摘要:
A quantization matrix adjusting method for quality improvement by scaling down the default quantization matrix. The adjusting method comprises the steps of: updating a used bits BB_X and an average quantizer scale Avg_Q; allocating a bit budget BB_C for a current picture; calculating an estimated quantizer scale EstQ_C according to the used bits BB_X, the average quantizer scale Avg_Q and the bit budget BB_C deciding the operation mode, when the estimated quantizer scale EstQ_C is smaller than a threshold Th_Q, assigning the operation mode as an adjusting mode, otherwise remaining at normal mode; scaling down a default quantization matrix as a new quantization matrix when the operation mode is the adjusting mode; and coding the current picture using the new quantization matrix and default quantization matrix in the adjusting mode and normal mode, respectively.
摘要:
An electronic device includes a display module, a base and a keyboard module. The display module is pivoted on the base. The keyboard module is disposed on the base. The keyboard module has a plurality of keys. Each of the keys includes a main body and an imprinted structure. The main body has a top surface. The imprinted structure is disposed on the top surface of the main body and includes a light guiding portion and a light scattering portion. A light emitted by the display module illuminates the keyboard module. The light is guided towards a specific direction when the light passes through the light guiding portion, and the light is scattered in other directions when the light passes through the light scattering portion.
摘要:
A quantization matrix adjusting method for avoiding underflow of VBV by enlarging the default quantization matrix. The adjusting method comprises the steps of: updating a used bits BB_X and an average quantizer scale Avg_Q; allocating the bit budget BB_C for the current picture; calculating an estimated quantizer scale EstQ_C according to the used bits BB_X, the average quantizer scale Avg_Q and the bit budget BB_C; deciding the operation mode, when the estimated quantizer scale EstQ_C is larger than a threshold Th_Q, assigning the operation mode as an alert mode, otherwise remaining at normal mode; enlarging the default quantization matrix as a new quantization matrix when the operation mode is the alert mode; and coding the current picture using the new quantization matrix and default quantization matrix in the alert mode and normal mode, respectively.
摘要:
An apparatus for constant quality rate control in moving picture compression. First, a total activity measure for the current picture to be encoded in a set of consecutive pictures is calculated. Based on the total activity measure of the current picture and an activity-to-complexity ratio of a previously encoded picture of the same type in the set of consecutive pictures, a complexity measure of the current picture is estimated. Thus, an instantaneous complexity measure is updated using the complexity measure and then an instantaneous rate is calculated. A target bit budget is allocated to the current picture depending on the instantaneous rate, the complexity measure and the instantaneous complexity measure. After encoding, the activity-to-complexity ratio for the just encoded picture is computed based on the total activity measure, actual bits consumed by the picture and the average of actual quantization step sizes used to encode the picture.
摘要:
A PWM (pulse width modulation) boost system includes a boost circuit, a voltage dividing circuit, a comparator, a PWM circuit, a pre-oscillator, and a current limit circuit. A start-up method of the PWM boost system includes (1) providing an error voltage; (2) generating a PWM signal according to the error voltage; (3) controlling a switch in a boost circuit with the PWM signal, so as to control an inductor current flowing through a boost inductor in the boost circuit; (4) charging a capacitor in the boost circuit with the inductor current, wherein charges stored in the capacitor define a DC output voltage; and (5) providing a feedback voltage according to the DC output voltage to adjust the error voltage.
摘要:
A rate control method with region of interesting support, which coding macroblocks in a current picture with different priority. The rate control method calculates a weighted macroblock activity according to the priority and a macroblock activity and a picture activity for the current picture according to the weighted macroblock activity. Then, the method allocates a bit budget for each macroblock according to the priority and calculates an estimated complexity for the current picture according to a complexity of a previously coded picture, an activity of the previously coded picture and the weighted macroblock activity. The method also calculates an estimated quantizer scale according to the estimated complexity and the bit budget, an initial virtual buffer occupancy according to an reaction factor and the estimated quantizer scale and a macroblock quantizer scale according to a virtual buffer occupancy of a previously coded macroblock, the priority and the reaction factor. The method codes each macroblock according to the macroblock quantizer scale and updates a virtual buffer occupancy of the current coded macroblock according to a used bit of the coded macroblock, the virtual buffer occupancy of the previously coded macroblock and the bit budget of current coded macroblock.
摘要:
A method and apparatus for rate control in moving picture compression. Bit allocation with initial quantization step size estimation is used at picture level. With the relationship between pre-analyzed activity of current picture to be encoded and actual complexity of previously encoded picture of the same type, a target bit budget can be allocated to the current picture in accordance with the present invention. Once the target bit budget has been determined, an initial value for an average quantization step size is estimated on the basis of the target bit budget, along with the relationship between pre-analyzed activity of current picture and actual complexity of previously coded picture. Such an initial value of the average quantization step size is useful to achieve higher picture quality at a given bit allocation.
摘要:
A semiconductor wafer includes a wafer body, a plurality of analog IC dies spacedly and alignedly formed on the wafer body to define a scribe line as a margin formed between each two dies wherein each of the dies has an internal circuit formed therewithin and at least a terminal pad formed along the scribe line, and a conductive arrangement including at least a conductive element formed on the wafer body to electrically connect the terminal pad with the internal circuit of the die in such a manner that when the die is cut off from the wafer body along the scribe line, the terminal pad is cut off from the die so as to keep the internal circuit in the die.
摘要:
A semiconductor wafer includes a wafer body, a plurality of analog IC dies spacedly and alignedly formed on the wafer body to define a scribe line as a margin formed between each two dies wherein each of the dies has an internal circuit formed therewithin and at least a terminal pad formed along the scribe line, and a conductive arrangement including at least a conductive element formed on the wafer body to electrically connect the terminal pad with the internal circuit of the die in such a manner that when the die is cut off from the wafer body along the scribe line, the terminal pad is cut off from the die so as to keep the internal circuit in the die.
摘要:
A rate control method with region of interesting support, which coding macroblocks in a current picture with different priority. The rate control method calculates a weighted macroblock activity according to the priority and a macroblock activity and a picture activity for the current picture according to the weighted macroblock activity. Then, the method allocates a bit budget for each macroblock according to the priority and calculates an estimated complexity for the current picture according to a complexity of a previously coded picture, an activity of the previously coded picture and the weighted macroblock activity. The method also calculates an estimated quantizer scale according to the estimated complexity and the bit budget, an initial virtual buffer occupancy according to an reaction factor and the estimated quantizer scale and a macroblock quantizer scale according to a virtual buffer occupancy of a previously coded macroblock, the priority and the reaction factor. The method codes each macroblock according to the macroblock quantizer scale and updates a virtual buffer occupancy of the current coded macroblock according to a used bit of the coded macroblock, the virtual buffer occupancy of the previously coded macroblock and the bit budget of current coded macroblock.