DE102006005078B4 - Method and test system for testing an image signal generating device - Google Patents

Abstract

Apparatus (10) for producing image data from image signals, comprising - an input (14) for connecting the apparatus (10) to an image signal output (6) of a computer (1) by means of an image signal cable (21) for image signals, - an image data memory (12 ), - an image data generator (11) adapted to convert image signals applied to the input (14) to image data and to store them in the image data memory (12), - an output (15) for image data, a connectivity according to the USB specification comprising: - an output unit (13) arranged to provide the content of the image data memory (12) at the output (15) for image data in serial form according to the USB specification, and - another output (16) for connecting the device (10) via another image signal cable (23) with a playback device (20) which is connected to the input (14) and at which the signal applied to the input (14) again a is given.

Description

The invention relates to a method and a test system for testing an image signal generating device and also to an apparatus for producing image data from image signals, a computer program product with program code for carrying out the method and a production method for a computer.

As an image signal generating device, a device is designated which generates an image signal from image data, which is a display unit, for. B. is supplied to a computer monitor to reproduce the image encoded in the image data present on the display device.

An example of an image signal generating device is a graphics card of a computer, wherein in the meaning of the application, the graphics card can also be integrated in the form of a graphics unit on the motherboard of the computer ("graphics on board"). In a memory predetermined image data representing a rasterized, consisting of individual pixels image to be displayed, are converted by such a graphics card into an image signal, which is transmitted via appropriate connections on the computer a monitor for display. The memory for the image data can optionally be arranged on the graphics card itself or be part of a working memory of the computer. The image data in the memory typically represented the image in the form of a bitmap in which one or more color and / or brightness values are stored for each pixel of the image to be displayed.

The generated image signal may be an analog or digital signal. A well-known specification for analog video signals is VGA (video graphics adapters) and digital video signals DVI (digital visual interface). An image signal can be transmitted via several parallel signal line, z. B. by providing separate signal line for each of the three primary colors.

An important step in a computer manufacturing process is a functional test of both the individual components and the overall device. Even with functional individual components, the interaction of the components to a functional overall device is not necessarily given. For testing an image signal generating device, in particular within an overall device, therefore, an image signal generated by the image signal generating device on a reproducing device is manually checked by a test person, which is laborious and also erroneous.

From the US 5,920,340 For example, a method and apparatus for self testing a multimedia subsystem are known. The self-test is accomplished by fetching a pattern from a first memory area, the fetch being by a graphics card. Once the pattern has been retrieved, the graphics card provides it to a video capture card via a television encoder. Upon receiving the pattern, the video capture card generates a captured pattern thereof. The captured pattern is then transferred from the video capture card to a memory via the graphics card. Once the detected pattern is stored in memory, the detected pattern may be compared to the original pattern. If the comparison fails, among other things, the video capture card and a connection path have passed the self-test.

It is an object of the invention to provide a simple and reliable test facility for image signal generating apparatus.

This object is achieved by a device for generating image data from image signals according to claim 1, a test system for testing an image signal generation device according to claim 10 and a production method for a computer according to claim 17.

According to the described method, reliable testing of the image signal generating device is enabled by specifying test image data of a test image to the image signal generating device. Image signals generated by the image signal generation device are output and transmitted to a device configured to generate image data from image signals. Image data created and output by the device are read in and compared with the predetermined test image data. Depending on the result of the comparison, a test result is then determined. Thus, according to the present invention, by comparing image data reconstructed from the image signals of an image signal generating device with the original predetermined image data, a test of the image signal generating device is enabled. The test method described can be easily automated and thus reliably performed.

This can z. B. be realized by a computer program product with program code for performing the method described.

The apparatus used in the implementation of the method for producing image data from image signals according to the invention comprises in one embodiment an input for image signals, a Image data storage and an image data generator, which is adapted to convert input image signals present in the image data and store them in the image data memory. The apparatus is characterized in that an output is provided for image data and an output unit is arranged to provide the content of the image data memory at the output for image data.

