1. teaching materials summary
Learned how conversion between binary numbers, understand the rules of computer binary addition and subtraction of positive and negative numbers.
Get some information CD, album works from the book, knowing the vector and raster graphics capabilities and their advantages and disadvantages. Know this MP3 audio format is a compression rate than other excellent formats.
2. textbook learning problems and solutions
1. lossy and lossless compression principle
Internet search to get the answer: lossy compression feature is to keep the color gradually changes, delete the sudden change colors in the image. Biology large number of experiments show that the human brain using color with the closest vicinity to fill the missing color. For example, for a white clouds on a blue sky background, lossy compression is to remove some of the color image part of the scene edge. When seen in this picture-screen, the brain will use colors on the scene saw the color to fill the missing part.
The basic principle is the same lossless compression of color information only saved once. Image compression software will first determine which areas of the image are the same and what is different. Including an image (e.g., blue) of duplicate data can be compressed, and only the sky starting and ending points need to be recorded.
2. The digital signal to an analog signal What are the advantages
Internet search was: The most important thing is to strengthen the confidentiality of communications. Speech signal after A / D conversion, may first be encrypted, then the transmission, reducing the D / A converted into an analog signal and then decrypted at the receiving end.
2. Consideration of perception
Self indeed craft, my self-learning ability is poor, feeling self-programming by checking the data is still a little difficult, progress should step up study, this habit learning mode.
3. learning progress
"Self is the craft," the fifth chapter the first three quarters, the Internet and read some vscode to use video to learn about the methods Base64 encoding and decimal numbers into single precision floating point