摘要:
An audio processing method is disclosed. In the audio processing method, a modified discrete cosine transform (MDCT) algorithm is utilized to transform a present time domain audio signal into a spectrum audio signal. A spreading function (SF) coefficient of each partition domain of the spectrum audio signal is obtained by referencing an SF table. A masking partitioned energy threshold of each partition domain of the spectrum audio signal is calculated utilizing a logarithmic scale. An audio block type of each partition domain and an SMR of the spectrum audio signal are calculated. Subsequently, the spectrum audio signal is compressed into an audio bit stream according to the audio block type of each partition domain and the SMR. In addition, an audio signal processing apparatus is also disclosed in this invention.
摘要:
An audio processing method is disclosed. In the audio processing method, a modified discrete cosine transform (MDCT) algorithm is utilized to transform a present time domain audio signal into a spectrum audio signal. A spreading function (SF) coefficient of each partition domain of the spectrum audio signal is obtained by referencing an SF table, wherein the table is stored in three linear arrays based on non-zero SF-Coefficient values. A masking partitioned energy threshold of each partition domain of the spectrum audio signal is calculated utilizing a logarithmic scale. An audio block type of each partition domain and an SMR of the spectrum audio signal are calculated. Subsequently, the spectrum audio signal is compressed into an audio bit stream according to the audio block type of each partition domain and the SMR. In addition, an audio signal processing apparatus is also disclosed in this invention.
摘要:
This invention provides an image capturing lens system comprising three non-cemented lens elements with refractive power: a first lens element with positive refractive power having a convex object-side surface, and both the object-side and image-side surfaces being aspheric; a plastic second lens element with negative refractive power having a concave object-side surface and a convex image-side surface, and both the object-side and image-side surfaces being aspheric; and a plastic third lens element having a convex object-side surface and a concave image-side surface, and both the object-side and image-side surfaces being aspheric. By such arrangement, the space of the image capturing lens system can be allocated much more properly and thereby an image capturing lens system with shorter total track length can be obtained while retaining superior image quality.
摘要:
An image lens system includes, in order from an object side to an image side, a first lens element with negative refractive power including a concave image-side surface; a second lens element with positive refractive power including a convex object-side surface; a third lens element with negative refractive power including an object-side surface and a concave image-side surface, the object-side surface and the image-side surface being aspheric; a fourth lens element with positive refractive power including a convex object-side surface and a convex image-side surface; and a fifth lens element with negative refractive power including a convex object-side surface and a concave image-side surface, the object-side surface and the image-side surface being aspheric, the fifth lens element having at least one inflection point.
摘要:
An image capturing system includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element. The first lens element with positive refractive power has a convex object-side surface. The second lens element has negative refractive power. The third lens element has positive refractive power. The fourth lens element with negative refractive power has a concave object-side surface and a convex image-side surface, wherein at least one of the object-side surface and the image-side surface of the fourth lens element is aspheric. The fifth lens element with refractive power has a concave image-side surface, wherein at least one of an object-side surface and the image-side surface of the fifth lens element is aspheric, and the fifth lens element has at least one inflection point on the image-side surface thereof.
摘要:
An optical imaging system includes, in order from an object side to an image side, a first lens element with a positive refractive power, a second lens element, a third lens element, a fourth lens element with a positive refractive power having an aspheric surface and a fifth lens element with a negative refractive power. An image-side surface of the fifth lens element is concave, and at least one of two surfaces of the fifth lens element is aspheric. The relationship between a sum of thicknesses of all lens elements with refractive powers on an optical axis and a distance on the optical axis between an object-side surface of the first lens element and the image-side surface of the fifth lens element in the optical imaging system can effectively reduce the total length as well as the sensitivity of the optical imaging system while gaining superior resolution.
摘要:
An image lens assembly includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element. The first lens element with positive refractive power has a convex object-side surface. The second lens element has negative refractive power. The third lens element with refractive power is made of plastic material, and has at least one surface being aspheric. The fourth lens element with refractive power is made of plastic material, and has a concave object-side surface and a convex image-side surface, wherein at least one surface of the fourth lens element is aspheric. The fifth lens element with positive refractive power is made of plastic material, and has a convex object-side surface and a convex image-side surface, wherein at least one surface of the fifth lens element is aspheric.
摘要:
This invention provides an imaging lens system in order from an object side to an image side comprising: a first lens element with positive refractive power; a plastic second lens element with negative refractive power having a concave object-side surface and a convex image-side surface, both surfaces thereof being aspheric; and a plastic third lens element with negative refractive power having a convex object-side surface and a concave image-side surface, both surfaces thereof being aspheric, and at least one inflection point is formed on at least one of the object-side and image-side surfaces thereof. Additionally, the central thickness of the second lens element is controlled favorably for the efficient spatial arrangement of the lens assembly and the simpler individual lens production while maintaining suitable thickness of the second lens element, thereby assuring image quality and improving yield rate of the product.
摘要:
This invention provides an imaging lens system in order from an object side to an image side comprising five lens elements with refractive power: a first lens element with positive refractive power having a convex object-side surface; a second lens element with negative refractive power; a plastic third lens element having at least one of the object-side and image-side surfaces thereof being aspheric; a plastic fourth lens element having a concave image side surface, at least one of the object-side and image-side surfaces thereof being aspheric; and a plastic fifth lens element having a convex object side surface and a convex image-side surface, at least one of the object-side and image-side surfaces thereof being aspheric. By such arrangement, especially with the fourth lens element having the concave image side surface, the imaging lens system can correct peripheral rays while further improving the image resolution thereof.