My “secret recipe” for amazing image quality with video downloads via the web is not so secret, I’ve been using the H.264 (a.k.a. MPEG-4 Part 10) codec along with AAC for the audio. H.264 is much more efficient than previous MPEG codecs (compared to MPEG-2, H.263, or MPEG-4 Part 2) and thus requires half of the bandwidth for the same image quality as the previous codecs. By the way, H.264 is the codec used in the HD-DVD standard, as well as Blu-ray Disc, and many broadcast applications, it’s the wave of the future and it’s here today.
In terms of compression tools, I suggest using QuickTime Pro to convert your HD or DV video masters to compressed form. Sorenson also offers an implementation of H.264, the Sorenson AVC Pro codec is now available in Sorenson Squeeze and I would imagine Media Cleaner now offers it too, but I’ve not used cleaner in a long time, as QuickTime export has been working out well for me. If your using Avid and not Final Cut, I imagine you can export from Avid using “QuickTime conversion” just like you can from Final Cut, but I don’t have a Avid handy to check this out as I write this.
The video I’ve been working with recently is compressed from Final Cut Pro using the “Export => QuickTime Conversion” menu and then selecting the desired options (described below).
The only downside is that older systems can’t play the movies, they require QuickTime 7 for Windows (running 2000 or XP) or Macintosh (running Panther or Tiger), there are other options for playing back H.264, however, QuickTime 7 is by far the easiest in install and use, and it’s a free download from Apple. QuickTime 7 Pro offers additional features for $29.95. This will be required for it’s authoring features that include creating video for iPod, simple cuts-only editing with cut, copy and paste simplicity, and convert (or export) media formats as described in this post.
From Final Cut Pro I’ve been making movies for download (and playback using QuickTime 7 player or Browser Plug-In with QuickTime’s wonderful “Fast Start” capability that offers download quality and streaming performance (with a fast Internet connection) that beats hands down other download or streaming video options in terms of overall quality and experience.
Export Option: Movie to QuickTime Movie
Compression Tool: Export using QuickTime 7 Conversion via Final Cut Pro
- Size: Use Custom Size: Width: 320, Height: 240
- Movie Settings: Compression Type: H.264
- Movie Settings: Frame Rate: 15fps
- Movie Settings: Motion: Key Frames: Automatic
- Movie Settings: Motion: Frame Reordering is checked
- Movie Settings: Conpressor: Quality: Best
- Movie Settings: Compressor: Encoding: Best Quality (Multi-Pass)
- Movie Settings: Data Rate: Data Rate: Restrict to 300 kbit/sec
- Movie Settings: Baseline Low-Complexity Profile
- Movie Settings: Prepare for Internet Streaming (checked on): Fast Start (select this option from the pop-up)
- Sound Settings: Format: AAC
- Sound Settings: Channels: Stereo (L R) (and you can
save a little bit rate if you go for Mono).
- Sound Settings: Sampling Rate: 41KHz
- Sound Settings: Sample Rate Converter Settings: Quality: Best
- Sound Settings: AAC Encoder Settings: Target Bit Rate: 64 kbps (or 96 kbs for better stereo audio, do some tests and find what’s acceptable to you)
For viewing on computer screens when there’s not a lot of motion, you save big time bringing the data rate down to 15fps.
QuickTime’s Fast Start feature allows the QuickTime player (or Browser Plug-In) to start playing the movie before the download completes. If movies stutter or stop on playback via the web, see the support page “ Getting the best playback with Internet movies” on the Apple web site.
This combination of video and audio settings will end up limiting the the total data rate to 364 to 396 kbit/sec which yields acceptable 1/4 screen playback (320 x 240) and reasonable download times with home DSL and Cable Model connections. If you have a lot of complex music and your audio track is stereo, you might want to bump the AAC Encoder Target Bit Rate up to 128 kbps.
One price you pay for the the improved image quality of this recipe is that given the H.264 codec and choosing the best quality multi-pass compression, it will take a long time for your movies to compress, but the wait is worth it, like a fine Cabernet.
One issue is that this movie will be small and download quickly, however, for use with an iPod via iTunes there is one small problem, the movie will require conversion in iTunes before it can be dragged directly to a video iPod.
You can create movies that can be dragged directly to a video iPod without conversion if you choose the Export: “Movie to iPod (320 x 240)” setting instead of the Export: “Movie to QuickTime Movie” setting, however, it creates movies that are about 30% to 50% larger than the settings I prefer to use. Maybe this will work itself out over time…
For a SEAMLESS direct download and iTunes/iPod experience, you might consider offering two options, but then it starts to get messy. I’ve not found a set of settings yet that yield the BEST OF BOTH worlds, drag to iPod without conversion and smaller file size for better playback via download. This is an ongoing investigation.