Crunchyroll and 1080p streaming
So, Crunchyroll (shortened to CR from now on) announced that they are starting to stream series in 1080p (1920x1080 video at 23.976 progressive frames per second). Seeing their proud claims about ”Things never looking so clear!” and a couple screenshot comparisons, I decided to investigate the subject myself and see how CR's 1080p encodes fare in reality when compared to TV broadcasts.
First, let's take a look at CR's marketing claims, namely this post. They claim to have ”two times [the bitrate] of 720p & only offer 1080p if we truly have the appropriate source. No upscaling!” First, let's look at the bitrate. Their 1080p streams have a bitrate of 3072 kbps. This would indeed be twice the bitrate of their 720p streams... if it wasn't for the fact that some time ago, CR upgraded their 720p streams from 1500 kbps to 1776 kbps. So in reality it's only 1.75 times the bitrate of the 720p for 2.25 times the pixels. Bitrate requirement doesn't really scale in a linear fashion with the pixel count, though, especially when you're dealing with upscaled material, which leads me to their second marketing point...
But before we get to that, we need a bit of background. What CR gets as masters is very often the same thing that TV channels in Japan get: HDCAM tapes. The resolution on these tapes is anamorphic 1440x1080, the same that basically all TV channels in Japan broadcast. The video is also hard telecined from 23.976 to 29.970 FPS, so an inverse telecine (shortened to IVTC from now on) is required to get the material back to the original progressive 23.976 FPS framerate. When CR says that they ”have the appropriate source” for 1080p streams, they mean these HDCAM tapes.
However, and this is important, just because they get a HDCAM tape at 1440x1080 does not mean that a show would have actually been produced or mastered anywhere near that resolution. This becomes painfully evident when looking at their 1080p streams for shows like Naruto, Fairy Tail and Bleach. Or does any of these shots look like ”genuine HD material” to you? The only thing even remotely HD there is the overlaid lyrics and credits on Naruto, and that's it. So while CR technically isn't lying when they claim to have ”HD sources” (since the HDCAM tapes have a high-definition resolution), that still doesn't make the shows itself mastered or produced in 1080p or anywhere near it. (Update: CR & co. generally do not get physical HDCAM tapes in the mail, but the sources they do get have been made from such HDCAM tapes, so it's basically the same thing either way.)
Anyway, moving on to the actual quality of their 1080p streams. I'll start by saying that I was notably disappointed after seeing some user-made comparisons of Nisemonogatari, since it turned out that it was one of their few actually pretty nice 1080p streams. However, for the most part, they only fare questionably better than the TV broadcasts or even worse in some cases.
For this comparison, I have looked at the 1080p CR encodes for the following shows along with their respective TV broadcasts (listed in Show Name [TV channel] format):
- Another [Tokyo MX]
- Nisemonogatari [Tokyo MX]
- New Prince of Tennis [TV Tokyo]
- Natsume Yuujinchou Shi [TV Tokyo]
- Fate/Zero [Tokyo MX]
- Mouretsu Pirates [MBS]
- Inu x Boku SS [MBS]
- Brave10 [Tokyo MX]
- Ano Natsu de Matteru [TV Aichi]
You can find various amounts of screenshots for all of these here.
Ranking has been divided into four different parts: Overall quality, Sharper picture, Color difference and Need for filtering.
- Overall quality: A rating of the overall picture quality, ranked from zero to ten.
Note that this scale is for ”TV quality” - Blu-rays would rank somewhere around 15-18 on this scale.
- Sharper picture: A simple one – which one offers sharper details.
- Color difference: All the CR encodes seem to have some kind of difference in color contrast/brightness compared to the TV broadcasts. This is likely to be an error on CR's part, since TV broadcasts generally have basically identical colors to Blu-rays. Rated with stars from 1 to 3 depending on the severity. It's not that bad even at worst, but still notable when compared to TV broadcasts.
- Need for filtering: How much filtering the source approximately needs to make it look good. Rated with stars from 1 to 5, with the exception of CR's Ano Natsu de Matteru and Brave10, which get six stars for being so bad that they should just be thrown to the garbage bin. Does not take the color difference into account – for the more severe cases you can add at least one star into this for the CR encodes.
|Overall quality||Sharper picture||Color difference||Need for filtering|
|New Prince of Tennis||8.5||8.2||-||X||*||-||**||**|
|Natsume Yuujinchou Shi||8.6||8.8||-||X||*||-||*||*|
|Inu x Boku SS||4.6||4.8||-||X||*||-||****||****|
|Ano Natsu de Matteru||0.0||9.2||-||X||*||-||******||**|
Individual show analysis
Update for clarification: The methodology used to determine asset / mastering resolution here is simple: Downscale the image using spline36resize() in AviSynth and upscale back to 1080p until a resolution is found where small details don't get blurred out anymore.
This technique is not perfect, though, as resizing is a lossy process. The actual source resolution may be smaller than what is written here, but when you're dealing with pre-upscaled sources like HDCAM-sourced stuff of Blu-rays, the mentioned resolutions are the lowest that can be used without losing any detail. Hopefully that will clear things out. This methodology generally will overestimate the real asset resolution, and nowadays there are techniques you can use to "reverse" upscaling in a nearly lossless manner, for example with a filter called Debilinear (which reverses bilinear upscaling).
- Another: The best CR has to offer. Sharper than the TV broadcast, with mastering / highest asset resolution being approximately 1600x900, this only really suffers from some banding and noise, along with some weird lineart damage in a few scenes. Since the Tokyo MX broadcast is two days later as well, this is easily the best video source for Another until the BDs come out. Color difference is absolutely minimal as well.
