JP4845570B2 - Subtitle display method and digital broadcast receiver - Google Patents

Description

  The present invention relates to a caption display technique for a digital broadcast receiver.

  For example, in a vehicle navigation apparatus, there is a technology that includes means for restricting display of a building-related image when the display amount of a related image is accumulated for each building and the accumulated display amount is a predetermined amount or more ( Patent Document 1).

  Also, it is possible to display subtitles in a digital broadcast receiver. FIG. 4 is a diagram showing a typical caption display example in the digital broadcast receiver. The display screen shown in FIG. 4 displays subtitles related to today's news as an example, along with video. When the subtitle text size setting is small, the TV receiver is capable of high-speed processing, or the subtitle display is not frequently switched, the subtitle display is not burdened. be able to.

JP 2005-208158 A

  5 and 6 are diagrams illustrating an example of a caption display screen. On the screen shown in FIG. 5, a few subtitles (English characters) are displayed on the video. FIG. 6 is a diagram illustrating an example of another display screen in the same digital television receiver. As shown in FIG. 6, there are a plurality of types of subtitle display, which are displayed so as to fill the screen. When displaying a screen in which the display spreads over the entire screen or when drawing frequently occurs, there is a problem that the load becomes high, for example, the display speed of subtitles is slow.

More specifically, as shown in FIG. 7, when subtitles related to news are displayed on the display screen, the following cases may occur when processing stress (load) appears on the subtitles display. is there.
1) The character size setting is too large.
2) The display processing speed in the receiver is slow (low capability).
3) Subtitles are frequently rewritten.
4) A plurality of menus are displayed simultaneously.
In addition, as shown in FIG. 8, with current receivers, when processing stress is applied, subtitles are often displayed slowly, so that the display may be slow and annoying the viewer.

  An object of this invention is to perform subtitle display smoothly.

The present invention includes means for measuring a subtitle drawing amount and, when the drawing amount exceeds a certain threshold value, lowering the subtitle display quality (character size, scroll quality, etc.) so as not to reduce the subtitle display speed. It is characterized by that. That is, according to the display stress (drawing amount), the subtitle display setting is set in a direction in which the display stress is reduced, so that the subtitle display is not delayed.
That is, according to one aspect of the present invention, a digital television receiver capable of displaying captions, a broadcast signal acquisition unit, a load detection unit that detects a processing load, and a load detected by the load detection unit There is provided a digital television receiver comprising: a control unit that controls display quality related to subtitle display in a direction in which subtitle display speed does not decrease when a certain threshold is exceeded.

  Also, a digital television receiver capable of displaying captions, the broadcast signal acquisition unit, a load detection unit for detecting a load based on the caption service acquired from the broadcast signal acquisition unit, and detected by the load detection unit There is provided a digital television receiver comprising: a control unit that controls display quality related to caption display in a direction in which the speed of caption display does not decrease when a load exceeds a certain threshold value. Furthermore, it is preferable to have an operation unit that performs an operation of adjusting display quality related to subtitle display. By giving a width to the threshold value, it is possible to form an area where the display quality is not changed.

  According to another aspect of the present invention, there is provided a caption display method in a digital television receiver capable of displaying captions, the step of detecting a load based on a caption service acquired from a broadcast signal, and a threshold with a detected load And a step of controlling the display quality related to the subtitle display in such a direction that the subtitle display speed does not decrease.

  Regarding the subtitle display of a TV receiver, if the service provision is likely to exceed the threshold of subtitle display load, the service can be continued by adjusting the subtitle display, for example, by displaying the minimum subtitle display. . It is also possible to adjust the caption display by user operation.

  Also, receivers can be developed without being aware of differences in rendering capabilities (using the same caption rendering software, high-quality caption services for high-function receivers, and display speed for low-function receivers. Can provide a minimal subtitle service).

  Furthermore, by providing another threshold for the load, it is possible to restore the original caption display quality when the stress is reduced.

  Hereinafter, a digital television receiver according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a functional block diagram showing a configuration example of a digital television receiver according to the present embodiment. 2A and 2B are flowcharts showing the flow of processing in the digital television receiver according to the present embodiment.

  As shown in FIG. 1, the digital television receiver 1 according to the present embodiment includes a display unit 11 that displays content, a broadcast signal acquisition unit 23 that acquires broadcast signals, a screen synthesis unit 13 that combines screens, A user I / F unit 25 such as a remote control device operated by a user and a control unit 27 that performs processing for overall control are provided.

  The control unit 27 acquires the video / audio / information 21, the CC drawing information 15, and the menu drawing information 17, and based on these information, the drawing information amount (CC) 33 before screen composition, the drawing information amount after screen composition ( (Overall) 31 is detected. For example, after receiving the caption service, the caption rendering amount (number of bytes, measurement time, etc.) is measured and observed in units of time. When the subtitle rendering amount exceeds a certain threshold, the quality of the subtitle display is lowered by a method such as automatically reducing the character size, and control is performed so that the display speed does not decrease.

