---
title: "Frame buffer size for 1 min video"
subject: "Computer Graphics"
chapter: 1
key: "semester_5/computer_graphics:frame-buffer-1min-video"
source: https://www.bctengineer.com/q/semester_5/computer_graphics/frame-buffer-1min-video
site: BCT Engineering
---

# Frame buffer size for 1 min video

Computer Graphics · Chapter 1: Introduction and Application

- Asked in: 2076 Asoj, 4 marks; 2081 Chaitra (new course), 4 marks (asked 2 times)
- Video: [Frame buffer in computer graphics(numerical)](https://www.youtube.com/watch?v=I8MByKWmVes) — IT-TECHIEZ
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_5/computer_graphics/frame-buffer-1min-video
- Whole chapter: https://www.bctengineer.com/md/semester_5/computer_graphics/chapter-1

## Question

Calculate the frame buffer size for a raster system recording a video for 1 min with a resolution of 1280 × 1024, storing 24 bits per pixel and with a refresh rate of 25 fps.

## Short answer

Frame size = 1280×1024×24 bits = 3.75 MB. For 1 minute at 25 fps, total frames = 1500, resulting in 5.9×10^9 bytes ≈ 5.49 GB of uncompressed video storage.

## Answer

A frame buffer must hold the colour of every pixel of the frame. For a video, the total storage is the size of one frame multiplied by the number of frames.

**Given:** resolution 1280 × 1024, 24 bits/pixel, 25 fps, time = 1 min = 60 s.

```text
Pixels per frame   = 1280 × 1024            = 1,310,720
Bits per frame     = 1,310,720 × 24         = 31,457,280 bits
Bytes per frame    = 31,457,280 / 8         = 3,932,160 B = 3.75 MB
Frames in 1 minute = 25 × 60                = 1500
Total size         = 3,932,160 × 1500       = 5,898,240,000 bytes
                                            ≈ 5.49 GB (÷ 2³⁰)
```

The frame buffer for a single refreshed frame is 3.75 MB. The storage needed to hold the whole 1 minute video without compression is 5,898,240,000 bytes.

**Answer: one frame = 3.75 MB; 1 minute of video = 5.9 × 10⁹ bytes ≈ 5.49 GB.**

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. What is the size of one frame for 1280 x 1024 at 24 bits/pixel?
   A. 1.25 MB
   B. 30 MB
   C. 3.75 KB
   D. 3.75 MB (3,932,160 bytes)
   Answer: D. 1,310,720 pixels x 24 bits = 31,457,280 bits = 3,932,160 bytes. (Key point: Bits per frame)

2. How many frames are in 1 minute at 25 fps?
   A. 1500
   B. 25
   C. 60
   D. 150
   Answer: A. 25 x 60 s = 1500 frames. (Key point: Number of frames)

3. How is the total video storage found?
   A. Pixels per frame x fps only
   B. Size of one frame x number of frames
   C. Bits per pixel x seconds only
   D. Frame size / number of frames
   Answer: B. Total = frame size x number of frames. (Key point: Method)

4. What is the total size of the 1 minute video?
   A. 3,932,160 bytes
   B. 589,824,000 bytes
   C. 5,898,240,000 bytes (about 5.49 GB)
   D. 98,304,000 bytes
   Answer: C. 3,932,160 x 1500 = 5,898,240,000 bytes. (Key point: Final result)

## Related in Computer Graphics

- [Pixel access rate of raster system](https://www.bctengineer.com/question.md?key=semester_5%2Fcomputer_graphics%3Apixels-per-second-access-time) — Computer Graphics, chapter 1
- [Raster display and frame buffer load time](https://www.bctengineer.com/question.md?key=semester_5%2Fcomputer_graphics%3Araster-system-load-time) — Computer Graphics, chapter 1
- [Frame buffer for 640×480 B/W video](https://www.bctengineer.com/question.md?key=semester_5%2Fcomputer_graphics%3Aframe-buffer-bw-video-5min) — Computer Graphics, chapter 1
- [Memory for 10 minute SVGA video](https://www.bctengineer.com/question.md?key=semester_5%2Fcomputer_graphics%3Aframe-buffer-svga-10min) — Computer Graphics, chapter 1, asked 2×
- [Time to display a pixel](https://www.bctengineer.com/question.md?key=semester_5%2Fcomputer_graphics%3Atime-to-display-pixel) — Computer Graphics, chapter 1

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- [TDM frame, time slot and 24-channel system](https://www.bctengineer.com/question.md?key=semester_8%2Ftelecommunications%3Atdm-frame-24-channel) — Telecommunications, chapter 3
- [PCM bit rate for 4.5 MHz TV signal with 1024 levels](https://www.bctengineer.com/question.md?key=semester_6%2Fcommunication_systems%3Apcm-tv-4-5mhz-1024) — Communication Systems, chapter 4
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