What should I do if I don't have enough bandwidth after playing the 4K original disc? I believe many people have considered using the CPU's integrated graphics card to perform online transcoding. This article collects and organizes some information on hardware-accelerated online transcoding.
The best three platforms for NAS are Jellyfin, Emby, and PLEX. Jellyfin is an open-source version separated from Emby, and both Emby and PLEX require payment.
The three platforms have their own unique poster walls and decoding/transcoding functions. The supported hardware list will be analyzed and organized one by one.
Concept Introduction#
What is video transcoding?#
A simple introduction:
Video transcoding is the process of converting a compressed and encoded video stream into another video stream to adapt to different network bandwidths, different terminal processing capabilities, and different user needs. Transcoding is essentially a process of decoding and then encoding, so the resulting stream may or may not follow the same video encoding standard.
Source: Baidu Baike
Why do we need video transcoding?#
It is not necessary for the local network. Your NAS only needs to be responsible for transmission within the local network. The decoding work is handled by devices such as TV boxes, phones, tablets, and computers. This process is called decoding.
When you are outside the network and want to watch 4K or high-quality videos in your NAS, your bandwidth may not be sufficient. At this time, transcoding can greatly reduce bandwidth consumption. Maybe your bandwidth is sufficient (such as my tested 500M Down/40M Up from China Telecom, which can smoothly play 4K H265 on one client), but one client cannot handle 2 or more concurrent users. Online transcoding becomes particularly important.
What is the difference between video transcoding and decoding?#
Video transcoding and video decoding are not the same concept, nor do they have the same meaning.
Video transcoding is done by the server. The server only needs to provide the client with what the client needs to play (the image quality is influenced by the server).
Video decoding is done by the client. The server transmits the original data to the client as it is, and the client needs to render it to display the output (the quality of the original film depends on how it is decoded).
Emby Section#
According to the documentation provided by the Emby official website:
Emby supports a wide range of hardware-accelerated video transcoding methods on its supported platforms:
Windows
- Nvidia NVDEC and NVENC
APIs for video encoding and decoding acceleration using Nvidia GPUs - Intel QuickSync Video
Intel's dedicated video encoding and decoding hardware core - AMD AMF
AMD Advanced Media Framework - multimedia API for real-time multimedia processing on AMD hardware - Microsoft DXVA
Microsoft DirectX Video Acceleration API - hardware-accelerated video decoding independent of hardware
Linux
- Nvidia NVDEC and NVENC
APIs for video encoding and decoding acceleration using Nvidia GPUs - VA API
Video Acceleration API supported by multiple device manufacturers for Linux - Intel QuickSync Video
Intel's dedicated video encoding and decoding hardware core
Android
- Android MediaCodec
MediaCodec is a professional API for video decoding on Android. - OpenMax
OpenMax is an API specification that covers various aspects of media acceleration. On Android, it is the standard API for codec implementation, and applications usually use MediaCodec.
Hardware Support List#
Nvidia NVDEC Support List#
Video Encode and Decode GPU Support Matrix Direct Link
Intel QuickSync Video#
Intel QuickSync Video technology can only be checked step by step through the ARK to see if there is a QuickSync Video support option in the detailed information.
Product Specifications Direct Link
AMD AMF#
No comprehensive support list was found. There is a link to obs-amd-encoder Direct Link
Microsoft DXVA#
Similarly, you can only check step by step through the ARK to see if there is a DXVA support option in the detailed information.
Product Specifications Direct Link