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    <p>Use <code>AVFoundation</code>. I would suggest grabbing frames with <code>AVCaptureVideoDataOutput</code>, then overlaying the captured frame with the watermark image, and finally writing captured and processed frames to a file user <code>AVAssetWriter</code>. </p> <p>Search around stack overflow, there are a ton of fantastic examples detailing how to do each of these things I have mentioned. I haven't seen any that give code examples for exactly the effect you would like, but you should be able to mix and match pretty easily.</p> <p>EDIT:</p> <p>Take a look at these links:</p> <p><a href="https://stackoverflow.com/questions/3331644/iphone-avcapturesession-capture-output-crashing-avcapturevideodataoutput">iPhone: AVCaptureSession capture output crashing (AVCaptureVideoDataOutput)</a> - this post might be helpful just by nature of containing relevant code.</p> <p><code>AVCaptureDataOutput</code> will return images as <code>CMSampleBufferRef</code>s. Convert them to <code>CGImageRef</code>s using this code:</p> <pre><code> - (CGImageRef) imageFromSampleBuffer:(CMSampleBufferRef) sampleBuffer // Create a CGImageRef from sample buffer data { CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer); CVPixelBufferLockBaseAddress(imageBuffer,0); // Lock the image buffer uint8_t *baseAddress = (uint8_t *)CVPixelBufferGetBaseAddressOfPlane(imageBuffer, 0); // Get information of the image size_t bytesPerRow = CVPixelBufferGetBytesPerRow(imageBuffer); size_t width = CVPixelBufferGetWidth(imageBuffer); size_t height = CVPixelBufferGetHeight(imageBuffer); CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); CGContextRef newContext = CGBitmapContextCreate(baseAddress, width, height, 8, bytesPerRow, colorSpace, kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst); CGImageRef newImage = CGBitmapContextCreateImage(newContext); CGContextRelease(newContext); CGColorSpaceRelease(colorSpace); CVPixelBufferUnlockBaseAddress(imageBuffer,0); /* CVBufferRelease(imageBuffer); */ // do not call this! return newImage; } </code></pre> <p>From there you would convert to a UIImage, </p> <pre><code> UIImage *img = [UIImage imageWithCGImage:yourCGImage]; </code></pre> <p>Then use </p> <pre><code>[img drawInRect:CGRectMake(x,y,height,width)]; </code></pre> <p>to draw the frame to a context, draw a PNG of the watermark over it, and then add the processed images to your output video using <code>AVAssetWriter</code>. I would suggest adding them in real time so you're not filling up memory with tons of UIImages. </p> <p><a href="https://stackoverflow.com/questions/3741323/how-do-i-export-uiimage-array-as-a-movie">How do I export UIImage array as a movie?</a> - this post shows how to add the UIImages you have processed to a video for a given duration.</p> <p>This should get you well on your way to watermarking your videos. Remember to practice good memory management, because leaking images that are coming in at 20-30fps is a great way to crash the app.</p>
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    1. POiPhone Watermark on recorded Video.
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    1. COThank you James, if you can provide me a start it would be great.. Thanks again.
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    2. COSee my additional comments above.
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    3. COhave you had a chance to try any of this out yet? any luck?
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