概述
本指南比较 H.264 (AVC) 和 H.265 (HEVC) 在最重要的标准上，以帮助您选择适合您需求的格式。
H.265 提供比 H.264 高 50% 的压缩率，但需要更多的处理能力，并且支持的设备较少。
Head-to-Head Comparison
Compression
H.264 (AVC): H.264 效率较低，但编码/解码时使用的 CPU 较少。
H.265 (HEVC): H.265 在相同质量下实现 50% 更小的文件。
Winner: H.265
兼容性
H.264 (AVC): H.264 被所有设备、浏览器和平台支持。
H.265 (HEVC): H.265 需要现代硬件 - 较旧的设备可能不支持。
Winner: H.264
CPU 使用率
H.264 (AVC): H.264 在所有硬件上，包括较旧的 CPU，解码都很容易。
H.265 (HEVC): H.265 需要现代硬件以实现流畅解码。
Winner: H.264
4K 视频
H.264 (AVC): H.264 可以处理 4K，但文件非常大。
H.265 (HEVC): H.265 是 4K 和 HDR 视频的标准编解码器。
Winner: H.265
流媒体
H.264 (AVC): H.264 是通用的流媒体标准（YouTube、Netflix 都使用这两者）。
H.265 (HEVC): H.265 正越来越多地用于高质量流媒体。
Winner: 平局
Technical Foundations
H.265 (HEVC, High Efficiency Video Coding) is the successor to H.264 (AVC, Advanced Video Coding), both developed jointly by ITU-T and ISO/IEC.[1][2] The largest structural change is the coding block: where H.264 partitions frames into fixed 16x16 macroblocks, HEVC uses flexible coding tree units up to 64x64 that can be recursively subdivided, letting the encoder allocate bits efficiently across both large flat regions and fine detail.[1] HEVC also adds more intra-prediction directions and improved motion compensation and entropy coding.
Compression Efficiency
These tools let HEVC achieve approximately the same subjective quality as H.264 at substantially lower bitrates, with figures commonly cited around a 50 percent bitrate reduction, at the cost of significantly higher computational complexity for both encoding and decoding.[2] HEVC was designed with high resolutions in mind and scales efficiently to 4K and 8K, where H.264's older toolset becomes less economical.[1]
Both Are Codecs, Not Containers
H.264 and H.265 define how video is compressed, not how it is stored as a file. Streams encoded with either codec are placed inside a container such as MP4, MKV, or MOV, which adds audio, subtitles, and timing.[2] The same codec can appear in different containers, and a container can hold either codec, which is why a file's extension does not indicate which codec it uses.
Licensing and Hardware
A practical difference is patent licensing. H.264 has a mature, widely-accepted licensing framework and near-universal hardware decode support.[2] HEVC's licensing is administered across multiple patent pools, which has slowed its adoption on the open web and contributed to the development of royalty-free alternatives such as AV1.[1] Hardware HEVC decoding is common on modern devices but less universal than H.264.
Compatibility and Applications
H.264 remains the most universally supported video codec, decodable by virtually every device and browser, making it the safest choice for broad distribution.[2] H.265 is used where bandwidth or storage savings at high resolution justify its heavier processing and licensing, such as 4K streaming, modern broadcast, and recent mobile-device video capture.[1]