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Omar Elmasry
12/12/2022
Other
Computer Science OCR 1.2 Memory and Storage
Character sets, sound storage, image storage, compression, and memory types are explored in this comprehensive overview of computer data representation and storage. ASCII vs unicode comparison for character sets is discussed, along with audio sampling, image resolution, and data compression techniques. The document also covers differences between RAM and ROM, virtual memory, and data storage units.
12/12/2022
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Character sets, sound storage, image storage, compression, and memory types are explored in this comprehensive overview of computer data representation and storage. ASCII vs unicode comparison for character setsis discussed, along with audio sampling, image resolution, and data compression... Show more
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This page provides an in-depth overview of various aspects of computer data representation and storage, including character sets, sound and image storage, compression techniques, and memory types.
Character sets allow computers to understand letters, numbers, and other characters. They are logically ordered, with lower values assigned to earlier characters.
Definition: ASCII (American Standard Code for Information Interchange) is a character encoding standard that assigns unique binary codes to characters.
ASCII uses 8 bits (1 byte) per character, allowing for 256 possible characters.
Highlight: Unicode uses 2 bytes per character, accommodating languages with thousands of characters, such as Arabic.
Sound must be encoded into binary for computers to process it. This involves breaking down audio into thousands of samples per second, each stored as binary data.
Key factors in sound storage:
Sample rate: Measured in Hz, it determines how many samples are taken per second. Higher sample rates result in clearer sound but require more storage space.
Bit depth: The number of bits available for each sample. Higher bit depth improves quality but increases storage requirements.
Duration: Longer audio naturally requires more storage space.
Example: To calculate a sound file size, use the formula: file size = sample rate × duration (s) × bit depth
Images are stored as a series of pixels in binary, with each pixel represented by a specific color code.
Vocabulary: Resolution refers to the number of pixels in an image. Higher resolution results in clearer images but requires more storage space.
Color depth is the number of bits used to store the color for each pixel. Higher color depth allows for more realistic colors but increases file size.
Example: To calculate an image file size, use the formula: file size = color depth × image height (px) × image width (px)
Compression is the process of encoding data to reduce its size, thus saving storage space. There are two main types:
Lossless Compression: Compresses data without losing information, allowing for perfect reconstruction of the original data.
Lossy Compression: Reduces file size by discarding some information, resulting in smaller files but with some loss of quality.
The document discusses two primary types of computer memory:
RAM (Random Access Memory):
ROM (Read Only Memory):
Highlight: Virtual memory is simulated memory written to a file on the hard drive, allowing more applications to run than physical RAM can support.
The page also covers data storage units, binary-to-hexadecimal conversion, and factors to consider when choosing storage media, such as capacity and speed.
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This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
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iOS user
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Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
