precision mediump float;
uniform sampler2D m_sampY;
uniform sampler2D m_sampU;
uniform sampler2D m_sampV;
varying vec2      m_cordY;
varying vec2      m_cordU;
varying vec2      m_cordV;
uniform float     m_alpha;
uniform mat4      m_yuvmat;

void main()
{
  vec4 yuv, rgb;
  yuv.rgba = vec4(texture2D(m_sampY, m_cordY).r, texture2D(m_sampU, m_cordU).r, texture2D(m_sampV, m_cordV).r, 1.0);

  rgb   = m_yuvmat * yuv;
  rgb.a = m_alpha;
  gl_FragColor = rgb;
}