Detailed explanation of PS vector format

Suppose we write a new piece of music and give it to the record company, there are two ways:

Play the piece and record it on the tape.

Write down the score of this piece of music. The biggest difference between the two approaches is in the form of records. The former is descriptive. Contains audio information about the music. All of the information is fixed, such as playing speed, instrument timbre and so on. If you want to replace the flute with a flute, you should record it again. The latter is descriptive, does not contain audio information, and contains only a description of the melody. If you want to change the speed of playing or instrument timbre, as long as the music in the change. The dot-matrix image is descriptive and the point is the object of the record. The vector image is descriptive, and it takes the line segment and the calculation formula as the object of the record. For example, the line in the following figure, if the dot matrix to record, is from the top left corner of the first point, to the bottom right corner of the last point to record the color of all pixels. Recording this image (200x50 pixels) requires 10,000 pieces of information. Even though the line itself does not have so many pixels, the dot matrix is also a complete recording of the pixels of the entire picture. So whether it's a straight line or two or three, it's the same for dot-matrix images. is to record all the pixels in the image individually. If you use a vector to record this line, you need only three information: the line start coordinates, the line endpoint coordinates, and the line color. Use these three messages to generate images at the time of restoration, just as a band plays the music. Because of this characteristic of the vector, it makes it very easy to modify. For example, to rotate the line below the graph, the dot-matrix method needs to record all the changed pixel information. and the vector map only need to change the starting point and the end of the coordinates is good. When the image is magnified, the dot-matrix image produces blur and sawtooth. It's like a tone that accelerates when a tape is played. There is a loss to the quality of the image. The vector image is based on the enlarged coordinates to regenerate the image, does not produce blur and sawtooth. It's like the band is playing again according to the new score. There is no loss to the quality of the image.

Let's take a personal look at the difference between vector and dot matrix images after zooming in. Open in Photoshop will see the same two silhouette images, the left is the vector format, the right is the lattice format. There seems to be no difference at this point. The following figure.

The original picture size is 400x300 and now uses image _ image size to change the width to 100 pixels, and the height automatically evaluates to 75 pixels. Get the same effect as the bottom left image. At this point the two still look the same. Then use the image _ image size to change to the same 400x300 pixel as the previous one. You'll see the effect like the bottom right image. Now the difference is obvious. The right lattice format becomes blurred after the two steps above. The vector format on the left still retains the same clarity as the original. Not a little loss.

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You can also first shrink the image smaller, so that the effect of the magnification will be more obvious. The figure below is first reduced to 20x15 after the effect of amplification, the right side of the figure is "a collapse of the paste map."

Why didn't you see the difference after the first narrowing? This is because narrowing the bitmap image does not produce ambiguity, and after discarding some of the original pixels, the remaining pixels are sufficient to describe the image and do not produce a pixel vacancy. and magnified to create a pixel vacancy. Why is the vector image "weather-beaten" but still "sweat"? This is because of the previous vector image features: the memory segment coordinates to record the image. When the image is enlarged, the coordinate is enlarged and the relative position between the coordinates is not changed. The image is then regenerated based on the changed coordinates. So no amount of amplification will be distorted.

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