HDMI / FC-AV gateway conversion delay measurement system and method

Abstract

The application relates to an HDMI / FC-AV gateway conversion delay measurement system and method, and belongs to the technical field of gateway conversion delay measurement. The system solves the problem that the existing gateway conversion delay measurement relies on professional measurement. The system comprises the following modules: a test frame data generation module which generates corresponding test frame data according to randomly generated test pixel color values; a test pixel pulse generation module which compares the video data signal with the test pixel color value and generates a test pixel pulse signal; an HDMI sending module which converts the test frame data into an HDMI video signal, obtains a reference video data signal through a measured HDMI / FC-AV gateway and an FC-AV link layer; a test point pixel search module which compares the reference video data signal with the test pixel color value and generates a reference test pixel pulse signal; and a conversion delay measurement module which obtains the conversion delay according to the reference test pixel pulse signal and the test pixel pulse signal.

Description

Technical Field

[0001] This invention relates to the field of HDMI / FC-AV gateway conversion delay measurement technology, and in particular to an HDMI / FC-AV gateway conversion delay measurement system and method. Background Technology

[0002] In recent years, systems using the FC-AV protocol to transmit uncompressed high-definition video have become increasingly popular in automotive and airborne applications. The FC-AV protocol, with its high bandwidth, significantly reduces processing latency for uncompressed video transmission. HDMI / FC-AV gateways are devices that convert HDMI video signals to FC-AV signals; their key performance indicators include supported video resolutions and video conversion latency.

[0003] A schematic diagram of the traditional HDMI / FC-AV gateway conversion delay measurement process is shown below. Figure 1 As shown. In Figure 1 In this test, measuring the conversion delay of an HDMI / FC-AV gateway requires cascading FC-AV / HDMI devices to restore the video signal to an HDMI signal. The original HDMI signal and the restored HDMI signal are then connected to an HDMI signal analyzer for measurement. During testing, the accompanying FC-AV / HDMI gateway is typically implemented using an FPGA, which undoubtedly increases the complexity of the test system design and hardware cost. Furthermore, the HDMI signal analyzer used also raises the testing threshold.

[0004] Existing technical solutions test the conversion delay of HDMI / FC-AV gateways through gateway cascading. This involves converting the FC-AV data output from the HDMI / FC-AV gateway back to HDMI data, and then using an HDMI video analyzer to compare the signals from the HDMI signal source with those from the tested FC-AV / HDMI gateway, measuring the delay between the HDMI signals. Based on the principle of symmetry, the delay of a single tested HDMI / FC-AV gateway is half the measured value. This method requires sophisticated testing equipment, necessitating the use of a professional HDMI video analyzer and FC-AV / HDMI gateway, and the conversion delay is measured indirectly rather than directly.

[0005] Therefore, how to reduce the reliance on professional measurement equipment and directly measure the gateway conversion delay using an oscilloscope during the HDMI / FC-AV gateway conversion delay measurement process has become a pressing technical challenge. Summary of the Invention

[0006] Based on the above analysis, the present invention aims to provide an HDMI / FC-AV gateway conversion delay measurement system and method to solve the problem that existing HDMI / FC-AV gateway conversion delay measurement methods are highly dependent on professional measurement equipment.

[0007] On one hand, this invention discloses an HDMI / FC-AV gateway conversion delay measurement system, the system comprising:

[0008] The test frame data generation module generates test frame data containing video data signals for each field based on the row and column positions and color values ​​of the randomly generated test pixels in each field.

[0009] The test pixel pulse generation module compares the video data signal of each field with the color value of the test pixel pixel pixel pixel by pixel to generate the test pixel pulse signal of the corresponding field.

[0010] The HDMI transmitting module continuously receives test frame data from each field and converts it into an HDMI video signal; the HDMI / FC-AV gateway under test receives the HDMI video signal and converts it into an FC-AV signal.

[0011] The FC-AV link layer receives FC-AV signals, performs analysis and detection, and outputs reference video data signals for each field.

[0012] The test point pixel lookup module compares the reference video data signal of each field with the color value of the test pixel pixel pixel in turn, and generates the reference test pixel pulse signal for the corresponding field.

[0013] The conversion delay measurement module measures the conversion delay of the HDMI / FC-AV gateway based on the time interval between the reference test pixel pulse signal and the test pixel pulse signal for each field.

