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Expression® Encoder 3 – Part 1 of 2 Screen Capture
What is it?
Expression Encoder 3 provides the power of industry leading encoding, in a simple approachable interface to make it easy to prepare video for use in a variety of ways, including Silverlight on the Web.

Download Site: http://www.microsoft.com/expression/try-it/

Example Problem(s) it solves:
Encoder has a screen capture application to record from your screen with webcam and microphone support to produce demo and training materials

Usage Notes: Expression Community Home: http://expression.microsoft.com

• AT&T
• CD Networks
• Internap
• Level 3
• Limelight

• Digital Rapids
• Envivio (and press release)
• Grab Networks (formerly Anystream)
• Inlet (and press release)
• Rhozet
• Telestream (and press release)
• VBrick
• Viewcast (and press release)
• Winnov

Which is a huge swath of the professional compression tools market.

DRM service provider support
And we've had a bunch of support for Silverlight DRM powered by PlayReady from DRM service providers. Since Silverlight encryption is applied during content creation, not during content distribution, using DRM has no real impact on the server side; access to a DRM license server to provide licenses to the Silverlight client is the only big difference from a service perspective.

• BuyDRM (press release)
• Entriq
• ExtendMedia 
• Ipercast

• iStreamPlanet

I haven't had a chance to drop by everyone's booth yet, but will be highlighting some of their demos and cool announcements throughout the week when I find out which of the many projects we've been collaborating on are public now.

Silverlight 3: we're 1080p24
So, we had that whole HD on the web discussion a few weeks ago which spun out into many threads on different forums. A few die-hards said that only 720p60 and 1080p24 should count as full HD, based on the original ATSC definition.

It'll keep on being discussed, but that won't keep anyone from calling Silverlight HD, because we've now got 1080p24 working in Silverlight 3. This represents a huge amount of media playback tuning and testing by the Silverlight team, and it's really paid off. Much of the improvements have been since the public Silverlight 3 beta, so those not at NAB will have to take my word for it for the moment, but we're showing off:

• 1920x1080p24 VC-1 at 6 Mbps
• On a Core 2 Duo 2.4 GHz system
• With smooth playback at any size using GPU scaling

And it is glorious.

On the same system we're also showing off H.264 720p24 2.5 Mbps with similarly smooth playback.

While those specs are obviously beyond what many home PCs can do due to screen size or network speed, with Smooth Streaming we can offer that as the highest-end experience while offering further bitrate bands as low as required.

And of course, optimization that enables 1080p on the high end makes 480p work on lower-end machines than Silverlight 2 could support, due to both media pipeline improvemetnts and offloading scaling and compositing to the GPU. The gains on single-core machines are particularly notable; we've got a quite nice Smooth Streaming experience even on NetBooks now.

The public release of Silverlight 3 will be later this year.

New Smooth-Streaming VC-1 implementation
We're working with the encoder tool vendors to integrate a new VC-1 implementation that's specifically tuned for Smooth Streaming. You may recall Expression Encoder's  Smooth Streaming mode uses the VC-1 Encoder SDK in 1-pass CBR mode with a fixed GOP size. While that certainly can produce good video that's Smooth Streaming compliant, in the end that's really the kind of settings used for live broadcasting. With on-demand content, we can do an analysis pass to figure out a variety of better ways to optimize the bitrate. In particular, we can dramatically reduce the incidence of frames compressed to the point where visible blocky artifacts appear.

What it does are awesome in so many ways that it makes my compression nerd soul twinkle with delight. But those details will have to wait for a long and Excel-chart laden blog post of its own.

In the interim, let me offer you a sample encoded in a not-quite-final version of what we're doing here. This is our favorite Big Buck Bunny content, encoded to these specs

• 1080p24 4 Mbps video with a 5 second buffer
• Smooth Streaming compatible VC-1 and WMA 10 Pro
• In a WMV wrapper, so you can play it in WMP

This is what the top end Smooth Streaming bitrate can look like once Silverlight 3 is released later this year. And as mentioned above, we're now doing 6 Mbps on a Core 2 Duo, we've got some further headroom for more challenging content.

Here's the file (hosted by Silverlight Streaming):
http://silverlight.services.live.com/31260/Big%20Buck%20Bunny%201080p24%204%20Mbps%20Smooth%20Streaming/video.wmv

Remember, Windows Media Player can Save As progressive download content without DRM if you want to make a local copy.

