Image data communication transmission methods

Abstract

This invention provides a communication transmission method for image data, comprising: an image sensor communicating with an image processing module using a high-speed serial communication protocol; image data from the image sensor being transmitted via data packets, each data packet including two identical start characters and two identical end characters; and the same data packet being transmitted separately on several transmission channels. The start and end characters of the packet indicate the packet boundary; any bit errors at the start or end of the packet will cause packet boundary detection failure, resulting in image corruption. Using two identical start and end characters makes packet boundary detection reliable. Placing one set of start and end characters on different transmission channels compared to another set provides noise immunity against transient interference that causes consecutive multi-bit errors on a particular channel.

Claims

1. A method for transmitting image data via communication, characterized in that it comprises: The image sensor communicates with the image processing module using a high-speed serial communication protocol. Image data from the image sensor is transmitted via data packets, each packet containing two identical start characters and two identical end characters. The same data packet is transmitted on several transmission channels. One start character and one end character from the data packet are sent on one transmission channel; another start character and another end character are sent on a different transmission channel. The power cycle of the communication link between the image sensor and the image processing module includes: sleep state, ready state, training state, transmitting state, and exit state. When no image data needs to be transmitted, the link is in the sleep state. One or both ends of the link are simultaneously in a low-power mode or idle mode. In the sleep state, the power consumption of the communication interface is close to zero. When image data needs to be transmitted, the link is in the transmitting state. From the sleep state to the transmit state, the link goes through the preparation state and the training state; the preparation state is to establish an electrical state, and the training state is for the receiver to automatically perform equalization and adaptation training on channel loss and phase adaptation training on the transmitter data; from the transmit state to the sleep state, the transmitter sends a special code in the exit state to notify the receiver of the state change before entering the sleep state.

2. The method for transmitting image data as described in claim 1, wherein the data packet further includes, after the two identical packet start characters: Two identical packet headers, each header including: image stream number, payload length, and redundancy check code.

3. The image data communication transmission method as described in claim 2, wherein the packet header specifically includes an 8-bit image stream number, a 32-bit payload length, and an 8-bit redundancy check code.

4. The image data communication transmission method as described in claim 1, wherein each data packet contains one line of image data; if there is a blank time between different data packets, it is filled with a padding character; the blank is filled in the transmission channel with the padding character so that the packet start character and the packet end character are always on channel 0 and channel 1; the padding character is (<D0.0>, <D0.0>).

5. The image data communication transmission method as described in claim 1, wherein the data stream of the image data transmission further includes a control packet, the control packet identifying the start and end of the data packet, identifying any one of the RAW format, RGB format or YUV format of the image data corresponding to the image stream number, and identifying the frame count.

6. The image data communication transmission method as described in claim 5, wherein the control packet also includes two identical packet start characters and two identical packet end characters; one packet start character and one packet end character of the control packet are sent in a first transmission channel; another packet start character and another packet end character of the control packet are sent in a second transmission channel; the packet start character is (<K28.5>, <D0.0>), and the packet end character is (<K28.5>, <D1.0>).

7. The method for transmitting image data as described in claim 5, wherein the control packet further comprises: Start of Frame Control (SFC) packet and End of Frame Control (ESC) packet; The frame start control packet, the frame end control packet, the image line data packet, and the embedded line data packet together transmit a complete image frame.

8. The image data communication transmission method as described in claim 1, wherein the active mode is defined as the image sensor actively controlling the training duration and entering the transmission state in the training state; the passive mode is defined as the image sensor continuously outputting training data in the training state, and the image processing module notifying the image sensor to stop outputting training data and instead output image data via I2C command, SPI command, or GPIO state; the image sensor always acts as a device, and the image processing module always acts as a host; when data transmission is required in the active mode or the passive mode, the device initiates a state transition, entering the preparation state from the sleep state, and then the training state.

9. The image data communication transmission method as described in claim 8, wherein there are two ways to end the training state and start the transmission state; First: In the passive mode, the host notifies the device that training is complete via an I2C command, an SPI command, or a GPIO status; Second: In the active mode, the device's counter reaches a predetermined training time.

10. The image data communication transmission method as described in claim 8, wherein from the perspective of the device, the passive mode is that the device is controlled by the host to switch from the training state to the transmission state; the active mode is that the device determines whether to switch from the training state to the transmission state by its own timer; in both the passive mode and the active mode, the host initiates a set external trigger signal xTrig to request the device to start from the sleep state, pass through the training state, and enter the transmission state; or the host causes the device to start from the sleep state and enter the transmission state through an I2C command or an SPI command.

11. A method for transmitting image data as claimed in claim 1, wherein the image data is scrambled and encoded before being transmitted to a differential channel, comprising: The image data is distributed sequentially to N channels in 16-bit units using a data distributor, with each channel receiving 16 bits of the image data; the N channels simultaneously perform the data scrambling and encoding operations in parallel.

12. The communication transmission method for image data as described in claim 11, wherein the channel performs the data scrambling and encoding operations, specifically including: The 16-bit data from the image data obtained by the channel allocation is XORed with a pseudo-random sequence generated by a pseudo-random binary sequence generator and then input into an 8b / 10b encoder to obtain a 20-bit data character. The K code generator generates a K character, and the selector determines whether the data stream of the image data transmission contains a K character or a D character. The selector outputs 10 bits of parallel bus data and converts the parallel bus data into serial data for bit-by-bit transmission.

13. The image data communication transmission method as described in claim 1, wherein the image processing module includes any one of FPGA, DSP and ISP.

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