How to Edit and Play HD
Video on the Desktop: HDV
and AVCHD
The Guide to Consumer Software for HD
Video Playback &
Editing
by Douglas Dixon
www.manifest-tech.com
High-definition video is
here -- not just for broadcast television
and professional videographers, but now in
under-$1000 consumer camcorders, and
supported by sub-$100 consumer video
software that can run on your desktop.
However, while today's
computers have grown to be able to handle
the demands of standard-definition video,
the advent of HD, like the beginnings of DV,
places heavy demands on a standard computer.
First, HD video is big -- some four times
bigger than standard definition -- so it
takes more storage and bandwidth just to
move clips around. And HD uses new formats
like HDV and AVCHD, which require more
processing power to display (much less edit)
the frames.
As a result, we're back to
the beginnings in some ways -- consumer
software applications are past ten
generations in their development, but again
have to play catch-up with the new formats,
new demands, and new hardware developments
like multi-core processors.
As a result, some
applications, like CyberLink PowerDVD, are
very sensitive to your system configuration,
refusing to even to try to play back HD
clips if they cannot validate your system
and video hardware. Others, like Pinnacle
Studio, are willing to try anyway, even on
an older or lower-power system. After
warning that performance might suffer, it
still tries to play and even edit HD clips,
albeit with some stuttering when the system
runs out of horsepower.
So let's look at the two new
HD formats for playback and editing -- HDV
and AVCHD -- and see some of the issues in
working with them on the newest generation
of consumer video software.
The big question with
bringing high-def video to consumer
computers and camcorders is how to store the
HD frames -- what compression format to use,
and how aggressively to compress so that it
is feasible to store and process all that
data with desktop and handheld equipment. We
can't just use the same old processing for
this much higher resolution -- this is a
major step up in resolution -- from MPEG-2
on DVD and DV on tape at 720 x 480, to HD at
what's called 720p (1280 x 720) and full
1080i (1920 x 1080).
Instead, we need new
compression approaches to still be able to
fit a reasonable amount of HD video on a
consumer devices and storage media -- tape
cassettes, DVD discs and mini-DVDs on
camcorders, small hard disks on camcorders,
or even multi-gigabyte solid-state memory
cards. The developers of the new high-def
disc formats, Blu-ray Disc and HD DVD, were
faced with a similar problem -- even with
higher-capacity optical discs (15 to 50 GB
double-sided) they needed to fit several
hours of a high-def movie, plus sound
tracks, plus special features.
The result of these needs
was convergence on several options for
storing high-def video: HD MPEG-2, WMV HD,
and MPEG-4 AVC / H.264.
- The most direct option is
to scale up MPEG-2 to high-def, since
it's well supported from desktop DVD to
digital television broadcast equipment.
However, this requires significantly more
storage with the increased resolution, and
newer compression approaches like WMV and
H.264 promise the same quality for roughly
have the size.
- Microsoft Windows Media
Video (WMV) is designed to scale
from tiny handheld screens, to Internet
streaming, to full-screen TV, to widescreen
HD, and so is an especially good option for
delivering HD for desktop playback.
- The enhanced MPEG-4,
called both AVC (Advanced Video
Codec) and H.264, is similarly
improved and scalable, and is often used for
mobile phones and handheld video devices
like the Apple iPod.
All three of these HD video
formats were adopted as options for both of
the competing high-def disc formats. And
they were also used as the basis of new
industry formats for HD video in consumer
products, using specific variants of
MPEG-2 HD (called HDV) and
MPEG-4 H.264 (AVCHD) adapted for
use in consumer devices, especially small
handheld camcorders.
The HDV format was
developed by Canon, Sharp, Sony, and JVC in
2003 to fit HD video into the capacity of
standard DV media (DV or Mini DV cassette
tape), allowing DV-like camcorders to shoot
in high-def, and then deliver it to a
computer with the same workflow as DV, over
USB or FireWire / IEEE 1394 interfaces (www.hdv-info.org).