According to a further aspect of the invention, there is provided a test system for testing an image signal generating apparatus comprising an apparatus for generating image data from image signals, and a computer program product for carrying out the method for testing an image signal generating apparatus and a computer adapted to execute the program code of the computer program product , The test system is set up to transmit test image signals generated by an image signal generation device to a test image from the computer program product, to transfer image data created and output by this device back to the computer, to compare the predefined test image data with the generated image data, and depending on the image data Result of the comparison to determine a test result. In a preferred embodiment of the test system, the computer has a graphics card as an image signal generating device, and the test system is configured to test the graphics card of the computer.

In a further embodiment of the invention, a production method for a computer is specified, wherein the computer has a graphics card as an image signal generating device and the production method comprises a test of the graphics card according to the method according to the invention.

Advantageous embodiments and further developments of the invention are specified in the respective dependent claims.

In the following the invention will be explained in more detail by means of exemplary embodiments with the aid of two figures.

It shows:

1 a schematic representation of an embodiment of a test system for testing an image signal generating device and

2 a flowchart of an embodiment of a method for testing an image signal generating device.

This in 1 The test system shown for testing an image signal generating device includes a computer 1 with processor 2 , associated storage 3 as well as input and output unit 4 , With the input and output unit 4 is an image signal generating device 5 connected. Furthermore, the computer points 1 an image signal output 6 recorded with the image signal generating device 5 connected and a data input and output 7 that with the input and output unit 4 connected is. The test system further comprises a device 10 for creating image data from image signals comprising an image data generator 11 and an associated image data memory 12 and an output unit 13 having. In the device 10 are an entrance 14 , an exit 15 and another exit 16 intended. The entrance 14 is with the image data generator 11 as well as the further exit 16 connected and the output 15 with the output unit 13 , An image signal cable 21 connects the image signal output 6 of the computer 1 with the entrance 14 the device 10 , A data cable 22 connects the exit 15 the device 10 with the data input and output 7 of the computer 1 , In addition, the test system includes a playback device 20 that has another picture signal cable 23 with the further exit 16 the device 10 connected is.

This in 1 The test system shown is adapted to the image signal generating device 5 of the computer 1 to the correct output of an image signal at the image signal output 6 to test. The test system shown can be used for example in the context of a manufacturing process for computers, wherein the computer 1 in the case, on the one hand, is part of the test system and, on the other hand, with the image signal generating device 5 includes the test object as one of its components. Likewise, the test system shown could also for permanent functional monitoring of the image signal generating device 5 a computer can be used during operation. That the computer 1 as part of the test system, the image signal generating device 5 as a test object is, of course, not mandatory for the test system according to the invention. A further embodiment of a test system, not shown here, may be designed such that an (external) image signal generating device 5 that are not component of the computer 1 is, test object is.

The image signal generating device 5 can be both a graphics card that is connected to an expansion port, such. For example, an AGP (advanced graphics port) interface that is attached to the computer motherboard or already on-board graphics on the motherboard of the computer 1 be integrated.

From the computer 1 are in the figure only those essential to the invention Components shown. The presence of other components, for example a power supply or non-volatile mass storage, are taken for granted.

During normal operation of the computer 1 is the image signal output 6 via a corresponding video signal cable with the playback device 20 connected to transmit the image signal. In the image signal, the image content to be displayed is reproduced by a sequence of brightness values of individual picture elements, here the pixels. Usually, the brightness values of the three primary colors that make up a colored image are transmitted. In addition, synchronization signals may be provided. The brightness values can be coded analog or digital (analog / digital image signal), whereby different standards have been established for the signal shape and the mechanical and electrical design of the connector and cable used. In the case of analog image signals, for example, a separate signal line is usually provided for each of the primary colors as well as the synchronization signals. With digital image signals, brightness values are also transmitted for each primary color, whereby either individual signal lines (data channels) or even a common data channel can be used. The synchronization signals can also be transmitted via this data channel. For analogue image signals, the VGA (video graphics adapters) standard is to be cited here, and for digital image signals the DVI (digital visual interface) or the HDMI (High Definition Media Interface) standard.

For test operation within the test system, the image signal output is 6 of the computer 1 with the entrance 14 connected. The mechanical and electrical design of the input 14 the device 10 is here to the image signal generating device to be tested 5 customized. The entrance 14 For example, it can be exactly the input of the playback device 20 The same with the usual operation with the image signal output 6 would be connected, so z. As a tube or LCD (liquid crystal display) monitor. To connect between computers 1 and device 10 can then be used as a video signal cable 21 a standard, standardized monitor cable can be used.

