Improving Video Quality for Crunchyroll and VRV

Michael Dale
Mar 16, 2017 · 4 min read

At Ellation we have been hard at work rolling out updated encoding settings to drive increased video quality for Crunchyroll. This work includes improvements to quality for both our HD viewers and those on limited bandwidth, to get the best quality possible for the device.

Traditionally, Crunchyroll video has been served out of datacenter infrastructure. However, to scale with the launch of VRV and the growing Crunchyroll audience we decided to transition to cloud encode and delivery. This transition to the new cloud delivery infrastructure is starting to drive greater stability in video serving and involved using an alternate set of encodes. These encodes were affected by a mistake in our encoding settings discovered after the catalog had been encoded. We have been using these problematic encodes for distribution a day or more after publishing the simulcasts and were progressively reducing this delay. The Crunchyroll community rightfully raised concerns that these transitional encodes are not up to the quality we intended. We apologize for not hitting the high quality bar that we are committed to delivering throughout the entirety of this transition as well as for any confusion this may have caused.

Today we are rolling out some of the encode profiles we are transitioning to as part of the new cloud video encoding infrastructure. We see these new encodes as the upper end of online streams for anime available anywhere. You will see these updated encodes immediately for all simulcasts going forward. The entire back-catalog will also be refreshed with updated settings as we complete our transition to the new cloud platform as originally intended.

Whats changing?

Crunchyroll old video infrastructure encoder quality used a flat bitrate (ABR) across all episodes and series. This resulted in a one size fits all for every show where episodes used a fixed bitrate to meet quality expectations. Similar to Netflix’s transition to per content encoding, Ellation has started moving to more variable bitrates and per content constant quality (CRF) settings. This transition enables bandwidth constrained consumers on mobile devices to experience much higher video quality since video bitrate is not artificially constrained to high value as with the old video encoding infrastructure. As outlined in the samples below, some complex scenes could use more bitrate than Crunchyroll old video encoding infrastructure had allocated them. With this new encoding scheme we will continue to refine and ensure a high level quality in a much broader set of content scenarios.

Spoilers Alert

For example “My Love Story, episode 14” at 19:38, when Takeo and Rinko go to an amusement park with a girl who’s trying to split them up; she ultimately decides not to and Rinko and Takeo get to enjoy the parade together there is a scene of flashing lights that is traditionally challenging for encoders.

Screenshot Disclaimer: We are sharing some quick samples here, please watch this space more formal analysis.

The original scene from the source mezzanine

For this scene we can look at the 3 encode settings we now have active on crunchyroll.

Our misconfigured encoder settings
You can see a degradation of the arm gradient.

With our historic Crunchyroll encodes we do a lot better with a very high constant bitrate but still see some minor degradation.

Old Crunchyroll encodes
The old Crunchyroll encodes.

Finally our newest encodes allow for more bitrate for complex scenes to slightly better capture details as available from the original mezzanine.

New encodes of the same scene.
New encode detail zoom

You can take a look at these new encodes in the My Love Story series and all simulcasts going forward.

Please watch this space for additional technical details regarding the encoding techniques being employed as we plan to share many more about our encoding and technology platform going forward.

Throughout 2017 we have big plans to test newer codecs such as VP9 and work with upstream content partners to drive quality and resolution upward. If you’re interested in joining the efforts and many other exciting projects for Crunchyroll and VRV please get in touch.

The Ellation Video Team

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