TWI497981B - Method and apparatus for testing video signals - Google Patents

Description

Image signal test method and device

The present invention relates to an image signal test method and apparatus, and more particularly to an image signal test method and test apparatus for evaluating an image signal of an external device under test.

In the design of audio-visual electronic products, the image performance capability is increasingly emphasized. The image function depends on high resolution, high update rate, and higher quality chromatic aberration. Therefore, the image testing of the product needs to integrate multiple functions and shorten the test time to reduce the cost.

When the video signal is processed or converted by a specific device or circuit, the problem of quality degradation and video signal distortion often occurs, and the problem lies in the signal processing method of the relevant processing circuit.

Therefore, video signal evaluation is a very important requirement for the evaluation of a device. Traditionally, some mathematical algorithms have been used to analyze the video signals processed by the circuit, and the original signals are compared according to certain standards. The reference value is the signal-to-noise ratio (SNR) of the video, which is used as the basis for judging whether the signal is affected or distorted.

Another conventional technique is to evaluate a moving image by judging the frame rate of each frame in the image signal, and mainly judges the image quality based on the change of the preceding and succeeding frames in the moving image.

In the current technology, it is particularly possible to directly output the actual image through the display, and the operator can see whether the picture is normal by the human eye, but this method requires not only a large amount of manpower, but also the operator has to undergo long training to make a correct judgment, but cannot Avoid people being tired or inexperienced due to prolonged operation A situation in which a judgment error occurs. You can also purchase a professional image tester for testing, but there are still problems that cannot be reduced.

The invention provides an image signal testing method and a device for performing the method. According to one of the objects of the present invention, the image signal testing method mainly uses a testing device to receive an image signal outputted from a device under test as an object of testing, and is compared. Refer to the signal to make a judgment on the quality of the signal.

According to an embodiment, the image signal test method is performed by an image signal test device connected to the device under test, and the image signal test device is provided with a plurality of ports for receiving image signals. Preferably, the port supports a variety of different image signals. The format, the test device receives the image signal output by the at least one device to be tested, and the output signal is preferably one or more test patterns including multiple colors that are continuously output.

Then, the image signal testing device determines the signal format of the image signal output by the at least one device to be tested, and the attributes of the device to be tested, wherein each signal format conforms to an image interface specification, such as a multimedia interface called high-definition quality ( High Definition Multimedia Interface (HDMI) image connection interface, or general composite AV connector, does not exclude other analog or digital image interfaces, such as a component video connector, independent video Terminal (S-video), S/PDIF digital transmission interface or an analog audio terminal.

Then, the image signal test device captures the image signal output by the at least one device to be tested, and performs signal conversion, signal sampling and the like, and compares the sampled signal with the reference value to determine the signal quality. According to an embodiment, The values sampled are the color values in the image signal, such as the pixel values of red, green, and blue, or the brightness contained in the color difference terminals, and the difference between the brightness and red, blue, and the like.

The device to be tested is an electronic device having a plurality of image signals, such as a video conversion and/or playback device, which can simultaneously connect to an input interface of the image signal testing device.

According to an embodiment of the image signal testing device for performing the image signal testing method of the present invention, the device includes an input interface unit connected to one or more devices to be tested, and one or more images outputted by one or more devices to be tested. Signal extraction unit of signal, sampling unit for performing signal sampling to obtain color value, storage unit for temporarily storing color value, calculation unit for obtaining color value by storage unit to perform color evaluation, and output interface for outputting comparison result unit.

The input interface unit can be provided with a plurality of connection ports conforming to various image interface specifications, and the image signal test device is connected to support a device for testing with various interface specifications, such as a video conversion or/and playback device.

In order to provide an effective and low-cost image signal test solution, the present invention provides a video signal test method and device capable of determining image quality according to a fixed image output by the device under test, and the technical test device can utilize a general function computer system. The computer system carries an image capture card taken from the image signal generated by the device under test, performs signal conversion, obtains a test signal, and determines the image quality according to the reference value.