This required several
adaptations to squeeze the HD video to fit
into the same tape that is used to store an
hour of standard-def DV video. To start, DV
is a relatively lightly compressed format,
in which each frame is compressed
independently, which makes it very
convenient for editing. MPEG-2 compresses
harder using inter-frame compression, in
which frames are compressed in relation to
each other, storing only the differences
between adjacent frames. This provides
better compression (i.e., from DV on tape at
25 Mbps data rate to MPEG-2 on DVD at 9 to 6
Mbps), but is more difficult to edit since
each frame can only be decompressed and
processed in relation to the group of frames
adjacent to it.
The next step for HDV is to
compress more aggressively, using a longer
group of pictures (GOP) of adjacent frames
--- which means even more work when editing.
And the final trick with HDV for the higher
HD resolution is to not store the full 1080i
resolution (1920 x 1080), but instead give
up some horizontal resolution and use 1440 x
1080.
The HDV video format, then,
supports MPEG-2 compressed video, at
two widescreen 16:9 resolutions:
- 720p (1280 x 720,
progressive), at 19 Mbps (less than DV!)
- 1080i (1440 x 1080, interlaced), at 25
Mbps (same as DV)
at both NTSC and
PAL television rates (30 and 25 frames
per second):
- 720p at 60p, 30p, 50p,
25p
- 1080i at 60i, 50i
For audio, HDV supports
MPEG-1 Audio Layer II compression at 48
kHz sample rate, with 16-bit samples, stereo
(2-channel) at 384 kbps data rate.
The result is a nice
compromise, fitting HD video into the
existing DV workflow -- with the same tape
capacity, and the same data rates --
although requiring significantly more
processing, not only for decompressing the
larger frames, but for dealing with the
larger groups of adjacent frames that need
to be processed together.
Another issue for playback
and editing on computers is that the HDV
file format is optimized for capture on
consumer devices, and uses the MPEG-2-TS
(Transport Stream) format designed for
transmission, and not for data file storage
and processing. Unfortunately, not all video
software can deal directly with this format,
since they expect the common MPEG computer
file formats: program streams (typically
.MPG, with mixed video and audio) and
elementary streams (typically .M2V, with
just the video data, plus separate audio
.WAV files). Instead, there's now video in
transport stream files with names like .M2T,
.MTS, and even .M2TS.
A further confusion is that
consumer HD camcorders are no longer just
tape-based -- the data may be stored on
mini-DVD or hard disk or memory cards. As a
result, video editing software that was
designed to "capture" video (importing it
over USB or FireWire from a video camera),
now also needs to be able to handle opening
the files directly, i.e., after they have
been copied directly to hard disk.
As HDV was originally
designed to fit high-def video on DV tapes,
AVCHD was designed by Sony and
Panasonic to fit HD on mini (8cm) DVD media
(www.avchd-info.org).
Since the format was
developed later,in 2006, instead of using
MPEG-2 compression, AVCHD uses MPEG-4
H.264, also called AVC. As a newer and
more advanced format, AVC can provide
similar video quality for less storage and
bandwidth.
Like HDV, AVCHD supports
multiple video resolutions:
- HD at 1920/1440
x 1080 and 1280 x 720 -- 16:9
- SD at 720 x 480/576 (NTSC/PAL)
-- 4:3 or 16:9
And it supports multiple
frame rates, for NTSC, PAL,
and film:
- 1080/60i, 50i, 24p
- 720/60p, 50p, 24p
For audio, AVCHD supports
two formats, including multi-channel
surround sound:
- Dolby Digital
(AC-3), 64 - 640 kbps, 1-5.1 channels
- Linear PCM, 1.5 Mbps (2
channels), 1-7.1 channels
Since AVC is one of the
formats used for Blu-ray high-def discs,
AVCHD could be designed so that discs
recorded on a consumer DVD camcorder could
be played directly on a Blue-ray set-top
player. The result, however is a messy
folder structure similar to what you also
find on today's digital still cameras that
shoot both still photos and video clips.
For example, the
Panasonic HDC-SD1 and -SD5
tapeless AVCHD camcorders with Leica lenses
and 3 CCD sensors record HD video direct to
SD / SDHC memory cards (www.panasonic.com).
Since there's not tape or disc drive
mechanism, they can be designed to about the
size and shape of a soda can: a big lens
plus some associated electronics.
The older SD1 records at
1440 x 1080 video with Dolby AC3 5.1 sound,
and the new SD5 records at full HD 1920 x
1080 with stereo audio -- at a size of only
2.6 x 2.6 x 5.3 inches and 3/4 pounds.
