), and G.726 with
MPEG-4.
The
SV-100 also offers still recording modes, 640 x 480 JPEG
compression, storing up to 3520 pictures in "Fine"
mode, and 7040 in "Normal" mode on a 512 MB SD card.
Once
you've shot video on the SV-100, there still remains the
question of how to get it back out, and what you can then do
with it. You can use the A/V output to play analog video out
to a TV or VCR. You also can remove the SD card and insert it
in another device with a SD slot, to display photos or maybe
the videos on a compatible device with a SD slot, such as a
TV, VCR / DVD player, or portable multi AV player.
You
also can use the included USB cable to access and transfer the
clips to a personal computer (there's no FireWire). The
included software requires Windows 98SE or later, and includes
a USB driver and the MediaStage viewing application. The USB
driver mounts the SV-100 and its memory card as a virtual
device under Windows (as with a digital camera), so you can
directly access the files recorded on the card from Windows
Explorer. You then can copy the files from the SD card to hard
disk (and then burn the data files to CD or DVD as backups).
Each of the three media types is stored in a different
directory on the card: still images (.JPG), MPEG-2 video
(.MOD), and MPEG-4 video (.ASF). All of these files then can
be played directly under Windows (though you do need to rename
the MPEG-2 files from .MOD to .MPG).
You
also can use the included MediaStage software to access
and view the contents of the SD card. However, MediaStage is
very basic: You can preview the clips captured on the SD card,
copy to the hard disk, do simple trims to remove the beginning
or ends of clips (typically because they are shaky), and
create playlists by assembling a sequence of clips.
 MediaStage:
View SD
You
can store the results back on the SD card, or export clips,
but only in MPEG-4 and Windows Media (WMV) formats. The
interface also is overly "friendly," for example,
hiding the directory where the files are being stored on the
hard disk.
MediaStage: Trim
If
you really want to edit the resulting clips, things get
trickier. Even the higher-resolution MPEG format is not
full-width, so will need to be stretched to match DV or DVD
resolution. In addition, many video tools do not work well
with native MPEG-2 format, and especially not MPEG-4. As a
result, you'll probably need to up-convert your MPEG videos to
standard AVI or DV formats before you edit them. You really
only can use the lower-resolution and lower-rate MPEG-4 clips
for streaming or video in a window.
The
Panasonic D-snap SV-AV100 SD video camera clearly breaks new
ground in fitting a camcorder into a shirt-pocket form factor.
It's a great solution for capturing quick, short clips,
especially because its portable size means it's more likely
that you will have it along with you in the first place.
Because
of the limitations of the SD memory size, you do need to be
conscious of the trade-offs with the video resolution and
quality. After up-converting to edit with other footage, even
the "Fine" quality MPEG-2 clips will be visibly
lower quality. But the other formats should work well for
streaming and other computer applications of video in a
window. Pretty impressive for a bar of soap!
Buy the Panasonic
SVAV100 D-Snap . from Amazon
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