How to encode with x265 cli

Question

I have some raw H.264 10bit videos need to convert to HEVC format, but the encoder only takes some frames (600/170000) to encode, and the video is full of noise. What is the correct way to encode those videos?

The command I used:

x265 --input video.h264 --fps 24 --input-res 1920x1080 --output video.hevc

EDIT #1: I just tried to use ffmpeg but give me following error

Truncating packet of size 24883200 to 538208
[rawvideo @ 0x1561e80] Invalid buffer size, packet size 538207 < expected frame_size 24883200 Error while decoding stream #0:0: Invalid argument

EDIT #2: ffmpeg cmd

 ffmpeg -f rawvideo -vcodec rawvideo -s 1920x1080 -pix_fmt yuv420p10le -i video.h264 -c:v libx265 -crf 18 -preset medium -x265-params profile=main10:level-idc=50:high-tier:vbv-bufsize=100000:vbv-maxrate=100000 video.hevc

Answer 1

Your source is neither YUV nor Y4M, going by the extension (and also the FFmpeg error you received). x265 is referring to a raw uncompressed bitstream by those extensions, not simply the pixel format. A .h264 is a raw H.264-encoded bitstream.

To use ffmpeg only, start the cmd like this:

ffmpeg -f h264 -i video.h264 -c:v libx265 ....

To use the x265 standalone encoder, use

ffmpeg -f h264 -i video.h264 -f yuv4mpegpipe - | x265 --input - --fps 24 ....