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How does FFmpeg know about duplicate frames in the input stream?
FFmpeg knows about duplicate frames in the input video stream as it outputs a message like this: Is there some way to tell it: “Not include duplicates into the output stream, please?”
What kind of codec do you use for FFmpeg?
Original 2012-11-16, Updated 2016-04-05: cleanup and information about overlaying images. When using ffmpeg to compress a video, I recommend using the libx264 codec, from experience it has given me excellent quality for small video sizes.
How to create an overlay image in FFmpeg?
-start_number specifies what image to start at -vframes 1000 specifies the number frames/images in the video Assuming that you have an overlay image that is the same size as the video, you can use the following command to add it during the ffmpeg compression process. ~/path_to_overlay.png is the full/relative path to the overlay image
When do you use% 04d in FFmpeg?
where the %04d means that zeros will be padded until the length of the string is 4 i.e 0001…0020…0030…2000 and so on. If no padding is needed use something similar to pic%d.png or %d.png. -r is the framerate (fps) -crf is the quality, lower means better quality, 15-25 is usually good.
Why is it important to transcod video files?
The video conversion is really important for those who are hosting their own files and not relying on a third-party site such as YouTube or Vimeo because you are looking for the most compatible video standards that offer the best quality at the lowest bandwidth so that no only your server is happy but the users that visit your site.
How can I convert a video to FFmpeg?
This quick guide goes through some of the details on how we convert some videos using FFmpeg.
How big of a file do you need for FFmpeg?
For our test video, we shall be using something from our own site which is the Ukidig-HD.mp4 file which was recorded in dual-pass 25-35mb stream giving the maximum quality. This file is rather large at 290+ megs in size. You are welcome to download and follow along with this guide if you wish.
What does the concat demuxer do in FFmpeg?
What the concat demuxer does is add an offset to the timestamps of all files after the first one. The priming sample created in step 2 is affecting the timestamp post-offset. If you skip audio during extraction and concat, and add it only at the end, you can avoid that.
What is the setpts filter expression in FFmpeg?
The setpts filter expression generates smooth timestamps for a video at FRAME_RATE FPS. See an explanation for timestamps at What is video timescale, timebase, or timestamp in ffmpeg?