How to get the frame image before play m3u8 video streaming? iOS

Question

I have a demand: get the frame image before play video streaming(m3u8) , as a video preview display. I use AVPlayerItemVideoOutpu copyPixelBufferForItemTime: itemTimeForDisplay: only when play the video streaming to get to the frame image , do you have other method? thanks!!

This is my code :

CMTime itemTime = self.playerItem.currentTime;
CVPixelBufferRef pixelBuffer = [_playerItemVideoOutput copyPixelBufferForItemTime:itemTime itemTimeForDisplay:nil];
CIImage *ciImage = [CIImage imageWithCVPixelBuffer:pixelBuffer];
CIContext *temporaryContext = [CIContext contextWithOptions:nil];
CGImageRef videoImage = [temporaryContext
                                 createCGImage:ciImage
                                 fromRect:CGRectMake(0, 0,
                                                     CVPixelBufferGetWidth(pixelBuffer),
                                                     CVPixelBufferGetHeight(pixelBuffer))];

UIImage *uiImage = [UIImage imageWithCGImage:videoImage];
CGImageRelease(videoImage);
NSLog(@"uiImage：%@", uiImage);

Answer 1

Edit:
I've converted this project to Swift. Here's the new repo ACThumbnailGenerator-Swift.

Usage:

var generator: ACThumbnailGenerator!

func captureSomeImage() {
    let streamUrl = URL(string: "https://p-events-delivery.akamaized.net/18oijbasfvuhbfsdvoijhbsdfvljkb6/m3u8/hls_vod_mvp.m3u8")!
    generator = ACThumbnailGenerator(streamUrl: streamUrl)
    generator.delegate = self
    generator.captureImage(at: 300)
}

func generator(_ generator: ACThumbnailGenerator, didCapture image: UIImage, at position: Double) {
    // Use `image`
}

Original answer:

As you stated in your question, AVPlayerItemVideoOutput is the way to go, BUT, the video does not need to be playing, it just needs to be "ready".

I've created a simple and easy-to-use utility that follows this principle to extract thumbnails from remote streams. (https://github.com/acotilla91/ACThumbnailGenerator)

How to use:

double bitRate = 1000000; // force video bit rate (can be use to cap video quality and improve performance). Pass 0 to use default bit rate.
self.thumbnailGenerator = [[ACThumbnailGenerator alloc] initWithPreferredBitRate:bitRate];

NSURL *videoURL = [NSURL URLWithString:@"http://qthttp.apple.com.edgesuite.net/1010qwoeiuryfg/sl.m3u8"];
int position = 10; // video position (in seconds) from where thumbnail should be extracted. Always pass 0 for live streams.

[self.thumbnailGenerator loadImageFrom:videoURL position:position withCompletionBlock:^(UIImage *image) {

    // use `image`            

}];

Hope it helps.