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9

Run ffmpeg -i titlefile.mp4 -vf setdar=16/9 -video_track_timescale 29971 -ac 1 newtitle.mp4 and then run concat with the new title video. Modern containers like MP4 have Presentation TimeStamps, which are denominated with reference to a timebase. So, if the timebase value is 1/500 and a frame's PTS is 200, then that tells the video player to show that ...


5

Using one of these solutions will be more efficient. That's what you've asked for. It saves you time, because there's no more need to manually sync the presentation and the voiceover. Free Solution Keynote can record a running presentation with the mic-audio. QuickTime X has also a screenrecord-feature incl. audio. Low Cost Solution Specialized ...


5

I tried kdenlive, so I'll post my findings about it as an answer. It didn't quite do the job, so I'm not going to mark this as the accepted solution. kdenlive easily imports my clips in mjpeg+pcm, and flac. And looks like it can export through ffmpeg, which is what I want. It has a feature to "set audio reference", and for other tracks, "align audio to ...


4

The professional way Professionally done, all cameras and audio recorders will have a running (SMPTE) time code, which can be configured in 'free run' mode - meaning the time counter runs regardless whether we record or not (ie, STOP mode). At the beginning of the shooting day, all recordists (cameras, audio) will sync their clocks. This is done either to ...


4

I've had my fair share of matching. C100 with 5D MK III, 5D MK III with 7D, 7D with C100, 7D with a Sony Camcorder. It's all a matter of getting two cameras that are similar in terms of resolution and how 'soft' the image is. For example, the C100 is incredibly sharp, like 4k sharp in 1080p, whereas the DSLRS I mentioned are quite soft. Although you can add ...


4

In addition to @Mulvya answer I will suggest to use not Flash, but After Effects for animation, if possible. Then you will be able to make Dynamic Link to your AE project. Than will be easier to jump between applications. But when you work with animation, you deferentially need to have voiceover first. Like in cartoon development.


4

The following worked well for me, based on the same ideas http://www.premiumbeat.com/blog/quick-trick-for-de-flickering-your-video-shots/ https://superuser.com/questions/1025794/merge-two-videos-with-transparency-in-ffmpeg It's more than a year, so I don't remember exactly how I arrived at this. The VOB was a video shot from a projected screen with ...


4

There are, in fact, several standards on audio/video or lip sync. The problem is, they can't all agree on what the acceptable error is. What is well understood is that if the audio lags the video it is less noticeable, because that is natural. Something that is further away will be seen before it is heard. In the list below, a negative number is the audio ...


3

You are looking for a Non-Linear Video Editing packages or NLE. Premiere and Final Cut Pro are two of the most popular, but they are also relatively pricy professional products. There are also many cheaper and/or free options available such as Windows Movie Maker (Windows) or iMovie (Mac). If you search for non-linear editing software or video editing ...


3

You are over thinking it. Edit a quick beep in before the audio starts on the song, play the song aloud while you are recording the drums. Hit one of your drums so that you can see and hear it quickly on the video as well. Record the audio direct from your drums and have a third track that is the microphone for the camera. The camera audio track will ...


3

You probably will not achieve a 100% perfect result with your setup. That you got them synced to a 1FPS accuracy is pretty amazing actually. Professional stereo setups use frame locking in hardware to ensure the cameras record in perfect sync. This is not possible with ordinary webcams. If you fix the recorded video in post you can get to less than 1/...


3

I have no idea if this is optimal for you, but one approach using free software would be to first determine the percentage (and direction) of drift by finding a point near the end where you can tell with some precision what the sync error is, in frames. Demux the video and audio into separate streams, using a free tool like AVI-Mux. Load the audio into ...


3

You could try processing the audio first to get it to the same speed as the video playback. Using (for example) Audacity you can apply a speed change of -0.1% (1000/1001) which is very likely the amount you're drifting by. You can change the rate without changing pitch, but if you can tolerate the very slight pitch shift you'll get slightly better results by ...


