Skipping frames for Animated WebP

It would be good to have an option to skip frames for animated webP.
If I have a thumbnail trying to render an animated wepb image with 120 frames it could be good to render only 30 frames, to preserve speed and memory.
Maybe not the first 30 frames but skipping frames in a loop: the animation will not be very smooth obviously.

A simple, not nice looking solution to skip half of the frames:
SDImageWebPCoder.m
line 264
Adding a skipper in the loop and duplicating the duration

    int skipper = 0;
    do {
        skipper++;
        if ((skipper %2) == 0) {
            continue;
        }
            
        @autoreleasepool {
            CGImageRef imageRef = [self sd_drawnWebpImageWithCanvas:canvas iterator:iter colorSpace:colorSpace scaledSize:scaledSize];
            if (!imageRef) {
                continue;
            }

#if SD_UIKIT || SD_WATCH
            UIImage *image = [[UIImage alloc] initWithCGImage:imageRef scale:scale orientation:UIImageOrientationUp];
#else
            UIImage *image = [[UIImage alloc] initWithCGImage:imageRef scale:scale orientation:kCGImagePropertyOrientationUp];
#endif
            CGImageRelease(imageRef);
            
            NSTimeInterval duration = [self sd_frameDurationWithIterator:iter];
            SDImageFrame *frame = [SDImageFrame frameWithImage:image duration:(duration*2)];
            [frames addObject:frame];
        }
        
    } while (WebPDemuxNextFrame(&iter));

从 SDImageWebPCoder.m 中大约第 264 行开始，这里会解码动画 WebP 帧并收集其持续时间。确定应如何在受支持的 Apple 平台上公开并保留一个选择性启用的帧跳过选项，然后使用动画 WebP fixture 验证最终的帧数和动画时序。