A Comprehensive Guide to Video Output Settings
If you're looking to enhance your streaming skills by understanding video output settings, you've come to the right place. In this guide, we'll explain each setting in a friendly and easy-to-understand way, without avoiding the technical details. Let's dive in and explore these settings together!
Output video bitrate
The output video bitrate refers to the amount of data (in bits) processed per second in your video stream. It directly affects the video quality and bandwidth usage. A higher bitrate offers better video quality but requires more bandwidth. Choosing the right bitrate is essential for striking the perfect balance between quality and performance.
GOP (Group of Pictures) size is the number of frames between two keyframes, which are reference frames used for compression. For example, if a keyframe is inserted every 1 second into a video at 30 frames per second, the GOP length is 30 frames, or 1 second. While real-world GOP lengths vary by application, it is typically in the 0.5 – 2 second range. Be mindful of selecting the right GOP size for your specific needs, as a larger GOP size could result in reduced video quality during playback. The GOP size affects video quality and file size. A smaller GOP size results in more frequent keyframes and better video quality, but at the expense of larger file sizes. Selecting an appropriate GOP size is crucial for optimizing video quality and storage requirements. If you are not sure what to set this parameter to, then our best advice is to Disable it.
Force key frames
Forcing keyframes allows you to manually create keyframes in your video stream, which can be useful for maintaining video quality during scene changes or for precise editing control. However, overusing this feature can increase the file size, so it's essential to strike a balance between forced keyframes and efficient compression. Essentially this is an alternative way to specify GOP.
Frame width & Frame height
Frame width and height represent the dimensions of your video frame, measured in pixels. These parameters affect the resolution and aspect ratio of your video. Larger dimensions deliver higher resolution, but they also require more processing power and bandwidth. Selecting the right resolution for your project is crucial for balancing video quality and streaming performance.
Slices divide your video frame into smaller sections, which can speed up video encoding and decoding processes. More slices can improve streaming performance, but may slightly decrease video quality. Finding the right number of slices is essential for optimizing both performance and quality.
Cores refer to the number of CPU cores utilized during video encoding. Using more cores can accelerate the encoding process, but overloading your CPU with too many cores could lead to performance issues. Choose the right number of cores based on your computer's capabilities and the complexity of the video stream.
A preset is a predefined set of encoding settings that balance video quality, encoding speed, and file size. Different presets offer various trade-offs, with faster presets potentially sacrificing video quality for the sake of encoding speed. Choose a preset that best suits your project's needs and your computer's capabilities.
Tuning adjusts encoder settings to optimize video quality for specific content types. It's essential to select the right tune based on the nature of your video content, as the wrong choice might result in suboptimal video quality. Some common tuning options include film, animation, and grain.
CRF (Constant Rate Factor)
CRF is a parameter that helps maintain consistent video quality throughout your stream by adjusting the output bitrate dynamically. Lower CRF values yield higher quality but larger file sizes, while higher CRF values result in lower quality but smaller file sizes. Selecting an appropriate CRF value is critical for balancing video quality and storage requirements.
Pixel format determines how your video's color information is stored and processed. Choosing the right format can improve video quality, but it may require more processing power. Some common pixel formats include YUV420, YUV422, and YUV444. Select a pixel format that offers the best balance between video quality and processing requirements.
Frame Rate & Output FPS
Frame rate refers to the number of video frames displayed per second (FPS) and directly affects the smoothness of your video. Higher frame