APNG Anime Maker is a program to create animated PNG files. It is very easy to use and freeware, making it popular among digital artist, especially those who draw anime.
Delay: Enter a number in delay box and click "msec" or "fps" to set the delay time for the selected frames, you can set "All" apply to all frames.
Offset and Increment: Offset is X and Y position at which to render the selected frames, Increment X and Y auto increase the offset for the following selected frames.
None: No disposal is done on this frame before rendering the next; the contents of the output buffer are left as is.
Background: The frame's region of the output buffer is to be cleared to fully transparent black before rendering the next frame.
Previous: The frame's region of the output buffer is to be reverted to the previous contents before rendering the next frame.
Source: All color components of the frame, including alpha, overwrite the current contents of the frame's output buffer region.
Over: The frame should be composite onto the output buffer based on its alpha, using a simple OVER operation.
It optimize the file size of the animation. It is designed for movie clip with small scene change. Set "Lossy" to have more compression, "Tolerance" affect between file size and quality. Set "Selected Region Only", then drag a region in the image preview with scene change. Optimize will only search in the region selected. It can give more compression for lossy movie. "Selected Image Only" optimize the image selected only. Loop: Number of times to loop the animation. 0 indicates infinite looping. Compression Level: Set the compression level of the PNG.