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0
votes
1answer
30 views

Using ffmpeg to create a video from a sequence of TGA images, with a depth of field blur effect sourced from the TGA's alpha channel

I'm working on turning a sequence of TGA images into a video using ffmpeg. I want the video to have a depth of field blur effect. The alpha channel of each TGA contains a depth-mask, where ...
0
votes
1answer
84 views

Is it possible to overlay video with alpha channel over the desktop in real time (Windows)?

I'm going to run a pen&paper RPG game and one of my players will participate via Skype. I have this idea, to make his appearance more immersive, to cast some sort of futuristic HUD over the video ...
0
votes
1answer
31 views

How do I discard transparency channel when encoding files with bpgenc?

Sometimes png pictures contain redundant alpha channel. While this is usually not an issue, for libbpg it triggers more complicated mode which is not compatible with fast x265 encoding or with ...
2
votes
1answer
2k views

How do I add a background to a transparent png in gimp?

I have a png file with a transparent background. I would like to add a non-transparent background from a jpg. I have tried: Open the transparent png file. I see the picture with the checkerboard ...
4
votes
1answer
874 views

ffmpeg: change alpha channel of a showwaves filter

I've been trying to figure this issue out for a few hours and I can't seem to find any solution. I'm creating a video from an .mp3 and some images with the following command fmpeg.exe -y -i ...
3
votes
1answer
650 views

overlay a sample video with alpha channel over another video in gstreamer

I want to play 2 video files using a GStreamer pipeline on my screen. The first video is without an embedded alpha channel and I want the second video with an embedded alpha channel to be overlaid ...
1
vote
0answers
481 views

opensource vp6a encoding

I am looking for a way to encode a movie with vp6a. I was hoping I would be able to do this with ffmpeg using this command: ffmpeg -i test.flv -loop 1 -i bg.tga -vcodec vp6a -vframes 1037 -b:v 1024k ...
1
vote
1answer
2k views

How do i convert a transparent .mov-file to an mp4 file overlayed on a background-image using FFMPEG

I'm trying to convert a mov file with the following specs: Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'test.mov': Metadata: major_brand : qt minor_version : 537199360 ...
18
votes
1answer
4k views

get pixel alpha value

Given a pixel in an image imported from a png file, how can I get the alpha value of the pixel with the GIMP? If this is not possible, what software can I use to achieve this (OS: Linux)?
1
vote
1answer
333 views

How to combine multiple similar images with “holes” into one good one?

Suppose you have multiple photos of the same object (from slightly different angles), each have some obstacles in foreground. You added an alpha channel to each picture and "erased" the obstacle ...
1
vote
0answers
721 views

.MOV video compressed with PNG has no alpha channel

I have a QuickTime file .mov with alpha channel compressed with PNG codec. What I need is to create smaller version of this file using ffmpeg. Everything works except new mov has no alpha (Adobe After ...
1
vote
0answers
244 views

Render Video as png with Alpha

I have pixel art that I want to put in an animated png. I animated it in the timeline, but when I rendered it into a series of pngs, It has no partial transparency. Anyone know how to solve this?
2
votes
1answer
807 views

Keep alpha transparency in indexed PNG from Fireworks when batch resizing using convert (ImageMagick)

I have a special case where I'm using alpha transparency in indexed PNGs from Fireworks to keep the file size of PNG's in an iOS game down. (That is, indexed colors like an 8bit PNG but alpha ...
0
votes
2answers
73 views

How can I convert the color in this button into an alpha transparency so that any background will show through, changing the color of the button?

The button has a layer in it that has a bevel/emboss filter on it. I'm stumped. Here's the PSD that I'm trying to convert.
4
votes
6answers
4k views

Is there any way to save a PNG-8 file with Alpha Transparency in Photoshop?

I recently discovered something that I previous thought was impossible: PNG-8 files can store Alpha Transparency in the same way as PNG-32 files can. Not Indexed Transparency (like GIFs), but full on ...
0
votes
1answer
2k views

Convert TIFF with Alpha Channel to PNG?

I have a TIFF File that has a blue background and an Alpha Channel. I would like to save a PNG File which has the blue background transparent, using the Alpha Channel (because some pixels are not ...
8
votes
8answers
15k views

Extracting the layer transparency into an editable layer mask in Photoshop

Is there any simple way to extract the "baked in" transparency in a layer and turn it into a layer mask in Photoshop? To take a simple example: Let's say that I paint a few strokes with a ...
2
votes
1answer
783 views

Alpha plugin in GStreamer not working

I'm trying to compose two videos, and I'm using the alpha plug-in to make the white color transparent. To test the alpha plug-in I'm creating the pipeline with gst-launch. The first test I done was: ...
6
votes
2answers
4k views

Point sample opacity/alpha in Adobe Photoshop?

I opened a PNG containing an alpha channel in Photoshop and wanted to get the opacity / alpha of a given point in the PNG file, so that I could match that opacity in a new photoshop layer. How can I ...