Patent ID: 7321721

Claim:
A hard disk apparatus comprising: recording means of recording AV data onto a hard disk; and stream controlling means, coupled to the recording means, of processing the signal of AV data transmitted from an interface or the signal of AV data transmitted to the interface; wherein, the hard disk apparatus records and/or reproduces the AV data, and wherein, a size of a disk access unit serving as a minimum continuous unit in the access to the hard disk is set to be equal to or greater than a size obtained by the following Formula (1): Rch = D T , where ( Formula ⁢ ⁢ 1 ) Rch indicates a transfer rate per channel, D indicates the size of the disk access unit to be determined, T indicates a process time necessary for recording or reproducing the data of size D, and T is set to be a value equal to the greater value of T 1 obtained from the following Formula (2) and T 2 obtained from the following Formula (3): T1 = D Ri × C + W × C + S st × C , where ( Formula ⁢ ⁢ 2 ) T 1 indicates a process time necessary for recording or reproducing the data of transfer size D to or from the inner circumference of the magnetic disk, Ri indicates a rate of recording to or reproducing from the inner circumference of the magnetic disk, C indicates a number of channels in multi-channel processing, Sst indicates a time necessary for a settling action, and W indicates a time of rotation waiting, T2 = ( C ÷ 2 ) ⁢ ( D Ri + D Ro ) + ( C ⁢ %2 ) ⁢ D Ri + W × C + ( S fsk + S st ) × C , where ( Formula ⁢ ⁢ 3 ) T 2 indicates a process time necessary for recording or reproducing the data of transfer size D to or from both the inner circumference and the outer circumference of the magnetic disks, Ro indicates a rate of recording to or reproducing from the outer circumference of the magnetic disk, and Sfsk indicates a time necessary for a full stroke.