Abstract: Provided is an image transmission apparatus in digital TV broadcasting, including: a first converter which converts added data, which are to be inserted into an image, into a pixel block; a border extender which adds an extended border area to an image area to extend the image in video data and inserts the converted added data into the extended border area; a video encoder which encodes the video data into which the border extender inserts the added data; a video decoder which decodes the video data encoded by the video encoder; and a second converter which converts the added data which are inserted as a pixel block in the video data decoded by the video decoder into original data. Accordingly, in digital TV broadcasting such as HD TV an UDTV, the added data are inserted into a hidden area, so that it is possible to transmit various types of information including contents and copyright without a deterioration in image quality.

Abstract: Provided is a video quality assessment system for digital TV. The video quality assessment system includes a video quality test signal insertion device which inserts a test signal for testing video quality into a predetermined area of a transient effect area (TEA) of each frame of a source video and a video quality measurement device which detects the test signal from a predetermined area of the video signal recovered after reception and outputs the test signal. Preferably, an insertion position of the test signal is one line or two or more lines of the TEA area which are located in a lower end portion of the video, and the test signal is configured with multi-bursts including a large number of frequencies which are in a range of DC to ½ of a sampling frequency.

Abstract: Provided is a video quality assessment system for digital TV. The video quality assessment system includes a video quality test signal insertion device which inserts a test signal for testing video quality into a predetermined area of a transient effect area (TEA) of each frame of a source video and a video quality measurement device which detects the test signal from a predetermined area of the video signal recovered after reception and outputs the test signal. Preferably, an insertion position of the test signal is one line or two or more lines of the TEA area which are located in a lower end portion of the video, and the test signal is configured with multi-bursts including a large number of frequencies which are in a range of DC to ½ of a sampling frequency.

Abstract: Provided is an image transmission apparatus in digital TV broadcasting, including: a first converter which converts added data, which are to be inserted into an image, into a pixel block; a border extender which adds an extended border area to an image area to extend the image in video data and inserts the converted added data into the extended border area; a video encoder which encodes the video data into which the border extender inserts the added data; a video decoder which decodes the video data encoded by the video encoder; and a second converter which converts the added data which are inserted as a pixel block in the video data decoded by the video decoder into original data. Accordingly, in digital TV broadcasting such as HD TV an UDTV, the added data are inserted into a hidden area, so that it is possible to transmit various types of information including contents and copyright without a deterioration in image quality.

Abstract: A mobile terminal and auto-focusing method for the same are disclosed. The auto-focusing method uses a lens position error compensation and includes: detecting a target object during a photograph mode; determining a lens position at which a focus value gradient related to the detected target object changes sign while moving a lens of the camera module in units of one step size; and performing lens position compensation by moving the lens to the found lens position. As a result, the lens position errors caused by a conventional a voice coil motor are compensated, thereby providing rapid and fine auto-focusing.

Abstract: Apparatus and a method for improving image quality in an image sensor, where a black level of a photographed image is calibrated and luminance of an image signal is expanded within the allowable range of luminance through knee correction for the image signal in which the black level is calibrated. Interpolation for restoring a dead pixel may be achieved before gamma correction for image signal.

Abstract: A lip synchronization test method for DTV receivers. The method includes the steps of: generating a digital audio stream having a frame index inserted therein and a video stream having a Transient Effect Area Test Signal (TATS) inserted therein; comparing the waveform of the time-indexed audio signal with that of the time-indexed video signal; and measuring and calculating a time difference dt between the audio and video signals based upon the time indexes of the time-indexed audio and video signals.

Abstract: An apparatus and method for auto-focusing in a mobile terminal having a camera module which can automatically photograph an image in optimum focus when the camera function is used are provided. The apparatus and method comprise detecting the subject by performing a preview mode in a camera mode; detecting and storing a focus value while moving the lens by increasing/decreasing electrical current in stages based on a focus characteristic of the detected subject, determining based on a presently-detected focus value and a previously-stored focus value if a slope has changed, and detecting an optimum focus value from a focus value at which the slope has changed; and performing a tracking mode to track a focus in a predetermined zone which includes the detected focus value at a center of the zone.

Abstract: A mobile terminal and auto-focusing method for the same are disclosed. The auto-focusing method uses a lens position error compensation and includes: detecting a target object during a photograph mode; determining a lens position at which a focus value gradient related to the detected target object changes sign while moving a lens of the camera module in units of one step size; and performing lens position compensation by moving the lens to the found lens position. As a result, the lens position errors caused by a conventional a voice coil motor are compensated, thereby providing rapid and fine auto-focusing.

Abstract: A lip synchronization test method for DTV receivers. The method includes the steps of: generating a digital audio stream having a frame index inserted therein and a video stream having a Transient Effect Area Test Signal (TATS) inserted therein; comparing the waveform of the time-indexed audio signal with that of the time-indexed video signal; and measuring and calculating a time difference dt between the audio and video signals based upon the time indexes of the time-indexed audio and video signals.

Abstract: A DTV receiver test stream generator which prevents discontinuity phenomenon of a video and an audio, a method for generating the DTV receiver test stream, and a recording medium where the DTV test stream having no discontinuity phenomenon is recorded. To this end, a test stream for a function test or a performance valuation of the DTV receiver is generated and a reproduction time is equalized on the basis of the least common multiple of a video frame time, an audio frame time, and a TS packet time when the test stream is repeatedly reproduced. According to this, when used at a DTV production field where a test pattern is used or at a broadcasting system which repeatedly transmits the DTV stream of a limited length such as a stationary image, a reliability of the DTV receiver test can be ensured.

Abstract: Apparatus and a method for improving image quality in an image sensor, where a black level of a photographed image is calibrated and luminance of an image signal is expanded within the allowable range of luminance through knee correction for the image signal in which the black level is calibrated. Interpolation for restoring a dead pixel may be achieved before gamma correction for image signal.

Abstract: An apparatus and method for auto-focusing in a mobile terminal having a camera module which can automatically photograph an image in optimum focus when the camera function is used are provided. The apparatus and method comprise detecting the subject by performing a preview mode in a camera mode; detecting and storing a focus value while moving the lens by increasing/decreasing electrical current in stages based on a focus characteristic of the detected subject, determining based on a presently-detected focus value and a previously-stored focus value if a slope has changed, and detecting an optimum focus value from a focus value at which the slope has changed; and performing a tracking mode to track a focus in a predetermined zone which includes the detected focus value at a center of the zone.

Abstract: A DTV receiver test stream generator which prevents discontinuity phenomenon of a video and an audio, a method for generating the DTV receiver test stream, and a recording medium where the DTV test stream having no discontinuity phenomenon is recorded. To this end, a test stream for a function test or a performance valuation of the DTV receiver is generated and a reproduction time is equalized on the basis of the least common multiple of a video frame time, an audio frame time, and a TS packet time when the test stream is repeatedly reproduced. According to this, when used at a DTV production field where a test pattern is used or at a broadcasting system which repeatedly transmits the DTV stream of a limited length such as a stationary image, a reliability of the DTV receiver test can be ensured.