Advice about ffmpeg options to further compress video?

[yetanotherlogin]

Hello

I shot a video of a concert that I need to further compress from its original 2.7GB so I can share it with friends.

Here's the original file:

Stream #0:0[0x1e0]: Video: mpeg2video (Main), yuv420p, 720x576 [SAR 64:45 DAR 16:9], 25 fps, 25 tbr, 90k tbn, 50 tbc
Stream #0:1[0x80]: Audio: ac3, 48000 Hz, 5.1(side), s16, 448 kb/s

Sound should be preserved as much as possible, but video isn't as important.

I was thinking of using the following options to run ffmpeg (version N-46469-gc995644 on Windows):

ffmpeg -i input.mpg -c:v libx264 -vf scale=iw/2:-1 -preset faster -c:a ac3 -ab 192k output.smaller.mp4

What do you think?

Thank yoou.

[Selur]

Sound should be preserved as much as possible, ...

then don't reencode it,....

but video isn't as important.

a. denoise/smooth the video
b. use a higher crf value or use 2pass and lower the bitrate
c. use a slower preset

alternatively simple share just the audio,...

[yetanotherlogin]

Thank you.

Can FFmpeg do this? If yes, how?

[Selur]

http://ffmpeg.org/ffmpeg.html

• as denoiser, ffmpeg has hq3n3d -> http://ffmpeg.org/ffmpeg-filters.html#hqdn3d
  so in example: "-vf hqdn3d" will use the default values
• a slower x264 preset can be chosen through: -preset X
  X can be: ultrafast, superfast, veryfast, faster, fast, medium (which is like removing -preset X), slow, slower, veryslow, placebo
• the rate factor can be changed by: -crf X
  (X is between 1 and 61, the lower the ratefactor the higher the quality -> larger file size; the default is 23, use a higher value to lower the quality and effective bitrate

[yetanotherlogin]

Thanks much. I ran this, and will see how it goes:

ffmpeg -i input.mpg -c:v libx264 -vf scale=iw/2:-1 -vf hqdn3d -preset slower -crf 24 -c:a ac3 -ab 192k output.mp4