Streaming media and adjusting bitrate

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Date:

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Quick Questions

Shade in the A or B circle for each question.

1. A video keeps pausing on a slow connection. What does an adaptive bitrate stream do?

A Lowers the bitrate so the video keeps playing smoothly

B Keeps the bitrate high and waits until the video catches up

2. Which statement about streaming services is true?

A They send compressed audio and video

B They send raw uncompressed files

3. What is buffering?

A The video being compressed again by your phone

B Playback pausing while the device waits for more data to arrive

4. Your streaming app suddenly makes the picture blurry on a weak Wi-Fi signal. Why?

A It switched to a lower bitrate automatically

B The video file was permanently damaged

5. What is the trade-off when a stream uses a lower bitrate?

A Higher quality but more buffering

B Lower quality but smoother playback

Match the Pairs

Draw a line connecting each item on the left to its match on the right.

Left column		Right column
1bitrate = 320 kbps		AA high bitrate gives better audio quality but needs a fast connection and more data
2if speed < 2: quality = "360p"		Bif data_saver: max_bitrate = 128
3Buffering happens when the data arrives slower than the video needs it to play		Cif download_speed < video_bitrate: buffering = True
4Mobile data saver mode caps the bitrate so a stream uses less of the data limit		DAutomatic quality change: the stream drops to a lower quality when the connection is slow
5if speed is slow: raise bitrate to 1080p		ERaising the bitrate on a slow connection makes buffering worse. Adaptive streaming should lower the bitrate.
6Lower bitrate = bigger file and better quality		FA lower bitrate means less data per second, so a smaller stream and lower quality, not bigger and better.

Definitions

adaptive bitrate

Fill in the Blanks

Complete each line of code by filling in the missing parts.

__ speed < 2 THEN bitrate ← 500 END IF

IF dataUsed _ dataLimit THEN bitrate ← 500 END IF

IF speed < 2 THEN bitrate _ 500 END IF

IF speed < 2 THEN bitrate ← 500 ____ bitrate ← 4000

IF _________ = TRUE THEN bitrate ← bitrate - 500 END IF

Spot the Error

Shade in the letter of the line that contains an error.

Question 1

A speed ← measure_speed()

B IF speed > 3 THEN

C bitrate ← 480

D ENDIF

Question 2

A WHILE buffer > 5

B keep loading video

C ENDWHILE

D play video

Question 3

A speed ← 1 Mbps

B IF speed < 2 THEN

C quality ← HIGH

D ENDIF

Question 4

A data_left ← 200

B WHILE data_left > 0

C stream_chunk(bitrate

D data_left ← data_left - size

E ENDWHILE

Question 5

A IF buffering = TRUE

B lower bitrate

C ENDIF

Answer Key

Streaming media and adjusting bitrate

Section A: Quick Questions

A — Lowers the bitrate so the video keeps playing smoothly

A — They send compressed audio and video

B — Playback pausing while the device waits for more data to arrive

A — It switched to a lower bitrate automatically

B — Lower quality but smoother playback

Section B: Match the Pairs

bitrate = 320 kbps → A high bitrate gives better audio quality but needs a fast connection and more data

if speed < 2: quality = "360p" → Automatic quality change: the stream drops to a lower quality when the connection is slow

Buffering happens when the data arrives slower than the video needs it to play → if download_speed < video_bitrate: buffering = True

Mobile data saver mode caps the bitrate so a stream uses less of the data limit → if data_saver: max_bitrate = 128

if speed is slow: raise bitrate to 1080p → Raising the bitrate on a slow connection makes buffering worse. Adaptive streaming should lower the bitrate.

Lower bitrate = bigger file and better quality → A lower bitrate means less data per second, so a smaller stream and lower quality, not bigger and better.

Section C: Definitions

adaptive bitrate — Streaming that lowers the bitrate of compressed audio and video on slow connections, trading quality for smooth playback with less buffering.

Section D: Fill in the Blanks

IF speed < 2 THEN
  bitrate ← 500
END IF

IF dataUsed > dataLimit THEN
  bitrate ← 500
END IF

IF speed < 2 THEN
  bitrate ← 500
END IF

IF speed < 2 THEN bitrate ← 500
ELSE bitrate ← 4000

IF buffering = TRUE THEN
  bitrate ← bitrate - 500
END IF

Section E: Spot the Error

B — The bitrate should be lowered when the connection is slow. The condition must be speed < 3. With > the bitrate drops on fast connections, not slow ones.

A — The player should keep loading while the buffer is low (buffer < 5). With > it would only load once the buffer was already full, so the video would stall.

C — A slow connection (1 Mbps is below 2) should drop to LOW quality so the video plays smoothly. Choosing HIGH would cause buffering.

C — The closing bracket is missing. The call must be stream_chunk(bitrate).

A — The IF line is missing THEN. It should be IF buffering = TRUE THEN.