barcodehaa.blogg.se - Ffmpeg cut video sync audio

We should note that re-encoding takes time depending on the size and the type of codec used. Moreover, to limit errors, we should avoid adding lots of keyframes. Therefore, we forced FFmpeg to add keyframes at the first and last frames to ensure we encode a perfect clip. However, if the first frame is not a keyframe, then the frames before the first keyframe in the clip will not be playable. We used the -force_key_frames option because video clipping occurs at keyframes.

Finally, it will carry out an audio correction to match the timestamp and re-encode the video with the original my_video.mp4 codec.Īlternatively, if we need a more time-accurate cut, we can manually add the keyframes to the start and end of the clipped video: $ ffmpeg -i my_video.mp4 -force_key_frames 00:00:15,00:00:25 clip.mp4 The value of -t is added to the sought timestamp, which is 15 seconds. The command above will process the my_video.mp4 input file and seek 15 seconds forward in the video. The value 1 will correct the start of the stream without any later correction.

The -async option specifies whether to contract or stretch the audio to match the timestamp.

The -t argument is used to specify the duration of the clip.

The -ss argument seeks to the timestamp specified as the argument.

The -i argument is used for specifying input files.

Now, let’s review each of the options and arguments we used here: Video:5132kB audio:157kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.167893% The command combines multiple MTS file and a mp3 file and produces a combined synchronized MTS file.$ ffmpeg -i my_video.mp4 -ss 00:00:15 -t 00:00:10 -async -1 clip.mp4įrame= 250 fps= 19 q=-1.0 Lsize= 5297kB time=00:00:09.98 bitrate=4346.5kbits/s speed=0.767x

Run Sync1.bat to run a ffmpeg command.

Click Save to save SyncX.bat on the directory with the current Start position.

You can enable or disable the audio playback with the Video and Audio checkboxes.

Ctrl-Left or Right shifts the Audio relative to the Video.

Shift->Left or Right changes the zoom level.Change the starting position using the Left or Right key.

Click Open and select multiple files using Ctrl and Shift keys: GroupX.mp3, GroupX_0.MTS, GroupX_1.MTS.

Using left and right arrow keys with the combination of Ctrl and Shift keys, users can zoom in and out and shift the audio relative to the video.

This application reads multiple MTS (common camcorder recording format) and a MP3 file using FFMPEG library and and present them as wave forms for easier alignment. So, it is necessary to synchronize the video with the audio. For high audio quality, sound is separately recorded with an audio recorder when video is taken.