Look at this code i've written so far to capture video/audio from camera with directshow:
https://gist.github.com/LinArcX/b43ce8b1905b165de2314e6f9b202c8c
It works but it uses MEDIASUBTYPE_RGB24 and the result is colorful. I want to remove colors and have a grayscale video as output. Someone said that i can use YUV subtype and remove UV from it. But i don't have any idea how do that in my code.
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Turns out I’m working with the Autodesk Forge viewer and Three.js, trying to render 2D text that can be interacted with (specifically select, rotate, and move).
To do this I am working with meshes (using MeshBasicMaterial, Mesh and TextGeometry) but it turns out that the text does not look perfectly sharp, it presents aliasing and I found that according to the API reference, the antialiasing is not applicable to 2d.
Here are some examples of the problem, as you can see, the more I move away from the plane, the worse the text looks (and even up close it doesn't look perfect):
I have tried to make a test representing the text with a Sprite (despite the fact that it would mean having to change the entire implementation already made with meshes of other functionalities) but apart from the fact that I cannot see it, I have seen example images and they do not appear either well: aliasing is visible from a distance and it looks really blurry up close. Here some examples:
Is there a way to correct this problem or is this the most I can get in 2D? I've tried searching for information on this but can't find anything helpful. And what has puzzled me the most has been realizing that antialiasing was not applicable in the case of 2d, like making it clear that nothing can be done to fix it.
I would be very grateful if you could solve my doubts, thank you very much in advance for your help.
An easier alternative, is to just use a higher pixel ratio for the renderer...
window.devicePixelRatio=2;
viewer.resize();
For example, using the custom geometry text, from Joao's demo, you can see the same aliasing issue at DPR=0.5 and DPR=1.0 ...
https://joaomartins-forge.github.io/textgeometry-sample/
But when I set the DPR=2.0, the text looks clean. The trade off is rendering performance, but your 2D drawings may be simple enough that it won't matter. You can use a 'mouse up' camera settle trick, to switch between DPR of 1 and 2, if you want a better UX experience.
There are a few ways to solve this aliasing issue for 2D (and 3D text).
The way I would recommend for your use case, is to use DIV elements (THREE.CSS3DRenderer), instead of text converted into three.js tessellated triangle geometry, as shown in this blog post:
https://forge.autodesk.com/blog/how-do-you-add-labels-forge-viewer
You can find out more information about THREE.CSS3DRenderer here:
https://threejs.org/docs/#examples/en/renderers/CSS3DRenderer
and an Example here: https://threejs.org/examples/#css3d_periodictable
Using CSS3DRenderer instead of CSS2DRenderer, means you will get the correct scaling (and rotation) of the div element as you zoom into your 2D drawing and the mathematics inside the calculation for the matrix transform has less edge-cases.
Once you are using DIV elements for your text, you will notice that the text is sharper and has no aliasing issues. That's because it is not being rasterized by the webGL pipeline, but by the SKIA library used by chrome/firefox/opera/etc for rasterizing text.
There is one final option, that uses signed-distance fields, but it's probably overkill for what you need.
Let me know if you want some example code.
Is it possible to animate text/object with 'end' in after effects just like you do with strokes? How can I achieve this? See the video and you'll understand what I wan't to achieve.
YouTube - Guy showing the 'end' on a stroke
Cheers,
Tommie
I think I see what you are asking. You want the shapes of a text layer (the actual lines of each character) to actually build on, right? Can't be done like that. Even if you use text and convert to shapes, you are looking at a world of pain because of the way letters are built by most fonts (for one thing, the shapes are actually filled, not stroked -- strokes are outlines).
The only way I would do this is by using the Element 3D plugin in After Effects and Cheetah3D (or whatever 3D tool you want to use). In Cheetah, I'd create the text shapes as extruded 3D text. Then I'd use the "Build" modifier ("Linear" setting) to progressively build the text. Then I'd export that out as an OBJ sequence (script for this is available on cheetah forum site -- I wrote it) and bring that sequence into Element3D and work with it that way. That will work. And as far as I know, that's the only way with a decent amount of control. Wedding video? Just curious. :-)
A video player can interpret a file(mp4,avi...)to picture on screen.
Qt can draw lines,rectangles,pixmap...to picture on screen.
What is the difference between them?
You're comparing apples to oranges. They are completely different.
A video player reads a video stream from a file and decodes it using a decoder (DivX, XviD, x.264, etc.), displaying the output on your screen.
Qt4's object painting allows you to paint pixels onto a QObject. That's basically it.
Video decoders are heavily optimized and some even use GPU acceleration. Qt4's object painting isn't made for rapidly-changing frames and is used do draw basic things.
We are desperate to convert an image so that it can be used as an image map. Everything I have tried, really doesnt cut the mustard. I havent the experience to work at very high resolutions.. plus I dont know the terminology and neither have the skills or resources to invest in learning how to do this, knowing many others on here and the internet have far greater experience.
I have downloaded and played with Inkscape, but really am going round in circles...
So thought I would ask here.
What I am after is similar to Raphael Australia Map or David Lynchs, http://davidlynch.org/js/maphilight/docs/demo_usa.html
No frills, no effects, just change the state color of the map on hover and retain that event on click.
Here is what we have ...
What we have is a MAP like this.
We lost the original file, which was pure gray. I have this left :(
Anyway, we want it so that each state ( including the territory ACT ) not indicated on the above map, represented in pink #ec008c . On hover
Map needs to be FLAWLESS !! Also require that any imagery must be png and transparent bg.
Must remain exact size as above. Must be extremely accurate on svg coordinates, and optionally would like the STATE text to appear , like the QLD is shown on the image above, but not wholly necessary.
Can anyone point me in the right direction please.
Have you tried Path > Trace Bitmap in Inkscape? If you play with the settings you should be able to get a decent vectorised image.
Vectorised:
EPS:
http://dl.dropbox.com/u/13402937/Australia.eps
Adobe Illustrator:
http://dl.dropbox.com/u/13402937/Australia.ai
try to use this tool, its the potrace part to trace pixelpictures in inkscape with many features. potrace traces pictures from commandline
I have obtained extraordinary results with https://vectormagic.com/ , which can be tried online.
I was looking a component to reduce red eye effect on taken photos. Ive found an image Processing library, but it does not work well at all. I was thinking on brush an image, manually, and only paint if the base pixel color its red or near in RGB.
Have no time now to explain all the process, but i need help to get this idea, or to get a working comp
Thanks in advance!
If you are wishing to manipulate the pixels of an image/component then pixelbender would be a pretty good way to go.
Have a look at http://www.adobe.com/cfusion/exchange/index.cfm?event=productHome&exc=26 for downloadable examples.
These can be run using the toolkit found at http://labs.adobe.com/technologies/pixelbender/
Video tutorials on pixel bender can be found at http://www.gotoandlearn.com/
With this you could change just the required pixel colours to anything and it works with everything in flash (images, canvas, button's etc)