CN100420295C

CN100420295C - Method for using memory in time of decoding sub image frame of DVD

Info

Publication number: CN100420295C
Application number: CNB2004100531505A
Authority: CN
Inventors: 李承埈
Original assignee: Shanghai LG Electronics Co Ltd
Current assignee: Shanghai LG Electronics Co Ltd
Priority date: 2004-07-26
Filing date: 2004-07-26
Publication date: 2008-09-17
Anticipated expiration: 2024-07-26
Also published as: CN1728804A

Abstract

The present invention relates to a using method of a storing device used for DVD videos when a subsidiary picture is decoded. A scheme of the using method of a storing device when a subsidiary picture of a DVD is decoded is that: when the subsidiary picture is decoded, only under the condition that at least more than one pixel reduced value exists with no zero in a pixel of an X coordinate when a Y coordinate is n, color values and reduced values of all pixels of the X coordinate relative to the Y coordinate are stored in the storing device, and then, a Y coordinate value of an initial subsidiary picture of which the reduced value is not zero is stored so as to complete the decoding of the subsidiary picture. Besides, an SET_DAREA value is updated by using the stored Y coordinate value of the initial subsidiary picture. The effect of reducing the occupation storing space of an OSD storing device and enhancing hardware efficiency is reached by the way that pixel color and reduced values of the decoding of the subsidiary picture in a background pixel area which can not be seen by users are not stored in the storing device used for OSD.

Description

Memory using method during the decoding of DVD sprite

Technical field

The invention relates to the DVD video with the sprite decoding device, in more detail, when being exactly the sprite decoding, utilize bitmap (bitmap) characteristic of pixel data, use the invention of memory approach efficiently.

Background technology

DVD (Digital Video Disc) is as the light quantum optical disc apparatus, be have individual layer (such as, DVD5) 4.7GB, double-deck (such as, the DVD9) multimedia storage apparatus of the sound of the image of the big capacity of 8.5GB, high image quality and high tone quality.

Such DVD plays with DVD-ROM driver etc. by DVD player or PC, by hardware and software decoding device and display processing unit, and reconstructed images, voice signal is viewed and admired the user.

Up-to-date DVD player also has CD-R except the captions with common DVD, CD-RW, and the playing function of CDDA, some DVD player also have support DVD-Audio, SACD, VCD, SVCD, DVD-R, DVD ± RW, HDCD, the function of MP3.

Such DVD player is except possessing daily playing function, also support the audio stream adjustment, camera angle is adjusted, sub-picture streams adjustment etc., F.F. (fast forward), rewind down (fastreverse), (slow reverse) moved back in slow-motion (slow forward) slowly, opens and suspends (pauseon), close time-out (pause off), the trick-play functions of closing still frame (still off) and choosing arbitrarily.Also have and to climb over next chapter and the skip functions of turning over to last chapter.Simultaneously, also have various buttons and relevant user's operation (user operation) function, in user's operating function, also comprise and to select title (title), root (root), sprite (sub_picture), audio frequency, the menu function (menucall) of angle menus such as (angle).And, also have be not suitable for the controls playing function of the scene that child views and admires such as father and mother's management information (parental management information) etc.

Also have, the DVD video data stream is by big video, audio frequency, and sprite constitutes.The image of DVD video (video) compress mode is divided into MPEG-2 and MPEG-1, and image format is supported in the image format that exchanges between NTSC (National Television System Committee) and PAL (PhaseAlternating Line) mode.Under the NTSC mode, the size of image and aspect ratio are horizontal/perpendicular 720,480 pixels, 29.97Hz aspect ratio.Under the PAL mode, can have the aspect ratio of the 25Hz of 720,576 forms.And audio frequency can be stored maximum 8 audio streams, supports LinearPCM, DolbyAC-3, and mpeg audio by option, is supported DTS (Digital Theater System) even.

Sprite can have maximum 32 data flow.Sprite comprises captions (subtitle), menu, captions, Karaoke, contents such as simple cartoon.Normal use is sprite and menu in general DVD title.

