WWDC2004 Session 702

Transcript

Kind: captions
Language: en
welcome to an overview of quicktime
codecs session 702 my name is Dennis
Backus i'm a senior technical manager in
the marketing group that apple and it's
my very very distinct pleasure to
introduce from ursa major media I got it
right cliff and meter cliffs been in the
QuickTime business for how many years in
minutes now 15 minutes yeah we pulled
him off the street you know no I saw
always on ears he also runs a really
interesting sighs you guys haven't seen
that you should go take a look at it's
called quick timing gorg it's a it's a
very good dissipation site for all
things quicktime of both third-party
products apple announcements and all
sorts of things that you never never
heard of but need to use so that further
videos we bring clifford onda onstage
question and answer we want to hold to
the very end and we want to make sure to
use the microphones so that we can pick
this up for the recording ok thanks
that's so will like it applause I have
anything done anything yet I love that
ok so I'm going to talk a little bit to
you about quicktime codecs and try to
get through i'll give you a little bit
of information kind of an overview of
the different quicktime codecs are avail
that are available what they're good for
what you might want to use them for in
production environment which ones are
not really all that useful you probably
want to skip over as y'all might know
quicktime supports about 200 different
media types sometimes that can make it a
little bit confusing as a technology
because out of 200 media types you often
faced with the question of ok 200 yeah
but which one do I need for what I'm
doing today so we're going to try and
and cover some of that like I said and
argue with enough information so that
the next project that comes up you'll be
able to at least ask some intelligent
questions
so what I want to cover specifically
criteria for choosing a cadet categories
and types of codec strengths and
weaknesses of different types of codecs
where you might want to use them like I
said and also give you some resources
where you can learn more so I'm not
going to put a lot of time and effort in
the beginning of this talking about
exactly how codecs work or exactly what
they do i do want to cover it just a
little bit of information on codecs in
general basically we use codecs for
three reasons save space and transfer
time save bandwidth or save processor
cycles get them to play on older slower
machines if you're looking at
uncompressed ntsc video you're talking
about 30 frames a second at two fields
per second or 60 images at 640 480 or 27
mega bytes of information passing
through if you've got a brand new dual
processor g5 you might be able to get
playback from that but specifically on
on older machines or if you're
transmitting video want to transmit
video over the web or put it on a CD ROM
that's going to be problematic the DV
codec which compresses to about 5 1
compression is kind of my example here
just to kind of work the man so if we're
looking at 27 megabytes per second
transfer with uncompressed video we're
looking at about 3.5 megabytes per
second or about 30,000 kilobits per
second with DV which is probably the
codec that y'all are most familiar with
because it's what every digital video
camera out there uses essentially you've
got two types of compression I tend to
break things down this way a lot you're
going to hear me say there's two types
of this two types that quite a bit for
some reason it just works out that way
so with video compressors image
compressors audio are specifically with
video compressors and image compressors
you've got spatial compression and
temporal compression spatial compression
is what's used for most codecs that
you'd be familiar with for images like
jpg and ping and Jeff where it's
essentially either finding a way to copy
the same information more efficiently or
it's throwing out some information so
that it stores it in a smaller format
temporal compression is compression over
time hence the stopwatch get the
metaphor it's so an example of spatial
compression typically when you write an
image in an uncompressed format in some
manner you're recording the information
as individual data blocks for individual
pixels in that image so in other words
the pixel width coordinate x equals 0
and y equals 0 is black and what happens
with uncompressed data is that amount of
information is stored for every single
individual pixel it's a little bit as if
in your on your palm pilot you wrote out
Monday 1230 lunch Tuesday 1230 lunch
Wednesday 1230 lunch etc etc etc so what
the compressor does is it finds a more
efficient way of writing that
information it essentially says monday
through friday 1230 lunch so it's
getting rid of information without
getting rid of data does that make sense
everybody good
I like to see the nodding not too shaky
jpg that my two examples here at TIFF
and JPEG TIFF is essentially a lossless
compression so it finds an efficient way
of writing that information without
actually throwing out any of the
important data you don't lose any of the
image jpg is a lossy compressor so it
does throw out some information it
starts out at higher levels of
compression throwing out information
that's theoretically beyond human
perception so colors that we can't see
