Recheck the animated canvas calculation logic, fix the issue of that calculation

[dreampiggy]

Continue Fix to #22 .

This time it works...The logic need to be replaced from this:

 // Draw from range: [startIndex, endIndex) if (endIndex > startIndex) { do { @autoreleasepool { [self sd_blendWebpImageWithCanvas:_canvas iterator:iter colorSpace:_colorSpace]; } } while ((size_t)iter.frame_num < (endIndex + 1) && WebPDemuxNextFrame(&iter)); }

To:

 // Draw from range: [startIndex, endIndex) if (endIndex > startIndex) { do { @autoreleasepool { [self sd_blendWebpImageWithCanvas:_canvas iterator:iter colorSpace:_colorSpace]; } } while ((size_t)iter.frame_num < endIndex && WebPDemuxNextFrame(&iter)); } // libwebp's index start with 1 if (!WebPDemuxGetFrame(_demux, (int)(index + 1), &iter)) { WebPDemuxReleaseIterator(&iter); return nil; }

See screenshot video:

Screenshot.mp4.zip