> Am 11.10.2019 um 07:51 schrieb Anand Veerappan <anandz...@gmail.com>:
> While encoding a video file using FFmpeg we have option to handle thread > parameter. I used Quad Core Processor and find below my observations. > > *Case 1: Default thread usage* > By default if we didn't specify thread value FFmpeg internally adjusts > thread count usage based on the core architecture of the deployment machine. > > Example: > > ffmpeg -i football_1080p.mp4 -c:v libx264 -b:v 3M -bufsize 6M -maxrate > 4.5M -g 120 -tune psnr -report football_1080p_3M_threads_1_p.mp4 libx264 defaults to using as many threads as the system provides cores iirc (this is not really FFmpeg-related). > If I repeat this command n times for encoding always the encoded file size > is similar in all iterations. But - as you found out - this is not true in general. The fact that multi-threaded encoding can lead to different output is not related to FFmpeg or libx264 but a property of multi-threaded computing in general (you can of course implement the multi-threading with a synchronisation to achieve identical results but in the case of video encoding this additional complexity that leads to a lower encoding speed is not wanted). Carl Eugen _______________________________________________ ffmpeg-user mailing list email@example.com https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".