Tutorial: How to export a video with transparency

Ingenious, and it gives a real classy effect. Brilliant, and thanks for the mini-tutorial!

I do too, but mine doesn’t come out as crisp …

These are my Screen recording settings. I have Record using lossless encoding checked because I figure that maybe if ShareX doesn’t have to compress while it’s recording, the end result will be smoother. Maybe it does something to the quality of the video too… who knows :slight_smile:

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Thanks, I’ll try those settings.

I observed the use of GDI as a capture device in ShareX.
Then I read about the difference between GDI and Screen-capture-recorder here:
Difference between “gdi grab” and “screen-capture-recorder” · Issue #4692 · ShareX/ShareX · GitHub

GDI grab - Records the screen with built-in FFmpeg methods.

screen-capture-recorder - Records the screen using the open source DirectShow filter.

Lossless capture I suppose will avoid latency (I don’t know) but subsequent conversion will introduce a loss of quality (visual or not) depending on the CRF quality setting.

I guess @jonray’s question is also related to the sharpness of your video in the enlargements of a part of the Shotcut interface.

I am still experimenting with some things about this.
In my short videos about audio filters, I replicated the filter interface in Inkscape in my first video.
In the second video, I used an image scaler (Waifu 2x).
If the capture quality allows such a scaling, I would not need intermediate steps to show the interface of each filter clearly.
This implies that I did some things in W10 (ShareX and Waifu2X) and Shotcut editing in Ubuntu Studio.
I will review the settings of my screen recorders in Ubuntu Studio (VokoScreen and OBS Studio) to improve the detail for the enlargements.

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Thanks @ejmillan, I will look into the GDI grab, and also Waifu 2x looks interesting. Thanks!

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In my ShareX settings, I have the choice between GDI grab and none as a Video source.

Here are some results I get using SP&R to zoom a screen capture

100%

120%

150%

200%

300%

There is an option to install other options.

Here are some interesting results with an external scaler
Original


X2

x3

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What is the advantage of installing the screen-capture-recorder in ShareX?
I’ve read the forum thread you linked, but honestly, I didn’t get much from it.

Your examples look very nice when seen as previews. But at full scale as we would see them when used in a video project, we can see the heavy work done by the scaler. Particularly on the text.

Your 3x example seen at it’s full size of 2157x1392
scale3xExtRescaler

It’s not unpleasant. But how complicated is it to use an external scaler ? Do you import a video in it, and export it again after it rescaled the video, then import the result in Shotcut? If so, it may be faster (but maybe not as efficient) to just add a Sharpen filter in Shotcut.

Here’s the video with SP&R at 300% and before & after using the Sharpen filter:

I know this option because I needed audio recording as well. So I installed both options. I didn’t test the advantages or disadvantages of each of these options so I can’t say which one is better for me.
I used to record with OBS, but in some circumstances recording with ShareX worked better and in other cases OBS was better.

With the scaling issue I didn’t use the highest quality or processing for this sample graphic, but I will concede that SP&R + Sharpen does a very decent job.
The advantage? It just depends on your needs, nothing more.

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I always have the Audio Source set to none, because I rarely need to capture audio. But I know I can record Audio with ShareX without installing virtual-audio-capturer.
I just choose one of the choices ShareX gives me:

But I’ll try installing the recording devices. I’ll compare with my actual settings and get back to you with the results.
Thanks !

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Thank you @ejmillan and @MusicalBox for your observations. I will look into this tomorrow when I can grab a moment. Very interesting stuff!

OMG , the sharpen filter!! Why didn’t I think of that!!! Doh, will experiment with that tomorrow. @MusicalBox, did you use the sharpen filter on yours, and if so, what were your settings? Thanks!

Hi @jonray. I didn’t use the Sharpen filter in the tutorial. Didn’t think of it at the moment.
I don’t remember exactly what settings I use for the captures I posted above, but I always keep the size low, between 10% and 15%, then I play with the amount. I think it was around 60%, but I’m not sure.

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This thread is straying from its original topic, sorry.
Either way, it’s interesting stuff.
I looked into this particular issue and found that W10 does not enable “Stereo Mix” as a recording device by default. That’s why I didn’t have any audio input device in ShareX.
So I just had to enable this in the W10 audio settings.
This does not seem to affect OBS Studio, as it can capture audio from the desktop without enabling Stereo Mixing. I guess the extra step I needed in ShareX, is not needed in OBS and it already installs what is needed by default.

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Don’t worry about going off topic @ejmillan. Like you say it’s interesting stuff. Anybody brave enough to read all the 64 posts in the thread will probably learn something they don’t know about Shotcut. And I’m happy about that.

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All of a sudden, I’m getting a lot of questions about the resulting file saying “invalid.” Did the newer version of Shotcut lose something that no longer allows this?

I tried to replicate it myself and this is what I got on both VLC and Shotcut…

image

Yes, this is said to be fixed in the next release. You can read about this in this post:

Got it!

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I’ve just tried this with a project that I’m doing. When bringing the exported transparent video into another project (the .mov), the exported video is transparent. However whilst the “background” (the chroma keyed background) works as intended, I have, within the original exported project an image that is 60% translucent. That image’s translucence is lost when brought into the new project.

So the 60% translucence of the image is lost when exported and brought into the new project. However in the project (not the new one but the .mov export) If I add a video below the the 60% translucent image, I can see that the video “passes through” the 60% translucent images on the tracks above.

So the workaround would be to just add the main video on the lowest video track and export but the .mov contains 12 video tracks (excluding the main video) and my machine takes an age to export just a few seconds of the .mov.

So, has anyone got any potential ideas to export the transparent mov whilst also retaining partial transparency of the images within the .mov when exported?

I’m thinking this is just the nature/limitation of exporting /chroma/transparency/partial transparency and I’m not going to achieve what I want.

Any feedback appreciated.