One of the embodiments may refer to one of the schematic diagrams of the embodiment of the image signal testing device of the present invention shown in FIG.

An image signal testing device 10 receives a test signal from the image signal source 11. The source of the test signal can be provided by the image signal testing device 10 itself. Therefore, the image signal testing device 10 outputs the master to the device under test (the source of the image signal 11). The signal is used to effectively judge the quality of the signal input after being processed by the device under test. The test signal is especially an image signal carrying some test patterns. The image signal testing device 10 is configured to perform the image signal testing. The circuit mainly composed of the hardware includes a signal capturing unit 101 that extracts the signal generated by the signal source 11. According to one of the embodiments, the signal capturing unit 101 Mainly to obtain image signals, such as capturing consecutive digital still frames from analog video signals or digital video streams. For example, if the image signal source 11 is a set-top box, the generated signal is usually an analog signal for television broadcast, so the signal capture unit 101 performs analog-to-digital conversion, the aforementioned frame. It will be captured in the form of a digital frame, and then sampled by the electrically connected/coupled sampling unit 102 to sample the digital signal, such as the color related data contained in the signal.

For example, the color-related data sampled here has color modes such as red (R), green (G), and blue (B) using an RGB model, and the color value of each pixel is composed of R, G, and B components. The composition, for example, each component is assigned an intensity value in the range of 0 to 255. At this time, the pure red R value is 255, and the other components G value and B value are 0; if it is black, the R, G, and B components are three components. The values are all 0; if it is pure white, the R, G, and B components are all 255, and so on. Therefore, the image composed of the pixels of the R, G, and B components can be mixed and displayed in a different ratio to display a true color.

In addition to the color representation of the aforementioned RGB model, embodiments of the present invention do not exclude application to other color models such as HLS (hue, brightness, and Saturation) and the four-quadruple mode (CMYK).

After that, the obtained color-related data will be stored (or temporarily stored) in a storage unit 103, and then processed by the calculation unit 104, and the actual color values obtained from the storage unit 103 are compared with a preset reference value. Through the comparison and data processing, a result of the evaluation is obtained. The result output unit 105 outputs the content including using the report, or analyzing the evaluation, or displaying the test result such as whether or not the test is passed. The purpose of the embodiment of the present invention is to obtain the difference between the actual color value of the input image signal and the preset reference value to make a good or bad or level evaluation, thereby judging the quality of the signal after the image digitization and the color value sampling. It can reflect the ability of the device under test to process image signals.

2 is a schematic view showing an embodiment of another image signal testing device of the present invention. In this embodiment, an image signal testing device 20 is also provided. The device to be tested is disclosed as a signal conversion device 200, such as a set-top box. Upon input of the test signal 21 to the signal conversion device 200, the signal generated by the signal conversion device 200 is transmitted to the image signal testing device 20.

In this example, the image signal testing device 20 includes a hardware circuit and a software module that implement various functions by hardware or software, and the image signal test is performed through the circuit or the software unit, such as electrically connecting to each other or The input interface unit 201, the signal processing unit 23 (including the signal acquisition module 202, the signal conversion module 203 and the signal sampling module 204), the statistics unit 205, the comparison unit 206, the result output unit 207, and the output interface The unit 208 and the storage unit 209 storing the threshold value 291, the program code 292 of the device operating program and the calculation program, the test signal 293, and the reference value 294 for evaluating the signal quality.

According to an embodiment, the image signal testing device 20 is provided with an input interface unit 201 for connecting one or more external devices to be tested (such as the signal conversion device 200). The input interface unit 201 can be provided with one or more to be connected. The properties of the device and the circuit that determines the format of the output image signal. In order to meet the requirement that the test device 20 can support multiple input signal formats, the input interface unit 201 can be provided with multiple ports that conform to various image interface specifications.

The various signal formats should correspond to the specifications of an image interface, such as the high definition multimedia interface (HDMI) image connection interface, the composite AV connector, and the component video connector. , independent video terminal (S-video), S/PDIF digital transmission interface or an analog audio terminal (analog audio).