If you're here at NAB, Inlet is showing off the new VC-1 implementation as implemented in their Armada product, with a bunch of other output samples. Check it out.

A developer release, not a consumer release

Note that this is a developer release. Silverlight 2 was unique in scope, being the first release with managed code, so we did some consumer events using Beta 2, most notably the NBC Olympics coverage. We’re not planning on doing anything customer-facing with Silverlight 3 until the full release. So this is really a change for developers, designers, and media folks to get a head start on using the new features, and giving us feedback on any issues. End users are welcome to play around with it (I’ve got it installed on my home machines without any issues), but don’t expect to see much stuff on the web taking advantage of it until after it ships.

What’s Available

First off, here’s the Silverlight-specific downloads released today. The official Get Started page is at Silverlight.net.  And Tim Heuer has a great overview of everything.

• Silverlight 3 Tools for Visual Studio
• Expression Blend 3 Preview
• Silverlight 3 SDK CHM File
• Updated Silverlight Toolkit

MPEG-4 (H.264 and AAC-LC) support

First up, as we discussed back at IBC, we’re adding support for MPEG-4 content in Silverlight. Specifically, we’re supporting

• Self-contained .mp4 (including .f4v and .m4a) and .mov file formats (no reference movies or anything fancy like that).
• H.264 video in Simple, Main, and High 4:2:0 profiles (progressive scan only)
• AAC-LC audio mono or stereo (HE AAC will play back with lower fidelity, as in QuickTime)
• Local files or http progressive download.

Or, sliced another way, Silverlight 3 will be able to play pretty much all MPEG-4 files that would play back well in both QuickTime and Flash.

The H.264 and AAC-LC decoders are exposed via the MediaStreamSource used by Smooth Streaming, which means extending support to other file formats and protocols will work there as well. And of course, Smooth Streaming will support H.264 and AAC-LC as well.

Raw AV Pipeline

MediaStreamSource started with the ability to pass off VC-1 and WMA bitstreams to the decoder from managed code, enabling us to add protocol and format support within Silverlight. Most of Smooth Streaming on the client is implemented in C# as MediaStreamSource code. And we’re extending that to H.264 and AAC-LC. But there’s a huge number of other codecs out there that different markets are using and have asked to have in Silverlight. In fact, far more than we can reasonably build and test, and far more than we’d want to have to make everyone download in the installer.

So, instead we added three very simple but very powerful new outputs to MediaStreamSource: YV12, RGBA, and PCM.

Yep, managed code can now output uncompressed video frames and uncompressed audio straight to the media pipeline.

Most video codecs are going to use YV12, which is a flavor of the  a standard Y’CbCr 4:2:0 format used in most video codecs . We also wanted RGBA to enable video with alpha channels, and also any media formats that are natively RGB. And of course PCM is classic uncompressed audio.

Using a managed decoder is transparent to the user; it’s just another managed code .dll included in the .xap file. Since it’s running inside the Silverlight sandbox, there’s no download or other action required by the user to activate it; acts just like any other codec.

So, what’s codec performance like in managed code? It’s actually going to be fine for a variety of tasks. In our internal testing and prototyping, managed code offers about half the speed of a native compiled version. So for older codecs like MPEG-2, a managed decoder should be fine on a wide variety of hardware.

And remember, managed code doesn’t require C#. Existing decoders in C or C++ can be used as the basis for a managed decoder. The main restrictions are that native MMS/SSE and pointers can’t be used.

I can’t wait to see what other kinds of formats and codecs people wind up delivering with the Raw AV Pipeline. We’ve already seen some very neat demos.

GPU scaling and compositing

Silverlight 3 adds GPU support for scaling and compositing. Other products may call this something like “GPU accelerated video playback” which can be a little confusing – this isn’t GPU video decoding ala DXVA. What it does is take bitmap elements, including video, into the pipeline at their native size and then the GPU takes care of scaling each object to its final size, and then doing the final blending and compositing of the whole application. For media players, this essentially gives every player Fast Path performance. So while it does accelerate video playback, it’s not actually accelerating video decode per se. But on single-core machines, anything we can do to save CPU from other tasks to give more to the video decoder, the better. Again, the net effect is lower system requirements for any content that gets scaled; which should often improve the bitrate lower-end machines can play in Smooth Streaming.