Instead of a direct cable connection via the video signal cable 21 can be used for transferring the image signal from the computer 1 to the device 10 Of course, alternative transmission techniques are also used. This could be, for example, wireless transmission technologies such as wireless local area network (WLAN), ultra wide band (UWB) or Bluetooth, optical transmission techniques, e.g. Via optical fiber or IrDA (infrared data association), or network-based transmission techniques. Furthermore, the transmission can use lossless or lossy data compression.

In addition, as in the 1 shown the entrance 14 within the device 10 to the other exit 16 be looped through, with the further output 16 in its interpretation usefully the image signal output 6 of the computer 1 equivalent. About the further image signal cable 23 so can the playback device 20 parallel to the device 10 be supplied with the image signal, thereby simultaneously with the inventive automatic test of the image signal generating device 5 a manual optical control of the image signal on the playback device 20 can be done. It is also conceivable that the device 10 several inputs 14 which are designed according to different standards and which via a selection switch or a multiplexer with the image data generator 11 and the other exit 16 are connected.

The image data generator 11 is adapted to generate image data from the received image signal and these in the image data memory 12 store. The image data generator 11 is thus in its function complementary to the imaging device 5 , Devices, for example in the form of ASICs (application specific integrated circuits), with such functionality are known, for example, from LCD monitors. In the image data memory 12 the image coded in the image signal is stored in the form of a two-dimensional field (bitmap). The number of field elements corresponds to the resolution of the transmitted image, so that a field element for storing the brightness values is provided for each pixel, for example 800 × 600 pixels in the VGA standard, 1024 × 768 pixels in the extended XGA standard (extended graphics adapter) or 2048 × 1536 pixels in the so-called QXGA standard (quad-XGA). For each field element, ie every pixel, usually three brightness values are stored for the three primary colors, wherein the resolution with which the brightness values are defined is called color depth. At the moment, values between 8 and 30 bits are typical for the color depth, in the future even larger color depths are conceivable. Furthermore, the transmission of three-dimensional images in conjunction with a holographic representation is conceivable for the future. By designing the image data memory 12 As a three-dimensional field, the method and test system according to the invention can be adapted accordingly.

From the image data generator 11 Thus, the brightness values of individual picture elements which are transmitted sequentially in the picture signal are taken into account, taking into account the picture signals contained in the picture signal Synchronization signals written in the corresponding field elements of the image data memory. In the evaluation of analog image signals, this requires a digitization of the analog signals transmitted by a digital-to-analog converter with a resolution corresponding to the color depth. In the image data memory 12 This results in a reconstruction of the image from which the image signal generating device 5 has generated the image signal.

The output unit 13 is set up to use the image data memory 12 read out and its contents at the exit 15 to provide. About the data cable 22 as well as the data input and output 7 and the input and output unit 4 becomes the contents of the image data memory 12 to the computer 1 transmit and, stored there and become the processor 2 thus available for processing. The transmission of the image data can be done in a serial or parallel way. For a serial transmission in particular a transmission according to the USB (universal serial bus) specification is suitable due to the achievable high data transmission rates. In addition, computers usually have one or more suitable data inputs and outputs as standard 7 according to the USB specification. About the data cable 22 can continue to supply power from the computer according to the USB specification 1 to the device 10 be transmitted. This allows the device 10 be advantageously constructed without a separate power supply device.

As with the transmission of the image signal is also here instead of a direct connection via the data cable 22 the use of alternative transmission techniques (eg wireless, optical, network-based) conceivable.

In a further embodiment of the device 10 can the output 15 be designed as input and output for bidirectional data transmission. In addition to the image data taken by the device 10 to the computer 1 can be transmitted via the input and output unit 4 , the data cable 22 and the exit 15 also for transmission of control signals from the computer 1 to the device 10 be used. Such control signals can, for. B. Synchronization signals for controlling the test procedure include or can be used to control a multiplexer in the device 10 may be provided to multiple inputs 14 optionally with the image data generator 11 connect to.

The execution of a test method for testing the image signal generating device 5 through the in 1 shown test system is described below with reference to 2 explained in more detail.

The method of testing the image signal generating device 5 begins in step S1 with the test image data of a test image to the image signal generating device 5 be specified. The procedure is carried out on the computer 1 from the processor 2 who executes a corresponding computer program product with program code for carrying out the method.