bits of detail that that are
mathematically able to be generated but
can't really be perceived by people as
you squeeze it further and further down
it begins to thrill out more and more
important information so it in effect it
degrades the image you're sacrificing
image quality to recover some size so
here's an example of the same image
compressed at three different levels
with JPEG if you look really carefully
right in here and right in here and in
the table here this is the least amount
of compression or the most depending on
how you want to look at it so it's it's
the most image information the least
amount of compression so you don't see a
lot of artifacting you don't see a lot
of little sort of schmutz technical term
should write that one down when you look
at this one this is the highest
compression you can start right in here
particularly they see some artifacting
in other words jpg is averaging
information across a group of pixels so
that it can store that in store the
resulting information in a smaller
format and then this is medium
compression which is still pretty decent
quality but just in a few areas
particularly in the stained glass in
here and like right around in here you
can
to see some artifacting so temporal
compression is what we typically use for
video and really good codecs mpeg-4
Sorenson use a combination of spatial
compression and temporal compression in
other words the temporarily compressed
frames you're throwing out more data the
codec is examining the video and trying
to get just the information that's
changed so from frame 1 to frame to the
second frame it's trying to store just
the difference between those two things
and in fact those that second kind of
frame we call a delta frame or a
difference frame then every once in a
while it sets a keyframe which is the
nice pristine temporarily compressed
image spatially compressed image sorry
so here's an example with sinopec
compression Sinha pack is kind of an old
codec but it it shows the differences
off really nice here's the key frame
which has a fair amount of detail even
though it's obviously it's being blown
up quite a bit here and you're getting a
lot of jaggies and then here's the delta
frame or a difference frame so you can
see it's not storing the same amount of
detail at all much more detail over here
much less here and in large part we get
away with that because video moves so we
don't always have to be presenting the
same level of information to the viewer
because it sticks in their brain they
don't see the fact that we're degrading
from one image to the next so here are
the video rules of reduction there's
three ways to reduce file size end or
bandwidth requirements for piece of
video you can reduce the data rate that
is increase the compression
can reduce the physical size of the
image reduce the number of pixels so
instead of 640 by 480 we do 240 by
whatever you reduce the size you reduce
the requirements or you can reduce the
frame rate reduce the number of images
that you're storing in that video all of
those things allow us to deliver video
through a narrower pipe so these are the
things that I looked at if you if you go
to quick timing org go to the resources
section you'll find a little place that
I call codex central partly as an homage
to the old Terran codex central and in
codex central I did a comparison of
basically every codec I could get my
hands on so I sat down and I figured out
exactly what it is I want to compare and
what my standards were going to be for
comparing one code app to another and
pretty much in this presentation I'm
going to use those same standards and
what I look at is quality sighs
compatibility and usability so for
compatibility specifically I looked at a
couple of different things one is how
old a version of quicktime will play it
can you play this codec in quicktime too
can you play it in quicktime 5 and above
i also looked at compatibility
cross-platform does it work on windows
does it work on max doesn't work on
linux and i also looked at compatibility
with other players besides quicktime
okay it's math i'm not going to spend a
lot of time on this this is sorensen's
formula for kind of helping you figure
out what data rates you want to shoot
for forgiving audience okay and the idea
here is you want to look at
coming up with a number based on this
formula once you've come up with that
number you're usually your best quality
is going to be at no more than half that
number and you probably aren't going to
have to go to more than twice that
number now I'll be honest with you from
what I've seen so far of h.264 this may
all be kind of irrelevant okay so that's
that two types thing again there's two
types of video codecs transfer codecs
and delivery codecs transfer codecs are
used to move video from one location to
another generally within a production
environment so a transfer codec I used
to work for a video effects house on LA
and generally we used animation best
which is a lossless codec at when you're
at that level at best and that allowed
us to get smaller file sizes reduce our
transfer times over the network pixel it
is another example of a transfer codec
it doesn't give you the kinds of file
sizes that you're going to need to be
able to deliver say over the Internet to
deliver web video but it is going to
