The automatic camera produces. Tasks on the topic "Transmission speed, memory volume, transmission time". Good inexpensive high quality cameras

| Informatics and Information and Communication Technologies | Preparation for the USE | Control workouts

Control workouts

Part 1 Task 9.

Answers to tasks 1 - 23 are the number, sequence of letters or numbers to be recorded in Answer blank No. 1 to the right of the number of the corresponding task, starting from the first cell, without spaces, commas and other additional characters. Each character is written in a separate cell in accordance with the samples given in the form.

Example 1.

What is the minimum memory (in KB) need to be reserved so that you can save any raster image of 64 × 64 pixels in size, provided that 256 different colors can be used in the image? In response, write down only an integer, the unit of measurement is not necessary.

Example 2.

For storage arbitrary raster image The size of 1024 × 1024 pixels is assigned 512 KB of memory, while the binary number is stored for each pixel - the color code of this pixel is stored. For each pixel for storing the code, the same amount of bits is highlighted. Data compression is not performed. What maximum amount Colors can be used in the image?

Answer: ___________________________.

Example 3.

The automatic camera produces raster images of 640 × 480 pixels. In this case, the volume of the image file cannot exceed 320 KB, the data packaging is not performed. What is the maximum number of colors can be used in the palette?

All Quest Categories Finding the scope of the graphic file sound File Transmission speed

1) To store an arbitrary raster image with a size of 128 × 320 pixels, 40 Kbytes of memory is assigned without taking into account the size of the file header. To coding the color of each pixel, the same amount of bits are used, pixel codes are written to the file one by one without intervals. What is the maximum number of colors can be used in the image?

2) Automatic camera produces raster images with a size of 200 × 256 pixels. To coding the color of each pixel, the same amount of bits are used, pixel codes are written to the file one by one without intervals. The scope of the image file cannot exceed 65 Kbytes without checking the size of the file header. What is the maximum number of colors can be used in the palette?

3) Document with a volume of 40 MB can be transferred from one computer to another in two ways.

A. Squeeze the archiver, transfer the archive on the communication channel, unpack.

B. Transfer through the communication channel without the use of the archiver.

What is the faster and how much, if:  The average data transfer rate over the communication channel is 223 bits per second;  The volume of the compressed document archiver is equal to 90% of the original;  The time required for compression of the document - 16 seconds, on unpacking - 2 seconds?

In response, write the letter A, if the method is faster and, or b, if the way B. immediately after the letter empty write a number indicating how many seconds one way is faster than the other. So, for example, if the method B faster fashion And for 23 seconds, in response, you need to write B23.

Units of measurement "Seconds", "Sec.", "C" to the answer is not needed.

4) Two-channel (stereo) sound recording with a sampling frequency of 64 kHz and a 24-bit resolution. As a result, a 120 MB file was obtained, the data compression was not performed. Determine approximately how much time (in minutes) was recorded. As an answer, specify an integer, multiple 5 to the recording time.

5) Which minimum memory (in KB) must be reserved so that you can save any raster image of 64 × 64 pixels in size, provided that 256 different colors can be used in the image? In response, write down only an integer, the unit of measurement is not necessary.

6) To store an arbitrary raster image of 1024 × 1024 pixels, 512 KB of memory is assigned to the pixel, and the binary number is stored for each pixel - the color of this pixel is stored. For each pixel for storing the code, the same amount of bits is highlighted. Data compression is not performed. What is the maximum number of colors can be used in the image?

7) The musical fragment was digitized and recorded as a file without using data compression. The resulting file was transferred to the city and on the communication channel in 15 seconds. Then the same musical fragment was digitized with a resolution of 2 times higher and the sampling frequency is 1.5 times less than the first time. Data compression has not been produced. The resulting file was transferred to the city b; The bandwidth of the communication channel with the city b is 2 times higher than the communication channel with the city. How many seconds lasted the file transfer to the city b? In response, write down only an integer, the unit of measurement is not necessary.

