En utilisant opengl es shader pour convertir YUV RVB

Je veux convertir yuv rvb en opengl es shader avec juste un échantillonneur qui contient yuv données. Mon code est ci-dessous:

1) - je envoyer yuv données de texture:

GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_LUMINANCE,
            mData.w, mData.h * 3 /2, 0, GLES20.GL_LUMINANCE,
            GLES20.GL_UNSIGNED_BYTE, ByteBuffer.wrap(mData.yuv));

2) Mon vertex shader:

attribute vec4 position;
attribute vec2 inputTextureCoordinate;
attribute mediump float width;

varying vec2 v_texCoord;
varying mediump vec2 v_vuTexCoord;
varying mediump float x_coord;

void main()
{
    gl_Position = position;
    v_texCoord = vec2(inputTextureCoordinate.x, inputTextureCoordinate.y * 0.6666667);
    v_vuTexCoord = vec2(inputTextureCoordinate.x, inputTextureCoordinate.y * 0.333333 + 0.6666667);
    x_coord = floor(inputTextureCoordinate.x * width);
}

3) Mon fragment shader:

uniform sampler2D inputImageTexture;  
varying mediump vec2 v_texCoord;
varying mediump vec2 v_vuTexCoord;
varying mediump float x_coord;
uniform mediump float u_one_over_tex_size;

void main()
{
    mediump vec3 yuv;
    mediump vec3 rgb;
    mediump float valx = mod(x_coord , 2.0);
    if(valx < 1.0) 
    {
        yuv.y = texture2D(inputImageTexture, v_vuTexCoord + vec2(u_one_over_tex_size, 0)).r - 0.5;
        yuv.z = texture2D(inputImageTexture, v_vuTexCoord).r - 0.5;
    } 
    else {
        yuv.y = texture2D(inputImageTexture, v_vuTexCoord).r - 0.5;
        yuv.z = texture2D(inputImageTexture, v_vuTexCoord + vec2(u_one_over_tex_size, 0)).r - 0.5;
    }
    yuv.x = texture2D(inputImageTexture, v_texCoord).r;
    rgb = mat3(    1,       1,     1,
                   0, -.34413, 1.772,
               1.402, -.71414,     0) * yuv;
    gl_FragColor = vec4(rgb, 1);
}

Mais le résultat n'est pas que je ne le pensais. Si je divise yuv données pour y et uv échantillonneurs et changement de vertex et fragment shader, et je peux avoir le bon résultat. Mais comment pouvais-je seulement envoyer un sampler juste
comme ci-dessus?

J'ai trouvé quelques informations intéressantes dans ce site code.google.com/p/o3d/source/browse/trunk/samples_webgl/shaders/...

OriginalL'auteur The Lord Of Ring | 2013-06-14

  1. 5

    Ont un oeil sur le code ici: http://www.fourcc.org/source/YUV420P-OpenGL-GLSLang.c

    /*
 * Very simple example of how to perform YUV->RGB (YCrCb->RGB)
 * conversion with an OpenGL fragmen shader. The data (not included)
 * is presumed to be three files with Y, U and V samples for a 720x576
 * pixels large image.
 *
 * Note! The example uses NVidia extensions for rectangular textures
 * to make it simpler to read (non-normalised coordinates).
 * Rewriting it without the extensions is quite simple, but left as an
 * exercise to the reader. (The trick is that the shader must know the
 * image dimensions instead)
 *
 * The program also does not check to see if the shader extensions are
 * available - this is after all just a simple example.
 *
 * This code is released under a BSD style license. Do what you want, but
 * do not blame me.
 *
 * Peter Bengtsson, Dec 2004.
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <GL/gl.h>
#include <GL/glext.h>
#include <SDL/SDL.h>

int Quit=0;

static int B_WIDTH=640;
static int B_HEIGHT=480;