Fig. 1 is made of following several parts: leading section 110 as the skeleton diagram of the general structure that shows such DVD player; DVD data processing division 120; System decoder 130; Buffer storage 140; Sprite decoder 150; OSD memory 160; OSD handling part 170; A/V decoder 180; Frequency mixer 190 and navigation manager 200.

In showing Fig. 1 that DVD constitutes, leading section 111 is as the optical instrument of common DVD machine, and control light picker 112 is physically near the CD 111 that has write down data.Promptly, light picker 112 is under the control of SERVO CONTROL portion 115, object lens (there not being mark on the figure) are placed into the light beam of light harvesting on the signal magnetic track of CD 111, reflex to signal recording surface, and then by behind the object lens light harvesting, convert the signal of telecommunication to, to RF module 113 and 115 outputs of SERVO CONTROL portion.RF module 113 has generated the RF signal of the electrical signal data of regeneration input, to preamplifier 114 outputs.Preamplifier 114 is signal digitalized with RF, increases after the amplitude, to 120 outputs of DVD data processing division.

SERVO CONTROL portion 115 becomes the focusing rub-out signal with the electrical signal conversion of input, after detecting the trail-and-error signal, light picker 112 is in order correctly to read the data of CD 111 records, and the rub-out signal of will focusing generates the focusing drive signal, the focusing transmission device in the control light picker 112; The trail-and-error signal is generated the tracking drive signal, the tracking drive device in the control light picker 112.

The DVD data of the digitized RF state that DVD data processing division 120 will physically read at leading section 111 are carried out 8/16 detection (demodulation), after error correcting (ECC) and decoding (descramble) wait, export to system decoder 130.

At this moment, CD has write down expression data (Presentation Data) and navigation data for 111 li.Expression data comprises that broadcast is to the audio frequency of picture and the sub-image data of video data and subtitle image etc.Here, expression data wraps (Pack) unit record by the PS with 2048 byte records sizes and reads, and the PS bag is made of the packet head of 14 bytes and the packet of 2034 bytes.Packet is made of the packet of record data packet head and A/V/ sprite/navigation data once more.

That is, shown in the structure of the DVD video packets of Fig. 2, packet head is by the packet start code of 4 bytes and the SCR of 6 bytes (System Clock Reference), the program mux_late of 3 bytes, and the stuffing_length of 1 byte forms.

Such as, the formation of sprite bag, as shown in Figure 2, by the packet head of 14 bytes with represent the sub-image data bag of 2034 bytes of PES to form.

From Fig. 3, we can see the structure of sub-image data bag in the detailed sprite bag.Here, sub-image data bag (SP_PKT) be by ^*The dialogue traffic identifier of the packet header of I byte and 1 byte, and more than 1 byte, the following sub-image data of 2024 bytes constitutes.Herein, sub-image data partly demonstrates ES.And, Fig. 3's ^*I can have the value from 9 bytes to 24 bytes by the size of video data packet head.The size of packet header as shown in Figure 4, according to P-STD_buffer_scale and P-STD_buffer_size, PTS (Presentationtime-stamp), Stuffing has variable value.

At this moment, if the length of sprite bag is 2048 bytes, the length of bag is less than 2048 bytes, by in packet header, inserting filling byte (stuffing byte) or filler data bag (padding packet) being pasted the tail end of packet, make the length of bag remain 2048 bytes always.

And sub-picture unit (SPU) is made of the sprite bag of a plurality of 2048 bytes.That is, a plurality of packages that are made of 2048 bytes are closed, constituted a sub-picture unit (SPU) of forming chapter captions.At this moment, a bag can constitute a sub-picture unit, and plural bag also can constitute a sub-picture unit together.

As shown in Figure 4, sub-picture unit is by the sub-picture unit header (SPUH) and the pixel data (PXD) of 4 bytes, and sprite shows that control sequence table (SP_DCSQT) constitutes.Here, pixel data and sprite show that control sequence table (SP_DCSQT) can have maximum 26610 bytes separately.

