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    <p><em>This answer is not correct, see the other answers and comments. Original answer left below for posterity.</em></p> <hr> <p><strike>You can't display it directly.</strike> You'll need to convert it to an RGB texture. As you may have gathered from <a href="http://en.wikipedia.org/wiki/YUV" rel="nofollow noreferrer">Wikipedia</a>, there are a bunch of variations on the YUV color space. Make sure you're using the right one.</p> <p>For each pixel, the conversion from YUV to RGB is a straightforward linear transformation. You just do the same thing to each pixel independently.</p> <p>Once you've converted the image to RGB, you can display it by creating a texture. You need to call <a href="http://www.opengl.org/documentation/specs/man_pages/hardcopy/GL/html/gl/gentextures.html" rel="nofollow noreferrer"><code>glGenTextures()</code></a> to allocate a texture handle, <a href="http://www.opengl.org/documentation/specs/man_pages/hardcopy/GL/html/gl/bindtexture.html" rel="nofollow noreferrer"><code>glBindTexture()</code></a> to bind the texture to the render context, and <a href="http://www.opengl.org/documentation/specs/man_pages/hardcopy/GL/html/gl/teximage2d.html" rel="nofollow noreferrer"><code>glTexImage2D()</code></a> to upload the texture data to the GPU. To render it, you again call <code>glBindTexture()</code>, followed by the rendering of a quad with texture coordinates set up properly.</p> <pre><code>// parameters: image: pointer to raw YUV input data // width: image width (must be a power of 2) // height: image height (must be a power of 2) // returns: a handle to the resulting RGB texture GLuint makeTextureFromYUV(const float *image, int width, int height) { float *rgbImage = (float *)malloc(width * height * 3 * sizeof(float)); // check for NULL float *rgbImagePtr = rgbImage; // convert from YUV to RGB (floats used here for simplicity; it's a little // trickier with 8-bit ints) int y, x; for(y = 0; y &lt; height; y++) { for(x = 0; x &lt; width; x++) { float Y = *image++; float U = *image++; float V = *image++; *rgbImagePtr++ = Y + 1.13983f * V; // R *rgbImagePtr++ = Y - 0.39465f * U - 0.58060f * V; // G *rgbImagePtr++ = Y + 2.03211f * U; // B } } // create texture GLuint texture; glGenTextures(1, &amp;texture); // bind texture to render context glBindTexture(GL_TEXTURE_2D, texture); // upload texture data glTexImage2D(GL_TEXTURE_2D, 0, 3, width, height, 0, GL_RGB, GL_FLOAT, rgbImage); // don't use mipmapping (since we're not creating any mipmaps); the default // minification filter uses mipmapping. Use linear filtering for minification // and magnification. glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); // free data (it's now been copied onto the GPU) and return texture handle free(rgbImage); return texture; } </code></pre> <p>To render:</p> <pre><code>glBindTexture(GL_TEXTURE_2D, texture); glBegin(GL_QUADS); glTexCoord2f(0.0f, 0.0f); glVertex3f( 0.0f, 0.0f, 0.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f(64.0f, 0.0f, 0.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f(64.0f, 64.0f, 0.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f( 0.0f, 64.0f, 0.0f); glEnd(); </code></pre> <p>And don't forget to call <code>glEnable(GL_TEXTURE_2D)</code> at some point during initialization, and call <code>glDeleteTextures(1, &amp;texture)</code> during shutdown.</p>
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    1. POHow to display a raw YUV frame in a Cocoa OpenGL program
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    1. USAdam Rosenfield
    1. USAdam Rosenfield
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    1. POHow to display a raw YUV frame in a Cocoa OpenGL program
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    1. COThanks a lot for the information Adam I really appreciate it. Now can you tell me how to extract the raw data file from the hard disk? I am familiar with NSOpenPanel, I can use that to extract the data file path, however, how do I use a file path and load the YUV file into the application?
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    2. COAssuming that the file contains nothing but pixels, you'd simply use NSData or NSFileHandle and read everything. If the file contains metadata such as size information, you're going to have to interpret that using the standard C pointer and/or structure operators.
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      1. USPeter Hosey
    3. COThis answer is incorrect. Starting with MacOS 10.2 and later, every Apple system supports an OpenGL extensions, that can directly load and display YUV data. Search for "GL_YCBCR_422_APPLE" for details. Whether the data is converted somewhere (by the driver in software, on the GPU in hardware, etc.) is none of your business when using this extension (and when the GPU is converting it, trust me, it can beat your code sample of above by at least 1000%)
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