splash screen with user renderTarget to get CVPixelBufferRef

[lansefengxinzi]

i use GPUImageRawData renderTarget to get CVPixelBufferRef，but splash screen。 self.lastFilter.frameProcessingCompletionBlock = ^(GPUImageOutput *output, CMTime time) { __strong typeof(wself) strongSelf = wself;

    GPUImageFramebuffer *imageFramebuffer = output.framebufferForOutput;
    CVPixelBufferRef pixelBuffer =imageFramebuffer.pixelBuffer;
    if (pixelBuffer) {
        CVPixelBufferLockBaseAddress(pixelBuffer, 0);
        CVPixelBufferRetain(pixelBuffer);
        // 发送视频数据
        。。。
        CFRelease(pixelBuffer);
    }

};