give you minimally lossy or lossless
quality now the other thing is delivery
codecs delivery codecs are going to give
you just a whole heck of a lot more
compression but aren't going to throw
out some information that you're going
to sacrifice quality to get playability
so the first thing we're going to look
at is delivery codecs now with delivery
codecs with I'm sorry I was distracted
by the shiny thing at my feet with
delivery codecs you're typically going
to see compression rates somewhere up
into the ninety percent so if you have a
one megabyte file or let's say you have
a 1 gigabyte file with a ninety percent
that even 99% compression you're talking
about being able to compress it down to
a few megabytes so some of these things
changed yesterday so so I was in the
room last night making a few little
changes the first thing we're going to
look at is the current mpeg-4 in
quicktime which is for simplicity's sake
if you'll pardon the pun the best way to
refer to it I found so far is mpeg-4
simple because it's based on the
advanced simple profile good quality
it's currently it's somewhat limited by
the current mpeg-4 spec the mpeg-4
simple has been around for a long time
how many people have ever seen MPEG
three yeah see nobody's seen MPEG three
it didn't exist because nobody could
agree on what the heck it was so they
skipped over from mpeg-2 mpeg-4 and it
took them a long time to come up with
mpeg-4 and by the time everybody got
their ducks in a row on it it had
already been suppressed surpassed by
some more modern codecs like Sorenson
three so the quality is okay good we're
going to look at 264 here in a second
which completely blows it away the size
is good the compatibility is excellent
works in quicktime works in real there's
a ton of third-party players out there
and it's been around since the
introduction of QuickTime six so which
has been a while now and it's a good
general purpose codec
h.264 or a vc it which is advanced video
codec quick overview here excellent
excellent excellent excellent we're not
going to see it for a while so we're
going to talk about some of the other
codecs as well and I'm in the same boat
that the rest of y'all are in I'm going
to go home and I'm going to play around
with it and see what I get but again
from everything I've seen so far this is
going to be the way to go for most
general purpose encoding come early next
year sorensen video 3 is my current
favorite general-purpose codec it's
higher quality than mpeg-4 at about the
same file size it can get a little bit
bigger than mpeg-4 it takes slightly
longer to encode but I actually started
out as an illustrator so I'm something
of an image snob if for pure quality if
I'm looking to go with something that's
just got to be pretty I always fall back
to sv3 quality is excellent the size is
good compatibility is good and the
usability is good now notice my little
footnote down there we'd be having a
different discussion a year from now now
Sorensen also has an impact for Kodak
that is slightly different from Apple's
mpeg-4 codec encoder and that's included
with sorenson squeeze sweet you get
mpeg-4 you get sv3 and you get the spark
codec which is for flash which kind of
sucks but you know you gotta take the
bad with the good
good good excellent good again it's
based on the mpeg-4 spec its ISO
compliant so anything that plays mpeg-4
is going to play the Sorensen codec as
well usability is good it's still
limited by the mpeg-4 simple profile it
it doesn't have the level of quality
that you're going to see with some
proprietary codecs and it doesn't have
the level of quality that h.264 is going
to bring us soon in a few months 3i VX
is at this point my favorite mpeg-4
variant by the way just so everyone
knows all opinions expressed during this
presentation or our mind so it's very
good quality gives you excellent size
the compatibility is excellent it's
right now already works for a number of
set-top boxes a number of players it's
very widespread on the Windows platform
and i think i think the usability is is
excellent because of all those reasons
h.263 is mostly kind of irrelevant at
this point but i wanted to touch on most
of what you see when you pop up that
little export menu in quicktime pro it
marginal quality good size very good
compatibility it's been around for a
long time but I still find the usability
is poor now that said there are
instances where I will fall back to
h.263 because it has very low processor
overhead so I've used it to do things
like I built a video puzzle for a client
where you actually can grab pieces of
the video and move them around and all
the video is moving on all the pieces
all at the same time
now if I try to do that with sv3 on
anything made before the last two years
it would choke and die but with it with
h.263 it it was light enough that it
actually worked and in that particular
instance quality was not paramount
playability was Zygo video is another
cadet that I like a whole lot it's a
third-party codec from zygo digital I
think they just changed their name it's
the codec I generally go to these days
if I'm doing live streams it's again
quality is good and high data rates it's
clearly inferior to sv3 and mpeg-4
either apples or sorensen's but at very
low data rate it really starts to pull
ahead of just about everything else
that's out there and when you're doing
