YUV to RGBA GL Shader

YUV2RGBA.glsl

uniform sampler2D texY; // Y
uniform sampler2D texU; // U
uniform sampler2D texV; // V

varying vec2 vary_tex_cord;

vec3 yuv2rgb(in vec3 yuv)
{
    // YUV offset
    // const vec3 offset = vec3(-0.0625, -0.5, -0.5);
    const vec3 offset = vec3(-0.0625, -0.5, -0.5);
    // RGB coefficients
    const vec3 Rcoeff = vec3( 1.164, 0.000,  1.596);
    const vec3 Gcoeff = vec3( 1.164, -0.391, -0.813);
    const vec3 Bcoeff = vec3( 1.164, 2.018,  0.000);

    vec3 rgb;

    yuv = clamp(yuv, 0.0, 1.0);

    yuv += offset;

    rgb.r = dot(yuv, Rcoeff);
    rgb.g = dot(yuv, Gcoeff);
    rgb.b = dot(yuv, Bcoeff);
    return rgb;
}


vec3 get_yuv_from_texture(in vec2 tcoord)
{
    vec3 yuv;
    yuv.x = texture(texY, tcoord).r;
    // Get the U and V values
    yuv.y = texture(texU, tcoord).r;
    yuv.z = texture(texV, tcoord).r;
    return yuv;
}

vec4 mytexture2D(in vec2 tcoord)
{
    vec3 rgb, yuv;
    yuv = get_yuv_from_texture(tcoord);
    // Do the color transform
    rgb = yuv2rgb(yuv);
    return vec4(rgb, 1.0);
}

out vec4 out_color;

void main()
{
    // That was easy. :)
    out_color = mytexture2D(vary_tex_cord);
}

Hello,
Thanks for sharing this.
That could help me for my project. I'm receiving a YUV 4.2.2 buffer and I would like to display it on a RGB texture OpenGL. It would be better to decode it Hardware by GPU with this shader.

Please could you help me using this shader ? Is this a Fragment Shader ? Do you have a sample code how to use it ?

Thanks a lot

precision lowp float;
uniform sampler2D samplerY;
uniform sampler2D samplerU;
uniform sampler2D samplerV;
varying vec2 v_texCoord;

void main() {
    float r, g, b, y, u, v, fYmul;
    
    vec3 rgb, yuv;

    yuv.x = texture2D(samplerY, v_texCoord).r;
    yuv.y = texture2D(samplerU, v_texCoord).r;
    yuv.z = texture2D(samplerV, v_texCoord).r;
    
    const vec3 offset = vec3(-0.0625, -0.5, -0.5);
    // RGB coefficients
    const vec3 Rcoeff = vec3( 1.164, 0.000,  1.596);
    const vec3 Gcoeff = vec3( 1.164, -0.391, -0.813);
    const vec3 Bcoeff = vec3( 1.164, 2.018,  0.000);
    
    yuv = clamp(yuv, 0.0, 1.0);
    yuv += offset;

    rgb.r = dot(yuv, Rcoeff);
    rgb.g = dot(yuv, Gcoeff);
    rgb.b = dot(yuv, Bcoeff);
    gl_FragColor = vec4(rgb, 1.0);
}

@AhmedX6 I need to do the same. How did you convert from 4:2:2 to per pixel yuv values?

const char gFragmentNV12ToRGB[] =
    "#version 320 es\n"
    "precision highp float;\n"
    "in vec2 TexCoords;\n"
    "out vec4 color;\n"
    "uniform sampler2D text;\n"
    "layout(binding = 0) uniform sampler2D textureY;\n"
    "layout(binding = 1) uniform sampler2D textureUV;\n"
    "void main() {\n"
    "   float r, g, b, y, u, v;\n"
    "   y = texture(textureY, TexCoords).r;\n"
    "   u = texture(textureUV, TexCoords).r - 0.5;\n"
    "   v = texture(textureUV, TexCoords).a - 0.5;\n"
    "   r = y + 1.13983 * v;\n"
    "   g = y - 0.39465 * u - 0.58060 * v;\n"
    "   b = y + 2.03211 * u;\n"
    "   color = vec4(r, g, b, 1.0);\n"
    "}\n";

I used this one