Questions tagged [alpha-channel]
The alpha-channel tag has no usage guidance.
35
questions
0
votes
1
answer
90
views
ARGB in Adobe Illustrator
I need to create some icons and my client's requirements are (A: 0, R:255, G: 255, B: 255) for the background.
I'm working on Adobe Illustrator, how do I change the Alpha?
When the background is ...
- 1
0
votes
1
answer
6k
views
Transparent Video (RGB+Alpha) in PowerPoint
I am able to export a transparent-background video in After Effects - AVI with RGB+Alpha. It was of a man talking with a green screen background.
However, once I import it to PowerPoint, a black ...
- 125
1
vote
0
answers
500
views
ffmpeg stuck on last couple of frames during alphamerge
I'm trying to put alpha channel on an mp4 file, using an alpha file that I have previously extracted. The command that I'm using with some tuning flags is this:
ffmpeg -hide_banner -i video.mp4 -i ...
- 11
0
votes
1
answer
2k
views
ffmpeg merge videos including one with alpha transparency with mp3 audio
I have two video tracks (one with alpha transparency and both without audio) and an audio file, I need to put them all together with the same beginning.
so:
I only managed to mix the two videos ...
- 51
2
votes
1
answer
640
views
Is it possible to compress alpha and RGB channels of PNG sequence separately with FFmpeg?
Suppose I have a sequence of 32-bit (RGBa) PNG files. Is it possible to compress the RGB channel with one codec and the alpha channel with another? For example, if I had the RGB and alpha as separate ...
- 1,630
3
votes
1
answer
5k
views
Lossless VP9 Webm Encoding of PNG Sequence with Alpha in FFmpeg
I'm trying to encode a sequence of 32-bit 8bpc PNG images (RGB with an alpha channel) using the lossless VP9 codec with ffmpeg; specifically:
ffmpeg -framerate 60 -i out%04d.png -c:v libvpx-vp9 -...
- 1,630
3
votes
1
answer
6k
views
Lossless Video Codec supporting Alpha Channels
Suppose I have a sequence of PNG image files which may or may not contain an alpha channel (assume those that do have an alpha channel actually utilize it). While PNG files themselves have their own ...
- 1,630
0
votes
1
answer
826
views
Alphamerge filter only works on first frame
I am trying to implement blur filter over specific non rectangle object, I have mask and sample video but the issue is that alphamerge result of first frame of video is applied to the whole video(Like ...
- 97
0
votes
1
answer
472
views
Convert bmp to png and black colors to alpha
I exported some sprites from the game Half-Life; however, they seem to have tones of black instead of the alpha channel. For example:
How do I convert the black colors into alpha/transparency?
2
votes
1
answer
188
views
Integrating ffmpeg4 with Pyglet. What is correct method to identify streams with alpha?
We're trying to interate ffmpeg4 with Pyglet.
Its all going very well but we have one issue:
If a VP9 (or VP8) file is created using ffmpeg4, from png files with alphas, we get a video file (webm) ...
- 121
0
votes
1
answer
471
views
How to get exact alpha value in Photoshop
I need to know the exact alpha value of a pixel in Photoshop. I tried using the answer in this question (Determine pixel alpha value in photoshop), but that gives me an opacity percentage such as 27%, ...
user169819
0
votes
0
answers
133
views
Apply depth of field blur effect from a grayscale video using ffmpeg [duplicate]
I have two videos.
One is a normal video, the other is a grayscale video.
Supposedly, merging the videos I can have a video with a depth of field blur effect.
I wish to know how I could do it using ...
0
votes
0
answers
184
views
How to concatenate different sized videos and then overlay with transparency on a background in ffmpeg?
I have multiple videos that are different sized, and I needed to concatenate them and then put the finished concatenated result on top of a 1080p background. However, the only way I can currently do ...
- 11
12
votes
3
answers
18k
views
Turn grayscale into alpha channel in Paint.net
I have a PNG image that has many shades of gray and no transparency:
I would like to turn the grayscale into an alpha channel in Paint.net, so that the parts that are completely white would become ...
- 2,589
2
votes
3
answers
14k
views
ffmpeg -- How do I overlay a PNG over another PNG?
I have PNG A with alpha layer, which I want to overlay on top of another PNG B. How do I do that with ffmpeg?
I tried ffmpeg -i A.png -i B -filter_complex "[0:v][1:v] overlay=0:0" out.png, but I ...
- 123