The structure that the sub-picture unit header (SPUH) that following table 1 has shown 4 bytes is made of 2 bytes of 2 bytes of expression sub-picture unit size and display sequence list start address.

[table 1]

	Content	Byte number
	Content	Byte number	SPU_SZ	The sub-picture unit size	2 bytes
SP_DCSQT_SA	Display sequence list start address	2 bytes	SPU_SZ	The sub-picture unit size	2 bytes
SP_DCSQT_SA	Display sequence list start address	2 bytes		Amount to	4 bytes

At this moment, actual sub-picture unit as shown in Figure 5, be by in the sub-image data bag except packet header, the pure sub-image data ES of dialogue traffic identifier (sub_stream_id) constitutes.

And sprite shows that control sequence table (SP_DCSQT) is made of n+1 sprite display control sequence, and sprite display control sequence separately is 2 bytes by the expression sprite display control sequence time started; 2 bytes of representing next sprite display control sequence start address; N shows that the control command language constitutes.

And each shows that the control command language is as shown in table 2 below, has 9 kinds of inscapes.

[table 2]

Command name	Content	Coding	The extension field number
Command name	Content	Coding	The extension field number	FSTA_DSP	Set pixel data forcibly and show the time started	00H	0 byte
STA_DSP	Set pixel data and show the time started	01H	0 byte	FSTA_DSP	Set pixel data forcibly and show the time started	00H	0 byte
STA_DSP	Set pixel data and show the time started	01H	0 byte	STP_DSP	Set pixel data and show dwell time	02H	0 byte
SET_COLOR	Set the pixel data colour coding	03H	2 bytes	STP_DSP	Set pixel data and show dwell time	02H	0 byte
SET_COLOR	Set the pixel data colour coding	03H	2 bytes	SET_CONTR	Set the contrast between pixel data and the key frame	04H	2 bytes
SET_DAREA	Set the pixel data viewing area	05H	6 bytes	SET_CONTR	Set the contrast between pixel data and the key frame	04H	2 bytes
SET_DAREA	Set the pixel data viewing area	05H	6 bytes	SET_DSPXA	Set pixel data and show start address	06H	4 bytes
CHG_COLCON	Set the variation of pixel data color and contrast	07H	PCD size+2 bytes	SET_DSPXA	Set pixel data and show start address	06H	4 bytes
CHG_COLCON	Set the variation of pixel data color and contrast	07H	PCD size+2 bytes	CMD_END	Show that control command finishes	FFH	0 byte

That is, in the superincumbent table 2, FSTA_DSP of 1 byte (Forcedly set displaystart timing of pixel data) and opening that sprite shows.Closed condition is irrelevant, begins to carry out the demonstration of pixel data forcibly.The STA_DSP of 1 byte (Sets display starttimingof pixel data) is the order language that the beginning sprite shows, the STP_DSP of 1 byte (Sets displays top timing of pixel data) stops the order language that sprite shows.The SET_COLOR of 3 bytes (Sets color code of pixel data) gives the pixel colour coding, and the SET_CONTR of 3 bytes (Sets contrast between pixeldata and main picture) is an order language of adjusting the contrast between pixel data and the key frame.The SET_DAREA of 7 bytes (Sets display area of pixel data) is an order language of setting the pixel data viewing area, and the SET_DSPXA of 5 bytes (Sets display startaddress of pixel data) shows the order language that first pixel data address is set that uses.When top CHG_COLCON (Sets change of color and contrast forpixel data) is the video pictures variation, change the look of pixel and the order language of contrast, CMD_END (End of Display Control Command) shows to show that the control command language finishes.