[0014] Based on the above method, the present invention also makes the following improvements:

[0015] Furthermore, the test frame data generation module generates HDMI test frame data for each field based on the row and column positions and color values ​​of randomly generated test pixels for each field, and based on preset video timing parameters.

[0016] The video timing parameters include the number of valid rows per field, the total number of rows per field, the number of valid pixels per row, and the total number of pixels per row.

[0017] Furthermore, the test frame data generation module performs the following:

[0018] The test frame data generation module generates test frame timing based on a dual-counter architecture: the pixel counter and the row counter count in tandem on the rising edge of the clock. When the pixel counter overflows, the row counter increments, and when the row counter overflows, a test is completed.

[0019] At the start of each session, the row number, pixel number, and color value of the test pixel are randomly generated. When the row counter matches the row number of the test pixel and the pixel counter matches the pixel number of the test pixel, the video data signal outputs the color value of the test pixel for this session; otherwise, it outputs all zeros.

[0020] Furthermore, the test pixel pulse generation module performs the following:

[0021] The value of each pixel position in the video data signal of each scene is compared with the color value of the test pixel. If they are equal, the pixel position is the test pixel, and a high-level pulse with a single clock cycle width is output; otherwise, a low-level pulse is output, thus obtaining the test pixel pulse signal.

[0022] Furthermore, the FC-AV link layer includes an FC-AV physical layer and an FC-AV MAC layer.

[0023] Furthermore, the FC-AV physical layer receives the FC-AV signal and performs physical layer parsing to generate a physical layer data valid signal and a physical layer data signal.

[0024] Furthermore, the FC-AV MAC layer receives the valid physical layer data signal and the physical layer data signal output by the FC-AV physical layer, and processes them to obtain reference test frame data containing reference video data signals for each field.

[0025] Furthermore, the conversion delay measurement module performs:

[0026] The time interval between the reference test pixel pulse signal and the test pixel pulse signal for each field is calculated. Then, the time intervals calculated for all fields are processed to measure the HDMI / FC-AV gateway conversion delay.

[0027] Furthermore, the system also includes an oscilloscope; the test pixel pulse generation module sequentially outputs the test pixel pulse signals of each field to one channel of the oscilloscope; the test point pixel search module sequentially outputs the reference test pixel pulse signals of each field to another channel of the oscilloscope.

[0028] At this time, the conversion delay measurement module measures the conversion delay of the HDMI / FC-AV gateway based on the time interval between the reference test pixel pulse signal and the test pixel pulse signal displayed on the oscilloscope for each field.

[0029] On the other hand, the present invention also provides a method for measuring the conversion delay of an HDMI / FC-AV gateway, the method comprising:

[0030] Based on the row and column positions and color values ​​of the randomly generated test pixels in each field, test frame data containing video data signals is generated for the corresponding field.

[0031] The video data signal for each field is compared pixel by pixel with the color value of the test pixel in turn to generate the test pixel pulse signal for the corresponding field.

[0032] It continuously receives test frame data from each field and converts it into HDMI video signals; the HDMI / FC-AV gateway under test receives HDMI video signals and converts them into FC-AV signals.

[0033] The FC-AV link layer receives FC-AV signals, parses and detects them, and outputs reference video data signals for each field;

[0034] The reference video data signal for each field is compared pixel by pixel with the color value of the test pixel in turn to generate the reference test pixel pulse signal for the corresponding field.

[0035] The HDMI / FC-AV gateway conversion delay is measured based on the time interval between the reference test pixel pulse signal and the test pixel pulse signal for each field.

[0036] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0037] The HDMI / FC-AV gateway conversion delay measurement system and method provided by this invention have the following beneficial effects:

[0038] 1. Reduced testing costs and complexity: Without relying on professional HDMI signal analyzers and accompanying FC-AV / HDMI gateways, conversion delay can be directly measured using only an oscilloscope, effectively simplifying the testing system architecture and significantly reducing hardware costs and testing barriers.

[0039] 2. Enable direct measurement: By randomly embedding unique test pixels in the test frame and tracing their complete path from HDMI input to FC-AV output, the time interval between the test pixel pulse signal and the reference test pixel pulse signal is directly measured. This avoids the errors that may be caused by indirect measurement in traditional methods (such as estimating single gateway delay based on the principle of symmetry), thus improving measurement accuracy.