Then, a signal processing unit 23 is electrically connected to the input interface unit 201, and includes various functional modules implemented by hardware circuits or software and firmware. The signal capture module 202 and signal conversion are as shown. Module 203 and signal sampling module 204. One of the main tasks is to convert the received signal into a signal for comparison, such as performing a necessary analog signal to digital signal, through the signal capture module 202 receiving image signals of various specifications. According to one embodiment, since the image signal usually carries a large amount of data information, the test device can temporarily store the signal in the buffer when the signal acquisition module 202 obtains the signal, and the signal can be retrieved by the signal. The conversion module 203 performs signal conversion, and converts the captured image signal into a signal that can be compared by a subsequent operation, such as a digital signal, and then processed by a subsequent circuit, and the input interface unit 201 and the signal processing unit 23 are implemented. Like an image capture card, or can include both signal capture and transfer Switch or / and sample the circuit.

According to the embodiment of the image signal test of the present invention, the converted signal will be subjected to sampling after sampling, for example, by the signal sampling module 204 in the signal processing function in the figure, thereby reducing data processing. And the color information contained in the signal can be obtained by the embodiment. The embodiment provides a threshold value 291, and the threshold value 291 is recorded in the storage unit 209 of the device 20 as a basis for sampling acquisition as a basis for image quality evaluation. If the sampled amount is lower than the threshold value 291, if it is lower than the threshold value 291, the sampled image should be resampled or re-inputted by the device under test. The invention performs quality assessment based on color information in the image signal. Accordingly, the signal sampling module 204 receives the signal processed by the signal conversion module 203, performs sampling, and obtains the color value of the signal.

The storage unit 209 is a memory of the image signal testing device 20, and is electrically connected to the signal processing unit 23 and the subsequent calculated related circuit. In addition to storing the threshold value 291 and the reference value 294, the storage unit 209 can be used to store the image signal testing device. The operating program at the time of operation, the program code 292 for executing the test, and the like, and because the image signal testing device 20 also provides a pattern or value for testing, the storage unit 209 is also used to store the provision in the device 20. Test signal 293.

According to one of the embodiments, the image signal for testing, such as a continuous output test pattern, can be referred to the illustrations shown in FIGS. 5A to 5G of the present invention. During the sampling process, the color values of multiple pixels (for example, 10) of each color of the test image are obtained, and various statistical values are taken as the basis for the quality test.

In the core of the calculation, a statistical unit 205 is used to perform statistical calculation on the obtained color data. For example, the embodiment may calculate the average value and the standard deviation, and then add or subtract the range of at least 2 standard deviations by the arithmetic mean. As a condition for testing. There may also be a memory for storing the calculated data, such as a storage unit (not shown).

Then, the comparison unit 206 takes over the comparison unit 206 for comparing the color statistics obtained by the foregoing statistics unit 205 with the reference value 294, such as taking the statistically calculated data from the storage unit, and comparing the preset comparison data. As the reference value 294, as a basis for color evaluation, the result of the evaluation after the result output unit 207 is finally obtained is output by the output interface unit 208, for example, as a report output 22.

According to the technical purpose of the present invention, one or more image signals output by one or more devices to be tested can be simultaneously tested, in particular, one or more test patterns including multiple colors continuously outputted, and the image signal test of the present invention is displayed according to FIG. The device performs a connection diagram of the test. In this example, the image signal testing device 30 can simultaneously connect a plurality of ports of the device to be tested 300. When a test signal 31 is first input into the device to be tested 300, the test process can be sequentially obtained from each port. The input signal (converted from test signal 31), or the signal of each connection port at a time, the resulting test result 32 will be evaluated according to the signal quality of various ports.

The device to be tested 300 can be a video conversion device for converting an input signal into an image signal. The device under test 300 can be an electronic device having a plurality of image signals, and the plurality of image signals of the device to be tested 300 can be simultaneously connected. The input interface unit of the image signal testing device 30 is provided with a plurality of ports (not shown in this example) that conform to various image interface specifications. In this example, the image signal testing device 30 can simultaneously connect a plurality of ports supported by the device to be tested 300, such as the first port 301 shown in the figure, and connect the image signal testing device 30 with the first connection 302; The connection port 303 is connected to the image signal testing device 30 by the second connection 304; the third connection The interface 305 is connected to the image signal testing device 30 by a third connection 306; and is connected to the image signal testing device 30 by a fourth connection 307 with a fourth connection 308.

