What is X264?

x264 (pronounced "em-chang") is a free and open source video encoder. It is used by many open source video platforms such as ffmpeg, handbrake, gstreamer, etc.

X264 is an application software download for Windows operating systems and is released under the GNU General Public License (GPL). It offers best-in-class performance, compression, and features. It achieves dramatic performance, encoding 4 or more 1080p streams in real-time on a single consumer-level computer.

Quality is one of the most important factors for streaming video and is usually dictated by the encoder you use. The choice of encoder is crucial to the quality of your stream, but it also affects the hardware used by OBS to render the video.

AMF and NVENC are two popular alternatives to x264. NVENC uses a dedicated graphics processing unit (GPU) to perform video processing, while AMF uses the CPU. AMF tends to produce better quality than NVENC, however NVENC has the advantage of requiring less CPU power.

NVENC is generally a good option for users with AMD GPUs and a good enough CPU, as it produces higher quality video than AMF. NVENC is also a great alternative for people on lower-end PCs, as it will run faster and use fewer resources.

Using threads to encode in parallel on multiple CPUs is a very powerful feature, as it can increase encoding speed linearly with the number of CPU cores. You can manually select the number of threads to be created or, if you set threads=auto, x264 will pick an appropriate number of threads based on how many CPUs are available.