87 results about "Pre-flashing" patented technology

An auto-exposure algorithm for controlling a camera flash uses image processing to identify important areas of the image affected by the flash, while disregarding highly reflective/illuminated areas and uses a ND filter to linearize the flash triggering with highly reflective scenes. The camera flash is controlled by the auto-exposure algorithm in two stages:

a pre-flash stage followed by a main-flash stage. In the pre-flash stage, two images are captured under the same camera settings regarding the exposure time, gain, iris and resolution. One image is captured with flash and one without. From the difference between the two images, a reference pixel is used to determine the flash intensity in the main-flash stage.

An adjusting method of flash intensity is applied in an image capture apparatus with a flash lamp, where two pre-flash images corresponding the object are retrieved under two different pre-flash lights, respectively, and then a flash intensity of main-flash light is calculated according to one of the retrieved pre-flash images, so as to retrieve a main-flash image corresponding the object under the main-flash light with the calculated main-flash light.

An image sensing method and image sensing apparatus, including a subject detection unit and a flash unit, are provided. The method includes a first detection step of detecting a subject from image data obtained during preparation for main image sensing, a second detection step of detecting a subject based on reflected light data obtained during pre-flash after an instruction to begin main image sensing, a step of setting a flash illumination area based on a comparison result between a first proportion of the subject detected in the first detection step within a subject area in which the subject exists and a second proportion of the subject detected in the second detection step within the subject area, a step of calculating a flash illumination amount based on the set flash illumination area, and a step of controlling the flash unit during main image sensing based on the calculated flash illumination amount.

A method for controlling a flash of an electronic device by detecting an illumination intensity and a color temperature of a current environment from a RGB sensor. When the illumination intensity is lower than a first predetermined value, a pre-flash of the flash is turned on. Control a color temperature of the pre-flash to be equal to the color temperature when the color temperature is lower than a second predetermined value. A distance between a target object and the camera is obtained, adjusting the current of the high color temperature LED and the current of the low color temperature LED simultaneously according to the obtained distance after turning on a main-flash of the flash to capture an image of the target object.

The invention provides a photography method and system. Firstly, a first sensing image data is obtained from a surrounding light source. And then, a pre-flash is carried out by a flashlight, and a second sensing image data is obtained from the pre-flash of the flashlight. When a photography is operated, a white balance correction is carried out for each pixel in the sensing image according to the first sensing image data and the second sensing image data.

An intelligent flash system for a digital camera having components including an image optical pickup, an interface circuit, a flash unit and a processor. Upon activation of the camera, ambient lighting conditions are evaluated and if flash energy is required, a first low energy pre-flash is radiated, the reflected light received by the optical pickup having a multiplicity of pixels, and the output of the pixels converted to image intensity data by the interface circuit. The processor samples the image intensity data, weighing the center image area more heavily, and creates a histogram plot of quantity of pixels v.s. intensity, and separates the plot into a bar graph from which a determination of exposure is obtained. The histogram is then used to calculate a multiplicative scaling factor used to multiply the first flash energy to an estimate of a flash energy for correct exposure. Conditions of extreme over and under exposure result in the activation of a second flash at an adjusted energy level. The image data of the second flash is then analyzed and the exposure compared with the result of the first flash. A final determination of flash energy is then made based upon the results.

The invention provides a flash welding process of a high-strength low-magnetic anchor chain. The flash welding process is characterized in that the burn-off degree reaches 7-9 mm, the upset forging length reaches 6-8 mm, the burn-off speed reaches 1.8-2.0 mm/s, the secondary no-load voltage reaches 4.7 V, and the system pressure reaches 14-16 MPa. Compared with a conventional technological process, the flash welding process has the advantages that a pre-flash process is added, so that the problems about the rapid heat dissipation of a material and the heating of welds during low-temperature welding can be solved, the heat-affected area can be effectively enlarged, the upset forging effect can be guaranteed, and the relatively consistent shapes of welding joints can be guaranteed; sufficient upset forging pressure is exerted on welding end surfaces, gaps among the joints are rapidly reduced, the lintel blasting is stopped, liquid metal and oxide inclusion on the end surfaces are extruded, and joint areas are subjected to certain plastic deformation, so that the progress of recrystallization can be promoted, common crystal grains can be formed, and firm butt joints can be acquired; and after the upset forging is finished, the pressure of electrodes and the pressure of an upset forging oil cylinder are maintained for a certain time, and then the electrodes and the upset forging oil cylinder are cooled, so that the deformation resistance of the joints can be sufficient and welding end ports can be protected against cracking caused by ring-shaped springback.

A method for focusing by using a pre-flash is provided. The method includes the following steps. First, the image sensor captures a first image of the object, wherein the average brightness of the first image is calculated to be Y₀. Next, the image sensor captures a second image of the object with the aid of a first pre-flash having a first energy, wherein the average brightness of the second image is calculated to be Y₁. Afterwards, the image sensor captures a third image of the object with the aid of a second pre-flash having a second energy, wherein the average brightness of the third image is calculated to be Y₂. Then, the distance D to the object is calculated according to the brightness Y₀ and the difference ΔY between Y₁ and Y₂. Finally, the image sensor adjusts the focus according to the distance D.

An ultrasonic diagnostic apparatus that performs high acoustic pressure and low acoustic pressure ultrasonic transmissions by switching at predetermined timing in the enhanced ultrasonography, and displays concurrently a replenishment image obtained through the low acoustic pressure transmission in real time like a moving picture, and a pre-flash image obtained through the low acoustic pressure transmission immediately before switching to the high acoustic pressure transmission like a still image to allow the operator to understand the structure at the level of capillaries. It is also possible to display a selected image obtained through the low acoustic pressure transmission at an arbitrary timing instead of the pre-flash image.

The invention discloses a method for regulating the light sensitivity of a digital camera. The method comprises the following steps of: acquiring a live view image corresponding to a plurality of suitable targets by utilizing a shooting module; causing a flash lamp to emit preflash, and acquiring a preflah image corresponding to the suitable targets by utilizing the shooting module; calculating a reflected image according to the live view image and the preflash image; judging the presentation positions of the suitable targets in the preflash image by using the reflection information of each position on the reflected image; executing an identification program for the presentation positions to find image information presenting the suitable targets from the preflash image; judging whether the suitable targets belong to more than two depths of field or not according to the image information of the suitable targets; and when the suitable targets belong to more than two depths of field, regulating the current light sensitivity of the shooting module. By the method, relative distances among the suitable targets are judged as references by the images acquired before and after the pre-flashing of the flash lamp, and a relatively better image is acquired in the supplementary lighting state of the flash lamp.

A method for utilizing preflash of flash lamp to assist focusing includes using an image sensor to pick up an image with shot object and calculating average brightness of it, using flash lamp to carry out preflash with the first energy and using said sensor to pick up image again then calculating out average brightness of it, using flash lamp to carry out preflash with the second energy and using said sensor to pick up image then calculating out average brightness of it, using D-value of three average brightness to calculate out distance D of object to be shot.