[0040] 3. Enhanced measurement flexibility and adaptability: The test frame data generation module can generate test frames that meet the requirements of different video formats based on preset video timing parameters (such as the number of effective lines in a field and the number of effective pixels in a line). In addition, the position and color value of the test pixels are randomly generated in each field, which can adapt to the conversion delay measurement of HDMI video signals with different resolutions and formats, thus enhancing the versatility of the system.

[0041] 4. Simplified testing process: The entire measurement process is achieved through automated processing of each module, from test frame generation and pulse signal extraction to delay calculation, without the need for complex manual intervention, which simplifies the operation steps and improves testing efficiency.

[0042] 5. Precise Pulse Signal Identification: The test pixel pulse generation module and the test point pixel search module can accurately identify the position of the test pixel by comparing pixel-by-pixel values ​​and generate a high-level pulse with a single clock cycle width, providing a clear and accurate time marker for subsequent time interval measurements.

[0043] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0044] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0045] Figure 1 This is a schematic diagram of the conversion delay measurement process of a traditional HDMI / FC-AV gateway;

[0046] Figure 2 This is a schematic diagram of the HDMI / FC-AV gateway conversion delay measurement system provided in Embodiment 1 of the present invention;

[0047] Figure 3 This is a schematic diagram of the HDMI / FC-AV gateway conversion delay measurement results provided in Embodiment 1 of the present invention;

[0048] Figure 4 This is a flowchart of the HDMI / FC-AV gateway conversion delay measurement method provided in Embodiment 2 of the present invention. Detailed Implementation

[0049] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0050] Specific embodiment 1 of the present invention discloses an HDMI / FC-AV gateway conversion delay measurement system, the structural schematic diagram of which is shown below. Figure 2 As shown. The system includes a test frame data generation module, a test pulse generation module, an HDMI transmission module, an FC-AV physical layer, an FC-AV MAC layer, a test point pixel lookup module, and an oscilloscope.

[0051] (1) Test frame data generation module

[0052] The test frame data generation module generates test frame data for each field based on the row and column positions and color values ​​of the randomly generated test pixels in each field.

[0053] In the specific implementation process, the test frame data generation module sequentially generates HDMI test frame data for each field based on the row and column positions and color values ​​of randomly generated test pixels for each field, and based on preset video timing parameters. In this embodiment, the video timing parameters include the number of valid rows per field (i.e., the number of valid rows per field), the total number of rows per field (i.e., the total number of rows per field), the number of valid pixels per row (i.e., the number of valid pixels per line), and the total number of pixels per row (i.e., the total number of pixels per line). The number of valid rows per field and the number of valid pixels per row are used to specify the resolution of the test frame data and assist in generating valid video data signals; the total number of rows per field and the total number of pixels per row are used by internal counters (pixel counter and line counter) to determine the field boundaries and line boundaries, and generate valid video field signals and valid video line signals.

[0054] Preferably, the test frame data generation module generates the test frame timing based on a dual-counter architecture: the pixel counter (0 ~ total number of pixels in a row - 1) and the line counter (0 ~ total number of lines in a scene - 1) count in tandem on the rising edge of the clock. When the pixel counter overflows, the line counter increments, and when the line counter overflows, a scene is completed. The synchronization signal generation logic is described as follows: Video field valid signal: when the line counter value is less than the number of valid lines in a scene, it is set high to identify the valid display field area; Video line valid signal: when the pixel counter value is less than the number of valid pixels in a row, it is set high to identify the valid display line area; Video data valid signal: the logical AND of the field valid signal and the line valid signal precisely defines the valid pixel window. The video data signal generation process is described as follows: At the beginning of each scene, the row number, pixel number, and color value of the test pixel are randomly generated; when the line counter matches the row number of the test pixel and the pixel counter matches the pixel number of the test pixel, the video data signal outputs the random color value (i.e., the color value of the test pixel in this scene), otherwise it outputs all zeros (black), thereby generating a single-pixel color test point in a pure black background. The final output contains complete test frame data including valid video field signals, valid video line signals, valid video data signals, and valid video data signals.