encoding for streaming you don't have
the luxury of the kind of spikes that
you get day rate spikes that you get
with something like sv3 you need
something that's going to give you well
you know that's just going to get it
there so compatibility is fair it's it's
not part of the QuickTime delivery when
you install quicktime it's something
that people will have to go and get and
download to be able to look at your
video and i always think of that as a
disadvantage but i've used it in a
couple of places where i have clients
who are delivering real streams inside
the enterprise and I essentially have
control over what goes on all the
machines within the enterprise so I can
say this has to be installed on
everybody's machine for them to watch
the president's talk
goodness okay side-by-side comparison
okay I worked hard on this ah-me noises
geez I know you're out there I can hear
you breathing okay so this is 3 ivx this
piece is Apple's MPEG simple code at and
this is the sp3 code app so you can
clearly see that there's a little bit of
quality difference between the three I
actually tried to get it so that the
quality was about the same because this
is this is what I really wanted to show
you this even with when the quality is
the same the math is not three ivx I got
a file size of 428 kilobytes at a data
rate of 105 with apples MPEG I got a
file size of one megabyte and a data
rate of 254 now there's not a tremendous
difference in quality between those two
things is there but I'm getting a much
more deliverable file size with this and
then even sp3 in this particular
instance came out a little bit of a
little bit ahead so on the encode side
though Apple's mpeg-4 had the fastest
encode time sv3 had the slowest and
three ivx came out somewhere in the
middle these are by the way my three
choices if you're doing web video or
cd-rom I nearly always go with one of
these three three ivx has the
disadvantage again that they're going to
have to go and get it and download it or
you're going to have to include it in an
installer on on a CD if you're
distributing that way Apple's mpeg-4 and
sp3 are both part of the current
quicktime distribution transfer codex
as I said transfer codex exists so that
we can compress a little bit retain the
information and move things more easily
from one place to another hence the
transfer so DV I've got like six slides
worth of DV there's it's like it's like
they're all like they're all Baptists
but some of them are Southern Baptists
and some of them are like you know
evangelical and there's a few
Pentecostal you know they're all over
the place so DV comes in line or to put
it another way Vivi comes in multiple
flavors in QuickTime and some of these
are are more for the pro apps and some
of them are sort of the standard DVD
that you're seeing when you buy it go
out and buy a camera I'm really going to
kind of blow through these a little bit
quickly but want to give you a little
bit of a little bit of an idea DV NTSC
and PAL qualities good sizes fair
compatibilities excellent usability is
good dvcpro and about to say about the
same ok so if we worked our way past DV
and now we're to my current favorite
transfer codec which is animation and as
I was mentioning before back when I
worked in a visual effects company
animation is what we typically use to
move things from one machine to another
or make a file small enough a scene file
small enough that we could write it to a
CD and deliver it to a client or do
something like that and one hundred
percent animation is lossless it may
also not do a whole heck of a lot of
compressing for you because it was
really designed to work primarily with
large flat areas of color and with large
flat areas of color you can get really
phenomenal levels of compression but if
you're looking at
standard video at best you're only going
to get about fifty percent now that's
not so bad fifty percent is about what
you can expect from most lossless codecs
animation also has the advantage that it
supports somewhere here might not be
there anyway has the advantage that it
supports transparency so it supports
alpha channels so if you're working in
after effects or something like that
it's a good codec to work in it's going
to save you a little bit of drive space
and it's going to allow you to work with
alpha channels and in general just about
any professional video editing
application is going to support
animation pixel it picks looks new how
many of you you guys have had a chance
to play around with a little bit pixel
it does a really really good job as a
transfer codec it is lossy not lossless
so you are going to give up some data it
making it a real good archive codec but
you don't want to be opening files and
receiving them over and over again
because you going to continue to throw
stuff away good size you can get a six
gigabyte file down at near DVD quality
down about 250 megabytes that's pretty
decent savings if you're hurting for
hard drive space it's a real good way to
go I listed the compatibility is poor
though right now it really only works
you know less 10 and that's kind of
limited as I say usability is limited
sheer video is a third-party codec that
I also liked very much as a transfer
kodak it is completely lossless and
preserves the image perfectly
it's only going to give you about 2 to 1
