Japanese version of i-motion technical specification has more information. Describes different versions of Mobile MP4. See also i-motion handset support
- Vast majority support Mobile MP4 (3gp)
- N2102V/F2102V and later models include AAC audio codec
- There are 2 types of video distribution methods for i-motion
- Download all at once and playback
- Size limit: from 300 KB on older to 10MB on recent handsets
- Progressive download (start download, cache chunk and play)
- uses range-request
- Download all at once and playback
Vlive is a streaming service
- to be discontinued in 2010
- Called "EZ ムービー" au supports two container types, AMC (mp4, mp3/qcelp) and 3gpp2 (mp4, AAC/AMR).
- distribution is by download or progressive download
- Size limit for progressive download is 140KB (per chunk?)
- Size limit for download is 512KB (AMC) and 1.5MB (3gpp2) for newer W-series handsets
supported video / sound formats: http://www.au.kddi.com/ezfactory/tec/spec/4_5.html
Video Sharing Services
YouTube provides users with a download link a file. The format of the file depends on the user agent. In the case of Japanese phones, it it appears to always be transcoded to 3gp. It doesn't appear to take in to account handset limitations, as the resulting file will not necessarily play on all phones. For example, a file over 2mb do not play properly on our au phone.
YouTube allows users to upload videos via mobile. To do this, send an email to address in your profile under "Mobile Setup" with the video as an attachment.
The initial email address given to me when I first visited the Mobile Setup page under location "Worldwide" and language "English" did not work when I sent a video to it as an email attachment. When I change the location to Japan and language to Japanese, I was given another email address, which did allow me to upload successfully. After I had pressed the save changes button in Japanese and returned to English, the new address remained.
Nico Nico Douga
A popular Japanese video sharing site. Users are required to login to view videos. Key feature is the ability to write comments over videos. Videos are played through an i-Appli for docomo and flash lite 2 for au.
MyTube allows users to view videos from other sites, such as YouTube, on the mobile. When a user finds a video he wants to watch, he clicks a link on the video which starts the transcoding process for that user. When the video is finished being transcoded, it is added to his list of videos. The video will be broken into several chunks to avoid the size limits of mobile phones.
mixi allows users to upload videos via email attachments. To do this, a user first has to enter his mobile email address in the PC website. Doing this will send an email to his mobile, and any mails sent to the sender's mail address will be uploaded as video to his account. A user can play videos either by streaming or downloading them.
Commercial transcoding services
On the fly Appliance/ASP services
When you want to host content yourself but would like to distribute to keitai, you might be interested in looking at existing transcoding services.
Japanese handset support
snapVu is an appliance type solution.
motion fitter seems to be an ASP service, with a free trial.
ストレンモビ seems to be another ASP type service.
optmovie is yet another ASP type service.
keitai-video by fujifilm has complete solutions for image and video
Japanese handset support unknown
If you want to build your service yourself, you can either opt to use Open Source components that are built around ffmpeg or use commercial packages like Episode Engine. Be aware that there are patent issues involved with some codecs so do your research beforehand.