The test signal calculation device 30 is shown with a test calculation core 309. After the test signals are obtained through the ports, the calculation is performed, and finally, the output is output via the output interface unit 310. The necessary circuit unit for calculating the evaluation is preferably referred to FIG. .

The image signal testing device described in the disclosure of the present invention can obtain consecutive digital still frames from analog video signals or digital video streams, and each frame can be captured in digital form, and the generated digital signals are directly or through After compression, display, store or transfer to other devices, and the present invention is used to obtain color values after sampling as the purpose of image evaluation.

4 is a schematic diagram showing the connection of the test using the image signal test device of the present invention. The image shows an image signal test device 40, which receives image signals output from a video conversion device (such as a set-top box) 41, and various image signals. The first image 埠 411 is shown to transmit a high definition multimedia interface (HDMI) image signal.

The image signal 埠, as shown in the second image 埠 412, transmits an image signal with a component video connector. It is worth mentioning that the brightness in the analog video (Y component, carrying brightness or luminance) ), and the difference between the blue and the brightness contained in P _B and the difference between the red and the brightness contained in P _R .

The image signal 埠 other, such as the third image 埠 413, transmits an independent video terminal (S-video), wherein the “S” is an abbreviation of Separate, which can divide the video data into two separate signals (brightness and color). Degree) The analog signal sent.

In contrast, another image signal, such as the fourth image 埠 414, is different from the S-video to separate the image data, and the fourth image 414 is a composite AV connector that is packaged and transmits the signal as a whole. Video signal transmission.

Another example is the fifth image 埠415, thereby transmitting a signal carried by the S/PDIF digital transmission interface. It is worth mentioning that the S/PDIF (Sony/Philips Digital Interface Format) is a digital transmission interface, generally using optical fibers and Coaxial cable output, commonly used in digital cinema systems (DTS, Digital Theater Systems) and Dolby Digital video.

The image signal 埠 also includes a sixth image 埠 416, which represents an analog audio terminal.

The foregoing various image signals are connected to the signal input interface unit 401 of the image signal testing device 40, and are sequentially or simultaneously converted and sampled by the signal, and enter the illustrated test calculation core 403. After calculation and comparison, the borrowing may be performed. This evaluates the quality of the signals contained in each signal, and finally outputs the test result 42 by the output interface unit 405.

According to the embodiment of the present disclosure, the image signal testing device forms an image signal testing system, wherein at least one image capturing card can be loaded in a computer system, and at least one image playing device to be tested is connected, and image capturing is performed. The card is provided with a connection port corresponding to various image frames supported by the device under test, including various connection methods of wired or wireless. The image capture card can be an interface card supporting a specific interface, and is connected to a PCI (Peripheral Component Interconnect), PCI-E (PCI Express) or USB interface on a computer system device.

Through this test system, the computer system can generate transmission test signals by itself. The various test patterns shown in FIG. 5A to FIG. 5G are transmitted to the device under test via a transmission device or a transmission device, such as a universal wired transmission port, and are not excluded from being transmitted by means of Ethernet, or may be wirelessly transmitted. Means (such as Wi-Fi or Bluetooth) transmission. Then, the test device receives the test pattern outputted again from the device under test through the image input interface. Therefore, the image testing method carried in the computer system can conveniently compare the input to the device under test and the transmitted image signal to confirm the quality of the image signal broadcasted by the device under test.

5A through 5G are schematic views showing an embodiment of a test pattern utilized in the present invention.

