[VCB-Studio] 丹特丽安的书架 / Dantalian no Shoka / ダンタリアンの書架 10-bit 1080p HEVC BDRip [Fin]
簡介: 丹特丽安的书架 / Dantalian no Shoka / ダンタリアンの書架 BDRip 部分剧集内封评论音轨。 Certain episodes contain commentary tracks. 整体画质极差，简单来说，出现了 BD 及 DVD 原盘可能出现的几乎所有问题。更为棘手的是，许多瑕疵并非持续存在，而是间歇性出现，这进一步增加了处理的难度与复杂度。 The overall image quality is very poor. Basically, it has almost every artifact you could find in BD and DVD sources. The situation is especially tricky because many artifacts come and go. This makes the cleanup much harder and more complex. 原盘（含特典）主要瑕疵汇总如下：强色带、二值化锯齿、缩放锯齿、振铃、色块、烂边、蚊噪、亮度越界、多种交错类型、色度色带、色度锯齿及色度偏移。此外，如何在保留噪点观感与控制体积之间寻求平衡，也是处理难点之一。 The main artifacts in the source (including bonus videos) are: strong banding, binarized aliasing, scaling aliasing, ringing, blocking, dirty edges, DCT noise, luma overflow, several types of interlacing, chroma banding, chroma aliasing, and chroma shift. Another challenge was balancing the need to keep the grain-looking natural while keeping the bit-rate reasonable. 下面详述几个突出问题： Below are detailed discussions of several prominent issues: 首先是色带：尽管画面整体覆盖高强度噪点，但色带问题依然严峻。原因大概率是色带在加入噪点层及编码之前，即制作流程的相对早期环节已被引入。特征为色带排列整齐，主要表现为平行的直线或曲线，部分色带在 8bit 下跨度为 2 。这种整齐明显的色带与其上覆盖的高强度噪点，给修复带来了很大的困难。此外，本片的一些背景使用了色调分离（Posterization）特效（此类“色带”为艺术效果，需尽力保留），若为去除真正的强色带而采用高强度的处理手段，会严重破坏背景细节。因此，常规去色带手段在此并不适用。经过实验，我们最终采用了一种非常规方案：组合基于神经网络的降噪模型与传统去色带方法对色带进行处理，尽可能地在最大程度去除色带的同时，保留背景风格及细节。 First is banding. Even though the whole image is covered in heavy noise, the banding is still very bad. It was probably introduced early in production, before the noise layer and before encoding. Most visible banding lines up neatly like straight or curved parallel lines, in some of which, the color value change between adjacent bands is around 2 in 8-bit, very noticeable. This clear banding under heavy noise is very difficult to fix. Also, some backgrounds use a posterization effect on purpose. This “banding” is an artistic choice and we tried hard to keep it. If strong processing methods are used to remove the actual heavy banding, background details would be severely damaged. Therefore, routine de-banding methods are not suitable here. After testing, we used a special method. We combined a neural network denoising model with standard de-banding. The goal was to remove the bad banding without harming the background's art style and details. 其次是色度平面，分两种情况处理：1-5 卷整体质量尚可，仅存在一些欠码瑕疵，我们采用了常规色度重构进行修复。第 6 卷问题较为严重，不仅存在色度偏移，色度平面也有极严重的锯齿及欠码瑕疵。对此，我们先修复了色度偏移，接下来使用两轮不同算法的色度重构，最终将色度平面修复至可接受的观感水平。 Next, the chroma planes. We treated it in two parts. For Volumes 1-5, the quality was okay, with only minor issues from lack of bitrate. We fixed these with standard chroma reconstruction. Volume 6 was much worse. It had chroma shift, very bad chroma aliasing, and other problems from lack of bitrate. We fixed the chroma shift first. Then, we did two rounds of chroma reconstruction with different methods. This brought the color quality back to a watchable level. 最后关于噪点：官方制作组似乎在有意调整不同集数的噪点强度，典型如第 6 集（不同主角的单元剧）与第 9 集（书中世界），这两集的噪点层性质与其他集数相当不同。此外，其余集数间噪点强度也有变化，比如前 2 集的噪点层非常强，而后面的集数（尤其是第 6 集以后）的噪点层相对弱一些。另外 ED 部分为真人实拍，噪点特性又有所不同。对此，我们进行了逐集测试，并在必要时使用了差异化的降噪参数，同时对 ED 作了独立处理。此外，考虑到前述色带问题及处理方案，我们不得不舍弃大部分原片噪点层，转而通过实时分析进行自适应噪点重构，并对噪点层进行了适度削弱及自适应降噪处理以控制体积。 Finally, about the noise. The official production seems to have changed the noise intensity between episodes. Episode 6 (side story episode with alternative protagonist) and Episode 9 (the "book world") have noise that is quite different from the rest. The noise is also stronger in the first 2 episodes and gets weaker after Episode 6. The live-action ED has its own type of noise. We tested each episode separately and used different denoising settings when needed. The ED was processed on its own. Also, because of how we dealt with the banding problem, we had to remove most of the original noise. We then rebuilt a new, adaptive noise layer in real-time. We also reduced the noise a bit and used adaptive denoising to help control the bit-rate. 除了上述几点外，其他的瑕疵都用了常规方法来处理，不再赘述。 Other issues were fixed using standard methods, so we won't go into detail here. OVA 是 DVD 载体，画质一般，我们将其拉伸到 720p 同时转换到相应色域。主要进行了去色带和去振铃处理，原盘噪点质量不佳，我们将其丢弃，然后额外构建了与片源风格类似的噪点层以保持观感。 The OVA is under a DVD source with average quality. We upscaled it to 720p and converted the color space. We mainly did de-banding and de-ringing. The original noise was poor, so we removed it and added a new noise layer that matches the style of the source to keep the right look. 本次我们制作了两个版本的成品，除了常规的 HEVC 版，还有一个实验性的小体积 AV1 版。由于本片的高强度噪点问题，HEVC 版在压缩上用了比较激进的方案来尽可能减小成品体积，另外为了更好地保留色度重构的成果，本次使用了 YUV444 格式进行编码。AV1 版由于编码器限制仍然使用了 YUV420 格式，特典方面进行了极大简化，只保留了几种主要的特典视频。 We made two versions this time: a standard HEVC version and an experimental, smaller AV1 version. Because of the heavy noise, the HEVC version uses aggressive encoding settings to keep the size down. To better preserve the results of our chroma reconstruction, we encoded it in YUV444 format. The AV1 version still uses YUV420 due to encoder limits. The bonus videos are much less than HEVC version, keeping only a few main on