compression it's os10 only in general I
would try animation best first and use
pixel it as a fallback unless you happen
to work in a studio that is all OS 10 G
finds this is the best way to save and
transfer video if you can afford it
Apple none is none no compression it's
completely uncompressed format it's
going to take up one heck of a lot of
drive space but if you're pulling it
into other applications like after
effects or Final Cut or something like
that to work on it and you're likely to
have to be moving files around and
chopping them up and saving them in
multiple times and you've got the room
that's the best way to move things
around otherwise go with animation best
as your first try and then go to
something like share video or pics lit
as your second pass if animation isn't
giving you the the kind of compression
that you need so other codecs there are
a bunch of other video codecs digital an
hour cream makes one called microcosm
which is a 64-bit lossless codec the
last time I looked the only thing that
really supported 64-bit video was after
effects I think six so that makes it
poor and the compatibility front digit
Lanica also makes something called none
16 which again is a 64-bit lossless no
compression codec techsmith makes a
codec called in sharpen which was really
designed for doing screen captures it
deals with detailed things like text
extremely well again excellent quality
good size poor compatibility it's not
part of the standard quicktime
distribution it's not part of the Apple
component download program they have to
know where it is they have to go they
have to hunt it out they've got to
download it if they want to use it and
then there's a whole bunch of legacy
codex of which the only one that's
really notable at all i think is Sinopec
and that's only because sinopec has made
something of a comeback in the last year
or so as the compressor of choice for
the kinoma player which allows you to
playback movies on palm devices audio
codecs it's at two kinds of thing thing
again there's two kinds of audio coccyx
I am used myself sorry let me go back to
second basically the human ear is more
sensitive to slight variations when
you're listening to things like music
and sound effects then you are when
you're listening to things like the
human voice so there's really two kinds
of codecs for dealing with audio their
codecs that are really good at
compressing sounds like music like sound
effects etc etc and their codecs that
are really good at compressing voice and
as long as you don't get these two
things confused you'll do fine when I
looked at these codecs that we're about
to go through in terms of usability
compatibility etc you'll often see that
what I'm saying is for what they're
designed for their excellent but if you
try to use a Kodak that was designed for
dealing with a voice to compress
something like music or sound effects
you're not going to get a pleasant
sounding result and if you try to use a
that was designed more to handle music
and general compression you're not going
to get as much compression so again I'm
going to skip over a little bit of the
detail but basically music and audio CDs
use AIF it's an uncompressed sample they
sample the audio 44100 have a data rate
of about 150 so one minute of
uncompressed audio is about 11 megabytes
of storage and that's why on your 650
700 megabytes ed you don't get 100 songs
so again with the rules of reduction
there are three ways strangely enough to
reduce the size and bandwidth
requirements for audio you can reduce
the sample rate in other words if you go
down from 44.1 to 22 or to 11 you're
reducing the sample rate you're reducing
the size of the audio you can reduce the
range of the sound which you know it's
flattened out the highs and lows or you
can shorten the clips duration now you
see really you think about these they
equate on an almost one-to-one basis
with how video codecs rules of
reductions work ok this is the same as
reducing the image size this is the same
as as increasing the compression and
this is the same as reducing the frame
rate ok audio codecs mp3 mp3 bugs me I
have this whole thing about language and
and the misuse of it mpeg1 layer 3 audio
it's it's not MPEG 3 it's mpeg-1 which
is actually getting kind of long in the
tooth at this point and probably should
be put out to pasture
quality is good I don't think it does
very well below 120 8 kilohertz so size
is good a whole lot smaller than AIF or
WAV files compatibility is excellent you
can't fault mp3 for compatibility I
think they're they're probably shoes at
this point that will play back mp3 files
if not I'm sure having said that
somebody will have one on the market
sometime the next couple of weeks so and
the years ability overall is good you
got to be willing to sacrifice a little
size and flavor plate in favor of
playability but it does have its
advantages however this is my current
favorite audio codec the AAC codec which
you'll notice by the way is excellent
excellent excellent and say it with me
now okay good okay so 128 k now remember
i said mp3 is below 128k most people
don't think it sounds all that well 128k
stereo has been judged indistinguishable
from the uncompressed source and this is
by i don't know a whole bunch people are
supposed to know this stuff you know I
audiophiles much smaller files with mp3