As can be seen from the examples of the test patterns, each test pattern is provided with a plurality of monochromatic color patches, such as yellow (Y), red (R), blue (B), green (G), orange (O), purple. (V) or the like, but the actual implementation is not limited to the patterns of various shapes and color blocks shown in the drawings. It is worth mentioning that the test pattern is usually preloaded in the memory in the device under test and continuously output during the test, but it is not excluded that it is input to another signal source immediately during the test. The measuring device is further outputted to the testing device by the device to be tested, and the image to be tested can be generated by the image signal testing device, outputted to the device to be tested, and then converted and output.

FIG. 6 is a flow chart showing the steps of the embodiment of the image signal testing method of the present invention.

Beginning in step S601, the image signal testing device receives the image signal output by the device under test, such as the test pattern 60. According to an embodiment, the image signal testing device is provided with an input interface unit connected to one or more devices to be tested, and the input interface unit is provided with a circuit for determining the attributes of one or more devices to be tested and determining the format of the output image signal. The properties of the device under test are to be tested at the same time. The number of devices and the functions of each device, including image or audio output, analog output or digital output, wired output or wireless output, and even the need to confirm that the device under test has output image signals, and output image signals For the format, please refer to the various image formats shown in Figure 4 above.

Then, in step S603, after the test device receives the test signal, the circuit or the software means determines the signal format, and each signal format conforms to the specification of an image interface, so that the signal can be appropriately captured (step S605). In particular, when the signal is captured, the signal may be analogous. For example, the digital signal received by the set-top box is converted into an analog signal that can be transmitted by the television. Therefore, the captured signal includes the conversion of the signal into a test device. The signal type is, for example, converted into a digital signal by an analog signal (step S607). In the step of extracting the signal and converting the signal, a sampling procedure for confirming how many frames are captured and how many time intervals to retrieve the next frame is included (step S609), and each signal is obtained. (frame) color values, where the color values have different data in different color models, such as the aforementioned red, green, and blue pixel values, brightness, and brightness, respectively, with red, blue, etc. The difference, in another embodiment, does not preclude the brightness in the converted signal.

Then, in step S611, since the image signal testing device can receive the image signals continuously output by the device under test, such as the test pattern described above, the signals are converted and sampled, and the signal statistics are performed, for example, the foregoing calculations are averaged and standard. The statistical data worthwhile is compared with a reference value, as in step S613.

The reference value may be a pre-loaded golden value, such as one or more sets of reference patterns, the reference value may not be an accurate value, but may be a set range, so the step may be based on the color of the aforementioned sampling. value After the operation is compared with the reference value, the signal quality is dropped (step S615), and the result can be outputted in a report, a chart, or the like (step S617). For example, the signal quality is represented by a color distribution map, and the color distribution map is displayed. The performance of various colors, judging whether it is average, and reaching a certain level, can clearly indicate the state of the image output by the device under test to classify the image quality of the device to be tested.

According to the test procedure disclosed above, the content of the test is not only a state in which a plurality of test patterns continuously output are simulated as a moving image, but also a state in which a static image is played when a test pattern is transmitted.

It is worth mentioning that, in order to avoid the error of evaluation of different image capture cards, different image playback devices, and chromatic aberrations between different pixels on the test image, the method proposed by the present invention preferably can be captured by an image. Taking at least one test pattern outputted by one or more devices to be tested, and also receiving signals of a plurality of image images output by a device under test, for example, taking at least 10 pixels for each color on the test pattern The color value, then take the arithmetic mean and standard deviation, and add or subtract the range of at least 2 standard deviations from the arithmetic mean as the condition for the test pass.

In addition, at least two image capture cards can still capture at least one test image output by the same video playback device, and take the color value of at least 10 pixels of each color, and take the arithmetic mean and standard deviation thereof to The range of the arithmetic mean plus or minus at least 2 standard deviations is taken as the condition for the test pass.

Assuming that the test pattern is a pattern composed of RGB, the image capture card respectively captures the color values of the red 10 pixels on the test pattern output by the same device under test, for example, the red (R) pixel value is equal to 250, 246, 235, 248, 252, 225, 231, 243, 221, 236, and is taken. The arithmetic mean is 238.7 and the standard deviation is 10.77. If two standard deviations are taken, the standard range of the red test in the test image is R=217~255.

