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    <p>With my research in these day, I find why <code>CVOpenGLESTextureCacheCreateTextureFromImage</code> cost much time, when the data is big, here is 3M, the <strong>allocation, copy and move operation</strong> which cost is considerable, especially Copy operation. Then with <strong>pixel buffer pool</strong> greatly improve performance of <code>CVOpenGLESTextureCacheCreateTextureFromImage</code> from 30ms to 5ms, the same level with glTexImage2D(). My solution as following:</p> <pre><code>NSMutableDictionary* attributes; attributes = [NSMutableDictionary dictionary]; [attributes setObject:[NSNumber numberWithInt:kCVPixelFormatType_32BGRA] forKey:(NSString*)kCVPixelBufferPixelFormatTypeKey]; [attributes setObject:[NSNumber numberWithInt:videoWidth] forKey: (NSString*)kCVPixelBufferWidthKey]; [attributes setObject:[NSNumber numberWithInt:videoHeight] forKey: (NSString*)kCVPixelBufferHeightKey]; CVPixelBufferPoolCreate(kCFAllocatorDefault, NULL, (CFDictionaryRef) attributes, &amp;bufferPool); CVPixelBufferPoolCreatePixelBuffer (NULL,bufferPool,&amp;pixelBuffer); CVPixelBufferLockBaseAddress(pixelBuffer,0); UInt8 * baseAddress = CVPixelBufferGetBaseAddress(pixelBuffer); memcpy(baseAddress, bgraData, bytesByRow * videoHeight); CVPixelBufferUnlockBaseAddress(pixelBuffer,0); </code></pre> <p>with this new created <strong>pixelBuffer</strong> you can make it fast.</p> <p>Add following configures to <strong>attribtes</strong> can make its performance to the best, less than 1ms.</p> <pre><code> NSDictionary *IOSurfaceProperties = [NSDictionary dictionaryWithObjectsAndKeys: [NSNumber numberWithBool:YES], @"IOSurfaceOpenGLESFBOCompatibility",[NSNumber numberWithBool:YES], @"IOSurfaceOpenGLESTextureCompatibility",nil]; [attributes setObject:IOSurfaceProperties forKey:(NSString*)kCVPixelBufferIOSurfacePropertiesKey]; </code></pre>
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    1. COI implemented this suggestion, adding the surface properties and making use of a pixel buffer pool. But, I am seeing no improvement in the performance on an iPad2. Now my code just runs memcpy() 89% of the time. I do not see how this approach could improve things, since the texture upload is the time critical part of this code. If the pixel data is already sitting in a user buffer, what would be gained by doing another copy to move the memory into a CVPixelBuffer ?
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