There’s a few new facets to tuning a player for GPU playback, so it’ll need to be turned on explicitly in the application. But the performance gains for any video that’s scales are tremendous, so we’re going to help making sure everyone knows how to get it on and reap the benefits.

Full-screen GPU scaling/compositing will be supported on all Macs and all Windows machines with DirectX 9 or higher (which is XP SP1 and higher – that’s most machines and GPUs out in the wild today). Due to platform limitations, Silverlight on Mac won’t support GPU compositing inside the browser window, but will in full-screen mode. For performance-critical players (particularly in HD) a good compromise there is to set Stretch=”None” for the browser version and scale in full-screen mode, so that the windowed version is Fast Path and the full-screen is GPU composited for equivalent performance.

Improved logging

Robust and detailed logging has long been a critical feature for Windows Media to enable advertising and billing.

We’re extending that support to Silverlight 3, for both Windows Media and Smooth Streaming. I’ll provide a link to the full details when they’re posted.

Media pipeline improvements

We’ve done some under-the-hood work in Silverlight to optimize for silky-smooth video playback with as few dropped frames as possible. For the beta, we’ve focused mainly on single and dual-core systems, and you should see some significant improvements with the same player and content in SIlverlight 2 (and of course using the GPU when scaling will offer further performance gains).

Out of Browser Silverlight applications

Silverlight 3 will allow applications to be dragged out of the browser and onto the local system as a standalone, double-clickable app. This is useful for all kinds of applications, of course, but for media players it’s great to not have to launch the browser when all you want is an applet media player. This includes offline support, so a Silverlight media player could be used on an airplane or anywhere else without a network connection. And since it’s a real Silverlight app, it still uses the secure sandbox and so Admin rights on the machine aren’t required to install or run it. We’ve got nice integration for both Mac and Windows with Start Menu and Dock compatibility.  Ashish’s blog has lots of details.

The IIS team has just released the first public beta of the Smooth Streaming module for IIS7. This means anyone with Windows Server 2008 can start experimenting with this next generation media delivery technology for Silverlight. We’re aiming for a final release in Q2 this year, which will be licensed for full commercial use. There’s lots of detailed info in the links before, but let me offer my own high-level take on what Smooth Streaming is about and why it matters.

Smooth Streaming adapts streaming to the web instead of trying to adapt the web to streaming

Alex Zambelli explored this concept in the links below, but I love it so much I’m going to reiterate. Smooth Streaming leverages the massive scale of the standards-based http web delivery technologies, instead of trying to define different protocols or requiring a lot of bidirectional communications. The media itself is sent as a series of small files as http requests, so it gets automatically cached by the proxy servers in CDNs, ISPs, and corporate firewalls. And of course can pass through firewalls easily.

Smooth Streaming streams smoothly

The core user experience we’re shooting for is quick starting, fast scrubbing, uninterrupted playback of content as good as the local machine can play at the moment. We switch between bitrates and resolutions basic on available CPU speed, network speed, and window size without any “buffering” messages as long as there’s sufficient bandwidth to deliver the lowest bitrate.

Smooth Streaming is standards based

Smooth Streaming uses the http protocol and the MPEG-4 file format (in its “fragmented” flavor). We’re initially using VC-1 (SMPTE standard) and WMA 10 Pro audio, and will support H.264 and AAC-LC support once Silverlight 3 ships with those codecs. The manifests use XML and SMIL.

Smooth Streaming can be authored today

Expression Encoder 2 (with Service Pack 1 installed) includes full support for authoring on-demand Smooth Streaming content, including all media files and manifests. The Silverlight 2 templates included with SP1, and the underlying Base Player, support Smooth Streaming. Other compression tools will be adding full Smooth Streaming support in future versions.

All the Links

We’ve gone blog-crazy here at Microsoft. Which means that there’s lots of great information coming out of us these days, so it can be kind of hard to find it all. Here’s my list of good Smooth Streaming references and tutorials.

Official pages

• IIS Smooth Streaming
• IIS Media

The Demo

• SmoothHD.com (our joint demo site with Akamai)

Downloads

Yep, it’s a free beta download for any version of Windows Server 2008. There are free 60-day trial versions of 2008, including a .vhd download.

