摘要:
A watermark embedding method based on DCT subband image characters is disclosed. An original image is converted into a frequency image using a discrete cosine transformation. The watermark information is then embedded into a specific embedding block in each macro-block of the frequency image. The method has the following advantages: (1) the image embedded by watermark is resistant from distortion and damages from compressions; (2) the watermark image can be extracted without employing the original image; and (3) the quality of the image embedded with the watermark image can remain intact.
摘要:
A watermark embedding method based on DCT subband image characters is disclosed. An original image is converted into a frequency image using a discrete cosine transformation. The watermark information is then embedded into a specific embedding block in each macro-block of the frequency image. The method has the following advantages: (1) the image embedded by watermark is resistant from distortion and damages from compressions; (2) the watermark image can be extracted without employing the original image; and (3) the quality of the image embedded with the watermark image can remain intact.
摘要:
A method controls the access times of an optical disc end discs of the same. The method includes the following steps. First, an optical disc drive obtains the addresses of a life flag and a medium key block (MKB) by reading a private flag of an optical disc. The life flag and the MKB are used to control the access times of the optical disc. After confirming the addresses of the life flag and the MKB, the optical disc drive obtains an optical power signal to determine the power that should be used to read the MKB. When the optical disc drive uses the appropriate reading power to access the MKB, the recognizable number of access times in the 4KB data is reduced, and the medium key signal is extracted to be confirmed if it is recognizable to restate the main data.
摘要:
The specification disclosed a method that controls the access times of an optical disc and discs of the same. The method includes the following steps. First, an optical disc drive obtains the addresses of a life flag and a medium key block (MKB) by reading a private flag of an optical disc. The life flag and the MKB are used to control the access times of the optical disc. After confirming the addresses of the life flag and the MKB, the optical disc drive obtains an optical power signal to determine the power that should be used to read the MKB. When the optical disc drive uses the appropriate reading power to access the MKB, the recognizable number of access times in the MKB data is reduced, and the medium key signal is extracted to be confirmed if it is recognizable to restore the main data.
摘要:
This specification disclosed a method of determining the disc type for a disc burner to determine the type of an unfinalized disc. By checking the special bit data in the first and second tracks, the discs can be classified into different types. This avoids the trouble of manually keeping track of the type of each disc.
摘要:
This specification disclosed a method of determining the disc type for a disc burner to determine the type of an unfinalized disc. By checking the special bit data in the first and second tracks, the discs can be classified into different types. This avoids the trouble of manually keeping track of the type of each disc.
摘要:
A disc burner and its control method applicable to high speed disc burner, to solve disc burning failure problem due to burning speed exceeding encoding speed. A buffer is inserted to store the encoded data in groups, and these data groups are used in sequence for disc burning purpose. Therefore, the waiting time of the writing laser is spread out and does not exceed the threshold waiting time, and there is no disc burning failure problem.
摘要:
A disc burner and its control method applicable to high speed disc burner, to solve disc burning failure problem due to burning speed exceeding encoding speed. A buffer is inserted to store the encoded data in groups, and these data groups are used in sequence for disc burning purpose. Therefore, the waiting time of the writing laser is spread out and does not exceed the threshold waiting time, and there is no disc burning failure problem.
摘要:
A rewritable DVD-RAM disc. By changing the location or dimension of the lead-out area of the DVD-RAM disc, the data area of the disc can be enlarged. The enlarged area of the disc can be flexibly applied to the user area, the main spare area, or the backup spare area.
摘要:
A method is proposed for managing defect areas on an erasable optical disc in a dynamic manner. By this method, a main spare area including a plurality of logical blocks is used to provide substitution logic blocks for any bad logical blocks in the user read/write area; and when all the logical blocks in the main spare area are used up, a supplementary spare area is defined from a continuous unused storage area in the user read/write area; and further, when all the logical blocks in this supplementary spare area are used up, an additional supplementary spare area is defined from another continuous unused storage area in the user read/write area; and so forth. The method allows the use of a comprehensive set of commands and data message for the communication between the file system and the optical drive when performing this management method. This method allows the optical drive to move over a shorter distance from a bad logical block to the substitution logic block so that access time to the optical disc can be enhanced. Moreover, this method allows all the bad logical blocks to have substitutions as long as the unused storage space in the formatted area is sufficient, so that this method can offer a much longer time of service than the prior art.