at much higher quality cross-platform
cross player and cross device
compatibility is what the mpeg-4 spec is
all about AAC has pretty widespread
support at this point even if you ignore
iTunes and the ipod and God knows it's
awful hard to do that these days so and
you know flat out it's quite possibly
the only audio codec you're really going
to need to use it is a terrific
general-purpose codec does a nice job
with voice does a fantastic job with
music and sound effects
I haven't had a chance to play a whole
lot yet with the Apple Lossless encoder
which is relatively new I think it came
out in 651 is it writing something like
that okay anyway it's new and the
quality is excellent I mean you can't
beat lossless las luces well lossless
the size is good again it's a lossless
encoder you're going to get around fifty
percent something like that
compatibility and that's a good it's
very new you get it to work with iTunes
you can get it to work with 651 not a
whole lot else right now it's a nice
format if you're going to store a whole
bunch of music on your hard drive for
playback in itunes and you want to
squeeze those down and you don't want to
sacrifice any of the quality at all IMA
for one for a long time this is my codec
of choice it was also the codec of
choice for a lot of people who do like
the movie trailers and things like that
it does a terrific job with sound
quality I used to work for Sorenson and
at their Burbank encoding center we did
some tests with it and compressing with
IMA for one we discovered that it even
retained that the five dot 1
surround-sound information doesn't give
you a lot of compression now the size is
only good compatibility is only good
it's been around for a long time but and
it doesn't only it doesn't always give
you what you expect when you move from
one platform to another the usability is
good it's great for high-bandwidth
projects it's what I will generally use
if I'm going to a project on cd-rom and
I know I'm going to be playing back
through a like a computer stereo speaker
system I want something really really
nice
qualcomm pure voice now again you're
going to see my little caveat with this
one in the next slide when used as
intended qualcomm pure voice is you
guessed it a voice compression codec it
was actually designed for use with
telephones does a fantastic job with
speech it really high levels of
compression though it can sound trying
to Tinian flat sounds a little bit like
you're talking into a paper tube you get
this sort of vibrational thing it's kind
of weird the size that was excellent if
you're doing just spoken word I would go
here if you want to get the best
compression to size ratio it going to
compress the crap out of it with this
codec compatibility is good it's been
around with every QuickTime distribution
since version 3 limited tonal range
makes the usefulness for music and sound
effects limited as I said this is an
excellent codec when you apply it to
what it's intended to be used for if you
try to use it for something else you're
not going to get a very pleasant result
okay q design music too is another one
that's been around for a very long time
does a wonderful job with music and
overall I think it's comparable to mp3
in general quality I think AAC beats the
pants off of it but it comes in it comes
in a solid second
other codecs again there are a bunch of
other codecs that you'll see Mace's
legacy codec 16-bit big in little-endian
24 and 30 bit integer and eula and these
are all unless you're doing really
high-end stuff but you know you're an
audio engineer these aren't really going
to be terribly useful to you you la is a
UNIX standard and mesas legacy codec
that's that's completely outclassed by
any any of the more modern codex here's
a little thing here's a little
comparison thank you here's a little
comparison this is aiff uncompressed
audio ok so this is what you hear off
your CD player at home same thing is AAC
22 kilohertz compression 96 kilobits per
second the file size is 212 k backing up
again my photos back up there we go
compared to three point four megabytes
172 okay let's crank it up boys
[Music]
back again come on that we go all right
sex how many people here are substantial
difference between those two things
[Music]
anybody anybody in your musician entry I
think for vast majority of people
they're not going to hear a substantial
difference between those two things but
when you look at the data rate the file
size you see there is a phenomenal
difference between those two things and
that's why AAC is currently my favorite
codec in fact I'll often combine if I
really need good quality I'll combine
sv3 video with AAC encoded audio put
those two things together and you get a
hell of a mix I said hell I still twice
national free time oh okay anyway I note
on image codex I'm not going to go
through all of the veritable cornucopia
of image codecs that are available to
you working in quick time but I did want
to touch on just a couple of them and
give you a little bit of an idea about
what makes these three particular codecs
kind of special I love this codec this
is my favorite image codec I'm crazy
about paying particularly ping in quick
time I do a lot of stuff with wired
sprites and ping is ping is great for
very low overhead stuff it just works
really nicely it's got sophisticated