Find the
Panasonic HDC-DX1 DVD camcorder
and
Panasonic HDC-SD1 memory card
camcorder on Amazon.com
The Panasonic AVCHD camcorders use the
following file structure:
DCIM\
Photos
100CDPFP\
IMGAnnnn.JPG JPEG
photos, i.e. 1920 x 1080
MISC\
AUTPRINT.MRK
PRIVATE\
AVCHD\ Video
AVCHDTN\
THUMB.TID
THUMB.TDT
BDMV\
Video clips
INDEX.BDM
MOVIEOBJ.BDM
CLIPINF\
nnnnn.CPI
PLAYLIST\
nnnnn.MPL
STREAM\
nnnnn.MTS Video clips
(MPEG Transport Stream), 1440/1920 x 1080
In this disc-based format,
each video segment that you shoot is stored
as a separate .MTS file, numbered
consecutively in the same way a digital
camera stores each photo. The camera than
can easily display a thumbnail index of all
the clips for you to review and play back.
However, since the AVCHD
format is newer than HDV, the latest
versions of consumer video player and video
editing software are just starting to
support it. Some can import the individual
video files, and some can import the entire
disc folder structure (i.e., under the AVCHD
directory) like a DVD, allowing you to
quickly choose the clips that you ant to use
in your project.
Unfortunately, there are two
"flavors" of AVCHD, from Panasonic and Sony,
so, for example, Sony Vegas Movie Studio
only supported the Sony version. This is
representative of a more general problem
with all these video formats -- there is so
much variety possible even within one
specific format that it's not uncommon to
find cases of apparently similar files where
one will play fine while the other has
problems. Expect to always need to check and
test new files from different camcorders or
different software tools to make sure they
work as needed.
The first step with HD video
is just to play it back and view it on a
computer. Both the consumer DVD player
applications for Windows -- CyberLink
PowerDVD and InterVideo WinDVD --
can play a wide variety of video and audio
formats, including versions of MPEG-2 and
MPEG-4, and Windows Media Video, including
WMV HD. But not all of today's software can
handle the MPEG formats embedded in a
transport stream file, or some of the HD
variants.
Some of these applications
recognize the .M2T / .MTS MPEG transport
stream file types by default, or can open
them if you explicitly import them. As a
work-around, some can import the files if
they are renamed to .MPG.
Most of today's software can
handle HDV, since it's been out for a while,
and the latest versions have been adding
support for AVCHD, also as an outgrowth of
their expansion to cover MPEG-4 formats and
high-definition discs.
Today's software also is
optimized for playback on multi-core CPUs,
so on my quad-core 2.66 GHZ MHz test system,
I saw playback using around 25% of the CPU,
and spread across all four core processors.
Since the Microsoft
Windows Media Player is built on top of
the Windows media architecture, it can take
advantage of new codec components
(encode/decode modules) that are installed
with new player and editing software, and
also play these new formats (www.microsoft.com/windows/windowsmedia).
Meanwhile, Apple's
QuickTime Player has been leading in the
playback of the new MPEG-4 formats,
especially for clips from mobile phones and
portable devices (free,
www.apple.com/quicktime). However, in my
testing with Windows version 7.2 it did not
play sample HDV and AVCHD transport stream
files.
CyberLink PowerDVD Ultra
(version 7.2) did a great job of playing my
sample HDV and AVCHD files ($99,
www.gocyberlink.com). It provided full
controls during playback -- with responsive
single step forward and back, dragging the
slider to scan forward and reverse, or
clicking to jump to a new point.
PowerDVD did not recognize
M2V AVCHD files, but would open them when
they were renamed to MPG. It also could open
the AVCHD folders as a disc, playing though
the numbered collection of .MTS clip files
like a DVD (or actually Blu-ray) disc, with
each clip as a new title.
InterVideo (now Corel)
WinDVD 8 could play HDV .H2T files after
renaming them to .MPG, but was slow in
jumping within the file ($59,
www.intervideo.com). It also could play
individual AVCHD files, but not open the
full folder structure. Unfortunately, WinDVD
did not display the slider control to seek
back and forward in the file, so you could
play and pause, but not single step or skip
around.
