The presentation illustrates how a Japanese streaming service handles chaotically supplied contents for 24/7 linear streaming. It also describes the background behind the fact that unique circumstances between the video streaming industry and broadcasting industry in Japan create the chaos.
A Japanese Way to Maintain Constant Quality on Streaming Chaotically Supplied Contents
1. A Japanese Way to Maintain Constant Quality
on Streaming Chaotically Supplied Contents
Yusuke Goto, AbemaTV, Inc.
- 2019.11.10 Video Dev Days 2019 -
2. Yusuke Goto
五藤 佑典
https://ygoto3.com/
@ygoto3_
● Majored in Graphic Design at California State University, San Bernardino
● Software engineer @ CyberAgent, Inc. and AbemaTV, Inc.
● AbemaTV Development Division
○ Lead New Device team
○ Lead Streaming Client team
○ A Developer Expert in video technology and product design
3. Everything about video tech in Japan is unique.
Unique practices, original specifications ...
6. We do
● Studio work
○ Shooting
○ Editing
● Production
○ Pre-production
○ Post-production
● Mastering
● Development
○ The streaming system
○ The applications
○ The ad system
● Ad production
12. -24.0
LUFS
Linear Streaming and Server-Side Ad Insertion
CFR
Progressive
Interlaced
-18.0
LUFS
VFR
16:00 - 17:00
Slot A - Purchased
17:00 - 18:00
Slot B - Recorded
18:00 - 20:00
Slot C - Live
20:00 - 21:00
Slot D - Recorded
13. Example : AbemaTV’s Ad Regulation for Submission
Duration 15s/30s/60s/90s/120s/150s/180s/300s
Container Format MP4
Frame Size Full HD (1920 x 1080)
DAR 16:9
Video Bitrate (avg.) 20 Mbps
Video Encoding Mode 2-pass encoding
Scan Type Progressive scan
Video Codec H.264
Frame Rate 29.97 fps
Profile High Profile / Main Profile
Audio Channels Stereo 2ch
Audio Codec AAC-LC
Audio Bitrate 320 Kbps
Audio Bit depth 16 bits
Audio Sampling Freq 48 kHz
Audio Peak Level >= -3 dDBFS
Loudness (avg.) -18.0 LUFS ± 1LU
15. Sources Come from Everywhere
● Broadcasters
○ Their workflow is much simpler and
fixed
● Masters for BD/DVD
○ Too much info
● Old contents
○ Legacy codec
■ Can’t handle
w/ the latest software
● Sources originally for another purpose
○ Digital signage
○ Web video
■ Fewer framerate
■ VFR
○ Archives of game streaming video
○ Hardware-dependent codec
■ Via hardware-recording
● Multi-language sources
○ Multi-track
■ Primary tracks platform-dependent
● etc.
○ All the video sources that
are not optimized for streaming
20. Why MP4 ?
● Good for our needs
○ Small file size
○ Good compression for 4:2:0 chroma subsampling
■ Good enough as a de facto media format
○ Decodable everywhere
■ Playable everywhere
○ Fast transcoding
○ Simple structure
■ Easy to handle GOP
■ Easy to convert sources to I-frame-only data
21. Why MP4 ?
● MP4 already seems to be the standard for delivery
○ Major media solution providers primarily support MP4
■ AWS Elemental MediaLive
● mp4 only
■ Harmonic
● mov/mxf/mp4 - (mp4 is the stablest)
■ We do not use these solutions, but good to have other options
23. MP4 is hard to handle
● MP4 is an effectively compressed format
○ Easily succeeds negative factors from the original sources
■ Broken decode order
■ Wrong header info
Not all the content operators are video experts
27. A MAM solution is good, but ...
● Does not support all the media formats we receive
● MAM companies are usually not familiar with the Japanese manner
○ e.g., DALET is a French company
○ 30 fps / NTSC ? No, PAL does not use it
35. Loudness
-18.0 LUFS
● AbemaTV’s original specification
○ ARIB T032 specifies -24.0 LUFS
■ Not enough for mobile devices
○ Optimized for playback on mobile devices
○ Follows AES’ Recommendation for Loudness of Audio Streaming &
Network File Playback
■ -16.0 to -20.0 LUFS
37. Various Kinds of Platforms to Support
● iPhone
● iPad
● Apple TV
● Android Smartphone
● Android Tablet
● Android TV
● Fire Tablet
● Amazon Fire TV
● Google Chrome
● Mozilla Firefox
● Internet Explorer
● Microsoft Edge
● Apple Safari
● Google Chromecast
● Google Daydream View
● Amazon Echo
● LINE Clova Desk
● SONY BRAVIA
● Panasonic VIERA
● TOSHIBA REGZA
● Sharp AQUOS
● FUNAI
● LEOPALACE21
Life Stick
● CCCAIR Air Stick
● ...
50. Conclusion
● To keep constant quality on streaming chaotically supplied contents
○ Developed a unique and original specifications
○ Partly adopt parts of various standardized specifications
○ Developed tools and workflow to patch gaps