I wish to add a frame to the end of a video just after it has been captured so I can make a timelapse video as the images are acquired.
So the idea is to take an image, use ffpmeg to make the video by adding each image just after it is aqcuired.
I've seen many questions about adding a set length of time of a logo type image or how to compile a whole bunch of single images to a video but not this.
Anyone got a good idea of what to try?
Related
I have use ffmpeg and mp4parser to add image watermark on video.
both works when video size is small like less than 5MB to 7Mb but
when it comes to large video size(anything above than 7MB or so..)
it fails and it doesn't not work.
what are the resources that helps to adding watermark on video quickly. if you have any useful resources that please let me know?
It depends on what exactly you need.
If the watermark is just needed when the video is viewed on the android device, the easiest and quickest way is to overlay the image with a transparent background over the video view. You will need to think about fullscreen vs inline and portrait vs landscape to ensure it lines up as you want.
If you want to watermark the video itself, so that the watermark is included if the video is copied or sent elsewhere, then ffmpeg is likely as fast as other solutions on the device itself. If you are able to send the video to a server and have the watermark applied there you will have the ability to use much more powerful compute resource.
I just want some confirmation, because I have the sneaking suspicion that I wont be able to do what I want to do, given that I already ran into some errors about ffmpeg not being able to overwrite the input file. I still have some hope that what I want to do is some kind of exception, but I doubt it.
I already used ffmpeg to extract a specific frame into its own image file, I've set the thumbnail of a video with an existing image file, but I can't seem to figure out how to set a specific frame from the video as the thumbnail. I want to do this without having to extract the frame into a separate file and I don't want to create an output file, I want to edit the video directly and change the thumbnail using a frame from the video itself. Is that possible?
You're probably better off asking it in IRC zeronode #ffmpeg-devel.
I'd look at "-ss 33.5" or a more precise filter "-vf 'select=gte(n,1000)'" both will give same or very similar result at 30 fps video.
You can pipe the image out to your own process via pipe if you like of course without saving it : "ffmpeg ... -f jpeg -|..."
I am stucked by a video processing feature, Specifically, upload an image and then generate a video based on various video templates.
Here are the video templates:
http://video-static.biku8.com/data/video/template/3286012076458048/7437ab55-2e83-4a36-9046-5708fcddf4c1.mp4
http://video-static.biku8.com/data/video/template/3274256089907264/ae8fa3f7-6c9c-45ca-810f-48db92cc14cb.mp4
http://video-static.biku8.com/data/video/template/3213894231425088/bf107d439b9043a58c1ea0ba26f811db_template.mp4
...
As shown in the video templates above, I just need to upload a photo to generate a great video.
My question
What is the specific idea for implementing this video?
Which third-party libraries are needed? (ffmpeg, opencv)
PS: I am using dlib and opencv for face recognition. I can generate face image, but I don't know how to insert face image into the correct position of these template videos.
I would suggest you to follow the below 3 steps
Load the template video by opencv, you can access the video frame by frame
Modify each frame, one by one.
Save frame to video stream writer
Regarding step 2, actually, you must copy the uploaded image to the each frame by a mask (the pixel from source image would be copied to destination image if its coordinate on the mask is non-black). The mask could be defined by a list of points OR by an image. You should pre-define a mask for each frame in a file. Then load the mask for each frame and copy.
How to read video, save video OpenCV read-write Video
How to insert image to another image Copy non rectangular ROI
Generating videos like them are all not easy tasks. I recommend to use Adobe After Effects or other video creating software (with some scripts and actions) if you don't need to generate it by a single program or program language.
Then, I answer them below when you need to generate it by programatically.
For the first one, you should recognize faces and bones. So you should use OpenCV. ( I recommend to use tools like OpenFrameworks or TouchDesigner and so on. )
For the second one, I don't know what you exactly want, but if you want to recognize the position of the bottle dynamically, you have to use deep learning or other way to detect it. Then you may need TensorFlow or OpenCV. ( If you just want to merge layers, you can use ffmpeg etc. )
For the last one, you should split the video frame into the boxes, then you have to control. I think there are many ways to implement this. I may use OpenFrameworks, TouchDesigner, vvvv, or Processing.
I think using ffmpeg for them is not recommended. This tool is not the best for generating complicated video. But ffmpeg will do good, for example if you just merge two videos with alpha.
How can I overlay an image onto a video without changing the video file?
I have many videos and I want to be able to open them and overlay a ruler onto them and then measure the distance an individual moved visually. All I want is to play a video and then to open up an image with some transparency and position the image over the video. This way i would be able to look at the video and see how far the individual moved.
I would like to do this without having to embed the image like a watermark, because that is computationally expensive. I would need to copy the video, embed it with the ruler and then watch the video, then delete that video file. This seems unnecessary. I would like to just watch the video and have a transparent image over it while I a watching.
Is there a program that does this all together?
Alternatively, is there a program which I can use to open an image and make it transparent and then move it over the video that is playing?
Note: I am using Windows.
It sounds form your requirements that simply overlaying a separate image layer over the video will meet your needs.
Implementing this approach will depend on the video player client you are using, but you could implement an HTML5 based solution and play the videos locally with this (or even from a URL on the web if you have them there).
There is a nice answer with a working fiddle which shows how to do this with HTML5 here: https://stackoverflow.com/a/31175193/334402
One thing to note - you have not mentioned scale in your question. If you need to measure how far the person has moved in real distance, rather than in just cm's across the video screen, then you will need to somehow work out the scale of the video. This makes things considerably harder as the video may zoom in and out during the sequence you want to measure, so you would need some reference to calculate the scale for each frame. One approach would be to use the individual as a reference, assuming they are in all the frames you are interested in.
What about using good old VLC for that?
Open VLC go to Tools→Effects and Filters→Video Effects→Overlay and select Add logo checkbox:
Then, add your transparent overlay image and play any video with VLC. The output looks like this:
I have been looking for a way to convert a sequence of PNGs to a video. There are ways to do that using the CONCAT function within FFmpeg and using a script.
The problem is that I want to show certain images longer than others. And I need it to be accurate. I can set a duration (in seconds) in the script file. But I need it to be frame-accurate. So far I have not been successful.
This is what I want to make:
Quicktime video with transparancy (Prores4444 or other codec that supports transparancy + alpha channel)
25fps
This is what I have: [ TimecodeIn - TimecodeOut in destination video ]
img001.png [0:00:05:10 - 0:00:07:24]
img002.png [0:00:09:02 - 0:00:12:11]
img003.png [0:00:15:00 - 0:00:17:20]
...
img120.png [0:17:03:11 - 0:17:07:01]
Of course this is not the format of the script file. Just an idea about what kind of data I am dealing with. The PNG-imagefiles are subtitles I generate elsewhere in my application. I would like to be able to export the subtitles as a transparent movie that I can easily import in my video editing software.
I also have been thinking of using blank transparent images I will use as spacers, between the actual subtitle images.
After looking around I think this might help:
On the FFMPEG site they explain about making a timed slideshow
In the Concat demuxer section they talk about making a slideshow, based on a text file, with references to the image files and the duration of the image.
So, I create all the PNG images I need. These images have the subtitle text. Each image holds one subtitle page.
For the moments I want to hide the subtitle, I use a blank PNG.
I generate a text file as explained on the FFMPEG website.
This text file will reference to all the PNGs. For the duration I just calculate the outcue - incue. Easy... I think...