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:
An image capturing optical 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 has positive refractive power. The second lens element has negative refractive power. The third lens element with refractive power has a convex object-side surface, wherein the object-side surface and an image-side surface of the third lens element are aspheric. The fourth lens element with positive refractive power has a convex object-side surface and a convex image-side surface. The fifth lens element with negative refractive power which is made of plastic material, wherein an object-side surface and an image-side surface of the fifth lens element are aspheric, and the fifth lens element has inflection points formed on at least one surface thereof.
摘要:
An image optical lens system includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element and a fourth 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 positive refractive power is made of plastic material and has a convex image-side surface, wherein an object-side surface and the image-side surface of the third lens element are aspheric. The fourth lens element with negative refractive power is made of plastic material, and has a concave object-side surface and a concave image-side surface, wherein the object-side surface and the image-side surface of the fourth lens element are aspheric, and the image-side surface of the fourth lens element changes from concave at the paraxial region to convex at the peripheral region.
摘要:
This invention provides an image lens system in order from an object side to an image side comprising: a positive first lens element with a convex object-side surface; a negative second lens element; a plastic third lens element with a concave image-side surface, both the object-side and image-side surfaces thereof being aspheric; a positive plastic fourth lens element with a convex object-side surface and a convex image-side surface, both surfaces thereof being aspheric; and a negative plastic fifth lens element with a concave image-side surface, both the object-side and image-side surfaces thereof being aspheric, at least one inflection point is formed on at least one of the two surfaces thereof; wherein there are air distances between each of lens elements. By such arrangement, not only the photosensitivity and total track length of the system can be reduced, but also better image quality can be obtained.
摘要:
The present invention provides a wide-viewing-angle imaging lens assembly comprising, in order from an object side to an image side: a front lens group, a stop, and a rear lens group. The front lens group comprises, in order from the object side to the image side: a first lens element with negative refractive power having a concave image-side surface and a second lens element. The rear lens group comprises, in order from the object side to the image side: a third lens element with positive refractive power having a concave object-side surface and a convex image-side surface, a fourth lens element with positive refractive power having a convex object-side surface and a convex image-side surface, and a fifth lens element with negative refractive power having a concave object-side surface. Such an arrangement of optical elements can effectively enlarge the field of view of the wide-viewing-angle imaging lens assembly, reduce the sensitivity of the optical system, and obtain good image quality.
摘要:
An optical lens system for image taking includes, in order from an object side to an image side, a first lens element with negative refractive power having a concave object-side surface and a concave image-side surface, a second lens element with positive refractive power having a convex image-side surface, and a third lens element with negative refractive power having a concave image-side surface of the third lens element near an optical axis and a convex image-side surface of the third lens element away from the optical axis. Both the object-side surface and the image-side surface of the third lens element are aspheric. The third lens element is made of plastic.
摘要:
A monofocal optical lens 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 refractive power, wherein at least one of the surfaces thereof is aspheric. The fourth lens element with negative refractive power is made of plastic material, and has a concave object-side surface and a convex image-side surface. The fifth lens element with refractive power is made of plastic material, and has a concave object-side surface, wherein the image-side surface thereof is convex or planar at the paraxial region and is convex at the peripheral region, and the surfaces of the fourth through fifth lens elements are aspheric.