As an additional step, before the transfer of the test image data to the image signal generating device 5 a configuration of the image signal generating device 5 done by which the image signal generating device 5 in a certain predetermined operating mode in which the test is to be performed is set. The operating mode in this context refers, for example, to the set screen resolution, ie the number of pixels in horizontal or vertical orientation or to the color depth with which individual pixels are reproduced.

In step S2 of the method, the image signal generating device generates 5 from the predetermined test image data, an image signal which in step S3 at the image signal output 6 is issued.

That of the image signal generating device 5 output image signal is transmitted via the image signal cable 21 to the device 10 transferred and read in step S4.

In step S5, the image data generator generates 11 image data from the adjacent image signals and store them in the image data memory 12 from. In this case, the image data generator 11 be set up so that the image data is continuously in the image data memory 12 be written according to the applied image signals. Alternatively, the image data generator 11 also be set up so that at the request of the computer 1 Image data of a single image in the image data memory 12 to be written. A transmission of an appropriate request can z. B. on the input and output unit 4 , the data cable 22 and exit 15 take place, which must be designed in the case correspondingly for bidirectional data exchange.

In step S6, the output unit 13 the content of the image data memory 12 at the exit 15 provided and via the data cable 22 to the computer 1 transfer.

The computer 1 receives in step S7 via the data input and output 7 and the input and output unit 4 the contents of the image data memory 12 and save him in his store 3 from. The transmission of data from the device 10 to the computer 1 can do this, for example, at the request of the computer 1 happen.

In the storage room 3 of the computer 1 then both the test image data specified in step S1 and the image data received in step S7 and reconstructed on the basis of the image signals are located in the image data memory 12 in front. These are compared pointwise with one another in step S8 of the method. If the image data from the image data memory 12 coincide with the test image data, in step S9, a corresponding message that the image signal generating device 5 otherwise, in step S10, the improper operation of the image signal generating device is performed 5 pointed.

The comparison in step S8 can be designed so that a match of image data and test image data is given only if all the brightness components for all pixels have exactly the same value. However, this very strict criterion is only suitable for digital image signals in practice. In analog image signal transmission, the brightness values of pixels in the image signal generation apparatus become 5 first analogized by a digital-to-analog converter and then in the image data generator 11 converted back to digital values by an analog-to-digital converter. Especially at high resolution color depths (greater than about 16 bits), deviations between the brightness values of the given test value data and those of the reconstructed image data are unavoidable. In such a case, a certain tolerance limit may be predetermined for the comparison in step S8, by which the brightness values of test image data and image data may differ without the comparison being negative. Even with digital image signal transmission, a tolerance limit may be useful, eg. B. if lossy data compression is used in the transmission of the image signal.

In an alternative embodiment of the method, it is possible, after step S9, to set the method for a different operating mode of the image signal generating device 5 to repeat, for example, another resolution. A final positive test result is only output if the comparison in step S8 is positive in all intended operating modes.

Furthermore, it is possible to specify a test image sequence (video sequence) instead of a static test image. Because the data transfer via the data cable 22 usually has no sufficient bandwidth to the image data of all frames of the test image sequence in real time to the computer 1 In this case, it is expedient to be able to transmit the image data memory 12 be designed in its capacity so that several images can be stored separately, which then successively to the computer 1 transfer. In such a case, in turn, the connection via the input and output unit 4 , the data cable 22 and exit 15 between the computer 1 and the device 10 be used in a bidirectional embodiment to transmit control signals for synchronizing the generation and transmission of the image data with the start of the test image sequence.

LIST OF REFERENCE NUMBERS

1

computer

2

processor

3

Storage

4

Input and output unit

5

Image signal generating device

6

Image signal output

7

Data input and output

10

contraption

11

Image data generator

12

Image data storage

13

output unit

14

entrance

15

output

16

another exit

20

Playback device

21

Image signal cable

22

data cable

23

another image signal cable

Claims (17)