8) Automatic camera produces raster images with a size of 640 × 480 pixels. In this case, the volume of the image file cannot exceed 320 KB, the data packaging is not performed. What is the maximum number of colors can be used in the palette?

9) The musical fragment was recorded in mono format, digitized and saved as a file without the use of data compression. The size of the received file is 24 MB. Then the same musical fragment was recorded re-in the format of stereo (two-channel record) and digitized with a resolution 4 times higher and the sampling frequency is 1.5 times less than the first time. Data compression has not been produced. Specify the file size to the MB, obtained when recording.

10) The musical fragment was digitized and recorded as a file without using data compression. The resulting file was transferred to the city and on the communication channel for 96 seconds. Then the same musical fragment was digitized with a resolution of 4 times higher and the sampling frequency is 3 times lower than the first time. Data compression has not been produced. The resulting file was transferred to the city b in 16 seconds. How many times the speed of the channel bandwidth in the city would be more channel bandwidth to the city ah?

11) The musical fragment was digitized and recorded as a file without using data compression. The resulting file was transferred to the city and on the communication channel in 45 seconds. Then the same musical fragment was digitized with a resolution 4 times lower and the sampling frequency is 12 times higher than the first time. Data compression has not been produced. The resulting file was transferred to the city b in 15 seconds. How many times the speed of the channel bandwidth in the city would be more channel bandwidth to the city ah?

HAPPY 9 TASKS OF EGE 2018 on computer science and ICT from demolism. This is the task of the basic level of complexity. An approximate time of completion of the task is 5 minutes.

Checked content elements:
- The ability to determine the speed of information transfer at a given channel bandwidth, the memory required for storing sound and graphics information.

Task 9.

Answer: ________

HAPPENING 9 TASKS EGE 2018 on computer science

The volume of the raster image is like a product of the number of pixels in the image on the amount of memory. i. needed to store the color of one pixel

In our case

640 · 480 · I ≤ 320 · 1024 · 8 BIT

i ≤ 320 · 1024 · 8 / (640 · 480),

as the bit can only be an integer, then we get

i \u003d 8. (Our task states that the scope of the image file cannot exceed 320 KB, therefore, we cannot round up! i. Round down to 8 bits!)

To do this, use the formula N \u003d 2 i

N \u003d 2 8 \u003d 256

So, in the image you can use no more 256 flowers.

. Information coding, volume and transmission of information: Demo version of the exam in computer science 2018; State graduation exam 2018; Training esmer options By computer science, thematic test tasks and tasks from the simulator on computer science 2018

✍ Show Solution:

By the formula of the image file, we have:

where N. - total number of pixels or permission, and i. - Depth of color coding (the number of bits allocated to 1 pixel)

Let's see that we are already given from the formula:

I.\u003d 320 kb, N. \u003d 640 * 420 \u003d 307200 \u003d 75 * 2 12 total pixels, i. - ?

The number of colors in the image depends on the parameter i.which is unknown. Recall the formula:

number of colors \u003d 2 i

Since the color depth is measured in bits, then the volume is necessary to translate from kilobytes to the bits:

320 KB \u003d 320 * 2 10 * 2 3 bits \u003d 320 * 2 13 bits

Find i.:

\\ [i \u003d \\ FRAC (I) (N) \u003d \\ FRAC (320 * 2 ^ (13)) (75 * 2 ^ (12)) \\ APPROX 8.5 bits \\]

We find the number of colors:

2 i \u003d 2 8 \u003d 256

Result: 256

State graduation exam of the HBE 2018 (Infi Infi Infi Infi Infi, Task 7):

Produced two-channel (Stereo) digital sound recording. The signal value is fixed 48,000 times per second, to record each value used 32 bits. Recording lasts 5 minutesThe results are recorded in a file, data compression is not performed.

Which of the following values \u200b\u200bis closest to the size of the received file?

