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Alpha Channel Video


jkb

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I have read the post on Alpha Channel with Lagarith Codec & installed PTE 11.02 build 2 but I still cannot get an alpha channel video to display without showing a black background instead of transoarent.

If I import the video into Photoshop it displays with a transparent background.
How do I tell PTE to display as Alpha Channel??

I have tried creating the video as a straight Alpha & also as RGB+pre multiplied Alpha & still can't get it to work.

It is in ProRes format as a .mov file

Importing into Photoshop & then exporting as a .avi file greatly reduces the file size from 890 mb down to just over 7 mb, but PTE is still not displaying the transparency.
The only way I can get it to work is to reduce the opacity to enable the image underneath to show through but this darkens the image as the black background of the video is still partly visible.

Any help would be appreciated.

Jill

 

PS Some videos I need to keep as RGB+pre multiplied Alpha to keep the individuals colours within them.
Others are fine as straight Alpha as I can easily colour them as one colour within PTE

 

 

 

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Hi Jill,

For Windows I think you would either have to install the lagarith codec or install virtualdub2. I did my testing with virtualdub2.

https://lags.leetcode.net/codec.html

http://virtualdub2.com/

Tom

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6 hours ago, Igor said:

Alpha channel (Lagarith Codec and others)

Hi Igor,

I have installed 11.0.3 but still cannot get my videos to show with a transparent background.

I have sent you sample videos & project by WeTransfer.

Jill

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11 hours ago, jkb said:

I have installed 11.0.3 but still cannot get my videos to show with a transparent background.

I have sent you sample videos & project by WeTransfer.

Jill,

Try a new Beta version:

https://files.wnsoft.com/test/pteavstudio-setup.exe

11.0.2 Build 3

It should display correctly Alpha channel for 2 videos which you've sent me.

And 3rd video (LightWisps01.mov) doesn't include Alpha channel).

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39 minutes ago, Igor said:

It should display correctly Alpha channel

Igor, thank you for fixing this so quickly.

It works great for the RGB+Premultiplied Alpha.
The other video which I think is Straight Alpha doesn't show up that well, but that could be the video itself.

 

If possible it may be useful if we could have a Checkbox for Video to set Alpha Channel On or Off as we have for Still images?

Jill

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Jill,

Glad that the first video now works fine.

When you export a video with Alpha, please don't choose "Premultiplied" option. Probably it will help to reach desired visual result.

I noticed that first 2 videos are in ProRes format which is heavy for realtime playback. And Alpha channel is 12-bit. It seems that this format is intended for professional use. File is also very large.

Try to choose H.264 format with Alpha channel. If it will not be recognized in PTE, we'll add its support.

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52 minutes ago, jkb said:

If possible it may be useful if we could have a Checkbox for Video to set Alpha Channel On or Off as we have for Still images?

I'm not sure that it requires one more option. Probably it's very rare case? There is alternative solution - put a black rectangle below a video clip with Alpha channel.

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19 minutes ago, Igor said:

Try to choose H.264 format with Alpha channel.

Thanks I will give this a try later.

 

14 minutes ago, Igor said:

put a black rectangle below a video clip with Alpha channel.

Thanks for the suggestion

 

Jill

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You are right VLC does not play it, on the other hand Windows media player, Potplayer and QuickTime do play them well.

And video editors like Adobe premiere, Magix vegas or AE also support it, I think it's open source.

It would be good for its level of compression and quality, but if you can't, there's not much more to say

Thank you so much.

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On 2/22/2023 at 2:33 PM, Igor said:

Try to choose H.264 format with Alpha channel. If it will not be recognized in PTE, we'll add its support.

Hi Igor,

I have tried H264 output & it is not recognised in PTE.

I have sent you some sample files & details of how they were created, see email.

Jill

 

 

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1 minute ago, jkb said:

Hi Igor,

I have tried H264 output & it is not recognised in PTE.

I have sent you some sample files & details of how they were created, see email.

Jill

 

 

I don't know of any software that can create H.264 alpha channel. Newer Apple Macs can use H.265 alpha channel videos, but not Windows.

My idea was for PTE to add alpha channel support for the webm VP8/VP9 codec. PTE on both Windows and Macs can already play webm video files. The encoding time is slow but the file sizes are small.

I would like to try H.264 alpha if you know how to make them.

Tom

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1 hour ago, tom95521 said:

I would like to try H.264 alpha if you know how to make them.

H.264 does not support alpha channel, the only solution is to create the alpha channel separately, to be able to use it in PTE, after trying different codecs that support alpha channel, you find that the ones with the least weight are not supported by PTE and the others have a considerable weight.

I am going to continue creating files in .mp4 (h.264) and the other video only the alpha channel, between the two videos the size is less than any file created with embedded alpha channel, at least until I know of an option better.

 

Example: https://we.tl/t-Kxwnfvv7bf

 

 

okm1e-Tuqm-D.png

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5 minutes ago, jienense said:

H.264 does not support alpha channel, the only solution is to create the alpha channel separately, to be able to use it in PTE, after trying different codecs that support alpha channel, you find that the ones with the least weight are not supported by PTE and the others have a considerable weight.

I think VP9 is as good or better than H.264 in quality and file size and is supported in PTE on Windows and Mac?

Tom

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Hi Jienense,

Currently PTE can play webm video files, but it can not decode the alpha channel in the webm files. Yes, software encoding to VP8 or VP9 is slower than H.264 hardware encoding. If you have an alpha channel video that Shutter Encoder can read then it can convert to webm with alpha channel.

Thanks,
Tom

ShutterEncoder.png

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