小编Ian*_*bey的帖子

我正在使用GPUImageHoughTransformLineDetector来尝试检测图像中突出显示的文本:

我使用以下代码来尝试检测边界蓝框线:

GPUImagePicture *stillImageSource = [[GPUImagePicture alloc] initWithImage:rawImage];
GPUImageHoughTransformLineDetector *lineFilter = [[GPUImageHoughTransformLineDetector alloc] init];
[stillImageSource addTarget:lineFilter];
GPUImageLineGenerator *lineDrawFilter = [[GPUImageLineGenerator alloc] init];
[lineDrawFilter forceProcessingAtSize:rawImage.size];

__weak typeof(self) weakSelf = self;
[lineFilter setLinesDetectedBlock:^(GLfloat *flt, NSUInteger count, CMTime time) {
    NSLog(@"Number of lines: %ld", (unsigned long)count);
    GPUImageAlphaBlendFilter *blendFilter = [[GPUImageAlphaBlendFilter alloc] init];
    [blendFilter forceProcessingAtSize:rawImage.size];
    [stillImageSource addTarget:blendFilter];
    [lineDrawFilter addTarget:blendFilter];

    [blendFilter useNextFrameForImageCapture];
    [lineDrawFilter renderLinesFromArray:flt count:count frameTime:time];
    weakSelf.doneProcessingImage([blendFilter imageFromCurrentFramebuffer]);
}];
[stillImageSource processImage];

无论edgeThreshold还是1023行,每次运行此命令时,结果输出如下所示:

我不清楚为什么改变门槛没有做任何事情,但我确信我误解了一些事情.任何人对如何做到这一点有任何想法？