[0055] The following describes the specific implementation of the test frame data generation module: At the beginning of a test, the test frame data generation module randomly generates the row number, pixel number, and color value of the test pixel. The row number and pixel number together constitute the row and column position of the test pixel. The test frame data generation module drives the pixel counter using a clock signal and resets the internal register using a reset signal. Each time the rising edge of the clock arrives, the pixel counter value increments by 1; when the pixel counter value equals the total number of pixels in a row, the row ends, the pixel counter resets to zero, and the row counter value increments by 1; when the row counter value equals the total number of rows in a test, the test ends, and the row counter resets to zero. If the row counter value is equal to the row number of the test pixel, and the pixel counter value is equal to the pixel number of the test pixel, the video data signal value is the color value of the test pixel; otherwise, the video data signal value is 0. Therefore, the test frame data generated in this embodiment includes a valid video field signal, a valid video line signal, a valid video data signal, and a valid video data signal. When the test frame data generation module enters the next frame (next scene), it will regenerate the row number, pixel number and color value of the test pixels, and then generate the test frame data for the next scene.

[0056] It should be noted that the test frame data generation module in this embodiment supports video generation at different resolutions and frame rates. For example, in 1080P60 frame mode, the reference clock is 148.5 MHz, a frame contains 1125 lines, and a line contains 2200 pixels.

[0057] Subsequently, the test frame data generation module sequentially transmits the video data signals and test pixel color values ​​of each field to the test pixel pulse generation module, continuously transmits the test frame data of each field to the HDMI transmission module, and continuously transmits the test pixel color values ​​of each field to the test point pixel lookup module. It should be noted that in this embodiment, all components of the system use the same clock signal and reset signal to drive their internal logic to work collaboratively, ensuring the timing consistency of data transmission and processing between modules. This synchronous data transmission mechanism ensures that the entire measurement system, from the generation of test frame data to the calculation of the final delay result, is based on a unified time reference and data source, effectively avoiding measurement errors caused by data asynchrony.

[0058] (2) Test pixel pulse generation module

[0059] The test pixel pulse generation module compares the video data signal of each field with the color value of the test pixel pixel pixel pixel by pixel to generate the test pixel pulse signal for the corresponding field.

[0060] Preferably, the test pixel pulse generation module compares the value of each pixel position in the video data signal of each field with the color value of the test pixel. If they are equal, the pixel position is the test pixel, and a high-level pulse with a single clock cycle width is output; otherwise, a low-level pulse is output, thereby obtaining the test pixel pulse signal.

[0061] It should be noted that the test pixel color value is fixed within each frame (i.e., each frame transmission event); the test pixel color value is updated after the next frame (i.e., the next frame). Through this frame-by-frame, pixel-by-pixel comparison and pulse generation mechanism, the test pixel pulse generation module can generate a unique test pixel pulse signal for each frame of test data, precisely corresponding to the position of the test pixel. This pulse signal is then continuously output to a channel of the oscilloscope as a reference signal for the start time of the conversion delay measurement. This design ensures that the appearance of each test pixel can be accurately converted into a clearly distinguishable electrical pulse, providing a precise time marker for subsequent delay measurements.

[0062] (3) HDMI transmission module

[0063] The HDMI transmitting module continuously receives test frame data from each field and converts it into HDMI video signals.

[0064] The HDMI transmitter module can be implemented using mature third-party IP, responsible for converting HDMI test frame data into HDMI video signals, supporting 1080P 60fps video transmission. The HDMI video signal output by the HDMI transmitter module is transmitted to the HDMI / FC-AV gateway under test.

[0065] (4) HDMI / FC-AV gateway under test

[0066] The HDMI / FC-AV gateway under test receives HDMI video signals and converts them into FC-AV signals.

[0067] In the specific implementation process, the HDMI / FC-AV gateway under test recovers information such as resolution and frame rate from the HDMI video signal, generates AV container header and AV container data according to the data format specified by the FC-AV protocol, and sends the AV container header and AV container data to the FC-AV physical layer in the FC-AV signal.

[0068] (5) FC-AV link layer

[0069] The FC-AV link layer receives FC-AV signals, parses and detects them, and outputs reference video data signals for each field to the test point pixel lookup module.

[0070] In this embodiment, the FC-AV link layer includes the FC-AV physical layer and the FC-AV MAC layer.

