: Constant Rate Factor. Lower values (e.g., 18-20) mean higher quality; higher values mean smaller files. Experts advise using CRF over bitrate for one-pass web encodes.
ffmpeg -i input.mp4 -c:v libx265 -crf 23 -preset medium -movflags +faststart -c:a aac -b:a 128k output.mp4 Use code with caution. Copied to clipboard x265-web
: Controls the trade-off between encoding speed and compression efficiency. For the web, medium or slow is typically best. : Constant Rate Factor
: If authoring for Apple devices via HLS, ensure you meet the HLS Authoring Specification which requires HEVC for specific UHD variants. 18-20) mean higher quality
: Using 10-bit color ( -pix_fmt yuv420p10le ) can significantly reduce "banding" in gradients (like skies), even for 8-bit sources. 3. Why Use x265-Web?