Selective video modification

A data processing system for processing a video stream comprising:

• at least one processor;
• and
• storage comprising computer-executable instructions which, when executed by the at least one processor, cause the at least one processor to:
• receive a video stream comprising a plurality of frames of image data;
• selecting portions of the image data on the basis of first data indicating locations within the image data;
• modify the selected portions to generate modified portions of the image data;
• generate second data for use in recovering at least some of the selected portions from the modified portions, the second data comprising metadata representing an expiry date value for the second data, the expiry date value indicating a date and/or time at which access to the second data is to expire;
• output the second data, unselected portions of the image data and the modified portions of the image data;
• provide the modified portions of the image data and the unselected portions of the image data to a user at a first time by transmitting the modified portions of the image data and the unselected portions of the image data to a data processing system operated by the user;
• and
• at a second time, the second time being after the first time:
• receive a request to provide the second data to the user;
• compare the expiry date value for the second data with a reference date value;
• and
• perform a predetermined action in dependence on the comparison of the expiry date value with the reference date value,
• wherein if it is determined that the expiry date value represents a later date and/or time than the reference date value based on the comparison, the predetermined action comprises providing the second data to the user by transmitting the second data to the data processing system operated by the user.

A non-transitory computer-readable storage medium comprising computer-executable instructions which, when executed by at least one processor, cause the at least one processor to:

• receive a video stream comprising a plurality of frames of image data;
• selecting portions of the image data on the basis of first data indicating locations within the image data;
• modify the selected portions to generate modified portions of the image data;
• generate second data for use in recovering at least some of the selected portions from the modified portions, the second data comprising metadata representing an expiry date value for the second data, the expiry date value indicating a date and/or time at which access to the second data is to expire;
• and
• output the second data, unselected portions of the image data and the modified portions of the image data;
• provide the modified portions of the image data and the unselected portions of the image data to a user at a first time by transmitting the modified portions of the image data and the unselected portions of the image data to a data processing system operated by the user;
• and
• at a second time, the second time being after the first time:
• receive a request to provide the second data to the user;
• compare the expiry date value for the second data with a reference date value;
• and
• perform a predetermined action in dependence on the comparison of the expiry date value with the reference date value,
• wherein if it is determined that the expiry date value represents a later date and/or time than the reference date value based on the comparison, the predetermined action comprises providing the second data to the user by transmitting the second data to the data processing system operated by the user.