Portable terminal, video data repair method and program
A portable terminal wherein the amount of processing and power consumption when performing repair is reduced and video data can be reliably repaired, and video data repair method and program of the same. The portable terminal is provided with a video data repairer that repairs video data in which video is poor by replacing it with a portion of video data acquired from an external source, said video data repairer saving, without deleting at the time of repairing, all of partial video data necessary to decode subsequent video data continuing after the video data to be repaired, and performing control so that only the portion of the video data that is repaired is re-encoded.
1. A portable terminal that saves video data encrypted by a method of superimposing a result of encoding a previous video data clear text block upon a following clear text block by a bit operation, a result of which is encrypted, the portable terminal comprising:
a video data repair section that repairs video data which comprises poor video and is subject to repair, by replacing the video data with a portion of video data acquired from an external source,
wherein the video data repair section comprises:
a repair section that saves, without deleting, a last part of the video data to be repaired at the time of repairing the video data by replacing the extracted video data to be repaired with video data for repair; and
a re-encrypting section that re-encrypts only the video data for repair,
wherein the last part of the video data to be repaired is data used for decrypting subsequent video data continuing after the video data to be repaired at the time of playback, and the last part of the video data to be repaired itself is ignored while the playback is performed.
2. The portable terminal according to claim 1 , further comprising:
a repair-target data scanning section that determines a portion in a time range in which the video data requires repair as the video data to be repaired, decodes and scans video data before and after the video data to be repaired per set unit, and re-sets portions in which video is determined not to be distorted even if the video data is replaced and repaired as a start point and an end point of the video data to be repaired.
3. The portable terminal according to claim 1 , further comprising:
a repair data reconstitution section that, when the video data is encoded video data, determines the portion of video data acquired from the external source for repair as the portion of video data, decodes the portion of video data once, extracts video data in the same time range as the video data to be repaired, and uses the video data encrypted in a video format used for the video data to be repaired as the video data for repair in video repair processing.
4. The portable terminal according to claim 1 ,
wherein the video data is encrypted in a CBC (Cipher Block Chaining) mode, and the last part of the video data to be repaired has a fixed length corresponding to a width of the superimposing.
5. A video data repair method of repairing video data which comprises poor video and is subject to repair, by replacing the video data with a portion of video data acquired from an external source, the method comprising and sequentially executing:
extracting the video data to be repaired from video data;
repairing the video data which comprises poor video and is subject to repair, by replacing the video data with the portion of the video data acquired from the external source;
saving, without deleting, a last part of the video data to be repaired at the time of repairing the video data by replacing the extracted video data to be repaired with video data for repair; and
re-encrypting only the video data for repair,
wherein the last part of the video data to be repaired is data used for decrypting subsequent video data continuing after the video data to be repaired at the time of playback, and the last part of the video data to be repaired itself is ignored while the playback is performed.
6. The video data repair method according to claim 5 , further comprising:
determining a portion in a time range in which the video data requires repair as the video data to be repaired and decoding and scanning video data before and after the video data to be repaired per set unit; and
re-setting portions in which video is determined not to be distorted even if the video data is replaced and repaired as a start point and an end point of the video data to be repaired.
7. The video data repair method according to claim 5 , further comprising:
determining the portion of video data acquired from the external source for repair as the portion of video data and decoding the portion of video data once;
extracting video data in the same time range as the video data to be repaired; and
using the video data encrypted in a video format used for the video data to be repaired as the video data for repair in video repair processing.
8. The portable terminal according to claim 5 ,
wherein the video data is encrypted in a CBC (Cipher Block Chaining) mode, and the last part of the video data to be repaired has a fixed length corresponding to a width of the superimposing.