@nic

Here is a GLSL shader, that will unwarp a 'fisheye' (its not going to be perfect, since its not calibrated to any specific lens), but it should provide a decent result.

/*
Fisheye Correction - Fragment Shader
For Isadora GLSL Shader actor
*/
// ISADORA_PLUGIN_NAME("Fisheye Correction")
// ISADORA_PLUGIN_DESC("Corrects fisheye lens distortion from an input video stream to create a flatter, non-fisheye output.")
// ISADORA_FLOAT_PARAM(strength, strn, 0.0, 200.0, 100.0, "Amount of fisheye correction. Higher values remove more barrel distortion.")
uniform float strength;
// ISADORA_FLOAT_PARAM(zoom, zoom, 50.0, 200.0, 115.0, "Zooms the corrected image to hide curved black edges.")
uniform float zoom;
// ISADORA_FLOAT_PARAM(horz_center, ctrx, -100.0, 100.0, 0.0, "Horizontal center of the lens correction.")
uniform float horz_center;
// ISADORA_FLOAT_PARAM(vert_center, ctry, -100.0, 100.0, 0.0, "Vertical center of the lens correction.")
uniform float vert_center;
// ISADORA_FLOAT_PARAM(edge_softness, edge, 0.0, 20.0, 2.0, "Softens the edge where the corrected image runs outside the source.")
uniform float edge_softness;
// Built-in Isadora uniforms
uniform vec2 resolution;
uniform sampler2D tex0;
void main(void)
{
    vec2 uv = gl_TexCoord[0].xy;
    // Move coordinates so that 0,0 is the image center.
    vec2 center = vec2(0.5) + vec2(horz_center, vert_center) / 200.0;
    vec2 p = uv - center;
    // Correct for non-square aspect ratio.
    float aspect = resolution.x / resolution.y;
    p.x *= aspect;
    // Zoom after correction. Higher zoom crops the outer edges.
    p /= zoom / 100.0;
    // Distance from lens center.
    float r = length(p);
    // Barrel/fisheye correction.
    // The shader samples farther outward as pixels move from the center,
    // which visually straightens fisheye-curved lines.
    float k = strength / 100.0;
    float corrected_r = r * (1.0 + k * r * r);
    vec2 corrected_p = p;
    if (r > 0.00001) {
        corrected_p = normalize(p) * corrected_r;
    }
    // Undo aspect correction and return to texture coordinates.
    corrected_p.x /= aspect;
    vec2 sample_uv = corrected_p + center;
    // Create a soft mask so out-of-range areas fade to black.
    float soft = edge_softness / 100.0;
    float mask_x = smoothstep(0.0, soft, sample_uv.x) *
                   smoothstep(0.0, soft, 1.0 - sample_uv.x);
    float mask_y = smoothstep(0.0, soft, sample_uv.y) *
                   smoothstep(0.0, soft, 1.0 - sample_uv.y);
    float mask = mask_x * mask_y;
    // Clamp sampling to avoid texture wrapping artifacts.
    sample_uv = clamp(sample_uv, vec2(0.0), vec2(1.0));
    vec4 color = texture2D(tex0, sample_uv);
    gl_FragColor = vec4(color.rgb * mask, color.a);
}

Hi all, 

Does anyone know a way to undistort a feed from a fisheye lens? I know there is an actor to create a fisheye effect, but I wondered if there is some way of undoing the distortion?

Nic

I like the Blackmagic Decklink Quad (8 switchable in/out). It's under Capture and Playback, here: Products | Blackmagic Design

The one I have seems to have been replaced by a newer version, but I found it on eBay: Blackmagic Design BMDPCB143A DeckLink Quad PCIe SDI Capture Card | eBay

Cheers,

Hugh

Get a datapath FX4 or similar. It takes a single 4k input and splits it into quads; then you get 4 individual FHD outputs.https://www.datapath.co.uk/dat... 

Hi all

Does anyone have any tips for running 12 or more projectors from one computer? I already have an rtx 4090 and an rtx 3070 installed but want to run at least 4 more projectors . 

Thanks,

Ray

@ubik

Is it possible you are low on drive space?

Hi all!

I made a live gig with a patch and it went really smooth during the whole performance. During preparations the cpu load was about 35%.

Now, a few weeks later, the performance is much worse, even on the same unedited save files. I don't get what could be wrong.

Appearance: Annoying stutters every 10 seconds

CPU load: 60-70%

Framerate:  about 24-27 (frame rate goal 30fps)

VPO: 150-179

Cycles: 0.70

The patch consists of many GLSL shaders, some feedback looping and a few virtual projectors. All other applications are closed.

Anyone want to take a shot at guessing what could have happened?

@woland

Magnificent indeed!!! Perhaps they'll be reintroduced: there's quite a strong guerrilla rewilding movement here in the UK...

@mark_m said:

We don't do a lot of Coyote Hog Predator hunting in London, which is maybe why it's no longer available.

They must have been hunted to extinction in London then. What a shame. Such majestic creatures.

@woland said:

do you have any insights about IR flashlights that you can share?

Sorry, none! I just bought some off Amazon. The one I got isn't available any more. It was described as "Mini IR Illuminator Torch, 5W 850nm Focus Adjustable IR Led Flashlight Infrared Light Torch for Night Vision, Coyote Hog Predator Hunting (AA Battery not Included) "  We don't do a lot of Coyote Hog Predator hunting in London, which is maybe why it's no longer available.