CN104702878A - Method for differentiating OSD and Video signals based on HDMI protocol - Google Patents

Abstract

The invention provides a method for differentiating OSD and Video signals based on an HDMI protocol. The method comprises the steps of 1) dividing image signals transmitted by the HDMI into blocks and marking signal types by the blocks, 2) marking the types of the image signals transmitted by the HDMI differently by use of flag bits, and separately processing the Video and OSD signals without reducing the image signal quality, and 3) estimating the image information of the flag bits for marking the signal types by use of pixels in neighborhoods, thereby further improving the image signal quality. According to the method, the Video and OSD signals are fused before transmission, so that the transmission bandwidth and the data storage space can be reduced; during image processing, the Video and OSD signals are processed separately, so that a good display effect can be ensured.

Description

Based on the method distinguishing OSD and Video signal under HDMI agreement

Technical field

The present invention relates to display screen technology field, more specifically, relating to a kind of method based on distinguishing OSD and Video signal under HDMI agreement.

Background technology

The display terminal that image is play can show two kinds of signals: Video signal and osd signal.Wherein Video signal is the external image vision signal received by display device input interface; Osd signal be screen display comprise that the process of the image frame such as DVD player, television receiver is relevant with display arranges menu signal.In image frame display device, to some process operation (as frame rate conversion, process such as Color Gamut Mapping) of input signal, differentiation Video signal and osd signal is needed then optionally to process, the display result just can guaranteed.If but Video signal and osd signal separately being carried out transmission stores, then can propose very high requirement to transmission bandwidth and data space, be unfavorable for hardware implementing.

Summary of the invention

The present invention is directed to the technical problem existed in above-mentioned prior art, a kind of method based on distinguishing OSD and Video signal under HDMI agreement being provided, reducing transmission bandwidth and data space, ensure that good display result.

For achieving the above object, the technical solution adopted in the present invention is as follows:

Based on the method distinguishing OSD and Video signal under HDMI agreement, comprise step as follows:

1), by the signal of video signal that HDMI transmits carry out the division of block, carry out marking signal type by block;

2), service marking position carrys out the signal of video signal type that separator HDMI transmits, and Video and osd signal carried out separately process under the prerequisite not reducing signal of video signal quality;

3), to the flag bit being used to marking signal type, utilize the pixel in neighborhood to estimate the image information that it is original, improve signal of video signal quality further.

Described 1) specifically: the block signal of video signal that HDMI transmits being divided into M × N size, wherein, it is Video signal or osd signal that each block will mark this block by a flag bit, raising system processing speed, suppose that image size is Wd × Ht, then the value of M, N is the arbitrary value in 1 ~ Wd, 1 ~ Ht.

The value of M, N is even number.

M＝N。

Described 2) specifically: to each block, the bit i-bit choosing one of them pixel is as flag bit, and being used for marking corresponding block is Video signal or osd signal, i value 1 ~ M × N.

i＝1。

Described 3) specifically: adopt neighborhood information to carry out the signal of video signal of recovering mark position, in signal processing, pixel component containing flag bit have lost the image information contained by itself, if do not repaired, then can reduce signal of video signal quality, utilize the pixel in its a certain size neighborhood, adopt interpolation to solve the image information of its loss, promote and recover signal of video signal quality.

Based on the contiguous range of different size, adopt different interpolation algorithms.

Technique scheme of the present invention, the beneficial effect brought is as follows:

According to the inventive method, transmit after Video signal and osd signal can being merged, reduce transmission bandwidth and data space; During image processing, the separately process of Video signal and osd signal, ensure that good display result.

Accompanying drawing explanation

By reading the detailed description done non-limiting example with reference to the following drawings, other features, objects and advantages of the present invention will become more obvious:

Fig. 1 is block schematic diagram in one embodiment of the invention;

Fig. 2 is current block and neighborhood block position view in one embodiment of the invention;

Fig. 3 is the method schematic diagram indicating in Fig. 2 embodiment that place value is identical;

Fig. 4 carries out to Fig. 3 the method schematic diagram that interpolation solves;

Fig. 5 indicates place value diverse ways schematic diagram in Fig. 2 embodiment;

Fig. 6 carries out to Fig. 5 the method schematic diagram that interpolation solves.

Embodiment

Below in conjunction with specific embodiment, the present invention is described in detail.Following examples will contribute to those skilled in the art and understand the present invention further, but not limit the present invention in any form.It should be pointed out that to those skilled in the art, without departing from the inventive concept of the premise, some distortion and improvement can also be made.These all belong to protection scope of the present invention.

Method based on distinguishing OSD and Video signal under HDMI agreement provided by the present invention, embodiment as shown in Figure 1, selects in the lower right corner pixel of 2 × 2 pieces and contributes the lowest bit position 1-bit of little component as flag bit, as in Fig. 1 to visual effect shown in.If have pixel to belong to osd signal in these 2 × 2 pieces, then mark position 1, otherwise set to 0.

In shown in Fig. 1 ~ Fig. 6, represent the pixel of flag bit; represent the pixel not containing flag bit; represent the neighborhood territory pixel being used for interpolation pixel to be solved.

