What Are Pixels?

A pixel refers to a small square of an image. These small squares have a clear position and assigned color values. The color and position of the small square determine the appearance of the image.

Pixel : refers to a smallest unit in an image represented by a sequence of numbers, called a pixel.

Instead of saying in the original entry that the image consists of points, this point is called a pixel.

Several other types of concepts, such as voxel, texel, and surfer, are derived from the idea of pixels, and they are used in other computer graphics and image processing applications.

Dots are also sometimes used to represent pixels, especially computer marketers, most of which use DPI (dots per inch).

Pixel digital camera

image

Top 8.1 million pixels

Is the most important indicator of digital cameras.

Pixels refer to the resolution of a digital camera.

It is determined by the number of photosensitive elements on the photoelectric sensor in the camera, and one photosensitive element corresponds to one pixel. Therefore, the larger the pixel, the more the photosensitive element, and the larger the corresponding cost. The image quality of digital cameras is partly determined by pixels. It is meaningless to simply compare pixels beyond a certain size. The mainstream SLR digital camera has about 10 million pixels, but ordinary photography and home 5 million pixels are sufficient because The resolution of the monitor we use is limited to 1024 × 768 to 1920 × 1200. If such a resolution is used to display a picture with too high pixels, the picture will be compressed to the size of the current screen, and some pictures will appear at this time. Sharpness is distorted. The imaging quality mainly depends on the lens of the camera, the size and quality of the photosensitive element.

The larger the pixels, the greater the resolution of the photo and the larger the printable size ^[4] . However, the early digital cameras were all below 1 million pixels. Since the second half of 1999, 2 million pixel products have gradually become the mainstream of the market. (Mobile phones are generally 2 million pixels, and ordinary digital cameras are generally above 3 million pixels.)

The current development trend of digital cameras, the pixels are like the CPU frequency of a PC, and there is an increasing momentum. In fact, from the perspective of market classification, for popular products, considering the cost-effectiveness factor, the larger the pixel, the better. After all, 2 megapixel products can already satisfy most applications of ordinary consumers.

Therefore, while most manufacturers are pursuing high-resolution digital cameras, their largest output is still aimed at popular megapixel products. The top-level dedicated camera has more than 100 million pixel-level products. In addition, consumers should note that the current digital camera products are classified into CCD pixels and software optimized pixels on the pixel nominal, the latter is much higher than the former. For example, a popular digital camera of a certain brand has 2.3 million CCD pixels and 3.3 million pixels after software optimization.

Digital camera pixels are divided into maximum pixels and effective pixels.

Maximum pixels

The English name is Maximum Pixels. The so-called maximum pixels are obtained after interpolation. The interpolation operation uses a DSP chip located inside the digital camera. When the image needs to be enlarged, the nearest interpolation method, linear interpolation and other calculation methods are used to add pixels to the image that need to be enlarged after the image is enlarged. The quality of the image obtained after the interpolation operation cannot be compared with the image of the true photosensitive imaging.

In the market, some businesses will mark "up to XXX pixels through hardware interpolation." This is the same principle, except that the image resolution of the maximum pixel is not as sharp as the effective pixel in terms of image quality and sensitivity. taking pictures.

The maximum pixel also refers directly to the pixel of the CCD / CMOS sensor. In order to increase sales, some businesses only advertise the maximum pixel of a digital camera. When the digital camera sets the picture resolution, it does take pictures with the highest pixel resolution. However, the user should be aware that this is a value obtained through the internal calculation of the digital camera, and when the picture is printed, the deterioration of the picture quality will be very obvious.

Effective Pixels

The effective pixel number English name is Effective Pixels. Unlike the maximum pixel, the effective pixel number refers to the pixel value that is actually involved in the light-sensitive imaging. The highest pixel value is the real pixel of the photosensitive device. This data usually includes the non-imaging part of the photosensitive device, and the effective pixel is the value converted at the lens zoom ratio. Taking Minolta's DiMAGE7 as an example, its CCD pixel is 5.24 million (5.24 Megapixel), because a part of the CCD does not participate in imaging, and the effective pixel is only 4.9 million.

Digital pictures are generally stored in pixels. Each pixel is the smallest unit in a digital picture. The larger the pixels, the larger the area of the picture. To increase the area of a picture, if there is no more light entering the photosensitive device, the only way is to increase the area of the pixel. This may affect the sharpness and sharpness of the picture. Therefore, with the same pixel area, the digital camera can obtain the largest picture pixel, which is the effective pixel.

When a user purchases a digital camera, he usually sees that the business advertises "maximum pixels reach XXX" and "effective pixels reach XXX", so what should users choose? When choosing a digital camera, you should pay attention to how many effective pixels the digital camera has. The value of the effective pixels is the key to determining the quality of the picture.

Pixel TV Pixel

The role of TV pixels in TV systems is:

(1) Determine the image sharpness. The smaller the pixels are, the more pixels there are in the picture and the sharper the image.

(2) Facilitate television transmission of images. The image information can be taken out point by point in a scanning manner and converted into a transferable electrical signal.

(3) Convenient for television display. No matter what form is used for image development, the image points are restored point by point by scanning.

Pixel Pixel Painting

A pixel is actually made up of many points. The "pixel painting" we are talking about here is not a dot-matrix image corresponding to a vector image, but an icon-style image. This style of image emphasizes clear outlines and bright colors. At the same time, the shape of the pixmap is often compared. Cartoon, so it is loved by many friends. The pixmap production method almost does not use the aliasing method to draw smooth lines, so it is often used in .gif format, and the pictures often appear in dynamic form. However, due to its special production process, if you change the size of the picture at will, it is difficult to style promise.

The application range of pixel painting is quite wide, from the pictures of FC home red and white machines that I played as a child to today s GBA handhelds; from black and white mobile phone pictures to today s full-color handheld computers; Pixel icons of software are everywhere. Today, pixel painting has become an art, which deeply shocks you and me.