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Png-24

Hi

(My first post here: gotta say, I like vvvv a lot. Superb software. Thanks to all the developers.)

Question:
Does “Writer (EX9.Texture NRT)” support PNG-24?

(In other words, is it possible to save a PNG sequence with a transparency layer / alpha channel ? – If just prior to saving the files, a background subtract is performed, then PNG-24 would have tranparent regions; normal PNGs do not. )

Many thanks,
Jhave

sory. no. the writer is using microsoft-directx routines to save files. and those don’t seem to support alpha for .pngs

correcting myself…see below

the only way to save alphachannels is to use the .dds format. use a plugin to open in gimp or photoshop…

Hi

(My first post here: gotta say, I like vvvv a lot. Superb software. Thanks to all the developers.)

Question:
Does “Writer (EX9.Texture NRT)” support PNG-24?

(In other words, is it possible to save a PNG sequence with a transparency layer / alpha channel ? – If just prior to saving the files, a background subtract is performed, then PNG-24 would have tranparent regions; normal PNGs do not. )

Many thanks,
Jhave

I think I’ve done alpha’s with bmp, just make sure you set the dxtexture channels to rgba

Thanks for all the swift replies…
I was sorry to hear that PNG-24 is not supported by DirectX routines…

.dds will probably not work for my purposes since i intend to feed images directly into flash unless there is an automated batch processor in realtime that doesn’t suction too much cpu

and i tried modifying the Renderer Windowed Backbuffer format and outptting BMP but alpha channel is not saved…
…i am a total newbie but it seems impossible to go from DXTexture to that WriterEX9Texture so i tried as many of the Renderer ARGB settings as I could without any success…

i started out trying the AVI writer
I assumed alpha channel transparency was not possible with AVI
(i did some outputs with various settings)
pls correct me if i am wrong…

thnks again

uh…

i thought i’ve tried this before, but i just made a quick test and noticed that as cat mentioned .bmp indeed saves with 32bit including an alpha channel and so does .png.

make sure your dx9texture which you can connect to Writer (EX9.Texture) uses a format including an alpha channel: open an inspektor (Ctrl+I) and select DX9Texture (EX9.Texture). there you’ll see the format pin which you set to A8R8G8B8.

also note: when you want to connect Writer (EX9.Texture) to the output of a Renderer (EX9) you need a DX9Texture node in between. the Writer (EX9.Texture NRT) module has that node included. rightclick the module to open it and see.

and right. avi with alpha is not possible.

Again thanks for the correction

…following your advice I found the DX9Texture node associated with Writer (EX9.Texture NRT) and set it to A8R8G8B8

but the resulting images do not have any transparent regions in them…

my problem could really be in several places:

the BackgroundSuppression: does it remove the background? or does it replace it with black?

Renderer node Background Color is HSV and A which I assume stands for Alpha 1.0 …is there a way to set this value to 0.0? Is that necessary?

BMP is saving as XRGB…since i pulled one into photoshop and did a manual colour pick, but it didn’t permit me to save out image as ARGB

all help appreciated…

i attach a file just in case my error is newbie obvious…

BackgroundSuppression w Writer ex9.v4p (17.7 kB)

ya. i guess your problem is with the BackgroundSuppression effect. its output is fully opaque, ie. it doesn’t contain any alpha values other than=1.

the renderer nodes background color does not matter. what ever color that is, when you save the thing to a file the renderers background will be transparent. ie. there where no specific objects are rendered will be transparency.

when you set the DX9Texture to ARGB instead of RGB or XRGB .bmps and .pngs should save as 32bit. i tested that with the free image viewer: www.xnview.org. when loading the files you see 32bit mentioned in the status bar and pressing “m” (for mask) lets you toggle betweeen the alpha channel and the image.