摘要:
Digital data units representative of analog audio signal are constructed into a data unit sequence with an error detection code being added to each of the data units for detecting coding errors within the data unit, and data synchronizing signals are inserted one for every predetermined interval of the data unit sequence to constitute a PCM data sequence, which is recorded and reproduced. The number of times of coding errors detected within the data unit by the error detection code during the time period between one data synchronizing signal and the next following data synchronizing signal is monitored and when the number exceeds a first predetermined count, the audio output is muted, and when the number decreases below a second predetermined count which is much smaller than the first predetermined count, the muting mode of the audio output is released to prevent the noise output.
摘要:
A PCM signal processing apparatus for recording or reproducing a PCM signal. The PCM signal reproducing apparatus of the invention is constituted by: a data addition circuit for receiving a first signal composed of n bits per word (n being an integer) and a second signal composed of n' bits per word (n' being an integer) as mode inputs different from each other, and for adding fixed data of (n-n') bits to every word of the second signal to thereby generate a third signal; a first switch device for receiving the first and third signals and for selectively outputting one of the first and third signals; a symbol generation circuit for converting every word of the output of the first switch device into symbol data of m.times.l bits (n>l); a signal processing circuit for performing at least interleave processing, error correction code generating processing, and addition of a synchronizing signal, on the output of the symbol generation circuit, to thereby generate a first data frame; a data deletion circuit for deleting the fixed data from the first data frame of the signal processing circuit to thereby generate a second data frame; and a second switch devices for receiving the first data frame from the signal processing circuit and the second data frame from the data deletion circuit.
摘要:
A digital-to-analog converter device for PCM signals at different sampling frequencies comprises a signal converter which expands the frequency distance between a PCM signal band and a side band by converting the sampling frequencies associated with the PCM signals to be reproduced into higher frequencies. With this signal converter, a single low-pass filter can be simplified, having a gradual ramp cut-off characteristic for removal of the side band wherein a pass band cut-off frequency and a stop band cut-off frequency can be adapted for low pass filtering of the PCM signals at different sampling frequencies.
摘要:
In a pulse width detector circuit, a high-level pulse width and a low-level pulse width of a digital signal derived by slicing an analog signal reproduced from a disc at a predetermined level are independently measured and maximum or minimum values thereof in a predetermined time interval are stored, and an average value, sum or difference of the maximum or minimum high-level pulse width and the maximum or minimum low-level pulse width is calculated to detect a correct pulse width of original data recorded on the disc.
摘要:
A PCM recorder includes an A/D converter for converting an analog signal to a digital signal, an interleave unit for pseudo-randomizing the digital signal by rearranging on time base, a video tape recorder for recording the pseudo-randomized digital signal on a video tape, and a control circuit for controlling the interleave unit and the video tape recorder in a synchronized manner. Since the video tape recorder and the interleave unit are synchronously controlled, discontinuity of data at the joint of recording can be prevented even if recording is paused and restarted.
摘要:
A solid state imaging device detects the period of energy variation of discharge type illumination, and sets a total exposure time to match the detected period. The total exposure time is divided into alternating valid and invalid exposure times by a division ratio to make the sum of the valid exposure times equal to an actual exposure time corresponding to an actual speed of an electronic shutter. Charges accumulated in a CMOS sensor during the valid exposure times are stored in a floating diffusion, whereas charges accumulated during the invalid exposure times are drained. At the end of the total exposure time, the charges stored during the valid exposure times are converted to an electrical signal which is output to a signal processing circuit. This device can correct variation of output signals which corresponds to the illumination energy variation when the shutter is operated for imaging under high luminance illumination.
摘要:
Adjacent pixels in a pixel circuit of an imaging device use a primary capacitance, an amplifying transistor, a reset switch and a selection switch in common. Each pixel has a photodiode and a transfer switch having first and second gates provided on the photodiode side and the primary capacitance side, respectively. In a pixel downsampling read mode, the first and second gate voltages of each pixel to be discarded are brought to high level, and thereafter the first and second gate voltages of each pixel to be read are brought to high level, to transfer charge generated in the photodiode of the pixel to be read to the primary capacitance and the photodiode in each pixel to be discarded. This enables reduction of the potential of the primary capacitance, and hence reduction of the pixel sensitivity than using only the primary capacitance to store charge transferred from the transfer switch.
摘要:
An information storage apparatus recognizes a traffic sign on a road expressed by a road surface image, and stores recognized traffic sign in association with its position information in a hard disk drive. By recognizing and storing information on the traffic sign in combination with the position information for the sake of traffic safety, information coverage in terms of traffic safety is updated to the most up-to-date condition for roads in the entire country.
摘要:
The cement admixture of the present invention can provide viscosity decreasing ability as well as a high dispersing ability and slump loss preventing ability even in a high water reducing ratio range. The above-mentioned cement admixture comprises three components of a copolymer (A) containing a constituent unit (I) derived from the unsaturated (poly)alkylene glycol ether monomer (a) and a constituent unit (II) derived from a maleic acid monomer (b), a specific unsaturated (poly)alkylene glycol ether monomer (a) and a non-polymerizable (poly)alkylene glycol (B) having no alkenyl group.
摘要:
A cement admixture object of the present invention can make slump-retaining ability excellent to retain fluidity and, at the same time, can realize a viscosity of cement compositions so that work becomes easy at a field handling them, can make the state of a cement composition better. The present invention relates to a cement admixture which comprises a polycarboxylic acid copolymer having a polyalkylene glycol side chain, said polycarboxylic acid copolymer being constituted of two or more species of copolymers with different acid values, and at least one of said two or more species of copolymers with different acid values having an oxyalkylene group containing 3 or more carbon atoms.