「當藝術不斷挑戰科技的同時，科技也在啟發著藝術 (Art challenges technology, and technology inspires art)。」皮克斯動畫工作室創始成員之一約翰·拉塞特 (John A. Lasseter) 曾經這麼說過。這種既相輔相成，彼此互相啟發與影響的關係，也發生在人類需求與科技發展之間。每當有新科技被發展出來解決了某個人類需求後，身為人類的我們，總是可以把對這個需求的要求拉得更高，不然就是創造出另一個全新的需求。

As Pixar’s John Lasseter once said, “Art challenges technology, and technology inspires art” [27]. Through our work with clients, we have observed some legacy issues, as new challenges, in the video streaming industry, and we would like to share two of them here.

將近十年的期間，在提供影音串流技術來服務客戶的過程中，我們也注意到了一些難題：一些原以為已經被解決掉的舊有需求，它們再次以新的樣貌出現，或是同樣樣貌但不同情境的方式出現。它不再只是當初的簡單技術問題。這邊，來一起看看其中的兩個難題：

影像畫質與傳輸頻寬之間的糾葛

要好的畫質？沒問題，那我們就提高網路頻寬的使用量吧。要低延遲？沒問題，那我們就降低畫質吧。要省網路費？沒問題，那我們就降低網路用量吧。什麼都想要？也沒問題，那就花多一點錢在網路設施上，或是換上新穎的影音編碼，或是只留在網路品質好的市區裏頭吧。畫質、延遲、體驗、頻寬、費用…彼此既互相牽制抗衡，又彼此扶持。

雖然我們會有更快更低延遲的 5G 網路，我們也會有更新穎，壓縮率更好的影音編碼技術，但就如同前述，我們對畫質的要求也提高了，對延遲更沒有耐心了，對播放順暢度更計較了，對很多細節更加吹毛求疵了。另一方面，即使 5G 與新的影音編碼普及了，那個時候我們想看的，可能是 4K 多視角的直播，是 8K 的立體電影，是更即時的高畫質 PS6 遊戲畫面了…

內容保護授權與內容散播成效之間的兩難

「畫面上的每一個像素都是專家努力和高科技計算的體現 (every pixel counts)。」一句常見於特效產業與電腦動畫產業的話，指的是在影音產業裏，產出的量化是可以細微到以像素為單位來計算的的。換個說法，這些高畫質影音的生產成本很高，它是高成本的產物，它被預期要帶來高產值，它需要被有效的控管使用權與觀賞權。

好萊塢與科技大廠的合作下，促成了數位內容管理與保護機制 (DRM) 的誕生與普及。某個程度上，DRM 它也的確很稱職的做著它被期待的任務：保護、管控、授權。但 DRM 也帶來了不少麻煩，其中之一是 DRM 對於播放的軟硬體有更多的限制，也導致更多的播放問題。換句話說，DRM 讓播放器變得更容易出包，你更容易在一些奇怪場合下看到播放器掛掉了…

Quality vs. Bitrate

There is always a trade-off between video quality and video bitrate. The higher the quality demanded, the higher the bitrate required, which can lead to the worse streaming experience.

According to some reports, the world is entering the 5G era, which could potentially lead to stronger networking infrastructure and a better streaming environment [28]. However, it is important to note that 5G is still in its early stages and many 5G services have not yet reached their full potential. Access to 5G is currently limited to a few specific regions, with much of the world still relying on 4G or even 3G networks. Additionally, even when 5G becomes more widely available, it is likely that new services will be developed that will continue to put strain on networking bandwidth, such as 4K multi-view streaming, 8K streaming, real-time high-frame-rate game streaming, or 360 VR streaming.

Protection vs. Penetration

In the visual effects and animation industry, the saying “every pixel counts” is a reminder of the effort that goes into creating high-quality movies or episodes. This process involves rendering pixels, frames, shots, and sequences, all of which contribute to the final video. To make the streaming of such high-budget premium content feasible and robust, technology companies often partner with software and hardware firms to incorporate digital rights management (DRM).

DRM functions quite well, or at least, well enough to some extent, except one drawback: it raises the difficulty of a video streaming’s playback. That is, DRM generates playback issues when there is something wrong during the overall trust-building process. So there is always an argument with video protection and video penetration.

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