Privacy Policy

Welcome to our website. To help you use our services with confidence, we explain our privacy policy below to safeguard your rights. Please read the following information carefully:

Scope of the Privacy Policy: This privacy policy applies to all personal data collected by this website, including how we collect, process, and use such data when you use our services. This policy does not apply to other linked websites or personnel not managed by this website.
Collection, Processing, and Use of Personal Data: When you visit our website or use our services, we may ask for necessary personal information, which will be processed and used only for specified purposes. Without your written consent, we will not use your personal data for other purposes.
Legal Basis for Processing Data: We process your personal data based on your consent, to fulfill contractual obligations, or for our legitimate business interests, such as enhancing user experience or conducting analysis.
Data Protection: We adopt multiple security measures to protect your personal data, including firewalls and antivirus systems. Only authorized personnel can access your data, and they must sign confidentiality agreements. When we outsource services, we require that they comply with confidentiality obligations and ensure data security.
External Links: Our web pages may contain links to external websites. These linked websites do not fall under our privacy policy, and you should refer to their respective privacy policies.
Sharing Personal Data with Third Parties: We do not provide, exchange, rent, or sell your personal data to third parties, except as required by law or contractual obligations. We may share your data under the following circumstances:
- With your written consent.
- As required by law.
- To protect your life, body, freedom, or property from danger.
- For statistical or academic research with public institutions or academic research organizations, ensuring data is anonymized.
- When your actions on the website violate the terms of service, necessitating identification, contact, or legal action.
Data Retention: We retain personal data only for as long as is necessary to fulfill the purposes outlined in this policy, or as required by law. When the retention period ends, we delete or anonymize the data to ensure privacy.
Your Rights: Under applicable privacy laws, you have the right to request access to your personal data, correct inaccuracies, request deletion of your data, object to processing, and request data portability. You also have the right to lodge a complaint with a supervisory authority.
Use of Cookies: To provide you with the best service experience, we use cookies on your device. If you do not wish to accept cookies, you can increase the privacy level in your browser settings to refuse cookies. This may, however, affect the availability of certain features. You can also manage your cookie preferences through our Cookie Settings.
Privacy Policy Revisions: We may revise the privacy policy as needed, and any changes will be published on this website to ensure you are informed of how we handle your personal data.

H.265 與 H.264 比較

H.265 與 H.264 比較

H.265 又稱為高效率視訊編碼，英文名 High Efficiency Video Coding，簡稱 HEVC，是 MPEG-H 第 2 部分，是一種視訊壓縮標準，被視為是 ITU-T H.264/MPEG-4 AVC 標準的繼任者。2004 年開始由 ISO/IEC Moving Picture Experts Group (MPEG) 和 ITU-T Video Coding Experts Group (VCEG) 作為 ISO/IEC 23008-2 MPEG-H Part 2 或稱作 ITU-T H.265 開始制定。第一版的 HEVC/H.265 視訊壓縮標準在 2013 年 4 月 13 日被接受為國際電信聯盟 (ITU-T) 的正式標準。HEVC 被認為不僅提昇影像品質，同時也能達到 H.264/MPEG-4 AVC 兩倍之壓縮率，等同於同樣畫面品質下位元率減少到了 50%，可支援 4K 解析度甚至到超高畫質電視 (UHDTV)，最高解析度可達到 8192×4320 (8K 解析度)。

H.265/HEVC 的編碼架構，大致上和 H.264/AVC 的架構相似，主要也包含：幀內預測(intra prediction)、幀間預測(inter prediction)、轉換(transform)、量化(quantization)、去區塊濾波器(deblocking filter)、熵編碼(entropy coding)等模組。但在 HEVC 編碼架構中，整體被分為了三個基本單位，分別是：編碼單位(coding unit,CU)、預測單位(predict unit,PU) 和轉換單位(transform unit,TU )。

H.265 標準圍繞著現有 H.264 的影像編碼標準，保留原來的某些技術，同時對一些相關的技術加以改進。新技術使用先進的技術，用以改善碼流、編碼品質、延時和演算法複雜度之間的關係，達到最優化設置。具體的研究內容包括：提高壓縮效率、提高魯棒性(指系統在擾動或不確定的情況下仍能保持它們的特徵行為)和錯誤恢復能力、減少即時的時延、減少通道獲取時間，和隨機接入時延、降低複雜度等。

相比 H.264/AVC，先進的 H.265/HEVC 提供了更多不同的工具，來降低碼率，以編碼單位來說，H.264 中每個宏塊(marcoblock,MB) 大小，都是固定的 16x16 像素，而 H.265 的編碼單位，可以選擇從最小的 8x8，到最大的 64x64。所以，H.265/HEVC 的編碼效率優於 H.264/AVC。

值得注意的是 H.265/HEVC 的壓縮優勢只有在高解析度，例如 4K/8K 場合有用。同樣是 FHD 1080P，其實 H.264/AVC 與 H.265/HEVC 的差異沒有像 4K/8K 顯著。對於一般 1080P 的影片來說，以 H.264/AVC 技術壓縮後已有不錯的效果，但在解析度 4K 或以上的高畫質影片時，可能稍顯不足，相較於 H.264/AVC，使用 H.265/HEVC 在相同畫質下，壓縮率較 H.264/AVC 高了一倍以上，也使的 4K 畫質影片得以普及於各大串流平台。