Composite still-image creating device capable of creating a still image from moving images
Each of the frames forming moving images is decoded in sequence and while a candidate frame is decoded, a decision is made as to whether or not the motion vector variable-length decoded for each macroblock is greater than a threshold, so that if the motion vector is greater than the threshold, the decoded image of the corresponding block is decided as a partial image forming a subject portion that had motion in the candidate frame and then combined with a base image stored in a still memory in a combining unit, whereby, by repeating this process, a composite still image which allows the motion of the subject to be grasped visually is created in the still memory.
1. A composite still image creation device comprising:
an acquisition unit which acquires moving image data coded using an interframe predictive coding process, the moving image data including motion vector data;
an extraction unit which extracts the motion vector data from the moving image data acquired by the acquisition unit;
a selection unit which selects a partial image in a frame image included in the moving image data based on the motion vector data extracted by the extraction unit;
a combining unit which combines partial images selected by the selection unit to form a still image;
a calculation unit which calculates frame motion vector data indicating a tendency of overall motion of the regions of the frame image, based on the respective motion vector data of the regions in one frame image; and
a correction unit which, based on the frame motion vector data calculated by the calculation unit, corrects a combined position with respect to the still image formed by the combining unit.
2. A composite still image creation device comprising:
means for acquiring moving image data coded using an interframe predictive coding process, the moving image data including motion vector data;
means for extracting the motion vector data from the moving image data acquired by the acquisition means;
means for selecting a partial image in a frame image included in the moving image data based on the motion vector data extracted by the extraction means;
means for combining partial images selected by the selection means to form a still image;
means for calculating frame motion vector data indicating a tendency of overall motion of the regions of the frame image, based on the respective motion vector data of the regions in one frame image; and
means for correcting, based on the frame motion vector data calculated by the calculation means, a combined position with respect to the still image formed by the combining means.
3. A composite still image creation method comprising:
operating a still image creation device to acquire moving image data coded using an interframe predictive coding process, the moving image data including motion vector data;
extracting the motion vector data from the acquired moving image data;
selecting a partial image in a frame image included in the moving image data based on the extracted motion vector data;
combining the selected partial images to form a still image;
calculating frame motion vector data indicating a tendency of overall motion of the regions of the frame image, based on the respective motion vector data of the regions in one frame image; and
correcting, based on the calculated frame motion vector data, a combined position with respect to the still image which is formed by combining the selected partial images.
4. A recording storage medium storing a computer program which is executable by a computer to function as:
means for acquiring moving image data coded using an interframe predictive coding process, the moving image data including motion vector data;
means for extracting the motion vector data from the moving image data acquired by the acquisition means;
means for selecting a partial image in a frame image included in the moving image data based on the motion vector data extracted by the extraction means;
means for combining partial images selected by the selection means to form a still image;
means for calculating frame motion vector data indicating a tendency of overall motion of the regions of the frame image, based on the respective motion vector data of the regions in one frame image; and
means for correcting, based on the frame motion vector data calculated by the calculation means, a combined position with respect to the still image formed by the combining means.