int main(int cnt,char *arg[])
{
SDL_Surface *Win=NULL;
GLubyte *Ytex,*Utex,*Vtex;
SDL_Event evt;
int i;
GLhandleARB FSHandle,PHandle;
char *s;
FILE *fp;

char *FProgram=
  "uniform sampler2DRect Ytex;\n"
  "uniform sampler2DRect Utex,Vtex;\n"
  "void main(void) {\n"
  "  float nx,ny,r,g,b,y,u,v;\n"
  "  vec4 txl,ux,vx;"
  "  nx=gl_TexCoord[0].x;\n"
  "  ny=576.0-gl_TexCoord[0].y;\n"
  "  y=texture2DRect(Ytex,vec2(nx,ny)).r;\n"
  "  u=texture2DRect(Utex,vec2(nx/2.0,ny/2.0)).r;\n"
  "  v=texture2DRect(Vtex,vec2(nx/2.0,ny/2.0)).r;\n"

  "  y=1.1643*(y-0.0625);\n"
  "  u=u-0.5;\n"
  "  v=v-0.5;\n"

  "  r=y+1.5958*v;\n"
  "  g=y-0.39173*u-0.81290*v;\n"
  "  b=y+2.017*u;\n"

  "  gl_FragColor=vec4(r,g,b,1.0);\n"
  "}\n";


if(!SDL_Init(SDL_INIT_VIDEO)) {

  SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER,1);

  Win=SDL_SetVideoMode(B_WIDTH,B_HEIGHT,32,SDL_HWSURFACE|SDL_ANYFORMAT|SDL_OPENGL);

  if(Win) {
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glOrtho(0,B_WIDTH,0,B_HEIGHT,-1,1);
    glViewport(0,0,B_WIDTH,B_HEIGHT);
    glClearColor(0,0,0,0);
    glColor3f(1.0,0.84,0.0);
    glHint(GL_POLYGON_SMOOTH_HINT,GL_NICEST);

    /* Set up program objects. */
    PHandle=glCreateProgramObjectARB();
    FSHandle=glCreateShaderObjectARB(GL_FRAGMENT_SHADER_ARB);

    /* Compile the shader. */
    glShaderSourceARB(FSHandle,1,&FProgram,NULL);
    glCompileShaderARB(FSHandle);

    /* Print the compilation log. */
    glGetObjectParameterivARB(FSHandle,GL_OBJECT_COMPILE_STATUS_ARB,&i);
    s=malloc(32768);
    glGetInfoLogARB(FSHandle,32768,NULL,s);
    printf("Compile Log: %s\n", s);
    free(s);

    /* Create a complete program object. */
    glAttachObjectARB(PHandle,FSHandle);
    glLinkProgramARB(PHandle);

    /* And print the link log. */
    s=malloc(32768);
    glGetInfoLogARB(PHandle,32768,NULL,s);
    printf("Link Log: %s\n", s);
    free(s);

    /* Finally, use the program. */
    glUseProgramObjectARB(PHandle);

    /* Load the textures. */
    Ytex=malloc(414720);
    Utex=malloc(103680);
    Vtex=malloc(103680);

    fp=fopen("Image.Y","rb");
    fread(Ytex,414720,1,fp);
    fclose(fp);
    fp=fopen("Image.U","rb");
    fread(Utex,103680,1,fp);
    fclose(fp);
    fp=fopen("Image.V","rb");
    fread(Vtex,103680,1,fp);
    fclose(fp);

    /* This might not be required, but should not hurt. */
    glEnable(GL_TEXTURE_2D);

    /* Select texture unit 1 as the active unit and bind the U texture. */
    glActiveTexture(GL_TEXTURE1);
    i=glGetUniformLocationARB(PHandle,"Utex");
    glUniform1iARB(i,1);  /* Bind Utex to texture unit 1 */
    glBindTexture(GL_TEXTURE_RECTANGLE_NV,1);

    glTexParameteri(GL_TEXTURE_RECTANGLE_NV,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
    glTexParameteri(GL_TEXTURE_RECTANGLE_NV,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
    glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_DECAL);
    glTexImage2D(GL_TEXTURE_RECTANGLE_NV,0,GL_LUMINANCE,376,288,0,GL_LUMINANCE,GL_UNSIGNED_BYTE,Utex);

