Deformed particle effect
Used HF to create a particle effect Shooting Star, a small 1s video with transparent background to be launched as overlay in realtime within a DJ/VJ sw I will use this weekend in an event (not the more advanced use of HF, I know).
Using chroma key I did remove the black background and generated the uncompressed AVI file.
Problem is the falling star appear to be nice inside HF, but deformed inside the video file, next two screenshot
Shooting star inside the final video
I wanted to play with chroma key settings but none make any difference inside HF preview, so difficult to say what is wrong.
Comments
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That's an alpha channel issue. The transparency around the edges is created by the alpha channel, but in order to create the fade, the alpha needs solid color underneath to wok with. You are seeing the color data, without the alpha channel applied. so, you need to change the way the alpha is displayed, I think Premultiplied is what you want, but I might be remembering that wrong. If I am, try the alpha options until you find the one that looks right.
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Discovered I can replay the effect in HF setting the color mode in RGB Straight in the preview window.
This is the MediaInfo of the HF generated AVI (uncompressed, non interlaced, RGBA settings): there is anything I need to change in the export setup? Didn't find any Premultiplied parameter in HF.
General
Complete name : C:\Miei\Geniya\Scuola\Saggio 2015\Video\Test effetto\Effetto 2.avi
Format : AVI
Format/Info : Audio Video Interleave
File size : 206 MiB
Duration : 1s 40ms
Overall bit rate : 1 659 Mbps
Video
ID : 0
Format : RGBA
Codec ID : 0x00000000
Codec ID/Info : Basic Windows bitmap format. 1, 4 and 8 bpp versions are palettised. 16, 24 and 32bpp contain raw RGB samples
Duration : 1s 40ms
Bit rate : 1 659 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 25.000 fps
Bit depth : 8 bits
Bits/(Pixel*Frame) : 32.000
Stream size : 206 MiB (100%) -
Sorry I was unclear, its not something you need to change in HitFilm, you need to change it in the application you are using to play back the exported file. In the images you attached, that would appear to be Quicktime, IN which case you would open the Properties for the clip, select the video track, then open visual Settings and use the Transparency menu to try the different options.
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Mmmm I need in fact to use this small video inside an app named Cross DJ, not sure is possible here to change anything about how alpha channel is used.
There are anything I can change in HF production process to be sure the file is reproduced correctly?
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Problem here is that the user manual for Cross DJ as available from the manufacturer doesn't talk about it's video capabilities... At all. So, I can't determine what settings Clean DJ might have to deal with alpha channels. You can try exporting your video as a PNG sequence, or add a black plane underneath your star and see if Clean DJ can overlay that in a screen or add mode, but, since the Clean DJ manual has zero information on it's video features, there's nothing I can do to guarantee anything will work for you.
It really depends on Cross DJ's software. Hitfilm seems to be functioning correctly.
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Nothing to say over HF, simply I didn't find a way to display correctly the video outside HF.
Using QuickTime, VLC, Windows Media Player I did always obtain the same result, nor did find any way to customize the alpha channel usage. Maybe in QT Pro? I did have the standard version.
About Cross DJ I will care with it after finding a way to play it correctly on more standard players such above.