[0071] The FC-AV physical layer is responsible for receiving FC-AV signals and performing physical layer parsing, generating physical layer valid data signals and physical layer data signals. Specifically, after receiving the FC-AV signal, the FC-AV physical layer performs operations such as serial-to-parallel conversion, 8B / 10B decoding, and synchronization word alignment to restore the signal suitable for fiber optic media transmission into a logical signal. The parsed physical layer data signal contains FC-AV protocol overhead and protocol payload data, and needs to be transmitted to the FC-AV MAC layer to remove the FC-AV protocol overhead; at the same time, the physical layer valid data signal also needs to be transmitted to the FC-AV MAC layer.

[0072] The FC-AV MAC layer receives the physical layer data valid signal and physical layer data signal output from the FC-AV physical layer. After processing, it obtains reference test frame data for each field, including reference video field valid signal, reference video line valid signal, reference video data valid signal, and reference video data signal. In specific implementation, the physical layer data signal identifies FC-AV protocol overhead data, realizes port state machine maintenance, primitive interaction, and video signal recovery, thus obtaining the reference test frame data. Specifically, the FC-AV MAC layer identifies the video resolution information in the FC-AV protocol overhead, stores the protocol payload data in the internal buffer in the order of reception, and then reads the protocol payload data from the buffer in whole line form and carries it to the video data signal; at the same time, the counter generates the reference video field valid signal, reference video line valid signal, and reference video data valid signal during the reading process. The FC-AV MAC layer transmits the reference video data signals for each field to the test point pixel lookup module.

[0073] (7) Test point pixel search module

[0074] The test point pixel lookup module compares the reference video data signal of each field with the color value of the test pixel pixel pixel pixel by pixel to generate the reference test pixel pulse signal for the corresponding field.

[0075] It should be noted that the test point pixel lookup module and the test pixel pulse generation module have corresponding functions. The difference is that the test point pixel lookup module compares the value of each pixel position in the reference video data signal for each field with the test pixel color value, while the test pixel pulse generation module compares the value of each pixel position in the video data signal for each field with the test pixel color value. Therefore, the specific implementation of the test point pixel lookup module will not be elaborated here.

[0076] (8) Conversion delay measurement module

[0077] The conversion delay measurement module measures the conversion delay of the HDMI / FC-AV gateway based on the time interval between the reference test pixel pulse signal and the test pixel pulse signal for each field.

[0078] In the specific implementation process, the time interval between the reference test pixel pulse signal and the test pixel pulse signal for each field is calculated. Then, the time intervals calculated for all fields are processed (such as taking the average value) to measure the HDMI / FC-AV gateway conversion delay.

[0079] Preferably, in this embodiment, the HDMI / FC-AV gateway conversion delay measurement system further includes an oscilloscope. The test pixel pulse generation module sequentially outputs test pixel pulse signals for each field to one channel of the oscilloscope; the test point pixel lookup module sequentially outputs reference test pixel pulse signals for each field to another channel of the oscilloscope. The conversion delay measurement module measures the HDMI / FC-AV gateway conversion delay based on the time interval between the reference test pixel pulse signals for each field and the test pixel pulse signals displayed on the oscilloscope.

[0080] Analysis shows that within the transmission time of a single frame (a frame in a video is also called a "frame"), the color value of the test pixel remains constant. The color values ​​received by the test pixel pulse generation module and the test point pixel lookup module are the same, and each module generates a pulse signal. The time interval between these two pulse signals is the conversion delay of the HDMI / FC-AV gateway. During continuous system operation, a conversion delay can be measured after each frame of video transmission, and this conversion delay can be observed in real time using an oscilloscope. The position of the test pixel will affect the value of the conversion delay, so the selection of test pixels should be random. The system also has an internal counter to record the number of clock cycles between two pulse signals to calculate the conversion delay; it also has a 64-depth delay data buffer to calculate the average delay of 64 data points.

[0081] In engineering terms, video conversion latency is typically in the millisecond range. In a 60fps system, the conversion latency is usually within the transmission time of a single frame. In special cases, when the conversion latency exceeds the transmission time of a single frame, the test pixel pulse generation module uses a new frame in time, and the specific color value of the test pixel is also new; however, the test point pixel lookup module searches for data from an older frame, which does not match the new specific color value of the test pixel, and therefore will not generate a pulse signal, making it impossible to measure the conversion latency.