On the other hand, system decoder 130 is separated into and expresses flow data and navigation flow data in multipleization of DVD data field of DVD data processing division 120 with output.After top expression flow data is separated into audio/video/sub-picture streams data respectively once more, with the A/V flow data that separates to 180 outputs of A/V decoder, the sub-picture streams data by buffer storage 140 to 150 outputs of sprite decoder.At this moment, the flow data that will navigate is input in the navigation manager 200, navigation manager 200 and SERVO CONTROL portion 115 interlocks, whole flow processs that control DVD plays.The A/V flow data of 180 pairs of inputs of A/V decoder uses relevant decoding algorithm, finish symbolism respectively after, to frequency mixer 190 outputs.Here, buffer storage 140 can be the field that the sub-image data on the SDRAM distributes, and also can be the buffer storage of temporarily storing sub-image data.

If top sprite decoder 150 is software sprite decoders, when sprite decoder 150 produces interrupt signal at system decoder 130, after buffer storage 140 reads sub-image data and decodes, store in OSD (the On Screen Display) memory 160.The sub-image data that 170 pairs of OSD handling parts are stored in the OSD memory 160 carries out the OSD processing, to frequency mixer 190 outputs.Frequency mixer 190 will be in A/V decoder 180 after the vision signal and OSD handles in OSD handling part 170 sprite signal combination of video decode, in order to show output.Here, demonstration is the demonstration of NTSC or PAL mode.The output of frequency mixer 190 is by NTSC/PAL encoder (not indicating on the figure), finishes coding.

At this moment, the pixel data type of sprite is by encoded bitmap service cycle (Runlengthcoded bitmap), and each pixel all has 2 value.Pixel data is by background (background) pixel, and pattern (pattern) pixel is focused on (emphasis) pixel-1, and (emphasis) pixel-2 constitutes emphatically, is divided into 00,01,10,11 2 matrix data values separately.

By background pixel, pattern pixel, pixel-1 is focused on pixel-2 emphatically, can access the colored pixels degree of depth (color pixel depth) of 4bpp (bits perpixel).On behalf of each pixel, this be assigned as 4 color value, can obtain a kind of tone value separately from the palette of 16 kinds of colors.And each pixel has the contrast of 16 grades.Here said contrast refers to common transparency, if be 0, represents transparent (full transparency), if 15, represent opaque (full opacity).That is, pixel data separately can be tried to achieve 1 reduced value from having from transparent to 16 contrasts (contrast) value of opaque general transparency (transparency) value.And each flows maximum 3.36Mbps the transfer rate of sprite, and sub-picture unit is 53220byte to the maximum.

Fig. 6 has shown the example that uses 150 pairs of DVD videos of sprite decoder to use the actual decoding of sprite to Fig. 9.

In Fig. 6,720 * 480th, the viewing area of NTSC (TV system with 525/60) video, background pixel zone (Background Pixel Area) is as having the part that pixel data value is 00 data bitmap, in this case, in the video field of (0～719) * (0～479), comprise (0～719) * field of (2～474).In fact, sprite has maximum 720 * 478 size.This is that the Y coordinate can be from 2 to 479 numerical value because the X coordinate of sprite can be from 0 to 719 numerical value.

Top pixel data value can be by decoding owing to picture unit header (SPUH), pixel data (Pixel Data; PXD), and sprite show that PXD (Pixel Data) part of the sub-picture unit that control sequence table constitutes obtains.

Fig. 7 is the accompanying drawing that the characteristic captions with Fig. 6 partly enlarge, and from figure, we can see by pixel data numerical value is that 01 pattern pixel and pixel data numerical value are the captions that 11 pixel-2 emphatically constitutes.

In this case, the outline portion of captions is pattern pixel, and in fact, captions partly are to constitute by focusing on pixel-2, according to the difference of coding method, can the outline portion of captions be encoded according to pixel-1 or pixel-2 emphatically emphatically.And the captions part also can or be focused on pixel-1 and encode according to pattern pixel.

And background pixel zone (Background Pixel Area) must use background pixel data (Background Pixel data) just can encode.Therefore, other pixel data also can be used in the background pixel zone, encodes.But almost the background pixel data field of most sprite all is to utilize the background pixel data to encode, and contrast number is 0 (transparent).

Fig. 8 and Fig. 9 have shown the accompanying drawing of another actual decoding DVD video with sprite.

Fig. 8 is the same with Fig. 6, and as the sprite of the DVD video of supporting ntsc video, in this case, sprite has occupied the field, (237～484) * (396～425) in 720 * 480 video fields.

Fig. 9 is the accompanying drawing of a part of the captions of expanded view 8.Therefrom, we can know sprite which pixel data is made of.

Fig. 9 is the same with Fig. 7, and the outline portion of literal is that 01 pattern pixel constitutes by pixel data value, and the word segment that is made of pixel-2 emphatically in Fig. 7 in Fig. 9, constitutes by pixel-1 emphatically.

Therefore, when sprite was carried out actual coding, color of pixel numerical value and reduced value were very important for type of pixel.

So, see Fig. 6 and Fig. 8, can therefrom find important discrepancy.Background pixel occupies the major part of 720 * 480 video fields among Fig. 6, and among Fig. 8, background pixel occupies seldom part.Under the situation of Fig. 8, form coding by high data compression rate.

When encoding as the method for Fig. 8, not only can reduce data volume, during decoding, can reduce to take the size of memory storage space.

, for the DVD title of existing region code 3, about about 50% by encoding as Fig. 8 mode, and remaining is about 50% by encoding as Fig. 6 mode.

Here, so-called region code is divided into the whole world 6 zones exactly, and in specific hardware, the DVD that only drives specific DVD headline making saves system from damage.That is, region code is according to the difference in zone, the demand and the sales volume of the DVD title of circulation managed, and be in order to protect the film industry, just stop bootlegging, illegal circulation etc. to be used.

In other words, the DVD region code is exactly in DVD player and DVD title, and the boundary in artificial zone is set, and in specific DVD player, drives the system of specific DVD title.Korea S, Taiwan, the region code in Southeast Asia is 3.Therefore, DVD player or the DVD floppy disk of buying at home is set at 3 with region code.So, can not play title from foreign country or the DVD that directly buys by the Internet.

As mentioned above, common sprite decoder 150 is irrelevant with type of pixel or reduced value, and its color value that all are relevant with the pixel data of sprite comes out all data after storing in the OSD usefulness memory 160 in screen displayed.But the user can not see that reduced value is 0 background pixel zone.

Therefore, as shown in Figure 6, after the sub-image data of whole codings that will comprise the pixel data in whole background pixels zone is decoded in sprite decoder 150, when storing in the OSD memory 160, the problem of OSD memory 160 memory spaces appears taking in a large number.

Summary of the invention

In order to solve top problem, the objective of the invention is to utilize the characteristic of the sprite that constitutes by bitmap, when providing a kind of DVD sprite to decode, can reduce the memory using method that takies the OSD memory storage space.

For achieving the above object, when sprite of the present invention was decoded, the memory using method of DVD comprised following several stages:

(a) in sprite when decoding,, in the pixel of the X coordinate when the Y coordinate is n, having an above pixel comparison value at least is not 0 pixel, the stage that all color of pixel values of the X coordinate when the Y coordinate is n and reduced value store memory into;

(b) the storage reduced value is not the stage of the Y coordinate figure of 0 initial sprite; With

(c) finish the decoding of sprite, the Y coordinate figure of the initial sprite by storage is updated in the stage that shows the value SET_DAREA of sprite position in all videos field;

Wherein the value of (a) n in the stage is since 2, n=n+1 then, and at last up to n=endY, described endY is the rearmost position of Y coordinate.

Superincumbent (a) stage comprises following several stages:

(a-1) parameter n is decided to be 2 initial phase;

All color of pixel values of X coordinate when (a-2) the Y coordinate being n store the stage of memory into;

(a-3) judge in all pixels of the X coordinate when the Y coordinate is n, whether exist reduced value be not 0 stage of pixel;

(a-4) in superincumbent (a-3), if judge in all pixels of the X coordinate when the Y coordinate is n, having a reduced value is not 0 pixel, in memory, and the stage of the reduced value of all pixels of the X coordinate when storing the Y coordinate and being n;

(a-5) in the above (a-3) in the stage if judge that the reduced value of all pixels of the X coordinate when the Y coordinate is n is 0, is that the Y coordinate that the color of pixel value of n+1 covers above-mentioned memory stores is the stage of the pixel color value of n with the Y coordinate;

Judge in all pixels of the X coordinate when the Y coordinate is n+1 (a-6) whether having a reduced value is not the stage of 0 pixel;

(a-7) superincumbent (a-6) is in the stage, if judge that the reduced value of the pixel of the X coordinate when the Y coordinate is n+1 all is 0, it is n=n+1 that n adds 1, with the Y coordinate is after the color of pixel value of n+1 covers the color of pixel value that the Y coordinate of storing in the above-mentioned memory is n, turns back to the stage in top (a-6) stage; With

(a-6) above moving repeatedly is (a-7) after the stage, if judge in whole pixels of the X coordinate when the Y coordinate is n+1, having at least one reduced value is not 0 pixel, it is n=n+1 that n is added 1, in above-mentioned memory, and the stage of all pixel comparison values of the X coordinate when storage Y coordinate is n.

Another object of the present invention by the reference accompanying drawing, is described in detail, and can grasp and understand.

In sum, during the decoding of the sprite of DVD of the present invention, memory using method, the color of pixel and the reduced value of the sprite decoding by the background pixel zone that the storage user not can't see in the OSD memory, reduce taking the OSD memory storage space, improve the efficient of hardware.

Description of drawings

Fig. 1 is the formation block diagram of the summary of common DVD player

Fig. 2 is the schematic diagram of common DVD video packets structure;

Fig. 3 is the schematic diagram of common sprite pack arrangement;

Fig. 4 is the structural representation of common sub-picture unit (SPU);

Fig. 5 is the schematic diagram of the actual formation of common sub-picture unit;

Fig. 6 is by using the sprite decoder, the schematic diagram of the example that the DVD video is decoded with sprite;

Fig. 7 is the schematic diagram that the feature captions with Fig. 6 partly enlarge;

Fig. 8 is by using the sprite decoder, the schematic diagram of another example that the DVD video is decoded with sprite;

Fig. 9 is the schematic diagram that the feature captions with Fig. 8 partly enlarge;

When Figure 10 is DVD sprite of the present invention decoding, the flow chart of memory using method;

Figure 11 is by using the sprite decoder, to the DVD video with the schematic diagram of sprite according to an actual example of decoding.

^*The explanation of accompanying drawing main mark ^*

110: leading section 111: CD

112: light picker 113:RF module

114: preamplifier 115: SERVO CONTROL portion

120:DVD data processing division 130: system decoder

140: buffer storage 150: the sprite decoder

160:OSD memory 170:OSD handling part

180:A/V decoder 190: frequency mixer

200: navigation manager

Embodiment

Below, structure and the effect to example of the present invention is illustrated with reference to the accompanying drawings, can be illustrated by more than one example at least according to the structure of the present invention of description of drawings and effect.Therefore, detailed technological thought of the present invention and core constitute and effect is not limited to this.

The present invention is the same with Fig. 6, and during sprite decoding that the pixel data of whole background field is encoded, the storage that only will have the field that storage is worth makes the use of OSD memory reach minimized in the OSD memory.That is, the present invention is the sub-image data by the field that the storage user not can't see in memory, and it is minimized to realize that the OSD memory storage space is used.

When Figure 10 is the sprite decoding of DVD of the present invention, the action flow chart of run memory using method, former state is used examples of implementation of the hardware of Fig. 1.

That is, sprite decoder 150 is with the sub-image data decoding (stage 201) of input.At this moment, because the X coordinate of sprite can be from 0 to 719 numerical value, the Y coordinate can be from 2 to 479 numerical value, and decoding is 2 o'clock according to the Y coordinate, and 0 to 719 X coordinate, Y coordinate are 3 o'clock, and 0 to 719 X coordinate carries out successively.According to such method, can be decoded to the Y coordinate is 479 always.

For this reason, at first to carry out parameter (n) is decided to be 2 initialization (stage 202) stage.This is that the Y coordinate can be from 2 to 479 value because the X coordinate of sprite can be from 0 to 719 value.Therefore, in fact, the sprite maximum can be 720 * 478.

After finishing the top stage 202, all color of pixel values of the X coordinate when the Y coordinate is n store in the OSD memory 160 (stage 203).In the stage 202,, be that all color of pixel values of 2 o'clock X coordinate are stored in OSD memory 160 with the Y coordinate because n is initialized as 2.

Here, each pixel can partly obtain by the PXD of decoding sub-picture unit, and each color of pixel value and reduced value can show that the SET_COLOR and the SET_CONTR of control command language obtain by the sprite of decoding table 2.And the value of (0～719) * (2～474) can show that the SET_DAREA of control command language partly obtains by the decoding sprite.That is, the coordinate figure of the StartX of SET_DAREA is 0, and the EndX coordinate figure is 719.And the coordinate figure of StartY is 2, and the EndY coordinate figure is 474.

Therefore, finish the top stage 203 after, confirm the reduced value of all pixels of the X coordinate when the Y coordinate is n, judging whether to exist a reduced value is not 0 pixel (stage 204).In the superincumbent stage 204,, carry out the stage 205 if the reduced value of the X coordinate pixel that judged result is the Y coordinate when being n all is 0; If judging reduced value of existence is not 0 pixel, carry out the stage 209.That is, in the pixel of all the X coordinates in a Y coordinate, not 0 pixel if a reduced value is arranged, carry out the stage 209.

Above stage 205 be that to write the Y coordinate that (overwrite) store in OSD memory 160 be on the pixel color value of n for the color of pixel value of n+1 with the Y coordinate.Such as, in the superincumbent stage 203, if supposing the Y coordinate is that 2 o'clock X coordinate color of pixel value is stored in the OSD memory 160, in the stage 205, be that to write on the Y coordinate that is stored in OSD memory 160 be on 2 o'clock the X coordinate color of pixel value for 3 o'clock X coordinate color of pixel value with the Y coordinate.

Then, judge in the pixel of the X coordinate when the Y coordinate is n+1 whether having a reduced value is not 0 pixel (stage 206).In the stage 206, if judge that the reduced value of the pixel of the X coordinate when the Y coordinate is n+1 all is 0, n added for 1 back (n=n+1) (stage 207), carried out the stage 205.Such as if in the stage 205,206, n=2 in the stage 207, behind the n=3, carries out the stage 205.

Stage 205 is that to write (overwrite) Y coordinate in being stored in OSD memory 160 be above the color of pixel value of n for the color of pixel value of n+1 with the Y coordinate.At this moment, n adds 1, equals 3, and the stage 205 is to be that to write on the Y coordinate that is stored in the OSD memory 160 be above 3 o'clock the X coordinate color of pixel value for 4 o'clock X coordinate color of pixel value with the Y coordinate.

From the stage 205 to the stage 207 be according to Figure 10 for example, move repeatedly up to n=380.As example of the invention process,, suppose that reduced value is not that the Y coordinate figure of 0 initial sprite is 381 as Figure 11.

Therefore, the process above the operation during n=380, in the stage 206, is judged in the pixel of the X coordinate when the Y coordinate is n+1 repeatedly, and reduced value is not that 0 pixel has one at least.So, carry out the stage 208, n adds 1 back (n=n+1), and promptly n=381 carries out the stage 209.At this moment, the Y coordinate of memory phase 205 is 381 X coordinate color of pixel value in OSD memory 160.

The storage reduced value is not the Y coordinate figure of 0 initial sprite in the stage 209, carries out the stage 210.That is, be example with Figure 11, storage Y coordinate figure 381.

The reduced value of all pixels of the X coordinate the when stage 210 is n with the Y coordinate stores in the OSD memory 160.That is be that all the color of pixel values and the reduced value of 381 X coordinate stores in the OSD memory 160 with n.

Then, judge whether n=m (stage 211).Here, m can be presented at the last Y coordinate of the sprite on the display, the last Y coordinate of the sprite of also can the person of being to use setting arbitrarily.

In the stage 211, if differentiate the last Y coordinate that present Y coordinate is not a sprite, n adds 1 back (stage 212), in OSD memory 160, and all color of pixel values of X coordinate and reduced value (stage 213) when storage Y coordinate is n.Then, turn back to the stage 211 again, judge whether present Y coordinate is exactly the last Y coordinate of sprite.

On the other hand, in the stage 211, be the last Y coordinate of sprite if differentiate present Y coordinate, utilize the Y coordinate of storage, upgrade the SET_DAREA value (stage 214) of existing decoding.Figure 11 is according to Figure 10 method of the present invention, the example that the sprite of Fig. 6 coding is decoded.

In Figure 11, from 720 * 480, can see the viewing area of NTSC (TV system with 525/60) video, in OSD memory 160, store Y coordinate X coordinate color of pixel value and the reduced value of from 381 to 474 (with 479).

That is, if use the existing method of Fig. 6, all numerical value of the pixel that storage is relevant with (0～719) X (2～474) in memory 160; If use the method as Figure 10, only the pixel data with (0～719) X (381～474) stores in the OSD memory 160.

At this moment, in the decode value of SET_DAREA, the StartY coordinate is updated in the stage 209 381 of storage.In fact, as shown in figure 11, on 381 positions of Y coordinate, show spolen title.If want to change the beginning of the X coordinate of sprite, the rearmost position, any one in the rearmost position of Y coordinate, the StartX of the SET_DAREA above upgrading, EndX, the numerical value of being correlated with in the EndY value just can change.That is, when utilizing OSD to show spolen title, because the SET_DAREA decision shows the position of sprite in all videos field, so, must upgrade this part.

On the other hand, the present invention is 0 color of pixel and reduced value by do not store the contrast that is in the spolen title upper part in the OSD memory, and a kind of method that can use the OSD memory effectively is provided.In fact, if the left side of spolen title, the right side, the method that downside can both use the front to set forth just can reach and reduce the effect that takies memory space in the OSD memory more.

By above-mentioned description, the related work personnel can carry out various change and modification fully in the scope that does not depart from this invention technological thought.

Therefore, the technical scope of this invention can not be confined to the detailed description on the detailed book; Must determine its technical scope according to the scope of patent application.

Claims

1. the memory using method when the DVD sprite is decoded, this method be transmit the DVD video data that in DVD, writes down and the decoding sub-image data after, memory using method during with the sprite decoding of the sprite color of pixel value of decoding and the reduced value dvd system that stores memory into, it is characterized in that it comprises following several stages:

When (a) sprite was decoded, in the pixel of the X coordinate when the Y coordinate is n, the reduced value that has an above pixel at least was not 0 pixel, the stage that all color of pixel values of the X coordinate when the Y coordinate is n and reduced value store memory into;

(c) finish the decoding of sprite, the Y coordinate figure of the initial sprite by storage in all videos field, shows the stage that the value SET_DAREA of sprite position upgrades to decision;

2. the memory using method when DVD sprite as claimed in claim 1 is decoded is characterized in that wherein (a) stage comprises following several stages:

(a-1) parameter n is decided to be 2 initial phase;

(a-5) in the above (a-3) in the stage if judge that the reduced value of all pixels of the X coordinate when the Y coordinate is n is 0, is that the Y coordinate of storing in the above-mentioned memory of the color of pixel value covering of n+1 is the stage of the color of pixel value of n with the Y coordinate;

(a-6) above moving repeatedly, (a-7) after the stage, if judge in whole pixels of the X coordinate when the Y coordinate is n+1, having at least one reduced value is not 0 pixel, it is n=n+1 that n is added 1, in above-mentioned memory, the stage of the reduced value of all pixels of the X coordinate when storage Y coordinate is n.