• Smooth Streaming Beta for 32-bit Windows Server 2008
• Smooth Streaming Beta for 64-bit Windows Server 2008
• Web Platform Installer (single installer for IIS, SQL Server Express, .NET Framework and Visual Web Developer components)
• Trial versions of Windows Server 2008
• Expression Encoder 2 Service Pack 1 (the full Expression Encoder 2 with SP1 installed is needed to author Smooth Streaming content)

Learn IIS7 articles

• Smooth Streaming for IIS 7.0 - Getting Started
• Smooth Streaming for IIS 7.0 - Exploring Bit Rate Changes
• Smooth Streaming for IIS 7.0 - Managing Your Presentations

My Blog

• Expression Encoder 2 Service Pack 1 – Intro and Multibitrate Encoding (my general overview of Smooth Streaming)
• Encoding Big Buck Bunny for SmoothHD.com (highy nerdy hands-on example… with tables and charts!)

Alex Zambelli

Alex has been doing a great series on multibitrate streaming, adaptive streaming, and Smooth Streaming architecture from a content authoring perspective. They’re great to go through in order

1. A Brief History of Multi-Bitrate Streaming
2. The Birth of Smooth Streaming
3. Smooth Streaming Architecture

John Bocharov

John is an IIS Program Manager who has been intimately involved with Smooth Streaming since its inception.

• Beta Release of Smooth Streaming Now Available
• Smooth Streaming Questions? We’ve Got Answers!
• I’ve seen the future and the future is… Smooth!

• A new Silverlight 2 base player using .NET. Among other things, this will enable players that display the video at 100% scale by default, improving quality and performance.
• New A/B compare modes. Awesome stuff for high-touch encoding and codec tweaking
• Some even more VC-1 advanced options for High Codec Nerditry.
• The first public release of Microsoft H.264 compression technology.

Anyway, a lot of good stuff for a SP1. I'm looking forward to it.

The big news is that, yes, we're going to add support for MPEG-4 to Silverlight, in the version coming after the fast-approaching fall release of Silverlight 2. Specifically, this will be H.264 for video and AAC for audio.

Why?

So, why MPEG-4 support in Silverlight? It's pretty straightforward, really. We have customers with libraries of H.264 content they wanted to publish to Silverlight, but didn't want to reencode to VC-1. Silverlight's strengths go far beyond media playback, and customers wanted the choice to deploy a wide variety of existing content within Silverlight. Silverlight aspires to provide as much choice as feasible as to how Silverlight can be authored and delivered. H.264 support is something we'd considered for past versions, but there were higher priority features we needed to deliver first. Silverlight 2 provides us a very rich base for delivering web apps, so we can start spreading our wings a bit.

What?

We've got more technical details we'll be sharing at IBC and later, but today, I'll just quote the details from Scott Guthrie's interview:

PressPass: Will you be showing or announcing anything new at the IBC conference this week?

Guthrie: Yes. At IBC 2008 we will be demonstrating a technology preview of H.264 video and Advanced Audio Coding (AAC) audio playback support in Silverlight, and H.264 authoring using Microsoft Expression Encoder and Windows Server 2008 for delivery. Until now, Silverlight has supported the SMPTE VC-1 and Windows Media formats, as well as MP3 for audio, enabling customers to take advantage of broad support across the Windows Media ecosystem, including third-party tools, service providers and content delivery networks.

We’ve always wanted Silverlight to support a variety of formats, so today we’re announcing that H.264 and AAC support will be available in a future version of Silverlight, which will offer content owners greater flexibility and choice to deliver video and audio.

PressPass: Historically, people have associated Microsoft with VC-1. Does this signal a change in direction?

Guthrie: No. Although we have been working with VC-1 for some time, it’s not widely recognized that Microsoft has also been an active participant in the standardization of H.264/MPEG AVC for many years, and we’ve included H.264 support in several Microsoft products. Microsoft’s Gary Sullivan was the chairman of the Joint Video Team (JVT), which developed the H.264 standard, and he recently accepted an Emmy Award on behalf of the JVT.

PressPass: Does this mean that Silverlight is moving away from Windows Media?

Guthrie: Not at all. This is about offering our customers more choice. Media producers and distributors around the world have enjoyed the high quality, flexibility and affordability of Windows Media formats for over a decade. As a testament to its pervasiveness, Windows Media can be found in almost every conceivable media scenario from desktop home video to feature films and TV broadcasts.

Again, don't read this as as a big change around our strategy for media formats. We've long-supported WMV and MPEG-4 side-by-side in products like Xbox and Zune. As I posted last week, Microsoft has been contributing to H.264 since its inception.