[0082] Figure 3 This diagram illustrates the measurement results of the HDMI / FC-AV gateway conversion delay provided in an embodiment of the present invention. When video transmission begins and field synchronization is active, the gateway sends AV container header data. When the data validity signal is active, video data conversion begins. The length of the AV container data far exceeds the length of a single FC-AV data frame, so the AV container data is split into many frames. FC-AV frame headers and inter-frame primitives are inserted between each FC-AV data frame, introducing delay. Although a line of video data is split into several frames, these frames are sent before the next active line signal is active. The conversion delay is relatively minimal when the test pixel is encoded in the first FC-AV frame of a line of data, and relatively maximum when the test pixel is encoded in the last FC-AV frame of a line of data. Since the delay introduced by FC-AV data framing is in the microsecond range, much smaller than the buffering time of a single line of video, it still affects the conversion delay of the HDMI / FC-AV gateway. The step of randomly generating test pixels can eliminate randomness in the testing process.

[0083] The inventive point claimed in this technical solution is a pixel-based conversion delay measurement method, which measures the conversion delay by observing the occurrence time of test pixels. By imposing certain conditions, the dependence on professional equipment for delay measurement can be significantly reduced. The conditions imposed by this technical solution are that the conversion delay is less than the transmission time of one frame, and the HDMI signal source must be the specified generated content, achieving the effect of not using an HDMI video analyzer and facilitating observation.

[0084] This technical solution implements an HDMI / FC-AV gateway conversion delay measurement system, which has the following improvements compared to traditional measurement methods:

[0085] Firstly, the system does not rely on professional video analyzers; instead, it uses an oscilloscope to measure conversion delay, reducing the complexity of the accompanying testing equipment.

[0086] Secondly, the conversion delay tested by this system is a direct measurement value, without the need for indirect calculation of the delay through formulas;

[0087] Third, the system has good adaptability. By replacing the HDMI transmitter module, it can test the conversion delay of other video interface gateways. For example, by replacing the HDMI transmitter module with the CAREMALINK transmitter module, the conversion delay of the CAREMALINK / FC-AV gateway can be measured.

[0088] Specific embodiment 2 of the present invention discloses an HDMI / FC-AV gateway conversion delay measurement system, the flowchart of which is as follows: Figure 4 As shown.

[0089] Step S1: Generate test frame data containing video data signals for each field according to the row and column positions and color values ​​of the randomly generated test pixels in each field.

[0090] Step S2: Compare the video data signal of each field with the color value of the test pixel pixel in turn to generate the test pixel pulse signal of the corresponding field.

[0091] Step S3: Continuously receive test frame data from each field and convert it into an HDMI video signal; the HDMI / FC-AV gateway under test receives the HDMI video signal and converts it into an FC-AV signal;

[0092] Step S4: The FC-AV link layer receives the FC-AV signal, parses and detects it, and outputs the reference video data signal for each field;

[0093] Step S5: Compare the reference video data signal and the test pixel color value of each field pixel by pixel to generate the reference test pixel pulse signal for the corresponding field.

[0094] Step S6: Measure the HDMI / FC-AV gateway conversion delay based on the time interval between the reference test pixel pulse signal and the test pixel pulse signal for each field.

[0095] The specific implementation process of this invention can be found in the above method embodiments, and will not be repeated here.

[0096] Since this embodiment is based on the same principle as the above system embodiment, this system also has the corresponding technical effects of the above method embodiment.

[0097] Those skilled in the art will understand that all or part of the processes of the methods described in the above embodiments can be implemented by a computer program instructing related hardware, and the program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a disk, optical disk, read-only memory, or random access memory, etc.

