The CPU usage may come up to 90%-100% while decoding H.264, let alone HEVC codec. This also poses a big challenge on the CPU since video encoding/decoding refers to computer-intensive operations. Codec: 4K footages are commonly encoded in H.264 or HEVC/H.265 for a higher compression rate.Frame rate: The mainstream frame rate of 4K reaches up to 60fps (optimally for HDR 10bit file), resulting in twice bigger and faster storage than 30fps indirectly.The more data required for recording to fill up the larger 4k resolution, the bigger it becomes and more space is taken up.

Bitrate: Cameras generally record 4k resolution files at a higher bit rate, averagely 100-200Mbps for inter-compression.

Resolution: 4K refers to a resolution of 3840x2160 in consumer media or 4096x2160 in the movie projection industry, yielding 4 times more bulky than traditional HD content in terms of file size.

Prior to this, please get to know the very basic video specs relevant to 4k UHD, which may be the real culprit for diversified 4K video errors.

Black bars - Why does my 4k content show black bars? Quality - Instagram/Youtube reduces 4K video quality. Big file size - 4K is too big, it stuck uploading. Frame drops - Frame drops when playing 4K 60fps video. HDR - 4K 10bit HDR video looks washed out. Quality - Green and pink video during editing. Choppy - Jerky or stuttering 4k video playback, how to fix? Codec/format - Video taken by camera cannot be imported. VFR - Audio and video are out of sync in editors. 4k split - Why do cameras split 4K into segments? 12 Common Problems with 4k Video Playing, Editing, and Uploading

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