Contraption ( 10 ) for generating image data from image signals, comprising - an input ( 14 ) for connecting the device ( 10 ) with an image signal output ( 6 ) of a computer ( 1 ) by means of an image signal cable ( 21 ) for image signals, - an image data memory ( 12 ), - an image data producer ( 11 ), which is set up at the entrance ( 14 ) convert existing picture signals into picture data and store them in the picture data memory ( 12 ), - an output ( 15 ) for image data comprising a connectivity according to the USB specification, - an output unit ( 13 ), which is adapted to the contents of the image data memory ( 12 ) at the exit ( 15 ) for image data in serial form according to the USB specification, and - another output ( 16 ) for connecting the device ( 10 ) via another video signal cable ( 23 ) with a playback device ( 20 ), with the entrance ( 14 ) and at which the at the entrance ( 14 ) applied image signal is output again. Contraption ( 10 ) according to claim 1, characterized in that the image data generator ( 11 ) is set up at the entrance ( 14 ) for image signals applied to convert digital image signals into image data. Contraption ( 10 ) according to claim 2, characterized in that the image data generator ( 11 ) is adapted to convert digital image signals according to the DVI-D specification and / or the HDMI specification. Contraption ( 10 ) according to one of claims 1 or 2, characterized in that the input ( 14 ) includes a connection option according to the DVI-D and / or DVI-I specification and / or the HDMI specification. Contraption ( 10 ) according to claim 1, characterized in that the image data generator ( 11 ) is set up at the entrance ( 14 ) for image signals applied analog image signals to convert image data. Contraption ( 10 ) according to claim 5, characterized in that the image data generator ( 11 ) is adapted to convert analog image signals according to the DVI-A specification. Contraption ( 10 ) according to one of claims 5 or 6, characterized in that the input ( 14 ) comprises a connection facility according to the DVI-A and / or DVI-I specification. Contraption ( 10 ) according to claim 5, characterized in that the image data generator ( 11 ) is adapted to convert analog image signals according to the VGA specification. Contraption ( 10 ) according to one of claims 5 or 8, characterized in that the input ( 14 ) includes a connection option according to the VGA specification. Test system for testing an image signal generating device ( 5 ), comprising - a device ( 10 ) according to one of claims 1 to 9, - a computer ( 1 ) with the image signal generating device ( 5 ), - a first image signal cable ( 21 ), which has an image signal output ( 6 ) of the computer ( 1 ) with the entrance ( 14 ) of the device ( 10 ), - a data cable ( 22 ) according to the USB specification, which determines the output ( 15 ) of the device ( 10 ) with a data input and output ( 7 ) of the computer ( 1 ), - a playback device ( 20 ) and - a second image signal cable ( 23 ), the further output ( 16 ) of the device ( 10 ) with the playback device ( 20 ), wherein the test system is set up, - with the image signal generating device ( 5 ) of the computer ( 1 ) To generate test image signals of a given test image and via the first image signal cable ( 21 ) to the device ( 10 ), - at the entrance ( 14 ) of the device ( 10 ) applied image signal at the further output ( 16 ) of the device ( 10 ), - of the device ( 10 ) generated and output image data serially via the data cable ( 22 ) to the computer ( 1 ), - the given test image data in the computer ( 1 ) to compare with the created image data and - depending on the result of the comparison to determine a test result. The test system of claim 10, wherein the test image data and / or the image data comprises brightness and / or color information for a plurality of pixels. The test system of claim 11, wherein the test result is negative if the brightness and / or color information for more than a predetermined number of pixels of the predetermined test image data and the created image data do not match. The test system of claim 11, wherein the test result is negative if the brightness and / or color information for more than a predetermined number of picture elements of the predetermined test image data and the created image data differs by more than a predetermined tolerance value, respectively. A test system according to any one of claims 10 to 13, wherein prior to providing the test image data, a control instruction for setting an operating mode is transmitted to the image forming apparatus. Test system according to one of Claims 10 to 14, in which, for a sequence of predetermined test image data from the computer ( 1 ) Image signals and to the device ( 10 ) and serial image data created and output by the device to the computer ( 1 ) and compared with the created image data before the test result is determined. Test system according to one of claims 10 to 15, wherein the computer ( 1 ) a graphics card as an image signal generating device ( 5 ) and wherein the test system is adapted to the graphics card of the computer ( 1 ) to test. Manufacturing method for a computer ( 1 ), whereby the computer ( 1 ) an image signal generating device ( 5 comprising a test of the image signal generating device ( 5 ) with a test system according to one of claims 10 to 16.

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