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我一直在嘗試將.h264視頻解碼爲opengl,但我顯示的幀是黑色的。我沒有看到任何錯誤,並且如果我將CMSampleBufferRef中的幀導出到相機膠捲中,它們就沒有問題。iOS - 使用OpenGL ES 2.0進行視頻解碼
也許在openGL方面呢?但是當我顯示圖像而不是視頻時,它可以正常工作,所以不知道在哪裏看。
這裏是給init視頻解碼器的代碼:
- (void)initVideo {
glActiveTexture(GL_TEXTURE0);
glGenTextures(1, &_glTextureHook);
NSURL * url = [NSURL URLWithString:[self.videoMedia getFilePath]];
self.videoAsset = [[AVURLAsset alloc] initWithURL:url options:NULL];
dispatch_semaphore_t sema = dispatch_semaphore_create(0);
[self.videoAsset loadValuesAsynchronouslyForKeys:@[@"tracks"] completionHandler:^{
self.videoTrack = [self.videoAsset tracksWithMediaType:AVMediaTypeVideo][0];
NSString *key = (NSString *) kCVPixelBufferPixelFormatTypeKey;
NSNumber *value = @(kCVPixelFormatType_32BGRA);
NSDictionary *settings = @{key : value};
self.outputVideoTrackOuput = [[AVAssetReaderTrackOutput alloc]
initWithTrack:self.videoTrack outputSettings:settings];
self.assetReader = [[AVAssetReader alloc] initWithAsset:self.videoAsset error:nil];
[self.assetReader addOutput:self.outputVideoTrackOuput];
[self.assetReader startReading];
dispatch_semaphore_signal(sema);
}];
dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER);
}
,並檢索所述OpenGL紋理的代碼中,視頻的每個幀:
- (void)play {
if (self.assetReader.status == AVAssetReaderStatusReading) {
CMSampleBufferRef sampleBuffer = [self.outputVideoTrackOuput copyNextSampleBuffer];
if(sampleBuffer) {
CVImageBufferRef pixelBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
if(pixelBuffer) {
CVPixelBufferLockBaseAddress(pixelBuffer, 0);
glBindTexture(GL_TEXTURE_2D, _glTextureHook);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 1920, 1080, 0, GL_BGRA_EXT, GL_UNSIGNED_BYTE, CVPixelBufferGetBaseAddress(pixelBuffer));
CVPixelBufferUnlockBaseAddress(pixelBuffer, 0);
}
CFRelease(sampleBuffer);
}
}
}
頂點着色器和片段是對於圖像和視頻(與圖像一起使用)相同。我看到的唯一區別是glTexImage2D,其中兩種格式都是GL_RGBA圖像。
我確信,視頻解碼器的_glTextureHook很好地發送到着色器管理器,上下文線程上激活等
這是片段着色器的代碼(這是很基本的,同爲頂點着色器):
precision lowp float;
uniform sampler2D Texture;
varying vec4 DestinationColor;
varying vec2 TexCoordOut;
void main() {
gl_FragColor = DestinationColor * texture2D(Texture, TexCoordOut);
}
你成功成功確實發揮了openGL下的IOS視頻?如果是,你會介意分享代碼嗎?感謝您的提前! – loki
感謝您的代碼,我一直在尋找這樣幾天的具體例子。像@loki問,你有什麼成功?您是否在任何時候都涉及音頻? –