i have series of pngs with transparent background
when i'm trying to create gif using
ffmpeg -framerate 24 -i img%03d.png z.gif
my tranparency turns into black mess
what should i do to avoid this?
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I have some videos of resolution 1280 X 720 with black padding area in both left and right side around the display area of all videos. I want to display a static image in padding area of video instead of solid black color. I am working with FFMPEG library but can't find any way to do so. Can you please help me regarding this?
Thank You!
Use the cropdetect filter to determine crop parameters to remove the black. See Remove black bars using ffmpeg for an example of how to get the crop parameters.
Crop the black area and overlay the video over the image:
ffmpeg -i video.mp4 -i background.jpg -filter_complex "[0]crop=404:720:438:0[vid];[1][vid]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2" -c:a copy output.mp4
Well, after trying some commands I made a command to do so and its working for me.
ffmpeg -loop 1 -i image.jpg -i video.mp4 -filter_complex "[1:v]scale=1280:720:force_original_aspect_ratio=decrease:-1[fg];[0:v][fg]overlay=(W-w)/2:(H-h)/2:shortest=1" output.mp4
I have a set of transparent images, where each one represents a frame of a video. I know that I can overlay them on top of another video using -i %d.png. What I want to be able to do is turn them into a transparent video ahead of time, and then later be able to overlay that transparent video onto another video. I've tried just doing -i %d.png trans.mov and then overlaying trans.mov on top of another video, but it doesn't seem like trans.mov is actually transparent.
You have to use an encoder that supports transparency/alpha channel. You can view a list of encoders with ffmpeg -h encoders and get further details with ffmpeg -h encoder=<encoder name>, such as ffmpeg -h encoder=qtrle. Then refer to the Supported pixel formats line: if has as "a" in the supported pixel format name, such as rgba, then it supports alpha. See a general list of pixel formats with ffmpeg -pix_fmts.
The simplest solution is to mux the PNG files into MOV:
ffmpeg -framerate 25 -i %d.png -c copy output.mov
I have a bunch of png images made from a python script. When I convert the images to a mp4 format using ffmpeg, the video looks good. But the moment I make them into gifs it starts creating random yellow patches as shown below.
The syntax I use to convert png to gif is ffmpeg -i img%04d.png animation.gif
Thanks.
I would like to convert png animation file to gif in windows,
I choose to use ffmpeg, as I have many of pngs to covert, cmd is quite straight forward in this case.
the sample img here:
https://i.imgur.com/SPGGMEb.png
tried:
ffmpeg -i SPGGMEb.png -vocdec gif output.gif
everything seems fine but the transparent background turns to black, as:
https://i.stack.imgur.com/7CbO8.gif
how can I keep the transparent background during conversion?
I am generating an animated gif from an mp4 ... but due (I think) to color reduction (gif requires -pix_fmt rgb24) the result is somewhat ... blotchy? like running an image through an oil paint (or maybe "posterize") special effect filter. I think that the quality could be better, but I don't know what to tweak.
Not sure about this ... but ooking at the color palette of the resulting gif in an image editor it does not even appear to have attempted to create a color palette specific to this clip, but instead is attempting to us a generic palette ... which wastes a lot of pixmap space. That is, if I am interpreting this correctly.
Any tips on preserving the original video image instead of getting a "posterized" animated gif?
To get better looking gifs, you can use generated palettes. palettegen filter will generate a png palette to use with the paletteuse filter.
ffmpeg -i input.mkv -vf palettegen palette.png
ffmpeg -i input.mkv -i palette.png -lavfi paletteuse output.gif
You can try using -vf format=rgb8,format=rgb24.