Questions tagged [alpha]

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1answer
33 views

Creating transparent video from transparent png files using ffmpeg

I have a set of 300 transparent png files and I would like to create a transparent video file from them. I'm using the ffmpeg command as follows: ffmpeg -f image2 -i anim.%04d.png -r 30 -vcodec png ...
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1answer
26 views

How to convert a black and white video to a APNG file while setting a color as transparent?

I created a small video with threshold filter to get black and white pixels (no greyscale): ffmpeg -y -i /dev/video0 -f lavfi -i color=0x606060:s=640x480 -f lavfi -i color=black:s=...
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1answer
11 views

Audio not detected with Transparent Video Formats (Quicktime - PNG/QtAnimation- AAC/PCM)

On importing a transparent .mov file (Quicktime - PNG/QtAnimation- AAC/PCM) , the audio is not detected by the Videoeditors (Powerdirector17 < Davinci Resolve doesn't support the above format> )....
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0answers
41 views

KDEnlive: how to use as input a video with transparency? (Goal: compress sequence of png)

I'd like to import in KDEnlive (but I'm also interested by other open source softwares) a video with transparency. The goal is to compress a sequence of png with transparency (produced by Natron) that ...
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0answers
15 views

ffmpg (copy existing settings?) or crop a .mov with alpha and have it be open-able using Quicktime (not VLC)

How do you have ffmpeg copy all existing settings except the crop dimensions of a video file? I've been struggling to crop an .mov with alpha channel (transparent video), so that it can be opened ...
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0answers
27 views

Importing Clip with Alpha Transparency into Resolve

Working on a video for a client with a third party animation company. I need to figure out a file format they can export video with alpha transparency, that Resolve will import correctly. Ordinarily I ...
0
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0answers
45 views

Hevc Transparent Channel? (Apple WWDC19)

So, Up until now, HEVC Supported Transparent. But there wasn't any encoding Software To Encode that Transparent Pixels in it. Until Apple made their Own Way of Putting Alpha pixels inside a consumer ...
1
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0answers
25 views

After Effects doesn’t handle premultiplied images correctly

I’ve been told by various people in the industry that AFX doesn’t handle premultiplied images correctly and I’ve been able to verify this myself in my own pipeline. I’m just not sure if we are all ...
0
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2answers
142 views

How to mask a mp4 video with another alpha mp4 video

A noob question. I have two mp4 video files. The first one is ordinary color video (right side). The second one is transparency mask video (alpha), it's a mp4 video not an image (left side). This ...
0
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1answer
14 views

Does any software have the capability to create a mask/alpha value based on the volume of an audio channel

I'm looking for an automagical way to create a Google Hangouts effect, ie. 1. I have a number of files that are recordings of individual conversation members. 2. I want to put together the video ...
1
vote
1answer
3k views

Mask clip with transparency in DaVinci Resolve

Is it possible to use some combination of Color nodes and power windows to hide parts of an already partially transparent clip such as one whose frames might be made from transparent images like ? I'...
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0answers
150 views

ffmpeg prores alpha channel quantization looks pretty bad

Might be related to this other ticket? I've been doing some prores tests for both color and alpha. Usually this isn't a big deal since my alpha channels are solid with a 1-2pixel transition to black....
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1answer
250 views

ffmpeg prores alpha channel not present when colormatrix and colorspace operations are performed

So I've figured out how to convert images to prores with no colorspace shifts using either: -vf colormatrix=bt601:bt709 filter for 8bit material and -vf colorspace=all=bt709:range=pc:format=...
1
vote
1answer
32k views

Make white background in MP4 movie transparent

I have a short animation clip made with PyMOL software (visualizing molecules), in the MP4 format. I am going to use this animation in future presentations, and it would look much better if the ...
2
votes
1answer
3k views

Create Alpha channel-Videos (obs stinger compatible) with ffmpeg and 2 files

I have 2 video files. One file is the main content and the other file has an alpha channel emulated with black and white (white = opacity 100 and black = opacity 0). Sometimes the emulated alpha ...
2
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0answers
301 views

FFMPEG drops end frames when converting a unmatted alpha .mov to .webm using ffmpeg but converts fine when alpha is premultiplied?

I am using ffmpeg to convert a straight alpha .mov to a webm so I can layer videos on top of one another for a web game however when converted the duration is the right length but the frames freeze ...
0
votes
1answer
681 views

ffmpeg fade to specific color values over time

I have a background image that I'm trying to fade to specific color values using this filter: lutrgb=enable='gte(t,3)':'r=0.3*val:g=0.3*val:b=0.3*val' This almost works, but it changes the values ...
0
votes
1answer
304 views

Using brush tool for alpha channels/rotoscoping in after-effects

I'm trying to rotobrush/rotoscope a bunch of footage, see image below for what I mean. Currently I'm using the rotobrush, but it is too time-consuming and slow - it keeps trying to guess the paths, ...
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1answer
1k views

What is the difference between RGB and RGB + Alpha?

I know what is Alpha channel but when I rendered a motion logo using RGB and RGB + Alpha in After Effects, I didn't see any difference. So what's the basic difference between them and how to decide ...
7
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3answers
16k views

Is it possible to export a Video with transparent Background? (No Image Sequences!)

Is it possible to export a video file from After Effects with transparency? I don't want to export to an image sequence.
1
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0answers
70 views

export a video from Blender with alpha channel

I have a problem exporting a video from Blender (Cycles Render) with Alpha Channel. Generally it's a scene with sailplane flying about a camera positioned near to the floor. In addition to this it is ...
2
votes
1answer
106 views

Is it possible to mask out unsharp areas of footage with After Effects?

Is there any existing filter/effect, that will automatically mask out the unsharp area of my footage? Let's say I have an object in focus and a lot of depth of field. How do I show only my sharp ...
2
votes
1answer
647 views

Maya batch render missing alpha channel

I'm trying to export a scene to composite in Nuke. When I "render current frame" and save the image from there, I get an image with an alpha channel, but when I batch render the images don't have the ...