Patent ID: 12198223

DETAILED DESCRIPTION

FIG.1is a block diagram of an on-vehicle display system1according to an embodiment of the invention. The on-vehicle display system1may be implemented on a vehicle to offer reliable information display while reducing the memory usage.

The on-vehicle display system1may include a display panel10, a host processor18and a controller circuit12. The controller circuit12may be implemented in a driver integrated circuit (IC), a display driver, a timing controller, or other display control circuits. The display panel10may be a touch panel, and may display an image of a speedometer. The controller circuit12may be coupled to the display panel10and the host processor18. Further, the controller circuit12may be arranged physically close to the display panel10and far apart from the host processor18. Furthermore, the controller circuit12may locally store images/parameters of pieces of safety information, and receive a command from the host processor18to generate safety information images using the images/parameters of the pieces of safety information, so as to generate an output image to be displayed on the display panel10. In some embodiments, each piece of safety information may be an on-screen display (OSD) character, each safety information image may be an OSD image, and the output image may be an overlay image of overlaying the safety information images on a background image. In some embodiments, the output image may be a vehicle digital dashboard including driving information, road safety information, and/or mode control, and may be crucial for driving safety. The close arrangement between the controller circuit12and the display panel10may ensure an accurate and reliable display of the vehicle digital dashboard, leading to improvement of the driving safety.

The controller circuit12may include an image mixer121, safety information buffers1221to122M, a background buffer123, parameter memories1241to124N, and image memories1251to125N. N, M may be positive integers, and N may be equal to or different from M, e.g., N=10, M=3. The image mixer121may be coupled to the safety information buffers1221to122M and the background buffer123. Each of the safety information buffers1221to122M may be coupled to the image memories1251to125N and the parameter memories1241to124N.

The image memories1251to125N may store N images of N pieces of safety information. The parameter memories1241to124N may store N sets of parameters of the N pieces of safety information. The pieces of safety information may be numbers, alphabets, symbols, and the like, and may be different from each other. The images of the pieces of safety information may be bitmap data of the pieces of safety information. Each set of parameters of a piece of safety information may include a color scheme, a transparency level, position coordinates, a resolution setting, a scaling factor, a width, and/or a length of the piece of safety information. For example, if N=10, the 10 pieces of safety information may be digits 0 to 9, the image memories1251to12510may respectively store bitmap data of the digits 0 to 9, and the parameter memories1241to12410may each store a color scheme, a transparency level, position coordinates, a resolution setting, a scaling factor, a width, and/or a length of one of the digits 0 to 9. In the embodiment, the image memories1251to125N may be implemented by static random-access memories (SRAM), and the parameter memories1241to124N may be implemented by data registers, while in other embodiments, other types of volatile memories may be used for implementing the image memories1251to125N and/or the parameter memories1241to124N.

Prior to generation of an output image, all pieces of safety information used in the output image must be ready. Therefore, each of the safety information buffers1221to122M may buffer an image of a selected piece of safety information and a set of parameters of the selected piece of safety information, the selected piece of safety information being selected from the N pieces of safety information to be used in the output image. Accordingly, the safety information buffers1221to122M may buffer M images of M selected pieces of safety information and M sets of parameters of the M selected piece of safety information. The M selected pieces of safety information may be identical or different from each other. In some embodiments, two or more of the M selected pieces of safety information may be identical to each other. For instance, if M=3 and all the 3 selected pieces of safety information are the digit 1, each of the safety information buffers1221to1223may hold the image of the digit 1 and the set of parameters of the digit 1. In this fashion, the images of the pieces of safety information in the image memories1251to125N and the sets of parameters of the pieces of safety information in the parameter memories1241to124N may be reused to generate an output image, reducing the usage of the image memories1251to125N and the parameter memories1241to124N, and reducing the manufacturing cost. The safety information buffers1221to122M may be line buffers implemented by SRAM.

The background buffer123may store a background image, and may be a line buffer implemented by SRAM. The background image may be a still image or a video image. The image mixer121may load the M images of M selected pieces of safety information and M sets of parameters of the M selected pieces of safety information from the safety information buffers1221to122M, generate M safety information images according to M images of M selected pieces of safety information and M sets of parameters of the M selected pieces of safety information, and combine the M safety information images and the background image to generate an output image, and output the output image to the display panel10. In some embodiments, the image mixer121may map colors of the M safety information images according to the respective color schemes, set the transparencies of the M safety information images according to the respective transparency levels, modify the resolutions of the M safety information images according to the respective resolution settings, scale the M safety information images according to the respective scaling factors, the respective widths and the respective lengths, and overlay the M safety information images on predetermined regions on the background image according to respective position coordinates to generate the output image. The processes of generating the output image merely serve as an example, a person skilled in the art would recognize that the image mixer121may process the M safety information images in a variety of fashions to provide favorable image quality of the output image for displaying on the display panel10.

The controller circuit12may further include a command interface127configured to receive a command from the host processor18, and in response to the command, the safety information buffers1221to122M may receive the M images of the M selected pieces of safety information and the M sets of parameters of the M selected pieces of safety information according to the command. The command interface127may be an inter-integrated circuit (I2C) interface, a serial peripheral interface (SPI), or other communication interfaces.

The on-vehicle display system1may further include a flash memory14coupled to the image memories1251to125N and the parameter memories1241to124N. Upon initialization of the on-vehicle display system1, the image memories1251to125N may retrieve the N images of N pieces of safety information from the flash memory14, and the parameter memories1241to124N may retrieve the N sets of parameters of the N pieces of safety information from the flash memory14.

