Optimizing Video Compression with ffmpeg and hevc_nvenc

ffmpeg -i fileName.mp4 -c:v hevc_nvenc -preset slow -rc:v vbr -cq:v 24 -b:v 0 -c:a aac -b:a 128k -vf scale=1280:-1 -movflags +faststart fileName_compressed.mp4

Flag	Explanation
-i fileName.mp4	Specifies the input file as fileName.mp4
-c:v hevc_nvenc	Sets the video codec to NVIDIA’s HEVC encoder
-preset slow	Sets the encoding preset to “slow” for better compression efficiency
-rc:v vbr	Sets the rate control mode to variable bitrate
-cq:v 24	Sets the Constant Quality (CQ) value to 24 (lower values mean higher quality)
-b:v 0	Sets the target bitrate to 0, allowing CQ mode to determine the bitrate
-c:a aac	Sets the audio codec to AAC
-b:a 128k	Sets the audio bitrate to 128 kbps
-vf scale=1280:-1	Scales the video width to 1280 pixels, height scaled proportionally
-movflags +faststart	Optimizes the file for web streaming, allowing faster video startup
fileName_compressed.mp4	Specifies the output filename

smaller:

ffmpeg -i 1.mp4 -c:v hevc_nvenc -preset slow -rc:v vbr -cq:v 29 -b:v 450k -c:a aac -b:a 96k -vf scale=960:-1 -movflags +faststart 2.mp4