  For example, the ratio of the drawing information amount (CC) 33 related to subtitle display before screen composition and the drawing information amount (total) 31 after screen composition is obtained, and the ratio of the drawing information amount (CC) 33 related to subtitle display is increased. When the threshold value is exceeded, the above-described control may be performed. Alternatively, the access amount to the graphic memory may be detected. The function for obtaining such a ratio is a display stress detection function, and it can be estimated that the display stress increases as the value of the drawing information amount (CC) 33 / drawing information amount (whole) 31 increases. The detection of display stress may be left to judgment by the user's eyes.

  The drawing information increase / decrease instruction 35 may be issued from the user I / F 25. In this case, the user sees the display on the display unit 11 and performs a reaction speed detection 37 on the subtitle display. Based on this, when the detected speed is slow, the user operates in a direction to decrease the drawing information. Do.

  As shown in FIG. 2A, the subtitle display processing flow is such that, during subtitle display in step S1, the value set in step S2 depending on the ability of the drawing area digital television receiver per unit time) is a specified value. If it is above (Y), the process proceeds to step S3. Otherwise (N), the process returns to step S1. In step S3, if the response time to the user operation (almost constant regardless of the capability of the receiver) is equal to or greater than the specified value (Y), the process proceeds to step S4, the service level of subtitle display is lowered, and the process returns to step S1. If it is less than the prescribed value (N), the process returns to step S1. In other words, display stress can be detected and appropriately dealt with by steps S2 and S3.

As an example of control to lower the service level of caption display,
1) Reduce the size of characters
2) Cancel the simultaneous display of menus,
3) Reduce the number of scrolls per hour,
There are methods.

  As shown in FIG. 2B, when high-load content arrives during subtitle display (step S11) (step S12), noticeable display stress is detected (step S13). Therefore, the service level related to caption display is lowered (step S14). When the arrival of high-load content ends (step S15), a process for returning the service level related to caption display is performed (step S14).

FIG. 3A is a diagram illustrating a display example of the digital television receiver according to the present embodiment. As shown in FIG. 3A, when significant stress is detected according to the detected display stress, for example, the display quality of the caption display is lowered to a level at which display stress does not occur, and the stress related to caption display is reduced. , Maintain the display quality of content (main things such as video) Therefore, the size of characters is reduced, or menus are not displayed simultaneously.
In this way, the arrival of high load content can be dealt with.

  As shown in FIG. 3B, if the display stress is within the allowable range of the user, control is performed so as to maintain the subtitle service level without dropping the display stress until the program display is switched. Is also possible. As shown in FIG. 3B, two thresholds related to display load are provided (threshold 1, threshold 2), and if the detected load value is between threshold 1 and threshold 2, the subtitle display quality is not changed. Like that. Thereby, the unnaturalness of display due to the frequent change of quality can be eliminated. Further, the adjustment related to the display quality may be changed, for example, linearly based on the detected load value.

  As described above, the subtitle rendering amount (number of bytes, measurement time, etc.) is measured in units of time after receiving the subtitle service, and when the subtitle rendering amount exceeds a certain threshold, the subtitle display quality is lowered. By controlling so that the display speed does not decrease, there is an advantage that display stress can be reduced and subtitle display speed can be prevented from being delayed.

    The present invention can be used for a digital television receiver capable of a caption display service.

It is a functional block diagram which shows one structural example of the digital television receiver by one embodiment of this invention. It is a flowchart figure which shows the flow of a process in the digital television receiver by this Embodiment. It is a flowchart figure which shows the flow of a process in the digital television receiver by this Embodiment. It is a figure which shows the example of a display of the digital television receiver by this Embodiment. It is a modification of embodiment of this invention, Comprising: It is a figure which shows another method of determining a threshold value. It is a figure which shows the example of a general caption display in a digital broadcast receiver. It is a figure which shows an example of a caption display screen. It is a figure which shows an example of a caption display screen. It is a figure which shows the example by which the caption regarding news is displayed on the display screen. It is a figure which shows the example of a caption display in the present receiver.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Digital television receiver, 11 ... Display part, 13 ... Screen composition part, 23 ... Broadcast signal acquisition part, 25 ... User I / F part, 27 ... Control part, 31, 33 ... Display stress detection part.

Claims (5)

A digital television receiver capable of displaying subtitles,
A broadcast signal acquisition unit;
A load detection unit for detecting the load of subtitle display ;
If it exceeds a certain threshold detected load in the load detecting unit to maintain the display quality of the image, as the speed of subtitle display does not fall, and a control unit for the control of lowering the quality of the subtitle display A digital television receiver characterized by that. 2. The digital television receiver according to claim 1, wherein the control for reducing the quality of subtitle display is control for reducing the size of characters for subtitle display .   The digital television receiver according to claim 1, further comprising an operation unit that performs an operation of adjusting display quality related to subtitle display.   The digital television receiver according to any one of claims 1 to 3, wherein a region in which display quality is not changed is formed by providing a width to the threshold value. A subtitle display method in a digital television receiver capable of displaying subtitles,
Detecting the subtitle display load;
If it exceeds a certain threshold detected load, maintaining the display quality of the image, as the speed of subtitle display does not fall, subtitles, characterized in that a step of the control of lowering the quality of the subtitle display Display method.

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