3

Short Answer Split your Video track into separate Events; Adjust the Events individually by dragging them along the timeline and stretching/expanding them; Overlap the adjacent Events so that there were no gaps; Long Answer I find one of the most valuable features of Sony Vegas its ability to split the original tracks into Events and adjust them ...


3

If the audio is primary and the visuals convey or complement the narration, then record the audio first. Use the audio timings to guide the pacing of your animations - if some demo takes longer than its oral exposition, the music should fill in there. But you can't really avoid the step where some sentences need individual adjustment or some animations need ...


3

This sounds like a perfect candidate for using multi-camera editing. You can automagically synch all the clips using their audio, and turn them into a multicam source, which lets you edit from the multiple synched cameras quickly and easily. How to do it in premiere: Select your clips in the Project panel. Then, right-click the selected clips and choose ...


3

The short answer to your question is "no". The sample rate of video is typically measured in MHz or GHz. If you have a 1080p24 signal at 8 bits per pixel, the actual frame is 2750 x 1125 pixels (according to digital test equipment manufacturer Kramer). Multiplied by a 24 fps refresh rate, this results in 74,250,000 pixels / second. Multiplied by 10 bits ...


3

You've to reset the timestamps: [1:a]atrim=start=2.52:end=1:38.0,aloop=100:7700,asetpts=N/SR/TB[audio]


3

The usual solution for this situation: -fflags +genpts It should eliminate the warning, but there's no guarantee your sync issues will be solved.


2

Yes. The companies Spatz-Tech, HDFury and Faroudja have products with that functionality in their portfolio. But there are selling restrictions in many countries.


2

There is no way to do this automatically. It has to be done manually by matching the frames together from the two videos. This can be done by placing the videos in separate overlay tracks and works for two or more videos.


2

Regarding @rich's suggestion... if you don't have Quicktime, will iMovie work instead? Or some other program? Create your Keynote presentation. Record your speaking part (separately) with an audio recording program. I recommend Audacity. It's a great free application. You can download Audacity from www.sorceforge.com among other places. You'll also want to ...


2

It should be. You might end up with impedance mismatches that have to be dealt with, so it might take a few other (relatively cheap) steps to get there (devices called pads, which bring down the level), but it should work. The quality might not be quite as good though.


2

Haha! In movies about movies you always see this clap in the beginning of a shot. The one where the take number and everything is written on with chalk. And they hold it in front of the cam and make one loud clapping noise with it. Well, if you have ever wondered what this ritual is for, congrats! You have found the problem to the solution ;-)) You get a ...


2

I know this is a very old Q, but it should be pointed out that a 'negative timecode' makes no sense. The SMPTE frame before 00:00:00:00 is 23:59:59:29. The namespace for drop frame (and non-drop) codes is already well-defined -- no need to postulate negative values. If there are systems or programs that use this notation, they should be rethought.


2

You can tell which one gets out of synch like this: Set up your camera and your phone like you usually do. Put a clock that shows seconds right in front of the camera. Then, even though this sounds boring, record yourself counting off the seconds. Synchronize the video and audio in Premiere Pro like you usually do. When they get out of synch, check whether ...


2

You can only sync video to an accuracy of a frame, or somewhere in the area of 15-40 mSec depending on frame rate. So as long as whatever you're shooting can update and refresh at least that quickly, it's not important to do much better. Even shooting a mechanical metronome will probably get you as close as anything else. The refresh rate of the display ...


2

I probably could have done a quick google search before asking. HERO3+ Black Edition may be the only currently selling supported unit, but I found that following historical products are compatible with a "3D HERO System" (which may be different from "Dual HERO System"): HD HERO Original camera HD HERO2 camera Dont know whether "3D HERO System" has ...


2

Try Blender's Video Editing. If Video and audio where recorded at the same time it will be easy to sync them, just be sure your video frame rate is correctly set in Blender and that you check synced in the video editor (at the bottom beside the time line and play, stop, etc... buttons. Don't be scared by Blender's complexity, you are not going to use any ...


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