Dynamic image content tamper detecting device and system

An electronic watermark detecting method which detects an electronic watermark which includes a plurality of segments configuring continuous predetermined N pieces of frame data, and in which the same electronic watermark is embedded into each of the N pieces of frame data configuring the segment, the method comprising:

• dividing the video content into a plurality of sub-segments, each sub-segment being composed of continuous N/2 pieces of frame data;
• detecting regularity information embedded preliminarily through the electronic watermark from the sub-segments;
• calculating a non-detection count in the case where the electronic watermark is not detected consecutively from the sub-segment and resetting the non-detection count to zero when the electronic watermark is detected;
• calculating a difference value between the regularity information detected from a previous sub-segment and the regularity information detected from a current sub-segment;
• determining falsification of the sub-segment on the basis of the difference value and the non-detection count;
• and
• wherein the regularity information embedded into a first predetermined number of pieces of continuous frame data through the electronic watermark and additional information embedded into a second predetermined number of pieces of continuous frame data through the electronic watermark, are detected through the electronic watermark.

A integrity verification system of video content, the system comprising:

• a content processing apparatus which processes video content which includes a plurality of segments configuring continuous predetermined N pieces of frame data, and in which the same electronic watermark is embedded into each of the N pieces of frame data configuring the segment;
• and
• a content verification apparatus which is coupled to the content processing apparatus through a network and detects falsification of the video content, wherein
• the content processing apparatus includes a unit which divides the video content into a plurality of sub-segments, each sub-segment being composed of continuous N/2 pieces of frame data, a unit which obtains regularity information from outside or inside, and a unit which embeds the obtained regularity information into the sub-segments,
• the content verification apparatus includes a detecting unit which detects the regularity information from the predetermined number of pieces of continuous frame data of the video content through the electronic watermark, a unit which calculates a non-detection count in the case the electronic watermark is not detected from the sub-segment and which resets the non-detection count to zero when the electronic watermark is detected, and a unit which calculates a difference value between the regularity information detected from a previous sub-segment and the regularity information detected from a current sub-segment and a unit which determines falsification of the sub-segment on the basis of the difference value and the non-detection count, and
• wherein the embedding unit embeds the regularity information into a first predetermined number of pieces of continuous frame data through the electronic watermark, and further embeds additional information into a second predetermined number of pieces of continuous frame data through the electronic watermark.