alpha channel so you can do much nicer
compositing than what you could do with
something like say Jeff and for
for flat total images you're going to
get better compression than you do with
Jeff files in fact about thirty percent
better and for it can't even though it's
a little bit larger than jpeg when you
use it on continuous tone images like
photographs I really like the quality a
lot better and unlike jpg ping is a
lossless compression format so it which
is to say that it compresses similarly
to what jiff does which compresses by
limit salut I'm sorry compresses by
limiting the number of colors in the
color palette that's working with the
image it's supported on every browser
and platform and in quick time since
very early on the usability is excellent
for working with images for working with
particularly with wired sprites and
QuickTime or any kind of image file in
QuickTime ping is my go-to guy I always
use ping even for most of the web work I
do these days I avoid using gifs and
JPEGs and I stick with pain Oh nobody's
even going to go ah ok this is my dog
his name is lorcan coo Kieran it's
Gaelic it means fierce black hound
anything so here's a comparison you may
have noticed I'd like to do these things
so here is ping 224 k with transparency
nice soft anti-aliased lovely lovely
just 64 colors 120k with a diffusion
dizzer and transparency but now look at
the quality difference even though I've
got a larger file here I obviously can
get better compression with Jeff but
when you start looking at the quality
difference particularly the way just
tends to dither jeff has to use dither
to replicate colors that aren't inside
its color palette the quality is so much
nicer look particularly right around
the eye here and right around the eye
here and then this is jpg at best 344
and you get no transparency with it and
it's lossy so if you have to open the
file up edit it again and save it out
again it's putting compression on
compression on compression jpeg 2000 now
is a little bit different thing and jpeg
standard jpg and jpeg2000 are completely
different codecs jpg is at jpeg 2000
excellent quality good size poor
compatibility at this point because not
everybody has has caught on to it yet
there are still better compressors and
in general right now I still think ping
is a little bit better compressor than
jpeg 2000 it's only available in OS 10
on for quick time there is a photoshop
plugin for creating jpeg 2000 files that
are is available from this particular
vendor from lead technologies and this
is a URL for it and you know it'll be
enough it'll be in our home game so so
here's a little bit of a side-by-side
comparison jpeg 2000 uses something
called wavelet compression without
getting into a lot of detail it's just
better this is the Bad Santa so here's
jpg here's jpeg 2000 look right around
the I particularly and how much
artifacting there is jpg JPEG 2000 so
even the detail in the mustache and you
know it's just scary to look at my own
head this large anyway okay so best
all-round codecs and the winners are for
video delivery mpeg-4 and sv3
mpeg4 for compatibility sv3 for slightly
higher quality again a year from now
this will be having a different
conversation h.264 changes the landscape
for audio go with AAC for a general
purpose audio codec it's the best thing
that you have available to you graphics
paying every time and for video and
audio transfer my favorite is still
animation best for most compatibility
and best compression at a lossless level
for more information a couple of sites
being that the self-serving jerk I am I
put mine first so quick timing gorg
which strangely enough is at quick
timing gorg I have news tutorials
reviews all related to quicktime my
ultimate goal is is world domination by
quicktime so lots and lots of stuff on
there i try to cover anything that's
related to quicktime and that's almost
anything that falls into the digital hub
sphere in itunes is quick time I movie
as quicktime Final Cut Pro is quick time
I DVD DVD Studio Pro is perfect time I'm
missing a whole bunch of things here but
you know quick time is the architecture
that runs all of this stuff and in
addition to that i also have a news
section that's updated fairly often
usually about three times a week
sometimes more often if as things are
happening and a newsletter that you can
sign up for that I refer to as my
regular irregular newsletter it kind of
goes out either when I have something
really important to say or when I feel
like it
Martin and I've never actually
pronounced Martin's last name because
I've only met him by email but Martin
has a QuickTime compatibility chart on
his website own he says hi Amy it is a
very very complete listing of all the
quicktime codecs audio image video and
what version of quicktime they were
introduced with really tremendously
useful resource and last but not least I
wrote a book if if you buy it I don't
have to eat my dog anyway quick timers
guide your web video will be out in a
few weeks if you go to books ursa major
media com which is my publishing company
because and be honest I'm a control
freak and you can actually get it at a
discount right now and that's my little
commercial message and this is who to
contact for more information I'm at
cliff at quick timing org fairly easy to
remember and then yellow QuickTime man
at apple com