Difference between revisions of "Ffmpeg"
From Wasya Wiki
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ffmpeg -i <input>.mp4 <output>.webm | ffmpeg -i <input>.mp4 <output>.webm | ||
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You might want to use the -ss and -t options to create short test encodes. -ss being the start time and -t being the duration — both in seconds. You probably don’t need to encode the entire video to determine what’s acceptable. | You might want to use the -ss and -t options to create short test encodes. -ss being the start time and -t being the duration — both in seconds. You probably don’t need to encode the entire video to determine what’s acceptable. | ||
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| + | === crf === | ||
| + | * 0 = lossless | ||
| + | * 18 = visually lossless | ||
| + | * 23 = default | ||
| + | * 28 = sane low quality | ||
| + | * 51 = worst quality possible | ||
| + | * The range is exponential, so increasing the CRF value +6 results in roughly half the bitrate / file size, while -6 leads to roughly twice the bitrate. | ||
| + | |||
| + | === Common Sizes === | ||
| + | * 960x540 horizontal (540x960 vertical) | ||
| + | * 640x360 | ||
| + | * 512x288 (288x512) | ||
| + | * 340x202 | ||
Revision as of 19:16, 20 March 2022
ffmpeg -i <input>.mp4 <output>.webm
ffmpeg -i MVI_0083.MP4 -s 960x540 -crf 18 20190322_out.webm ffmpeg -i MVI_0083.MP4 -s 960x540 20190322_out.mp4 ffmpeg.exe -i "test.avi" -c:v libx264 -crf 20 -c:a aac -strict -2 "test.mp4"
You might want to use the -ss and -t options to create short test encodes. -ss being the start time and -t being the duration — both in seconds. You probably don’t need to encode the entire video to determine what’s acceptable.
crf
- 0 = lossless
- 18 = visually lossless
- 23 = default
- 28 = sane low quality
- 51 = worst quality possible
- The range is exponential, so increasing the CRF value +6 results in roughly half the bitrate / file size, while -6 leads to roughly twice the bitrate.
Common Sizes
- 960x540 horizontal (540x960 vertical)
- 640x360
- 512x288 (288x512)
- 340x202