1) 14 MB
2) 28 MB
3) 55 MB
4) 110 MB

✍ Show Solution:

I \u003d β * ƒ * T * s

Substitute the existing values \u200b\u200bin the formula:

I \u003d 48000 * 32 * 300 * 2

Since the values \u200b\u200bare large, it is necessary 48000 and 300 express in degrees of two:

48000 | 2 24000 | 2 12000 | 2 6000 | 2 = 375 * 2 7 3000 | 2 1500 | 2 750 | 2 375 | 2 - no longer divided by 187.5 300 | 2 \u003d. 75 * 2 2 150 | 2 75 | 2 - no longer divisible 37.5

We get:

I \u003d 375 * 75 * 2 15

In the proposed answer options we see that the result is everywhere in MB. So it is necessary to divide the result obtained by 2 23 (2 3 * 2 10 * 2 10):

I \u003d 375 * 75 * 2 15/2 23 \u003d 28125/2 8

Find close to the number 28125 value to degree degree:

2 10 = 1024 1024 * 2 2048 * 2 4096 * 2 8192 * 2 16384 * 2 32768

We get:

2 10 * 2 5 = 2 15 = 32768 2 10 * 2 4 = 2 14 = 16384

Number 28125 lies between these meanings, it means that we take them:

2 15 / 2 8 = 2 7 = 128 2 14 / 2 8 = 2 6 = 64

Select the answer, the value in which is between the two these numbers: option 4 (110 MB)

Result: 4

Solution 9 tasks of the EGE on computer science (diagnostic version of the examination work of 2018, S.S. Krylov, D.M. Ushakov):

Produced two-channel (stereo) sound recording with the frequency of sampling 4 kHz and 64-bit resolution. Recording lasts 1 minuteThe results are recorded in a file, data compression is not performed.

Determine approximately the size of the resulting file (in MB). As an answer, specify the nearest number, multiple to the size of the file. 2 .

✍ Show Solution:

By the formula of the audio file, we have:

I \u003d β * ƒ * T * s

I - volume β - coding depth \u003d 32 bits ƒ - sampling frequency \u003d 48000 Hz T - Time \u003d 5 min \u003d 300 s - number of channels \u003d 2

Substitute the existing values \u200b\u200bin the formula. For convenience, we will use de-degree degrees:

ƒ \u003d 4 kHz \u003d 4 * 1000 Hz ~ 2 2 * 2 10 B \u003d 64 bits \u003d 2 6/2 23 MB T \u003d 1 min \u003d 60 C \u003d 15 * 2 2 C s \u003d 2

We substitute the values \u200b\u200bin the formula of the audio file:

I \u003d 2 6 * 2 2 * 2 10 * 15 * 2 2 * 2 1/2 23 \u003d 15/4 ~ 3.75

The nearest whole, multiple two - this is the number 4

Result: 4

Solution 9 tasks of the EGE on computer science, option 1 (FII, "EGE Computer Science and ICT, standard examination options 2018", S.S. Krylov, i.e. Churkin):

The musical fragment was recorded in format quadro (four-channel entry), digitized and saved as a file without the use of data compression. The size of the file received 48 MB. Then the same musical fragment was recorded re-in format mono With sampling frequency 2 times lessthan for the first time. At the same time, when repeated recording, the playback of music was reduced 2.5 times. Data compression has not been produced.

Specify file size in MBobtained when recording. In response, write down only an integer, the unit of measurement is not necessary.

✍ Show Solution:

We write the known data on two state status - before conversion and after:

S 1 \u003d 4 channels I 1 \u003d 48 MB s 2 \u003d 1 channel ƒ 2 \u003d 1/2 ƒ 1 (two times less) T 2 \u003d 2.5 T 1 (the tempo decreased by 2.5 times)

Since the file amount changes in the same way as the time and frequency of sampling, then for the converted file we will find the volume (we take into account the number of channels):

I 2 \u003d i 1/2 * 2.5 / 4; I 2 \u003d 48/2 * 2.5 / 4 \u003d 15

Result:15