For a related connection relationship, an example of the test achieved by the image signal test apparatus of the present invention shown in Figs. 7A to 7C can be referred to.

FIG. 7A shows a device to be tested 701. The image capture card 702 of the image signal test device generates a test pattern displayed as 703. The test pattern is calculated by the foregoing calculation core, and the reference value is compared. Image quality.

7B, the example shows a device to be tested 701, and simultaneously outputs two identical or different test patterns to the image capture card 702 and the image capture card 704, and simultaneously generates the tests indicated by 703 and 705. The pattern, in the same way, after the test pattern is sampled, the color value is calculated, and the data for comparison is generated.

FIG. 7C then shows that the image capture card 702 of the image signal test device is connected to the device under test 701 and the device under test 706, and the test patterns for evaluation can be simultaneously generated by 703 and 705.

In summary, the present invention provides an image signal testing method and a device for implementing the testing method, thereby capable of measuring the image output quality of the device under test, and the device to be tested can be an electronic device having a plurality of image signals, The image signal 埠 continuously outputs test patterns, and the method will evaluate these test patterns, thereby achieving an image test solution with simple and low hardware requirements.

However, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Therefore, equivalent structural changes that are made by using the specification and the contents of the present invention are equally included in the present invention. Within the scope, it is combined with Chen Ming.

11‧‧‧Image signal source

10‧‧‧Image signal test device

101‧‧‧Signal capture unit

102‧‧‧Sampling unit

103‧‧‧storage unit

104‧‧‧Computation unit

105‧‧‧Result output unit

12‧‧‧ Test results

21‧‧‧Test signal

200‧‧‧Signal conversion device

20‧‧‧Image signal test device

201‧‧‧Input interface unit

202‧‧‧Signal capture module

203‧‧‧Signal Conversion Module

204‧‧‧Signal sampling module

205‧‧‧Statistical unit

206‧‧‧Comparative unit

207‧‧‧Result output unit

208‧‧‧Output interface unit

291‧‧‧ threshold

292‧‧‧ Code

293‧‧‧ test signal

294‧‧‧ reference value

22‧‧‧Report output

23‧‧‧Signal Processing Unit

209‧‧‧ storage unit

30‧‧‧Image signal test device

31‧‧‧Test signal

300‧‧‧Device under test

32‧‧‧ test results

301‧‧‧First port

302‧‧‧First connection

303‧‧‧Second connection

304‧‧‧Second connection

305‧‧‧ Third port

306‧‧‧ third connection

307‧‧‧fourth link

308‧‧‧4th connection

309‧‧‧Testing Computational Core

310‧‧‧Output interface unit

40‧‧‧Image signal test device

41‧‧‧Video conversion device

411‧‧‧First image file

412‧‧‧Second image file

413‧‧‧ Third image file

414‧‧‧ Fourth image file

415‧‧‧ Fifth image file

416‧‧‧ Sixth image file

401‧‧‧Signal input interface unit

403‧‧‧Testing Computational Core

405‧‧‧Output interface unit

42‧‧‧ test results

60‧‧‧ test pattern

701‧‧‧Device under test

702‧‧‧Image capture card

703, 705‧‧‧ output

704‧‧‧Image Capture Card II

706‧‧‧Device under test II

Step S601~S617‧‧‧Image test procedure

1 is a schematic diagram of an embodiment of an image signal testing apparatus according to the present invention; FIG. 2 is a second schematic diagram of an embodiment of an image signal testing apparatus according to the present invention; and FIG. 3 is a diagram showing a test execution using the image signal testing apparatus of the present invention. Figure 4 shows a schematic diagram of a connection diagram for performing a test using the image signal test apparatus of the present invention; Figures 5A to 5G schematically show an embodiment of a test pattern utilized by the present invention; Steps of an embodiment of an image signal test method; and FIGS. 7A to 7C are diagrams showing an example of a test achieved by the image signal test apparatus of the present invention.