[0098] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A system for measuring the conversion delay of an HDMI / FC-AV gateway, characterized in that, The system includes: The test frame data generation module generates test frame data containing video data signals for each field based on the row and column positions and color values ​​of randomly generated test pixels in each field, and based on preset video timing parameters. In each field, the color value of the test pixel is fixed; when updating to the next field, the color value of the test pixel is updated. The test pixel pulse generation module sequentially compares the video data signal of each field with the test pixel color value pixel by pixel to generate the corresponding test pixel pulse signal. The test pixel pulse generation module performs the following steps: comparing the value of each pixel position in the video data signal of each field with the test pixel color value. If they are equal, the pixel position is the test pixel, and a high-level pulse with a single clock cycle width is output; otherwise, a low-level pulse is output; thus obtaining the test pixel pulse signal. The HDMI transmitting module continuously receives test frame data from each field and converts it into an HDMI video signal; the HDMI / FC-AV gateway under test receives the HDMI video signal and converts it into an FC-AV signal. The FC-AV link layer receives FC-AV signals, performs analysis and detection, and outputs reference video data signals for each field. The test point pixel lookup module compares the reference video data signal of each field with the color value of the test pixel pixel pixel pixel by pixel to generate the reference test pixel pulse signal of the corresponding field. The conversion delay measurement module calculates the time interval between the reference test pixel pulse signal and the test pixel pulse signal for each field; then, it processes the time intervals calculated for all fields to measure the HDMI / FC-AV gateway conversion delay.

2. The HDMI / FC-AV gateway conversion delay measurement system according to claim 1, characterized in that, The video timing parameters include the number of valid rows per field, the total number of rows per field, the number of valid pixels per row, and the total number of pixels per row.

3. The HDMI / FC-AV gateway conversion delay measurement system according to claim 2, characterized in that, The test frame data generation module performs the following: The test frame data generation module generates test frame timing based on a dual-counter architecture: the pixel counter and the row counter count in tandem on the rising edge of the clock. When the pixel counter overflows, the row counter increments, and when the row counter overflows, a test is completed. At the start of each session, the row number, pixel number, and color value of the test pixel are randomly generated. When the row counter matches the row number of the test pixel and the pixel counter matches the pixel number of the test pixel, the video data signal outputs the color value of the test pixel for this session; otherwise, it outputs all zeros.

4. The HDMI / FC-AV gateway conversion delay measurement system according to claim 3, characterized in that, The FC-AV link layer includes the FC-AV physical layer and the FC-AV MAC layer.

5. The HDMI / FC-AV gateway conversion delay measurement system according to claim 4, characterized in that, The FC-AV physical layer receives FC-AV signals and performs physical layer parsing to generate physical layer data valid signals and physical layer data signals.

6. The HDMI / FC-AV gateway conversion delay measurement system according to claim 5, characterized in that, The FC-AV MAC layer receives the valid physical layer data signal and the physical layer data signal output by the FC-AV physical layer, and processes them to obtain reference test frame data containing reference video data signals for each field.

7. The HDMI / FC-AV gateway conversion delay measurement system according to any one of claims 1-6, characterized in that, The system also includes an oscilloscope; the test pixel pulse generation module sequentially outputs the test pixel pulse signal of each field to one channel of the oscilloscope; the test point pixel search module sequentially outputs the reference test pixel pulse signal of each field to another channel of the oscilloscope. At this time, the conversion delay measurement module measures the conversion delay of the HDMI / FC-AV gateway based on the time interval between the reference test pixel pulse signal and the test pixel pulse signal displayed on the oscilloscope for each field.

8. A method for measuring the conversion delay of an HDMI / FC-AV gateway, characterized in that, The method is implemented based on the system according to any one of claims 1-7; the method includes: Based on the row and column positions and color values ​​of randomly generated test pixels in each scene, and based on preset video timing parameters, test frame data containing video data signals for the corresponding scene is generated sequentially; in each scene, the color value of the test pixel is fixed; when updating to the next scene, the color value of the test pixel is updated; The video data signal of each field is compared pixel by pixel with the color value of the test pixel in turn to generate the test pixel pulse signal of the corresponding field. Specifically, the value of each pixel position in the video data signal of each field is compared with the color value of the test pixel. If they are equal, the pixel position is the test pixel and a high-level pulse with a single clock cycle width is output; otherwise, a low-level pulse is output; thus, the test pixel pulse signal is obtained. It continuously receives test frame data from each field and converts it into HDMI video signals; the HDMI / FC-AV gateway under test receives HDMI video signals and converts them into FC-AV signals. The FC-AV link layer receives FC-AV signals, parses and detects them, and outputs reference video data signals for each field; The reference video data signal for each field is compared pixel by pixel with the color value of the test pixel in turn to generate the reference test pixel pulse signal for the corresponding field. The time interval between the reference test pixel pulse signal and the test pixel pulse signal for each field is calculated. Then, the time intervals calculated for all fields are processed to measure the HDMI / FC-AV gateway conversion delay.

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