Decode GIF animaion into images with OpenCV and GIFLIB

GifPlayer.cpp

#include <iostream>
#include <opencv2/opencv.hpp>  
#include <gif_lib.h>

int main(int ac, char **av)
{
	int err;
	GifFileType *f = DGifOpenFileName("test.gif", &err);
	assert(f != NULL);
	int ret = DGifSlurp(f);
	assert(ret == GIF_OK);
	int width = f->SWidth;
	int height = f->SHeight;

	std::cout << "Total Frames:     " << f->ImageCount << std::endl;
	std::cout << "Image Size:       " << width << " X " << height << std::endl;
	std::cout << "Color Resolution: " << f->SColorResolution << std::endl;

	GifColorType *colorMap = f->SColorMap->Colors;

	cv::namedWindow("image");
	cv::Mat img(height, width, CV_8UC3);

	// Play for 100 frames ...
	for (int t = 0; t < 100; t++) {
		int frameNo = t % f->ImageCount;
		std::cout << frameNo << " / " << f->ImageCount << std::endl;
		SavedImage *image = &f->SavedImages[frameNo];
		auto *ptr = img.ptr<cv::Vec3b>();
		for (int i = 0; i < width * height; i++, ptr++) {
			const GifColorType &color = colorMap[image->RasterBits[i]];
			*ptr = cv::Vec3b(color.Red, color.Green, color.Blue);
		}
		cvtColor(img, img, CV_RGB2BGR);
		imshow("image", img);
		cv::waitKey(100);
	}

	DGifCloseFile(f, &err);
	return 0;
}