GIF file with hidden images and selectable playback that is activated based on a user ID

A system for playback of an animation file, the system comprising:

• a processor configured to convert a video file to a “.GIF” format representing the video file as a sequence of frames;
• the processor configured to receive a user identification;
• the processor configured to select at least one frame to be swapped based on the user identification;
• the processor configured to swap the selected frame for a substitute image;
• the processor configured to save the video file in “.GIF” format which includes a “selectable frame” GIF application extension and providing the “.GIF” file to a recipient user;
• wherein the video file is viewable in a “.GIF” file viewer configured to playback the modified “.GIF” file with the swapped frame after it (i) parses an application extension of the “.GIF” file by the “.GIF” file viewer, (ii) identifies a recipient user ID from browser cookies, session variables, in-page identifier, or IP address, if the “selectable frame” extension is detected, (iii) swaps the selected frame for the substitute image from sub-blocks of a “selectable frame” GIF application extension into image data block and playing back the “.GIF” file to the recipient, if the user ID provided in the “selectable frame” GIF application extension matches the user ID acquired from the browser cookies, session variables, in-page identifiers or IP address, and (iv) plays back an original “.GIF” file, if the user ID provided in the “selectable frame” GIF application extension is not present or does not match the user ID acquired from the browser cookies, session variables, in-page identifiers or IP address.