The controller circuit12may further include a low voltage differential signaling (LVDS) interface126configured to receive the background image from a graphics processing unit (GPU)16. In some embodiment, the LVDS interface126may be replaced by other video interfaces such as a DisplayPort interface, a digital visual interface (DVI), or a high-definition multimedia interface (HDMI). In some embodiments, the GPU16and the host processor18may be integrated into one single processor.

The controller circuit12may further include a data processor120coupled to the image mixer121. The data processor120may receive the output image from the image mixer121, apply gamut mapping to the output image using a color lookup table to generate a corrected output image, and generate control signals according to image data of the corrected output image to control gate drivers and source drivers of the display panel10to display the corrected output image.

In the related art, each the safety information image can be retrieved from only an SRAM address of a conventional controller circuit. Consequently, the conventional controller circuit employs 10 SRAMs holding images of numbers 0 to 9 for a single-digit display in a speedometer, and employs 30 SRAMs holding images of numbers 0 to 9 for a three-digit display in the speedometer. Compared to the related art, the controller circuit12employs only 10 SRAMs for a three-digit display in the speedometer, reducing by ⅔ of the memory usage in the related art, displaying the safety information images on the display panel10in a reliable manner regardless of the host processor18being operated in normal or abnormal conditions, significantly enhancing driving safety of the driver.

While only one controller circuit12is adopted in the embodiment inFIG.1, other numbers of controller circuits12may be adopted.FIG.2is a schematic diagram of an on-vehicle display system2adopting two controller circuits12aand12baccording to another embodiment of the invention. The on-vehicle display system2is similar to the on-vehicle display system1, except that controller circuits12aand12bare adopted in the on-vehicle display system2, other components of the on-vehicle display system2are similar to the on-vehicle display system1and may not be shown inFIG.2. The following discussion will be focused on the controller circuits12aand12band the display panel10of the on-vehicle display system2.

The display panel10may display output images including regions100,102,104, and201to2010for displaying a vehicle digital dashboard. The positions and dimensions of the regions100,102,104, and201to2010may be defined by the respective position coordinates, widths and lengths as in the sets of parameters of the selected pieces of safety information. The pieces of safety information may be related to driving information such as speedometer data and fuel meter data, road safety such as the engine temperature and the airbag warning indicator, and/or mode control such as turning-on a mode or turning-off a mode. The vehicle digital dashboard may include a digital speedometer in regions100,102,104and207, a digital fuel meter in the region209, an engine temperature meter in the region2010, a driving mode in the region208, and various warning indicators in the regions201to206.

The controller circuits12amay include image memories1251ato12510ato hold images of the digits 0 to 9, respectively, to generate a first output image including the regions100,102and104. The controller circuits12bmay include image memories1251bto12510bto hold images of the various warning indicators, a speedometer unit, the driving mode, the digital fuel meter, and the engine temperature meter, respectively, to generate a second output image including the regions201to2010. The controller circuits12amay include parameter memories matching the image memories1251ato12510afor use to hold the sets of parameters for generating the first output image, and the controller circuits12bmay include parameter memories matching the image memories1251bto12510bfor use to hold the sets of parameters for generating the second output image.

Accordingly, the images and sets of parameters of identical pieces of safety information may be loaded from the same image memory and parameter memory to reduce the usage of the memories in the on-vehicle display system2, and reduce the manufacturing cost. For example, if a number “111” is to be displayed in the first output image, the images and sets of parameters of the digit 1 may be loaded 3 times from the same image memory1251aand the same matching parameter memory to derive the first output image.

FIG.3is a schematic diagram of the on-vehicle display system1according to another embodiment of the invention.FIG.3shows a slider control bar for switching a mode in the on-vehicle display system1. For example, the mode may be an anti-lock braking mode, a user may swipe right the slider control icon with a finger to turn on the anti-lock braking mode.

The display panel10may display an output image including a region300. The controller circuit12may include an image memory1251to hold an image of the slider control icon and a matching parameter memory to hold a set of parameters of the slider control icon. The position and dimension of the region300may be defined by the respective position coordinates, width and length as in the set of parameters of the slider control icon. The on-vehicle display system1may generate a safety information image of a slider control bar according to the image and the set of parameters of the slider control icon, generate the output image to be displayed in the region300according to the safety information image, and output the output image to the display panel10.

FIG.4is a schematic diagram of the on-vehicle display system1according to another embodiment of the invention.FIG.4shows a soft key control for switching a mode in the on-vehicle display system1. For example, the mode may be the anti-lock braking mode, a user may touch or apply pressure to the soft key to turn on/off the anti-lock braking mode.

The display panel10may display an output image including a region400. The controller circuit12may include an image memory1251to hold an image of the soft key icon and a matching parameter memory to hold a set of parameters of the soft key icon. The position and dimension of the region400may be defined by the respective position coordinates, width and length as in the set of parameters of the soft key icon. The on-vehicle display system1may generate a safety information image of the soft key according to the image and the set of parameters of the soft key icon, generate the output image to be displayed in the region400according to the safety information image, and output the output image to the display panel10.

Accordingly, the on-vehicle display systems inFIGS.1to4employ limited quantities of the image memories and parameter memories in the controller circuit to ensure an accurate and reliable display, while employing the safety information buffers in the controller circuit to reduce the usage of image memories and parameter memories and reduce the manufacturing cost.

Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.