Starting to copy takes long
I want to copy a little bit of a video. I do this with: ffmpeg -i input.mov -ss 16:28 -t 5 output.mov But it takes about 2:20 before the copying starts. Is this normal? -- Cecil Westerhof Senior Software Engineer LinkedIn: http://www.linkedin.com/in/cecilwesterhof
2017-03-29 1:54 GMT+02:00 Cecil Westerhof <Cecil@decebal.nl>:
I want to copy a little bit of a video. I do this with: ffmpeg -i input.mov -ss 16:28 -t 5 output.mov
But it takes about 2:20 before the copying starts. Is this normal?
Try moving the -ss part before your input. -ss before an input use forward (if possible fast forward) on your source, while before an output it means processing everything before, then start using the output after the given time.
On 2017-03-29 02:04, Cley Faye wrote:
2017-03-29 1:54 GMT+02:00 Cecil Westerhof <Cecil@decebal.nl>:
I want to copy a little bit of a video. I do this with: ffmpeg -i input.mov -ss 16:28 -t 5 output.mov
But it takes about 2:20 before the copying starts. Is this normal?
Try moving the -ss part before your input. -ss before an input use forward (if possible fast forward) on your source, while before an output it means processing everything before, then start using the output after the given time.
Furthermore ffmpeg is not copying anything there. You did not tell ffmpeg to copy. It is encoding with (probably rubbish) defaults.
On Wednesday 29 Mar 2017 02:32 CEST, James Darnley wrote:
On 2017-03-29 02:04, Cley Faye wrote:
2017-03-29 1:54 GMT+02:00 Cecil Westerhof <Cecil@decebal.nl>:
I want to copy a little bit of a video. I do this with: ffmpeg -i input.mov -ss 16:28 -t 5 output.mov
But it takes about 2:20 before the copying starts. Is this normal?
Try moving the -ss part before your input. -ss before an input use forward (if possible fast forward) on your source, while before an output it means processing everything before, then start using the output after the given time.
Furthermore ffmpeg is not copying anything there. You did not tell ffmpeg to copy. It is encoding with (probably rubbish) defaults.
You are right. But it was only a temporary hack, because what I really wanted was: ffmpeg -ss 16:28 -t 5 -i input.mov output%03d.jpg But because I had the -ss and -t on the wrong place it took very long. So I cut the piece I wanted to get the images from. (But in the wrong way.) Next time I should be more carefull. -- Cecil Westerhof Senior Software Engineer LinkedIn: http://www.linkedin.com/in/cecilwesterhof
2017-03-29 4:17 GMT+02:00 Cecil Westerhof <Cecil@decebal.nl>:
You are right. But it was only a temporary hack, because what I really wanted was: ffmpeg -ss 16:28 -t 5 -i input.mov output%03d.jpg
Just like to note that the input option "-t" is supposed to work but sometimes has side-effects (or fails), the safe way to do it is: $ ffmpeg -ss x -i input -t y out unless you need the input option. Carl Eugen
On Wednesday 29 Mar 2017 09:34 CEST, Carl Eugen Hoyos wrote:
2017-03-29 4:17 GMT+02:00 Cecil Westerhof <Cecil@decebal.nl>:
You are right. But it was only a temporary hack, because what I really wanted was: ffmpeg -ss 16:28 -t 5 -i input.mov output%03d.jpg
Just like to note that the input option "-t" is supposed to work but sometimes has side-effects (or fails), the safe way to do it is: $ ffmpeg -ss x -i input -t y out unless you need the input option.
In this case it worked, but when I need it again, I will put it after the input. -- Cecil Westerhof Senior Software Engineer LinkedIn: http://www.linkedin.com/in/cecilwesterhof
On Wednesday 29 Mar 2017 02:04 CEST, Cley Faye wrote:
2017-03-29 1:54 GMT+02:00 Cecil Westerhof <Cecil@decebal.nl>:
I want to copy a little bit of a video. I do this with: ffmpeg -i input.mov -ss 16:28 -t 5 output.mov
But it takes about 2:20 before the copying starts. Is this normal?
Try moving the -ss part before your input. -ss before an input use forward (if possible fast forward) on your source, while before an output it means processing everything before, then start using the output after the given time.
That was the problem. Thanks. -- Cecil Westerhof Senior Software Engineer LinkedIn: http://www.linkedin.com/in/cecilwesterhof
participants (4)
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Carl Eugen Hoyos -
Cecil Westerhof -
Cley Faye -
James Darnley