Based on the pixel in neighborhood, the method that interpolation solves containing flag bit pixel is: based on the information of 2 × 2 neighborhood blocks taking current block as upper left hand block, as shown in Figure 2, wherein block C is current block, and R/D/RD refers to the neighborhood block in the current block left/right/top/below/upper left corner/upper right corner/lower left corner/lower right corner respectively.

If the mark place value homogeneous phase of C, R, D, RD is same, then as shown in Figure 3, carry out interpolation based on 3 × 3 Pixel Information centered by pixel to be solved in block C; Otherwise, as shown in Figure 5, carry out interpolation based on all Pixel Information in block C.

As shown in Figure 4, the process using 3 × 3 neighborhood territory pixel information of pixel to be solved in block C to carry out interpolation is: the half-tone information first based on 3 × 3 pixels calculates APL_8 and SAD_8 (APL_8 is the gray average (average pixel level) of neighborhood 8 pixels, and SAD_8 is the absolute length chang (sum ofabsolute difference) of neighborhood 8 pixels and pixel to be solved).Wherein Σ is accumulation operations symbol, g _krepresent the grey decision-making of pixel k (k=0 ~ 7), the gx grey decision-making that to be pixel to be solved hypothesis marker bit corresponding bit be after 0;

$\begin{array}{cc}\mathrm{APL}\_8=(\underset{k=0~7}{\mathrm{\Σ}}{g}_k+4)/8;& \mathrm{SAD}\_8=\underset{k=0~7}{\mathrm{\Σ}}|g_k-g_x|.\end{array}$

Then according to a predetermined threshold value Th0, the interpolation result of final pixel to be solved is determined:

$g_x^{\′}=\left\{\begin{array}{cc}{g}_x,& \mathrm{SAD}\_8>\mathrm{Th}0\\ \mathrm{APL}\_8,& \mathrm{else}\end{array}\right..$

As shown in Figure 6, use the pixel grey scale information of in block C 2 × 2, calculate APL_3 and SAD_3 (what APL_3 represented is the gray average of neighborhood 3 pixels, and SAD_3 represents the absolute length chang of neighborhood 3 pixels and pixel to be solved):

$\begin{array}{cc}\mathrm{APL}\_3=(\left(\underset{k=0~2}{\mathrm{\Σ}}{g}_k\right)*2+3)/6;& \mathrm{SAD}\_3=\underset{k=0~2}{\mathrm{\Σ}}|g_k-g_x|.\end{array}$

Then according to a predetermined threshold value Th1, the interpolation result of final pixel to be solved is determined:

$g_x^{\′}=\left\{\begin{array}{cc}{g}_x,& \mathrm{SAD}\_3>\mathrm{Th}1\\ \mathrm{APL}\_3,& \mathrm{else}\end{array}\right..$

Above specific embodiments of the invention are described.It is to be appreciated that the present invention is not limited to above-mentioned particular implementation, those skilled in the art can make various distortion or amendment within the scope of the claims, and this does not affect flesh and blood of the present invention.

Claims (8)

1., based on the method distinguishing OSD and Video signal under HDMI agreement, it is characterized in that, comprise step as follows:

1), by the signal of video signal that HDMI transmits carry out the division of block, carry out marking signal type by block;

2), service marking position carrys out the signal of video signal type that separator HDMI transmits, and Video and osd signal carried out separately process;

3), to the flag bit being used to marking signal type, utilize the pixel in neighborhood to estimate the image information that it is original.

2. the method based on distinguishing OSD and Video signal under HDMI agreement according to claim 1, it is characterized in that, described 1) specifically: the block signal of video signal that HDMI transmits being divided into M × N size, wherein, it is Video signal or osd signal that each block will mark this block by a flag bit, raising system processing speed, suppose that image size is Wd × Ht, then the value of M, N is the arbitrary value in 1 ~ Wd, 1 ~ Ht.

3. the method based on distinguishing OSD and Video signal under HDMI agreement according to claim 2, is characterized in that, the value of M, N is even number.

4. the method based on distinguishing OSD and Video signal under HDMI agreement according to claim 3, is characterized in that, M=N.

5. the method based on distinguishing OSD and Video signal under HDMI agreement according to claim 2, it is characterized in that, described 2) specifically: to each block, choose the bit i-bit of one of them pixel as flag bit, being used for marking corresponding block is Video signal or osd signal, i value 1 ~ M × N.

6. the method based on distinguishing OSD and Video signal under HDMI agreement according to claim 5, is characterized in that, i=1.

7. the method based on distinguishing OSD and Video signal under HDMI agreement according to claim 2, it is characterized in that, described 3) specifically: adopt neighborhood information to carry out the signal of video signal of recovering mark position, in signal processing, pixel component containing flag bit have lost the image information contained by itself, if do not repaired, then can reduce signal of video signal quality, utilize the pixel in its a certain size neighborhood, adopt interpolation to solve the image information of its loss, promote and recover signal of video signal quality.

8. the method based on distinguishing OSD and Video signal under HDMI agreement according to claim 7, is characterized in that, based on the contiguous range of different size, adopts different interpolation algorithms.