This doesn't represent any change in our support for Windows Media. Windows Media continues to work well for today's Silverlight customers. I expect (not a goal, just a prediction) that the majority of Silverlight content will remain in WMV well after we release MPEG-4 support.

In particular, VC-1 will likely remain the codec of choice for HD for some time. Comparing VC-1 Advanced Profile to H.264 High Profile with all the bells and whistles turned on, VC-1 only needs about half as many MIPS per pixel for playback. This won't matter as much for lower resolution content, or podcasting stuff that's in the simpler Baseline profile, but makes for a big reduction in system requirements for 720p and higher.

Where/When can I learn more?

If you're at IBC, swing by! If you want a head start on using MPEG-4 in Silverlight, feel free contact me directly. And we'll have plenty of more technical info to share down the road a bit.

So, I was really excited that our own Dr. Gary Sullivan, chairman of the Joint Video Team, was on hand last week to receive a 2008 Primetime Emmy^® Engineering Award for developing H.264/MPEG-4 AVC High Profile. In the words of the Academy:

Joint Video Team Standards Committee (JVT) for the development of the High Profile for H.264 / MPEG-4 AVC. The High Profile enables high definition images in the H.264 video coding system used today to deliver HD video over satellite and cable TV as well as Blu-ray Disc. The JVT is a standardization team comprised of members from the International Standardization Organization (ISO), the International Electrotechnical Commission (IEC), and the International Telecommunication Union (ITU).

The award recognized Broadcom, NTT DoCoMo, Dolby Laboratories, Fraunhofer Heinrich Hertz Institute, Microsoft, Motorola, Panasonic, Sony, and Thomson as contributing companies, as well as standards organizations ISO, IEC, and ITU.

Gary has long represented Microsoft as as chair and co-chair of the Joint Video Team that coordinated the H.264/MPEG-4 AVC effort between ITU-T VCEG and ISO/IEC MPEG, amongst his many other efforts like DXVA; his page on Wikipedia has more details.

I suppose some people might be surprised at Microsoft's inclusion here, but they shouldn't be. While Microsoft has a long heritage of making our own ground-up codecs like VC-1, we've also long been involved in standards-based codecs, including the original MPEG-4 Part 2 as well as MPEG-4 Part 10/H.264. And we've got a number of products that incorporate H.264 today, including Mediaroom, the Zune 4/8 and 80, and Xbox 360. H.264 are and VC-1 are both great codecs, with somewhat different sweet spots, and we use either or both as appropriate in our products, platforms, and services.

The picture above has, left to right: Malcolm Johnson (director of the ITU standardization bureau), Ajay Luthra (JVT vice-chair from Motorola), Gary Sullivan (JVT chair from Microsoft), Thomas Wiegand (JVT vice-chair from Fraunhofer HHI), and Scott Jameson (chair of ISO/IEC JTC 1)

And a few other articles/posts about the award:

ANSI

EE Times

Dolby

Minoru "Mick" Etoh's blog (who represented DoCoMo at the ceremony)

Compression, although an obsession with me since I was 19, didn't appear to be a career option until many years after that. My years at Hampshire College were spent essentially majoring in neuropsychology, minoring in computer science, and spending my evening and weekends helping out my film student buddies. It all seemed hopelessly random to my parents and advisors, but turned out to be the perfect background for what I do now (after all, what's compression but extremely applied neuropsychology?).

After college and a couple of science internships under my belt I decided I didn't want to spend my life writing grant proposals or doing lab work so I started a video production company with my friends, including my recent interviewer Halstead York. The plan was to use emerging technology to be able to produce and post independent films from our own scripts. We thought we had a financing deal lined up back in 1994, and purchase a NLE: (a PowerMac 8100/80 with a Radius VideoVision card, and 4GB SledgeHammer RAID) was purchased for doing video editing. The idea was we could rent it out before and after post in order to cover some of the costs. Then there were two big problems:

1. The infamous defective BART chip in those early PowerMacs meant it couldn't keep sync for more than a few minutes.
2. Our financing fell through.