- Nisemonogatari: Similar to Another in that it has sharper picture than the TV broadcast and the highest asset resolution seems to be around 1600x900. However, the picture is notably brighter especially in the darker scenes and it suffers notably from banding and aliasing in multiple scenes. Something interesting is the fact that the lineart seems to be overall thinner (and the aliasing more prominent) in the CR version, which could suggest that they're working with a possibly newer render than the TV channels.
- New Prince of Tennis: Really surprised me with its sharpness and clarity. While the TV broadcast is slightly sharper, the CR encode beats it with less noise and general compression artefacts. Both suffer from aliasing, though. Too bad nobody besides fujoshis watch this show. Mastering / highest asset resolution seems to be around 1440x810 or so.
- Natsume Yuujinchou: One of the better-looking CR streams as well, but surprisingly the TV Tokyo broadcast fares better in detail, sharpness and gradients despite suffering from MPEG-2 compression during some faster scenes. Mastering resolution not above 1280x720.
- Fate/Zero: Has basically the same level of detail and sharpness as the Tokyo MX broadcast, with slightly less compression artifacts. The color and brightness difference is rather jarring, however, so using the TV broadcast would be overall more preferable. Background art seems to have been done at 1280x720, but lineart seems to be of higher resolution, topping at around 1600x900 as well.
- Mouretsu Pirates: The CR video is slightly blurrier than the TV broadcast, but in exchange has less compression artefacts. Some space backgrounds and CG seems to be have been rendered at around 1600x900, but the actual animation and lineart is definitely not above 1280x720.
- Inu x Boku SS: Looks noisy as hell in both the TV broadcast and the CR encode, as well as being quite a bit more cropped in the latter. Mastering resolution definitely not above 1280x720. CR manages to fare a very slightly with some detail preservation, but the overcropping and blurriness makes it slightly worse than the TV broadcast.
- Brave10: An awful mess no matter which one you get. Suffers from field upscaling which CR did not fix – this is frankly unacceptable for video intended to be watched as-is by end users and couldn't even be fixed by further filtering at this point. Also suffers from notable amount of compression artifacts on both TV and CR, making this the ugliest TV source in the comparison. Mastering resolution definitely not above 1280x720.
- Ano Natsu de Matteru: Finally, the oddball of the comparison. The TV Aichi broadcast for this show is easily the least problematic video in the entire comparison – I don't think I've ever seen as smooth gradients in a TV broadcast (or a CR encode) as in this one (though there's still minor banding). The main problem with the cap is that there's some luma ghosting and noise, with the former being somewhat annoying to fix. However, CR completely dropped the ball with this show – their video is not even IVTC'd and suffers from very severe compression artifacts. It's completely beyond any fixing and looks like total ass. Mastering resolution isn't above 1280x720 but is definitely above 960x540, the resolution that J.C. Staff has mastered many of its shows in.
Thoughts and conclusions
First of all, I must apologize to CR – I've been mocking their video quality a lot in the past and saying how it's all because of their starved bitrates. However, the fact that both CR and the TV channels have very similar quality among the shows can only mean that the sources the TV channels and CR get have issues to begin with. As such, the issues aren't solely CR's fault.
I am going to instantly take my apology back, though, since after finding out how things really are, I realize that CR has done something far worse than just bitstarve their encodes – they have never bothered to try fix any of this shit. Fansubbers have been filtering their sources to fix various issues in them for years – there is literally no reason why CR couldn't do the same. CR already has to IVTC their stuff, so a framework for filtering should already exist (and they should also improve their IVTCing for certain shows). Time shouldn't be an issue either. Sure, they might be streaming 26 shows this season, but even I could filter and encode 26 shows a week with my single i7-2600k without even breaking a sweat. Just a couple encoding units with decent processors should be enough for CR's filtering and encoding needs.
The importance of filtering is even bigger for CR than it is for fansubs. If you are a legit customer of CR and watch their streams on their website, you can't apply any kind of postprocessing whatsoever, unlike with illegal downloads. As such, the video that CR puts up for their customers to watch should be as flawless as possible. Even if their bitrates still may not be enough to achieve that, they could certainly improve their video quality notably (especially for the worse cases) by doing adequate filtering on their apparently wildly-varying-in-quality sources.
The saddest fact about this whole thing is that while CR is now barely competing with TV broadcasts in quality, they could do a lot better. Just having similar quality to Japanese TV isn't enough when the western anime fanbase, in other words CR's entire audience, is used to watching filtered fansubs rather than raw unfiltered broadcasts. Maybe they wanted to one-up fansub/rip releases that stick to 720p for TV stuff. But you know what? They do that for a reason. TV broadcast quality just isn't that good, and anime mastering resolutions generally aren't high enough to make 1080p encodes from TV sources worthwhile. Considering that CR's 1080p offerings aren't really any better, it really is a shame. If they gave the bitrate of their current 1080p encodes to their 720p encodes, they could without a doubt beat the TV broadcasts in quality for pretty much all the cases. Sadly, since they're playing the number game of advertising (”bigger must always mean better, right?”), they can hardly back down from offering 1080p now. Gullible people will certainly eat that up, but what about the people who actually care about video quality and understand that there's more to it than just the resolution?
Published on 15.01.2012. The author of this post is a long-time video enthusiast, hobby compressionist and a fansubber who goes by the nickname Daiz. You can contact him at dnw142 [at] gmail [dot] com or you can leave a comment below.