11‧‧‧Image signal source

10‧‧‧Image signal test device

101‧‧‧Signal capture unit

102‧‧‧Sampling unit

103‧‧‧storage unit

104‧‧‧Computation unit

105‧‧‧Result output unit

12‧‧‧ Test results

Claims (18)

An image signal testing method includes: providing an image signal testing device, wherein the image signal testing device is provided with a plurality of connection ports for receiving image signals, thereby receiving at least one image signal output by the device to be tested; and the image signal testing device determines the At least one signal format of the image signal outputted by the device to be tested, each of the signal formats conforming to an image interface specification; the image signal testing device captures the image signal output by the at least one device to be tested; wherein the output image signal is continuous output One or more test patterns including multiple colors; performing analog image signals into digital image signals, converting the one or more test patterns into digital image signals, and performing signal sampling on the digital image signals for conversion The actual color value in the subsequent signal, wherein the image signal of the actual color value captured is converted into a signal that is compared with one or more sets of reference values; and the actual color value of the sampled digital image signal is compared with the One or more sets of reference values to determine the quality of the image signal. The image signal test method of claim 1, wherein the step of determining the attribute of the device to be tested is performed before receiving the image signal output by the at least one device under test. The image signal test method of claim 2, further comprising the step of determining the number of devices to be tested connected to the image signal test device, and confirming that the device under test has output an image signal. The image signal testing method described in claim 1 of the patent application, wherein The device to be tested is an electronic device having a plurality of image signals, and the plurality of image signals of the device to be tested are simultaneously connected to an input interface of the image signal testing device. The image signal test method of claim 4, wherein the device to be tested is a video conversion and/or playback device for converting an input signal into an image signal. The image signal testing method of claim 1, wherein the signal sampling step captures a color value in the converted signal, and further comprises receiving the image signal from the at least one device under test if the sampling is insufficient. A step of. The image signal test method according to claim 6, wherein the color value includes a pixel value of red, green, and blue, or a difference between brightness and brightness and red and blue, respectively. The image signal test method according to claim 6, wherein the sampled color value is compared with the one or more sets of reference values after an average operation. The image signal test method of claim 1, wherein the signal sampling step captures a brightness value in the converted signal. The image signal test method according to claim 1, wherein the signal quality is represented by a color distribution map. The image signal testing method according to claim 1, wherein the signal quality is used to classify the image quality of the device to be tested. An image signal testing device for performing the image signal testing method according to claim 1, comprising: an input interface unit connected to one or more devices to be tested, wherein the input interface unit is configured to determine the one or more to-be-tested Measure the properties of the device And a circuit for determining the format of the output image signal; a signal processing unit electrically connected to the interface input unit, comprising: a signal acquisition module implemented by a circuit or a software, for capturing the one or more to-be One or more image signals output by the measuring device; a signal conversion module implemented by a circuit or a software for converting the one or more image signals into signals for comparison; a signal sampling by circuit or software a module for sampling a signal and obtaining a color value; a storage unit for temporarily storing the color value, coupled to the signal processing unit, and storing at least the code for the operation of the image signal testing device and the signal comparison a reference unit; a computing unit that obtains the color value by the storage unit to perform color evaluation, coupled to the storage unit; and an output interface unit that outputs a comparison result, coupled to the computing unit and the storage unit. The image signal testing device of claim 12, wherein the input interface unit is provided with a plurality of ports compliant with a plurality of image interface specifications. The image signal testing device according to claim 12, wherein the calculating unit comprises a statistical unit that calculates one of the color values and a comparing unit that performs the comparison. The image signal testing device according to claim 14, wherein the comparing unit is configured to compare a color average value obtained by the statistical unit and the reference value. The image signal testing device of claim 15, wherein the one or more image signals output by the one or more devices to be tested are one or more test patterns including multiple colors that are continuously output. The image signal testing device of claim 12, wherein the device to be tested is an electronic device having a plurality of image signals, and the plurality of image signals of the device to be tested are simultaneously connected to the input interface unit. The video signal testing device of claim 17, wherein the device to be tested is a video conversion and/or playback device for converting an input signal into an image signal.