    /* Select texture unit 2 as the active unit and bind the V texture. */
    glActiveTexture(GL_TEXTURE2);
    i=glGetUniformLocationARB(PHandle,"Vtex");
    glBindTexture(GL_TEXTURE_RECTANGLE_NV,2);
    glUniform1iARB(i,2);  /* Bind Vtext to texture unit 2 */

    glTexParameteri(GL_TEXTURE_RECTANGLE_NV,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
    glTexParameteri(GL_TEXTURE_RECTANGLE_NV,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
    glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_DECAL);
    glTexImage2D(GL_TEXTURE_RECTANGLE_NV,0,GL_LUMINANCE,376,288,0,GL_LUMINANCE,GL_UNSIGNED_BYTE,Vtex);

    /* Select texture unit 0 as the active unit and bind the Y texture. */
    glActiveTexture(GL_TEXTURE0);
    i=glGetUniformLocationARB(PHandle,"Ytex");
    glUniform1iARB(i,0);  /* Bind Ytex to texture unit 0 */
    glBindTexture(GL_TEXTURE_RECTANGLE_NV,3);

    glTexParameteri(GL_TEXTURE_RECTANGLE_NV,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
    glTexParameteri(GL_TEXTURE_RECTANGLE_NV,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
    glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_DECAL);
    glTexImage2D(GL_TEXTURE_RECTANGLE_NV,0,GL_LUMINANCE,752,576,0,GL_LUMINANCE,GL_UNSIGNED_BYTE,Ytex);

    /* Simple loop, just draws the image and waits for quit. */
    while(!Quit) {
      if(SDL_PollEvent(&evt)) {
        switch(evt.type) {
        case  SDL_KEYDOWN:
        case  SDL_QUIT:
          Quit=1;
        break;
        }
      }

      glClear(GL_COLOR_BUFFER_BIT);

      /* Draw image (again and again). */

      glBegin(GL_QUADS);
        glTexCoord2i(0,0);
        glVertex2i(0,0);
        glTexCoord2i(720,0);
        glVertex2i(B_WIDTH,0);
        glTexCoord2i(720,576);
        glVertex2i(B_WIDTH,B_HEIGHT);
        glTexCoord2i(0,576);
        glVertex2i(0,B_HEIGHT);
      glEnd();

      /* Flip buffers. */

      glFlush();
      SDL_GL_SwapBuffers();

      sleep(1);
    } /* while(!Quit) */

    /* Clean up before exit. */

    glUseProgramObjectARB(0);
    glDeleteObjectARB(sprog);

    free(Ytex);
    free(Utex);
    free(Vtex);

  } else {
    fprintf(stderr,"Unable to create primary surface. \"%s\".\n",SDL_GetError());
  }
  SDL_Quit();
} else {
  fprintf(stderr,"Initialisation failed. \"%s\".\n",SDL_GetError());
}

return(0);
}
    Qui ressemble encore il fractionnement de la la Y et UV des avions et de les soumettre, en tant que textures distinctes, dont le demandeur dispose déjà de travail. Ils essaient de trouver un moyen de prendre un seul YUV cadre et analyser que pour convertir RVB.
    De sorte qu'il n'. My bad, je vais le supprimer.
    si la valeur de r,g,b est supérieur à 1,0 , que devons-nous faire? @FredrikPihl

    OriginalL'auteur Fredrik Pihl

  2. 0

    Est peut-être hors-sujets, mais ici j'ai mis en place une YUV 4:2:2 v210 10 bits décodeur en GLSL.

    OriginalL'auteur Mouze