So, there we were, with a script, no money, a bunch of debt, and a NLE that couldn't edit video. However, we found a nice market using shorter clips with looser sync requirements: CD-ROM video! And so we were launched in the heady early days of multimedia. Journeyman Digital was a full service production company for digital media, and we did all the screenwriting, production, and post that we dreamed of, but not for our own projects. But we kept writing screenplays on the side. We got as far as a few meetings with Sony Pictures on one, but like nearly all screenplays, nothing really happened in the end. And while I liked doing the work, when it came down the the fundamental gut check of moving to LA and rolling the dice, I didn't NEED to do it. Instead I got married and soon enough had three little kids, and rather ran out of time for side projects.

Halstead is only recently married and currently kidless, and had time. So he and many members of the old gang dusted off one of our old screenplays, Temporary Insanity and darn if it they didn't actually shoot the whole thing in HD! Halstead just finished up the trailer. Quite an experience seeing jokes I wrote a decade ago there on the screen. And it's amazing to see how it's finally possible to make movies on a hobbyists budget, even with high-end techniques. Check out this post on color correction in the home office.

I didn't have time to work on the production itself (I was busy having that third child get born and joining Microsoft), but I certainly wasn't going to let anyone else compress the trailers (now available for download)!

The project

And so, after all that ramble, we're back to talking about hands-on compression.

Halstead had a pretty typical 2x2 matrix for encoding: two formats at two data rates each:

Formats

• MPEG-4 compatible with QuickTime/AppleTV/iPod
• Windows Media compatible with Windows Media Player/Flip4Mac/Xbox/Zune/Silverlight

Data rates

• 3 Mbps for a 720p30 HD version compatible with Xbox360/AppleTV
• 300 Kbps for a low data rate download, which would also be portable media player compatible (iPod for .mp4, Zune for .wmv)

Workflow

The source was provided as a 730p30 .AVI file using the CineForm Aspect HD codec. It was video-only - audio was provided in a separate .wav file.

HD WMV encoding was easy - I was able to use the source as is. And the current WMCmd.vbs supports specifying a separate .wav file as source for the audio track.

HD .MOV was harder. I wanted to use QuickTime's H.264 encoder to output, since it uses a complexity-constrained mode that is well tuned for computer playback via QuickTime, on both Intel and PPC (and there's a lot of G4 PowerBooks out there among Indie film fans). While it won't offer the same compression efficiency as a highly-tuned H.264 encoder from another encoder, it'll also playback well on more machines.

However, QuickTime, even QuickTime for Windows, can't read AVI files using the standard DirectShow API! Now that we've added support for the QuickTime API in Expression Media Encoder, it's only fair for Apple to support DirectShow now . So, I used Rhozet Carbon to encode my .avi and .wav source files into a single Photo-JPEG compressed .MOV file that QuickTime could then read (believe it or not, there's no lossless Y'CbCr 4:2:0 encoder in QuickTime for Windows). I wound up doing that compression on my G5, so I could do it in parallel with the WMV encoding on my Windows box.

For the mobile versions, I used VirtualDub to make me a nice 320x180 version of the .AVI and Carbon again to make a 320x180 JPEG .mov.

As an alternative (and what I would have done if this was going to be a high-volume process and not just a one-off) would be to using Carbon to encode all four outputs from the single source. Also, using the "multipass" mode with Carbon and other tools other than QuickTime Player Pro itself results in very, very slow rendering time, since it reruns preprocessing for the entire clip for each pass, although only a small part of the file might be adjusted per pass. So in a high-volume workflow, probably only the 1-pass mode would have been used.

Windows Media Settings

WMV HD @ 3 Mbps:

cscript "C:\Program Files\Windows Media Components\Encoder\WMCmd.vbs" -input "G:\Temp Insanity\Trailer 1 timed v5 720.avi" -output "Trailer 1 720p 3M 192.wmv" -a_input "G:\Temp Insanity\Trailer 1.wav" -a_codec WMASTD -a_mode 4 -a_setting 128_48_2 -v_codec WVC1 -v_mode 4 -v_keydist 5 -v_bitrate 2870000 -v_peakbitrate 6000000 -v_peakbuffer 4000 -v_performance 80 -v_bframedist 1 -v_dquantoption 2 -v_loopfilter 1 -v_mmatch 0 -v_mslevel 4 -v_msrange 0 -v_percopt 2

Pretty standard stuff, with the same basic settings as my previous encodes. A few items of note:

1. Not excessive vertical motion and HD, so I didn't bother constraining the number of threads.
2. Since the source was just stereo, I used WMA instead of WMA Pro, in order to preserve Silverlight 1.0 compatibility.
3. Note the use of the -a_input flag to specify a different audio source.