Similarly, the latest
versions of consumer editing applications
typically support working with HDV, and are
starting to support AVCHD. Most can import
directly from popular camcorders, and some
can open files that have been copied to a
hard disk.
Apple iMovie '08
supports standard and high definition video,
including DV, HDV, MPEG-2, MPEG-4, and now
AVCHD ($79,
www.apple.com/imovie). However, Apple
currently lists only a few AVCHD camcorders
as tested and supported: the Sony HDR-SR1
and SR7 (hard disk) and Panasonic HDC-SD1
(memory). AVCHD DVD camcorders are not
supported. AVCHD support also requires an
Intel-based Mac.
(iMovie '08 Camcorder
Support -
http://docs.info.apple.com/article.html?artnum=306171)
Pinnacle Studio 11 Plus
version provides an end-to-end HD video
editing workflow, including native HDV and
AVCHD editing ($99,
www.pinnaclesys.com). It is designed to
import from HDV camcorders, but could not
process the .M2T files directly. It did the
best job of working with AVCHD videos on my
system -- opening, playing, editing, and
exporting with good response.
Studio could browse quickly
though the AVCHD folder structure, view
thumbnails of the clip files, and then click
to preview the clips. The interface was very
responsive, dragging the slider to scan
though the clip, playing fast forward and
reverse modes at 2, 4, and 10X speeds, and
even resizing the application window while
playing video. It also has a handy
full-screen playback mode.
Ulead (now Corel)
VideoStudio 11 Plus version supports HD
formats including AVCHD and MPEG-2 HD ($129
www.ulead.com/vs). It opened and edited
HDV video clips, including .M2T, with a nice
Info window to show clip properties. While
it did not open individual AVCHD files, it
could import clips from a folder, displaying
an Import DVD dialog listing the clips, and
to preview and select the ones to import
into your project.
However, VideoStudio was
sluggish when dealing with AVCHD files --
taking seconds to switch between the editing
steps, or to display a new frame when you
drag the slider to a new position (it could
not scan though the video).
Sony Vegas Movie
Studio+DVD 8 Platinum Edition supports
HD video, including HDV capture and editing
($119,
www.sonycreativesoftware.com). It also
supports AVCHD import and edit, but only
from Sony camcorders, so it refused to
import my Panasonic files. Sony says support
for Panasonic AVCHD is in the works.
CyberLink PowerDirector 6
supports high-definition video editing, with
the HDV format for capture, editing, and
export back to tape if desired ($89,
www.gocyberlink.com). AVCHD support
should be coming in the next release.
Nero Vision 4
supports HDV and AVCHD editing (part of the
Nero 7 Ultra Edition Enhanced suite, $79,
www.nero.com/nero7). It processed HDV
files after renaming to .MPG, and played and
scanned though AVCHD files.
The bottom line is that you
can use $100 consumer software to work with
HD formats -- but make sure you have the new
versions, and check for the latest updates.
The developers are still working to catch up
to the new formats (like AVCHD), and to new
ways of accessing formats (as with HDV in
.M2T files).
I've explained how these
applications worked for me when I tested the
versions available at the time. However, the
software that works best for you will depend
on your specific HD camcorders, and sources
for HD video files. So check the websites
for new releases and updates, and for trial
versions that you can download to experiment
with how they work with your clips and
perform on your system.
References
HDV Format
www.hdv-info.org
AVCHD Information
www.avchd-info.org
CyberLink - PowerDVD Ultra
www.gocyberlink.com
InterVideo - WinDVD 8
www.intervideo.com
Apple - iMovie '08
www.apple.com/imovie
Pinnacle Systems - Studio 11
www.pinnaclesys.com
Ulead - VideoStudio 11
www.ulead.com/vs
Sony - Vegas Movie
Studio+DVD 8
www.sonycreativesoftware.com
CyberLink - PowerDirector 6
www.gocyberlink.com
Nero - Nero 7 Ultra Edition
Enhanced / Nero Vision 4
www.nero.com/nero7
Manifest
Technology®
Copyright 1999-2008,
Douglas Dixon, All Rights Reserved
Manifest Technology is a registered
trademark of Douglas Dixon
