# Wanting to know if VideoIO supports Alpha channels

**URL:** <https://discourse.julialang.org/t/wanting-to-know-if-videoio-supports-alpha-channels/101069>\
**Category:** General Usage\
**Tags:** videoio\
**Created:** [July 2, 2023, 6:30am UTC](https://discourse.julialang.org/t/wanting-to-know-if-videoio-supports-alpha-channels/101069 "2023-07-02T06:30:49Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![HarmonDavid](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/harmondavid/32/51166_2.png) [@HarmonDavid](https://discourse.julialang.org/u/HarmonDavid)\
**Post date:** [July 2, 2023, 6:30am UTC](https://discourse.julialang.org/t/wanting-to-know-if-videoio-supports-alpha-channels/101069/1 "2023-07-02T06:30:49Z")

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Like the title says, I am trying to find out if VideoIO can handle dealing with pixel data that uses the alpha channel.

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**Author:** ![contradict](https://avatars.discourse-cdn.com/v4/letter/c/ac91a4/32.png) [@contradict](https://discourse.julialang.org/u/contradict)\
**Post date:** [July 3, 2023, 8:50pm UTC](https://discourse.julialang.org/t/wanting-to-know-if-videoio-supports-alpha-channels/101069/2 "2023-07-03T20:50:31Z")

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It does not, the list of supported pixel formats for video writing is [here](https://github.com/JuliaIO/VideoIO.jl/blob/master/src/avframe_transfer.jl#L1). I don’t think many codecs support an alpha channel, maybe VP9? I would try to get a pipeline going with the ffmpeg cli and then write to that on stdin. [FFMPEG\_jll](https://github.com/JuliaIO/VideoIO.jl/blob/master/src/avframe_transfer.jl#L1) makes it simple to find and install a copy of FFMPEG for your program to use.

Edit:  
An interesting post about Alpha with FFMPEG:

> **[Alpha Masking with FFMPEG](https://curiosalon.github.io/blog/ffmpeg-alpha-masking/)**
>
> Before I dive into the topic of alpha channel masking in ffmpeg, I should explain what this document is. I’m writing it as a blog post however, I want it to document what I know about how alpha masking is accomplished in FFMPEG.