SU1552402A1 - Device for correction of brightness component of television signal - Google Patents

Abstract

The invention relates to television. The purpose of the invention is to increase speed. The device contains multiplexers 1 and 2, a buffer register 3, a computing unit 4, a luminance correction unit 5, a histrogram shaping unit 6, a summing unit 7, and a control unit 8. In operation, two modes are selected depending on the absence or presence of a damping pulse the floor In the first of these modes, a histogram of the velocities of the current TV frame is formed, while the non-linear correction of the incoming digital samples of the luminous component of the TV signal based on the histogram of the velocities of the previous TV frame is carried out at the same time. In the second mode, the computational processing of data is carried out, which from the calculation unit 4 is recorded in the correction unit 5. 1 sludge.

Description

The invention relates to applied television and can be used in devices for processing television (TV) signals in real time.

The purpose of the invention is improving performance.

The drawing shows a structural electrical diagram of the device.

The device comprises a first 1 and a second 2 multiplexers, a buffer register 3, a calculation unit 4, a signal correction block 5, a histogram generating unit 6, a histogram forming unit 6, a summing unit 7 and a control unit 8.

The device works as follows.

At the information input of the device, digital readings of the brightness component of the TV signal are received, while the fourth and fifth inputs of block 8 receive blanking pulses of fields and lines, respectively, and the command code determining the type of non-linear correction of the TV signal is sent to the second control input of block 4. In the operation of the device, two modes are distinguished depending on the absence or presence of a quenching field pulse,

In the 1st mode (there is no blanking field pulse) ', a histogram of the brightness of the current TV frame is generated in block 6, while at the same time in block 5 a nonlinear correction of the incoming digital samples of the brightness component of the TV signal is performed. based on the histogram of the brightnesses of the previous TV frame.

The process of forming a histogram is as follows. Before the beginning of the 1st mode (i.e., during the 2nd mode), block 6 (which is a memory block) is reset to all addresses. The next digital readout of the brightness of the TV signal at the command from the second unit 8 is recorded in the buffer register 3, from where it through the second multiplexer 2 (controlled by the signal from the fifth output of block 8) is supplied to the address input of block 6. The contents of block 6 at the set address are read into the block 7, where one is added to the Read value (if it does not exceed the limit threshold), and by command from block 8, the received value is written to block 6 -Τιο to the same address. Next, the next digital brightness readout is recorded in buffer register 3. In this case, let us skip several adjacent digital brightness samples between the samples recorded in the buffer register 3, according to which the histogram of the current frame is generated, due to the fact that the period of the digital samples may be less than the processing time of one digital sample during the formation of the histogram, t. to. due to strong correlations between adjacent digital samples, the qualitative picture of the obtained histogram does not change with regular skipping of digital samples.

The process of nonlinear correction is as follows. Another digital readout of the brightness of the TV signal through the first multiplexer 1 (controlled by the signal from the fourth output of block 8) is supplied to the address input of block 5 (which is a memory block), from the output of which the adjusted value of the digital brightness readout is read. At the same time, table data conversion is performed.

• In the 2nd mode (there is a quenching field pulse), block 4 (synchronized by block 8) at the first information output generates sequences of address codes, which through the first 1 and second 2 multiplexers (controlled by block 8) go to the address inputs of blocks 5 and 6, respectively Under the control of the signals generated by block 8, at the set addresses, the data from block 6 are read into block 4, where they are processed according to the mode specified by the second control input of block 4, and then block 4 forms on its own torus information output data recorded in the block

Claims (1)

A device for a television signal component comprising a calculation unit, the first information output of which is connected to the combined first inputs of the first and second multiplexers, the outputs of which are connected to the address inputs of the brightness signal correction unit and the histogram generation unit, respectively, while the second input of the first multiplexer is an input for the digital luminance signal of the television image, and the output of the luminance correction block is the output of the corrected digital signal brightly A TV image, characterized in that, in order to improve performance, a control unit, a summing unit and a buffer register are introduced, the information input of which is combined with the second input of the first multiplexer, and the output of the buffer register is connected with the second input of the second multiplexer, while the first, second and third control outputs of the calculation unit are connected respectively to the first, second and third inputs of the control unit, the fourth and fifth inputs of which are inputs for the quenching pulses of 25 fields and rows, respectively, from the first to the ninth outputs of the control unit are connected respectively to the first control input of the calculation unit, the control input of the buffer register, the first control input of the summing unit, the control inputs of the first and second multiplexers, the first and second control inputs of the brightness signal correction unit, and the first and second control inputs of the histogram forming unit, the output of the summing unit being connected to the information input of the histogram forming unit, the output of which connected to the combined information inputs of the data processing unit and the summing unit, the second control input of which is connected to the third control output of the calculation unit, the information input of the brightness signal correction unit is connected to the second information output of the calculation unit, the second control input of which is the input for the correction mode setting code .