When I read the documentation and Google for examples, it all says that you can use -SS followed by a timestamp in the format of HH:MM:SS to have ffmpeg "quickly" seek to that portion of the file and start processing it there.
So if I enter the command;
ffmpeg -ss 00:03:00 -i input.mp4 output.mp4
It should quickly go through the video to the 3 minute mark, and start processing it from there.
Well, it processes it from the time I specify, but getting to that point is no faster than processing the file from the start.
In other words;
ffmpeg -ss 00:03:00 -i input.mp4 output.mp4
takes the same amount of time as;
ffmpeg -i input.mp4 output.mp4
The only difference being that the first one won't include the first three minutes in the output file.
What am I doing wrong?
Try StreamFab Downloader and download from Netflix, Amazon, Youtube! Or Try DVDFab and copy Blu-rays! or rip iTunes movies!
+ Reply to Thread
Results 1 to 3 of 3
Thread
-
-
Nothing wrong.
Starting from the beginning is basically instantaneous (maybe a few ms latency) , but you want it faster than "instantaneous?"
To help you understand, compare with the the "slow" method , and then you will understand. The "slow" method decodes all frames up to that point. Put -ss after the -i, instead of before
ffmpeg -i input.mp4 -ss 00:03:00 output.mp4 -
It seems I was following a bad example from the web, and I misunderstood what was happening.
As a test, I was trying to extract just one minute of video from the three minute mark to the four minute mark, and it was always processing four minutes. The problem was that I was using -t to specify the end time, rather than -to. So I was telling it to extract four minutes of video, but since I thought I had told it to stop at the four minute mark, it looked like it was just processing all the video up to that point.
I only briefly looked at the output videos and didn't notice that they were four minutes long. I was just testing the switches to see how they worked before trying to use them for what I really want to do, so when it looked like it wasn't working, I didn't go any further with it.
So long story short, it was me using the wrong switch.
Similar Threads
-
batch that test if the video part or audio part exist
By marcorocchini in forum Newbie / General discussionsReplies: 0Last Post: 20th Jul 2022, 08:06 -
ffmpeg fade out beginning & end of video without re-encoding middle part ?
By DonSeenu in forum Video ConversionReplies: 4Last Post: 28th Sep 2021, 03:00 -
[FFMPEG] Is there a way to remove this part that FFMPEG puts in the meta?
By GEOLINK in forum Newbie / General discussionsReplies: 2Last Post: 1st Feb 2021, 17:51 -
Erros through the editing process with ffmpeg
By ghostrewel in forum EditingReplies: 0Last Post: 12th Oct 2019, 08:14 -
ffmpeg downloads only part of video
By repsol1976 in forum ffmpegX general discussionReplies: 8Last Post: 26th Feb 2019, 03:05