Requirements of photo format in photography

Bmp:BMP is the abbreviation of English Bitmap, which is the standard image file format in Windows operating system and can be supported by many Windows applications. With the popularity of Windows operating system and the development of rich Windows applications, BMP bitmap format is naturally widely used. This format is characterized by rich image information and almost no compression, but this leads to its inherent defect-occupying too much disk space. So BMP is popular on stand-alone computers at present. Windows bitmap

Windows bitmaps can store a single raster image of any color depth (from black and white to 24-bit color). Windows bitmap file format is compatible with other Microsoft Windows programs. It does not support file compression, nor does it apply to web pages.

Generally speaking, the disadvantages of Windows bitmap file format outweigh the advantages. To ensure the quality of photo images, please use PNG files, JPEG files or TIFF files. BMP file is suitable for wallpaper in Windows.

Advantages: BMP supports 1 bit to 24-bit color depth.

BMP format is widely compatible with existing Windows programs (especially older programs).

Disadvantages: BMP does not support compression, which will make the file very large.

The Web browser does not support BMP files.

Jpg: It is a suffix, and jpeg can be used as both a suffix and a file format. One advantage of JPEG format is that it can compress image data. JPEG is a lossy compression format, which can compress images in a small storage space. Repeated or unimportant data in images will be lost, so it is easy to damage image data. Especially, if the compression ratio is too high, the quality of the restored image after final decompression will obviously decrease. If you pursue high-quality images, you should not use too high compression ratio. The compression ratio of JPEG is usually between 10: 1 and 40: 1. The higher the compression ratio, the lower the mass. On the contrary, the smaller the compression ratio, the better the quality. Advantages: Photographic works or realistic works support advanced compression.

The file size can be controlled by variable compression ratio.

Support interleaving (for progressive JPEG files).

JPEG widely supports Internet standards.

Disadvantages: Lossy compression will reduce the quality of the original image data.

When you edit and resave a JPEG file, JPEG will mix the quality of the original picture data. This decline is cumulative.

JPEG is not suitable for simple pictures with few colors, similar colors in a large area or obvious brightness difference.

Gif: graphic interchange format

GIF pictures store single raster image data or multiple raster image data in 8-bit colors or 256 colors. GIF pictures support transparent, compressed, interlaced and multi-image pictures (animated GIF).

Advantages:

GIF widely supports Internet standards.

Support lossless compression and transparency.

Animation GIF is very popular, and it is easy to make with many GIF animation programs.

Disadvantages:? GIF only supports a 256-color palette, so detailed pictures and realistic photographic images will lose color information, but they look tonal.

In most cases, lossless compression is not as good as JPEG format or PNG format.

GIF supports limited transparency and has no translucent effect or fading effect (such as the effect provided by alpha channel transparency).

Png: portable network graphics

PNG pictures store a single raster image at any color depth. PNG is a platform-independent format.

Advantages:

PNG supports advanced lossless compression.

PNG supports alpha channel transparency.

PNG supports gamma correction.

PNG supports interleaving.

The latest web browsers support PNG.

Disadvantages: Older browsers and programs may not support PNG files.

As an Internet file format, PNG provides less compression than JPEG lossy compression.

As an Internet file format, PNG does not support multi-image files or animation files. GIF format supports multi-image files and animation files.

Jpg format is the best, generally used for photos and pictures.