WMV mobile @ 300 Kbps:

cscript "C:\Program Files\Windows Media Components\Encoder\WMCmd.vbs" -input "Trailer 1 timed v5 320x180.avi" -output "Trailer 1 280 Zune.wmv" -v_codec WMV9 -v_mode 4 -v_keydist 10 -v_bitrate 235000 -v_peakbitrate 600000 -v_peakbuffer 4000 -v_performance 80 -v_bframedist 1 -v_loopfilter 1 -v_overlap 1 -v_mmatch 0 -v_mslevel 2 -v_msrange 0 -v_percopt 2 -v_numthreads 1 -a_codec WMASTD -a_mode 4 -a_setting 48_44_2 -a_peakbitrate 160000

Pretty much identical to the Zune encoding settings I posted last week, except with lower data rates to hit the 300 Kbps total.

1. The audio was pretty simple, so 48 Kbps was enough when using VBR mode (again VBR audio is a very underused and very useful feature for downloadable files).
2. the data rate was so low, I went to the max and used -mslevel 2 (full floating point chroma search) and -v_numthreads 1 (single-thread encode). Even with those, this encoded much quicker than the HD version, since the frame size was so much smaller.
3. Main Profile is required by Zune, and thus I can't use DQuant.

QuickTime Settings

QuickTime's advanced settings aren't available via command-line, so I'll include screen shots of my MPEG-4 settings.

I matched the WMV settings as closely as appropriate.

MPEG-4 Main Profile @ 3 Mbps

1. The "Current" mode passes through the source frame size and frame rate (Note it would have said 1280x720 (Current) above - I had a different source loaded when I took the screen shot).
2. "Optimize for Download" is the equivalent of our 2-pass VBR modes. However it lacks the ability to specify a peak buffer rate or duration.
3. QuickTime specifies keyframe rate in terms of total frames between keyframes, not total seconds.
4. The "Better" mode for audio encoding quality is optimal for 16-bit sources. The "Best" mode only improves >16-bit sources
5. The Multi-pass mode improves quality, but can make encoding time very unpredictable. The WMV versions encoded quite a bit faster on a similar era machine (Dual 3.4 GHz "NetBurst" Xeon versus dual 2.0 GHz G5). My main compression box, a quad AMD, was busy doing some other work.
6. QuickTime lacks a true 2-pass VBR audio mode. For MPEG-4 exports, I only get 1-pass CBR. With a QuickTime export, I could have gotten a 1-pass VBR encode, but only in a MP3 style "range" encode, where the final file size could vary substantially. For soundtracks in downloadable files, this makes WMA a more efficient codec.
7. Main Profile is compatible with AppleTV, and uses B-frames. The "Extended" profile is theoretically for streaming, but it's been grayed out in QuickTime since H.264 support launched in QuickTime 7.0, and I've never seen a H.264 Extended Profile stream in the wild.

The mobile encode was the same, except with the lower video and audio data rate, and its use of the Baseline profie, required for iPod compatibility.

Differences

So, how did the two encodes come out?

For the most part, they both looked and sounded good (or at least accurate - the audio mix will be improved in a later version). The biggest difference was in flatter areas, especially with shadows. That's where the VC-1 Differential Quantization and Perceptual Optimization come in, plus the ability to use different block sizes(4x4, 4x8, 8x4, and 8x8), to better compress the edges and interiors of flat areas. The Baseline and Main Profiles of H.264 are limited to 4x4 blocks only, and H.264 doesn't have an equivalent mechanism to DQuant to compress flat areas of the image less.

Again, another H.264 encoder could have done a better job here, although at the cost of higher decode requirements, by using features like CABAC and multiple reference frames. High Profile, and hence 8x8 blocks, are not compatible with QuickTime's H.264 decoder, nor those in the AppleTV or iPod. The iPod-required Simple Profile doesn't support B-frames or CABAC.

Here's some samples from the available clips that show different levels of banding. Sorry the luma levels don't quite match - it's surprisingly difficult to get exact level screen grabs out of the QuickTime and DirectShow pipelines. If anything, these minimize the banding seeing in the clips when looking at them in QuickTime on a Mac (2.2 to 1.8 gamma correction issue?).

H.264:

VC-1:

H.264:

VC-1: