WO2006114021A1

WO2006114021A1 - Synchronous caption generating method and device that can be used in portable device

Info

Publication number: WO2006114021A1
Application number: PCT/CN2005/000581
Authority: WO
Inventors: Hongjun Chai; Qiwei Hu; Zhengde Cao
Original assignee: Beijing Digital Chaotex Information Technology Ltd.
Priority date: 2005-04-27
Filing date: 2005-04-27
Publication date: 2006-11-02

Abstract

A synchronous caption generating method is disclosed. The method including the following steps: generating the clock signal; looking up the caption data to be displayed on current time according to the timing information represented by the clock signal; determining the color changing state of the caption on current time according to the timing information represented by the clock signal; outputting the caption on the basis of the color changing state and the caption data; synthesizing the final image by superimposing the caption on the main image. The invention also discloses a device for implementing the above synchronous caption generating method. The method and device in the invention can be applied in displaying karaoke caption on a portable device, and involve the advantages of possessing less storage space and processing resources, simple structure and being easy to maintain.

Description

Synchronous caption generation method and device for portable device

The present invention relates to a synchronized subtitle generating method and apparatus, and more particularly to a synchronized subtitle generating method and apparatus for portable devices such as mobile phones, personal digital assistants (PDAs) and the like. Background technique

An important part of entertainment and educational multimedia content such as karaoke and MTV is the subtitles that are played simultaneously with the music being played. We refer to this subtitle as synchronized subtitles. The basic feature of synchronous subtitles is that the color of the displayed text is automatically changed sequentially at a specific time with music or image playback, thereby achieving the purpose of prompting the end user with the lyrics and the singing rhythm.

With the rapid adoption of portable devices such as mobile phones and PDAs in people's daily lives, there is a demand for displaying various multimedia contents on these devices, and programs such as karaoke and MTV are very common. Due to the limitations of battery capacity, usage time, and carrying capacity, mobile devices have the characteristics of small memory, low processing power, and small display screen, which brings new challenges for multimedia content playback and subtitle display.

Currently common subtitles are displayed in the following ways:

1) Embedded image subtitles, that is, superimposing subtitles on the original image during the production of the media content, and performing overall recording or compression encoding on the new composite image. In this method, the subtitles have been fixed in the image as part of the projection screen. Such methods are typically used in analog videotapes, VCD systems, and broadband network video content. The advantage of this method is that no additional storage device and decoding playback device are required to process the subtitles, thereby simplifying the organization of the stored data and the structure of the player, and reducing the cost of the playback device. Its limitations are also obvious: After the production is completed, you can no longer freely change the color, position, display style, etc. of the subtitles, and this method is only applicable to streaming media composed of dynamic pictures, while streaming media is relatively large. storage. In this way, the entire karaoke system must ensure that there is a large storage space, or a large enough bandwidth for storage and transmission. Video content

2) Separate image subtitles, currently mainly used in DVD systems. This method uses a separate dynamic image to store and display subtitles, so subtitles are not directly integrated into the main screen. When the player is playing, the main screen and the specified subtitles are synchronized according to the time code, and the subtitles are superimposed on the appropriate position of the main screen (generally directly below the main screen). The advantages of such a method are: the main picture can correspond to a plurality of subtitles, and the user selects different subtitles for superposition according to usage preferences or language habits, and the user can even select to superimpose and display multiple subtitles simultaneously in the picture; the subtitle position can be based on the user. Preferences or player settings for later adjustments. However, in this method, the color, display style, and the like of the subtitle are still not adjustable, the storage of the subtitle occupies a relatively large amount of additional storage space, and a separate decoding process is required to decompress and display the subtitle.

3) Separate text subtitles. This method is mainly used in the currently popular MPEG4 format compressed video media, in addition to supporting the SUB subtitle mode of a general DVD system, and also supports subtitle data recorded in a plain text format. The subtitle data format is relatively simple and consists of multiple subtitle items. Each subtitle item contains a serial number, start time, end time, and subtitle text. The subtitle item allows more than one line of subtitle text. The advantage of this method is that the subtitles are stored in plain text, which facilitates the later editing and modification, and saves storage space compared with the image mode. Meanwhile, the separation of text subtitles allows the user to specify the position, color, font of the subtitle display during playback. Style and more. However, the subtitles of this format are closely related to the encoding of the text, and cannot support subtitles mixed in multiple languages. In addition, due to the lack of control over the rhythm of the text display, this method is generally only used for subtitle display of movies or ordinary video programs, and cannot be applied to karaoke programs.

4) The special captioning machine, after the main display decoding device outputs the display signal of the main screen, uses an independent caption display device or unit, superimposes the caption on the display signal and outputs it to the final display screen. Mostly used on early special equipment. The dedicated subtitle generator makes it easy to synthesize subtitles with different content screens, and can achieve a variety of rich display effects, such as subtitle scrolling, fades, text variants, and more. However, the cost of the captioning machine is high, the flexibility is small, and the upgrade is difficult, and it is almost impossible to apply to the current mobile device.

As described above, the principles of various synchronized subtitle display devices currently in use are not applicable to Portable devices such as mobile phones and PDAs. Using one of the above methods to display subtitles on a portable device has the disadvantage of occupying excessive system resources, low data efficiency, and lack of flexibility. When the mobile multimedia content currently used, especially when using a content carrier with a small amount of data such as MMS, mobile phone vector animation, etc., there is an urgent need for a subtitle processing unit corresponding to high storage efficiency and simple and flexible processing.

SUMMARY OF THE INVENTION It is an object of the present invention to provide such a synchronized subtitle generating method and apparatus suitable for use in a portable device. Summary of the invention

In order to achieve the above object, in accordance with an aspect of the present invention, a method for generating a synchronized subtitle is provided, including the steps of: generating a clock signal; and searching for caption data to be displayed at a corresponding current time according to timing information represented by the clock signal; Determining a subtitle color change state at a current time according to timing information represented by the clock signal; outputting a subtitle based on the color change state and the searched caption data; and superimposing the main picture and the subtitle into a final picture.

The subtitle data is divided into a plurality of subtitle data items, each subtitle data item including subtitle information displayed during a period of time, and a start time and an end time at which the subtitle data is to be displayed.

The desired subtitle data item is determined in the step of finding subtitle data by judging which time period between the start time and the end time of the current data item.

The subtitle data items are sequentially stored in the order of play, and the steps of searching for subtitle data are searched one by one according to the order in which the subtitle data items are played, or are searched according to the dichotomy.

The subtitle data item also includes one or more placeholders corresponding to the length of time the character is displayed before or after each character to be displayed.

The step of determining the color change state determines a character to be color-changed by the caption based on the number of characters included in each caption data item, the start and end time of the caption data item, and the current time. The current subtitle data item is divided into two parts by the determined character that is changing color, and is displayed in different colors or patterns, respectively.

When the playback of the screen is suspended, the generation of the clock signal is suspended, and the clock signal is restored upon playback of the resume picture.

According to another aspect of the present invention, a synchronous caption generating device is provided, including: a clock signal generating device for generating a clock signal; and a searching device, configured to search for a corresponding current time according to timing information of the clock signal a caption data display device, configured to determine a caption color change state at a current time according to timing information of the clock signal, and output a caption according to the color change state and the searched caption data; and a synthesizing device, configured to The picture and the subtitle are superimposed to form a final picture.

The synchronized subtitle generating method and the device for implementing the same according to the present invention are easy to implement, have very low requirements on the storage capacity and processing capability of the system, and are currently suitable for subtitle display methods for portable device processing.

Other objects and effects of the present invention will become more apparent from the following description of the appended claims. DRAWINGS

Preferred embodiments of the present invention will now be described with reference to the accompanying drawings, in which:

1 is a block diagram showing the internal structure of a portable device according to a caption generating apparatus according to the present invention;

2 is a flow chart showing the workflow of the caption generating device according to the present invention; FIG. 3 is a view showing the use of the binary search method to find a caption data item corresponding to a certain moment in the searching step of FIG. 2, according to an embodiment of the present invention; Flow chart

4 is a flow chart showing a subtitle display and color change process according to an embodiment of the present invention;

FIG. 5 is a block diagram showing the structure of a caption generating apparatus according to an embodiment of the present invention. detailed description Fig. 1 shows a block diagram of an internal structure of a portable device according to a caption generating apparatus according to the present invention. As shown in FIG. 1, a mobile terminal 10 as a portable device includes a user input device 101, a system timer 102, a media playback device 103, an audiovisual decoder 104, a sound device 105, a caption generator 106, and a graphic and character output device. Interface 107.

The user can control the operation of the media playback device 103 by inputting various control commands (e.g., stop playback, pause playback, resume playback, and shuffle commands, etc.) through the user input device 101. The media playback device 103 also transmits the command to the subtitle generator 106 in accordance with an instruction from the user input device 101 to operate in synchronization with the media playback device 103. The system timer 102 generates a clock signal that is simultaneously supplied to the media playback device 103 and the subtitle generator 106 for timing and synchronization. The media playback device 103 supplies the encoded image and sound data to the image sound decoder 104 for decoding processing in accordance with a user instruction. The sound signal generated by the decoding by the image sound decoder 104 is supplied to the sound device 105, and the generated image signal is supplied to the graphic and character output device interface 107. The subtitle generator 106 generates subtitle information to be currently displayed based on an instruction from the media playback device 103 and a clock signal from the system timer 102, and outputs to the graphics and character output device interface 107, wherein the subtitle information includes the text of the currently displayed subtitle Information on the discoloration of information and subtitles. The graphic and character output device interface 107 synthesizes the main image from the image sound decoder 104 and the subtitle information from the subtitle generator 106 into a final output composite image, and displays it.

In most cases, the displayed synchronized subtitles meet the following requirements:

1) The same screen can display multiple lines of subtitles, and at the same time handle the discoloration of at least one line of subtitles;

2) The rhythm of the subtitle display conforms to the beat of the corresponding music, and the length of the character discoloration interval should be an integer multiple of a basic beat;

3) Due to the limitation of human visual and auditory recognition capabilities and the processing power of portable devices, the synchronization error of subtitle display is generally allowed to be within plus or minus 1/10 seconds.

In the present invention, the caption data is stored in a separate data unit in the portable device independent of the picture content. In order to process karaoke subtitles satisfying the above conditions, in the present invention The storage of subtitle data involves the following data elements: '

1) Subtitle text body

In the present invention, taking the karaoke lyrics as an example, each line of lyrics is stored as a data item. In order to facilitate portable device processing and compatibility with multi-language encoding, subtitle text is adopted.

Unicode form storage. Depending on the processing power of the portable device and the subtitle language characteristics that need to be displayed, you can choose to use UTF-16 (16-bit Unicode encoding), or UTF-8 (8-bit Unicode encoding). For example, when recording plain English text, use UTF-8 encoding; when recording Chinese or Chinese-English mixed text, use UTF-16 encoding.

2) Subtitle start time and end time associated with the data item of the caption text body In order to save storage space, the time is the relative time of time 0 point when playing from the corresponding music.

3) The default color of the subtitle associated with the data item of the caption text body

This includes the color before the subtitle is not discolored and the color after the discoloration. The specific implementation of the present invention can expand the use of other related data, such as the color of the text border, the display effect of the text, and the like.

A flow chart of a method in accordance with the present invention is described below with reference to FIG.

In order to implement the basic caption display function, the method of the present invention comprises the steps of: initializing the caption generator 106 while the music corresponding to the caption starts playing. The caption generator 106 accepts and analyzes subtitle data, separates each subtitle data item, initializes the system timer 102, and initializes a character generator (not shown). In current mobile devices, character generators are typically composed of a font library, a coded information table, a dot matrix renderer, and corresponding interfaces.

The system timer 102 generates a uniform clock signal having an interval of less than 1 / 10 seconds after initialization (step S201). On some types of portable devices, this limit can be relaxed appropriately, but should not be greater than the maximum caption synchronization error allowed by the media content. Each clock signal of the clock is input to the subtitle generator 106, driving the drawing and color changing operations of the subtitles at the current time.

After receiving the clock signal, the subtitle generator 106 searches for the subtitle data item that should currently be displayed based on the time from the start of the music playback to the current elapsed time (step S202). Assumed sound The time reading of the music playback start time is t0, the current time reading is tx, and the start time of the subtitle data item is ts, and the end time is te, then a subtitle data item should be found to satisfy the condition ts (tx-t0) Te. Under normal conditions, subtitle data items that satisfy this condition are unique. In order to simplify the operation in the mobile device, the caption generator 106 can select the first caption data item that matches this condition, ignoring other items.

In order to improve the search efficiency in a plurality of subtitle data items, the storage order of the subtitles may be set to be consistent with the order in which the subtitles are displayed, and the order numbers starting from 0 are sequentially given to all the data items, and then the following search may be taken. Strategy:

In the case of sequential playback, the serial number of the currently played data item is recorded each time it is processed, and the recording sequence number is 0 when initializing. When the next clock signal arrives, it is judged whether the data item corresponding to the current record number meets the condition. If the condition is not met, the order determines whether the first item and the second item of data are eligible until the end of the sequence of data items. In this way, when the subtitle data itself is normal, the clock signal can meet the requirements to minimize the number of searches, and the playback process is simplified, and the system resources are less occupied.

In another preferred embodiment, the caption generator 106 is required to enable random location playback of the content in conjunction with the home screen playback device; i.e., the user can choose to implement the content at any desired location that is not predictable. In this case, since the subtitle data items have been sorted in chronological order, we can quickly find the data items that meet the requirements in an improved binary search. The specific implementation is shown in the search process shown in Figure 3. The time complexity required for this lookup is log2N, where N is the total number of data items. Using this method, when there are 1000 subtitle data items in the system (this is a large number, the total number of subtitle data items of common karaoke content does not exceed 100, including all repeated paragraphs), the number of seeks required No more than 10.

Next, the color change of the subtitle color at the current time is determined according to the current time indicated by the clock signal (step S203). In general, it is possible to judge whether the characters are discolored or not in the subtitle body text, and then output each character separately. However, this method is less efficient and can result in large amounts of data transfer and interface calls in portable device systems. In the present invention, the subtitle generator 106 performs caption color changing processing in accordance with the number of text characters of each data item and the start and end times of the data items. If the start and end of the data item The end time difference is d = te - ts, and the number of body characters of the subtitle is n, and the current time is tx. At the current moment, the number of characters that have changed color in the subtitle body is:

r = n * (tx - ts) / d

The number of characters that have not changed color is: n - r

The subtitle generator 106 divides the subtitle text into two groups according to this number, and the character generator or the graphic device transmitted to the system respectively performs character output.

The above method is only applicable to the case where the file in the subtitle is discolored at a uniform speed. In many cases, the body characters in the subtitles change color at an uneven speed, but still match the music beat. At this time, in storing the subtitle text, a placeholder character is introduced, and characters that are not commonly used in the subtitle body, such as a wavy line (~), are generally used. In different implementation schemes, the placeholder character may be selected according to the implementation. Placeholder characters participate in the calculation of the total number of characters and the number of color-changing words, but are filtered out when the output is displayed. Practice has shown that the rational use of placeholder characters can simulate the discoloration rhythm of various subtitles. Since the time at which each character in the body changes color is the pronunciation time of the character when the caption generator 106 displays the caption, the relative duration of the character's pronunciation is determined by the number of subsequent placeholder characters. If the length of a character's pronunciation is three times the basic rhythm, two placeholder characters are required after this character. The rest of the situation is like this.

Next, after determining the subtitle data item to be displayed and the discoloration state of the subtitle, the subtitle generator 106 outputs the subtitle having the determined color change state (step S204). Finally, the main picture and the subtitle are superimposed to form a final picture (step S205). This process can be invoked by calling a character generator provided by the portable device system itself, or a graphical output device. The output process of the subtitle uses the color specified in the data item. In most cases, the text of the text contained in each caption data item is output on one line. It can also be automatically wrapped at the appropriate character width based on the font size provided by the portable device and the width of the displayable area.

In another preferred embodiment, the caption generator 106 can display one or more data before or after the current caption data item in the appropriate location, depending on the content needs or user selection, or the player's request.

Figure 3 illustrates the use of a dichotomy in the lookup step of Figure 2, in accordance with one embodiment of the present invention. The search method finds a detailed flowchart of the subtitle data item corresponding to a certain moment.

As shown in FIG. 3, initialization is performed in step S301, and two parameters 1 and h are defined, where 1 represents the lower limit of the search range, and h represents the upper limit of the search range such that 1 is equal to 0 and h is equal to the end caption data item. Serial number. Note that, as described above, the serial number of the subtitle data item is consecutively numbered in the chronological order in which the subtitle data item is to be displayed. In step S302, a sequence number is obtained by calculating (1+h) 12 and taking a subtitle data item corresponding to the sequence number. Next, in step S303, since each subtitle data item includes a start time and an end time for displaying the subtitle data item, it can be determined according to the start time and the end time whether the current time tx is within the time range of the subtitle data item. . If it is within the time range of the item, the current subtitle data item is the item that should be displayed currently to be searched, thereby executing step S31 1, ending the current search process and exiting. If it is not within the time range of the item, step S304 is performed to determine whether the current time tx is less than the start time of the item. If the determination is "Yes", step S307 is executed to adjust the lower limit of the search range, that is, l=(l+h)/2+l and rounded up, so that the search range is half of the original range. If the decision at step S304 is "NO", step S305 is performed to determine whether tx is greater than the end time of the item. If the answer of step S305 is "YES", step S308 is performed to adjust the upper limit of the search range, that is, h = (l + h) / 2 and round. If the decision at step S305 is "NO", step S306 is performed to indicate that the data is erroneous, and the search flow is exited. Step S307 and step S308 both proceed to step S309 to determine whether 1 is less than 11. If the result of the determination is "YES", it indicates that the subtitle data item that should be currently played has not been found, and the process returns to step S302 to continue the above-described search process, otherwise the value of 1 is taken as the currently displayed subtitle data item.

A method for finding a current subtitle data item by a dichotomy according to an embodiment of the present invention is described in detail above, by which a desired subtitle data item can be quickly found, reducing computational complexity, and It occupies less hardware resources and is suitable for portable devices. However, it will be understood by those of ordinary skill in the art that the present invention may be practiced with a variety of conventional methods of simplification, which are included within the scope of the invention as defined by the appended claims.

Referring now to Figure 4, a caption display and color change process in accordance with one embodiment of the present invention. Figure The flow of 4 is performed after the flow of FIG. 3, and the caption data item currently to be displayed has been found before the flow of FIG. 4 is executed.

First, step S401 is executed to determine the number of characters currently discolored according to the timing information according to the method described above, thereby distinguishing the character to be discolored and the normal character not discolored in the current subtitle data item. Next, in step S402, the character to be changed is stored in the color-changing character buffer, and step S405 is executed to store the normal character that is not discolored in the normal character buffer. In the subsequent steps S403 and S406, the placeholder characters are respectively filtered out from the above two buffers, and the placeholder characters are added in advance to match the beat of the caption display as described above, so as to calculate the discoloration of the captions. Position, the placeholder character is not actually displayed. Steps S403 and S406 may also be performed while filling the corresponding character buffer, that is, steps S402 and S405. Steps S404 and S407 are respectively performed to calculate the position of the text output, and the step can be implemented by a method known in the art. Then, in step S408, the characters in the color-changing character buffer and the normal character buffer and the calculated position information are respectively output to the character output device, and the character output device outputs the color in different colors or manners according to the received information. Characters and normal characters. As the music or picture is played, or as time progresses, the number of color-changing characters changes. Therefore, in continuous display, the effect of color change in the karaoke can be obtained.

The method of processing the character discoloration described above with reference to Fig. 4 may also have other variations, for example, the placeholder character may be replaced with a time weighting value for each subtitle character. Each subtitle character to be displayed may correspond to a weighting value indicating the time at which the subtitle character is to be displayed. This also makes it possible to obtain subtitle character information that is currently changing color in a manner similar to that described above. Therefore, in addition to the flow shown in Fig. 4, there are many different ways to implement the process of subtitle discoloration.

The content and data structure of the caption data which can be employed in the present invention will be specifically described below.

According to the system structure of the currently popular portable device, the fields of the caption data are arranged as follows:

The start time and end time of the subtitle display. Use 32-bit or 16-bit binary integers Storage, if 32-bit integer storage is used, the time unit is 1880 or 1/1024 seconds; if 16-bit integer storage is used, the time unit is recommended to be 1/100 second, which can be applied to a length of 10 minutes and 55 seconds. The music meets the length requirements of most karaoke music requirements.

The normal display color of the subtitles and the color after the color change can generally be stored using 24-bit RGB values, 8-bit system-defined palette entry values, 16-bit or 8-bit RGB values, depending on the system. In some implementations, the two fields may be selectively stored or not stored due to the fixed display color, or the display color of the subtitles being customized by the later system.

Subtitle body text, Unicode encoding (UTF-16 or UTF-8), a string ending with a number 0. In some embodiments, in order to speed up the parsing, an 8-bit or 16-bit string length field can be added before the string, which requires some extra storage space.

From the efficiency of data parsing, the data field of fixed length of each data item is preferably arranged in front of the data item, and the variable length field (such as the subtitle body) appears behind the data item, so that the serial number of the data item is facilitated. Specify and manage lookups. Of course, in different implementations, the order of these data fields can be exchanged and new new data fields can be introduced. In some portable devices, multibyte data fields need to be aligned on a 2-byte boundary or a 4-byte boundary.

In order to further save storage space, the subtitle data can be separately compressed and stored using a certain compression method, or compressed and stored integrally with the main picture data. Thus, the caption generator 106 needs to call the corresponding device or interface to decompress the data before processing the caption data.

The subtitle generator 106 can use a separate clock timer or share a certain clock signal with other components of the portable device system. In this case, the portable device system or the home screen player should pass the clock signal to the caption generator 106 as soon as possible, if possible. Generally, the subtitle generator 106 displays the subtitles after the main screen is processed, so that the characters are always visibly displayed on the upper layer of the main screen. In some particular implementations, such as, but not limited to, in some vector animation players, the caption generator 106 acts as a component of the animation player and receives some time during the animation rendering process. To the clock signal, the display of such subtitles may be obscured by certain parts of the animation.

The implementation of the pause and resume play and random play functions of the caption generation method and apparatus according to the present invention will hereinafter be described.

In one embodiment of the invention, the caption generator 106 can support the pause and resume play functions of the play as needed. After the user chooses to pause the content playback, the other components of the system issue a pause signal to the caption generator 106. The system can turn off the clock signal to the caption generator 106, at which point the system should provide a separate clock count; or the system can continue to send a clock signal to the caption generator 106, which is clocked by the caption generator 106. The caption generator 106 internally sets a pause flag after receiving the pause signal, and thereafter does not process the clock signal until the recovery signal is received.

After the user resumes the playback of the screen, the system issues a resume playback signal to the subtitle generator 106. The subtitle generator 106 receives this signal, clears the internal pause flag, and continues processing and displaying the subtitle as the next clock signal arrives. In this process, attention should be paid to the processing of the time t0 at which the music starts to play. Assuming that the pause time is tp and the recovery time is tr, then the t0 value is modified to t0+tr-tp. Otherwise, if the waiting time of the pause period is not deducted, the subtitles will be out of sync when the playback resumes.

In another embodiment of the invention, the caption generator 106 can support random play as needed. The user can choose to start playing from any location that is not previously predicted by the content. In this case, the main screen and the content player should retrieve the time from the music playing device to the subtitle generator 106 at the time specified by the beginning of the music at the specified playback position. The subtitle generator 106 calculates the start time to of the playback according to the current time, the input target time, and stores it, and then searches for the subtitle data item corresponding to the target time and displays it.

In some embodiments of the invention, the system can define the actual display location of the subtitles as desired. The display position can define a reference point coordinate (pixel numerical coordinate or proportional coordinate of the display area) and define an alignment relationship of the outer rectangle of the subtitle display relative to the reference coordinate. In general, there are 9 kinds of alignments that can be used: top left alignment, left center alignment, bottom left alignment, upper middle alignment, center alignment, bottom alignment, top right alignment, right center alignment, right bottom alignment. For example, you can define the lyrics to be centered at 4/5 below the center of the screen. Display. When the subtitle is displayed, regardless of how the display width of the text changes, the subtitle generator 106 automatically calculates and adjusts the display position to achieve the center alignment effect. The system can also define other subtitle display positioning methods.

If the display position changes with time as each clock signal arrives, the effect of the word shift can be achieved. The movement of the subtitles can be pre-stored as needed for production, or calculated by a time-dependent function.

Based on the basic display mode, the caption generator 106 based on the present invention can expand other character display effects, such as hollow text, edge color enhancement, shadow, rotation, fade, etc., when the system resource permits. These effects do not change the basic subtitle display and text color rhythm control principles.

Fig. 5 shows a schematic structural view of a caption generating device 50 according to an embodiment of the present invention. The main difference between the caption generating device 50 shown in the figure and the caption generator 106 shown in FIG. 1 is that the caption generating device 50 shown in FIG. 5 further includes a clock signal generating device 501 corresponding to FIG. The system timer 102, and also includes a synthesizing device 505 for overlaying the subtitles with the main picture, which corresponds to the graphics and character output device interface 107 of FIG. Since the above two devices are included, the structure of the caption generating device shown in Fig. 5 is more independent and complete. As shown in Fig. 5, the subtitle generating apparatus includes a clock signal generating means 501, a looking means 502, a subtitle memory 503, a color change state determining means 504, and a synthesizing means 505. The clock signal generating means 501 generates a clock signal and supplies it to the finding means 502 and the color changing state determining means 504. The finding means 502 searches the caption memory 503 for the caption data item which should be displayed at the current time based on the clock signal from the clock signal generating means 501, and supplies the found caption data item to the color changing state determining means 504. The color change state determining means 504 is divided into color-changing characters and normal characters based on the clock signal from the clock signal generating means 501 and the caption data item from the search means 502, and will be displayed in different colors, respectively. The caption data item after the color change state is determined is supplied to the synthesizing device 505. The synthesizing means 505 simultaneously receives the main picture to be displayed from the present, and superimposes the subtitle which determines the discoloration state on the main picture, thereby outputting the synthesized picture and displaying it.

The subtitle generating device shown in FIG. 5 can also have other variations, such as the word in FIG. The screen memory 503 can be included in the lookup device 502, and the clock signal generated by the clock signal generating device 501 can also be provided externally by the caption generating device.

The subtitle generating method and apparatus according to the present invention have been described in detail above with reference to the accompanying drawings, but those skilled in the art will recognize that many other changes and modifications can be made without departing from the spirit and scope of the invention. It is to be understood that the invention is not limited to the specific embodiment, and the scope of the invention is defined by the appended claims.

Claims

A method for generating a synchronized subtitle, comprising the following steps:

Generating a clock signal;

And searching for the caption data to be displayed at the current moment according to the timing information represented by the clock signal;

Determining a color change state of the subtitle at the current time according to the timing information represented by the clock signal;

Outputting subtitles based on the color change state and the subtitle data found;

The main picture and the subtitle are superimposed to form a final picture.

2. The synchronized subtitle generating method according to claim 1, wherein the subtitle data is divided into a plurality of subtitle data items, each subtitle data item includes subtitle information displayed over a period of time, and the subtitle data is to be displayed. Start time and end time.

3. The synchronized subtitle generating method according to claim 2, wherein in the step of searching for subtitle data, it is determined by determining a time period between a start time and an end time of which subtitle data item the current time point falls The required subtitle data item.

4. The synchronized subtitle generating method according to claim 3, wherein the subtitle data items are sequentially stored in a play order, and the step of searching for subtitle data is searched one by one according to a sequence in which the subtitle data items are played, or according to a dichotomy Come find it.

The synchronized subtitle generating method according to claim 2, wherein the subtitle data item further includes one or more placeholders corresponding to the time length of the character display before or after each character to be displayed.

The synchronized subtitle generating method according to claim 2 or 5, wherein the step of determining a discoloration state is based on a number of characters of each subtitle data item, a start and end time of the subtitle data item, and a current time To determine the word to be subtitled

7. The synchronized subtitle generating method according to claim 6, wherein the current subtitle data item is divided into two parts by the determined character that is changing color, respectively, using different colors Or style to display.

8. The synchronized subtitle generating method according to claim 1, wherein the clock signal is paused when the playback of the screen is paused, and the clock signal is restored when the playback of the screen is resumed. '

9. A synchronized subtitle generating device, comprising the following devices:

a clock signal generating device for generating a clock signal;

a searching device, configured to search, according to the timing information of the clock signal, the caption data that should be displayed at the current moment;

a color change state determining means, configured to determine a color change state of the subtitle at the current time according to the timing information of the clock signal, and output the subtitle according to the color change state and the searched caption data;

a synthesizing device, configured to superimpose the main picture and the subtitle into a final picture.

10. The synchronized subtitle generating apparatus according to claim 9, wherein the subtitle data is divided into a plurality of subtitle data items, each subtitle data item including subtitle information displayed over a period of time and a subtitle data to be displayed Start time and end time.

1 1. The synchronized subtitle generating apparatus according to claim 10, wherein said searching means determines the required time by judging which time period between the start elbow and the end time of the caption data item of the current time point Subtitle data item.

12. The synchronized subtitle generating device according to claim 1, wherein the subtitle data items are sequentially stored in a play order, and the searching device searches one by one according to a sequence in which the subtitle data items are played, or searches according to a binary method. .

13. The synchronized subtitle generating apparatus according to claim 10, wherein the subtitle data item further includes one or more placeholders corresponding to the time length of the character display before or after each character to be displayed.

The synchronized subtitle generating apparatus according to claim 10 or 13, wherein the discoloration state determining means determines the number of characters included in each subtitle data item, the start and end time of the subtitle data item, and the current time. To pay for the subtitle color change

15. The synchronized subtitle generating device according to claim 14, wherein The character that is changing color divides the current subtitle data item into two parts, which are respectively displayed in different colors or styles.

16. The synchronized subtitle generating apparatus according to claim 9, wherein the clock signal generating means suspends the generation of the clock signal when the playback of the picture is paused, and restores the clock signal upon playback of the resume picture.