The thing that annoys me about both this and Zencoder is that for people who are actually experienced with video encoding, there is absolutely no way to tweak eg. the underlying x264 settings. There's quite a few settings that have no effect on decoding in any way but are pretty important in getting the most out of the video at a given bitrate (most notably the strength/mode of AQ and psychovisual optimizations). In case of AWS, there doesn't even seem to be any kind of "general" tuning (like whether the content is film, animation, extremely grainy or so - x264 has --tune settings for these among others - Zencoder at least allows you to access this option) options available, making it pretty much "one size fits all". I could always rent a generic server and use that for my encoding needs, but it'd be much more convenient if these cloud transcoding services simply offered advanced configuration for people who know what they are doing.
Also, even for a "simple" cloud transcoding service, Amazon's offering is pretty limited in what it can do right now - you can basically only encode H.264 & AAC in MP4, define the profile, level and bitrate, and that's about it. Zencoder has much more options in comparison and has generally more transparency in regards to what their encoding software actually does (sadly when I asked them about getting access to x264 settings directly, they replied along the lines of "they could change and things might break for users!" - which I don't think would be an actual issue since the direct settings ought to be for advanced users only, and they should be aware of things changing - plus Zencoder could just notify users of direct settings before they upgrade so they have time to adjust their settings if necessary).
As is the case with every part of AWS, we add additional features and options over time based on customer feedback and requests. Please feel free to let us (or me -- email@example.com) know what you need and I'll bring it to the team's attention within 30 minutes.
A really simple way to obtain very high quality per bit per second, given prior knowledge of the nature of the material (film or not, grainy or not, cartoon or not, etc) and the type of output desired (AVCHD, Blu-Ray, etc) is to install MeGUI, then pick one of the community-built encoding profiles for x264.
Choosing the right profile for the job is absolutely crucial. The combinations of x264 parameters can be pretty arcane, and they sometimes change from one x264 version to another. There's a pretty active community on forum.doom9.org maintaining collections of profiles for MeGUI, some of those are excellent.
E.g., it is totally within the realm of possibility to put two hours of 1080p content on a single-layer DVD (4.4GB), in a format compatible with any Blu-Ray player out there (AVCHD, a subset of the Blu-Ray standard that accepts DVD as the storage layer), while keeping video quality at a very high level - basically indistinguishable from commercial Blu-Ray discs. But using a good encoding profile, feeding the appropriate parameters to x264, is the single most important factor in achieving that goal.
MeGUI is hardly necessary - x264 has a good set of presets and tunes built in to begin with. --preset veryslow --tune film/animation/grain will already get you very far, beyond that pretty much the two most important things to possibly tweak are the strengths of AQ and psychovisual optimizations (--aq-strength and --psy-rd).
>it is totally within the realm of possibility to put two hours of 1080p content on a single-layer DVD (4.4GB), in a format compatible with any Blu-Ray player out there (AVCHD, a subset of the Blu-Ray standard that accepts DVD as the storage layer), while keeping video quality at a very high level - basically indistinguishable from commercial Blu-Ray discs.
You might get away with an hour of almost-transparent content if it's not particularly bitrate-demanding, but two hours of live action will not look "indistinguishable from commercial Blu-ray discs". 5 Mbps High Profile L4.0 H.264 just won't look as good as ~30-40 Mbps H.264 High Profile L4.1 H.264 commonly found on BDs (unless the BD is really screwed up). At 720p you'd get pretty good results, though.
There has to be webm output support, firefox and chrome don't support mp4. And as always, it would really be helpful if s3 supported notifications, so you could automatically put a message into SQS or add a job to this new transcoding service when a file is uploaded to a bucket.
Chrome still supports MP4 as far as I know. They mentioned dropping support a couple of years ago but didn't.
Firefox is getting MP4 support. Firefox OS and Firefox for Android on some devices has it already. Support on some versions of Windows is in nightly builds hidden behind a preference setting. Linux support is hidden behind a build switch. At some point when these backends are stable they'll be in normal builds.
I thought chrome did drop it and microsoft released a plugin?
Firefox getting mp4 support doesn't change anything, people are already using firefox right now, and it doesn't support mp4 right now. The fact that the marketshare of non-mp4 firefox will eventually end up small enough that most people ignore it doesn't mean mp4 is all people need right now.