<p>A still image doesn't have any temporal redundancy to exploit - it is a snapshot of a single point of time! Also, the quantization parameter will be low. Video compression uses higher quantization parameters since each individual frame is seen for a fraction of a second, so in a normal playback mode, the user doesn't get to focus on the details within each frame. Both of these contribute to the lower file sizes for the average image in a video.</p>

CC BY-SA 3.0
2017-12-01T05:28:49.773Z
2017-12-01T05:28:49.773Z
Gyan
<p>Photographs only have one instance in time without other related instances in time, so they can't make use of temporal redundancy because there is none.  You might be able to make some use of this for bursts of photos, but then if you separate any of the photos in the burst, you won't be able to view any of the dependent images, so it isn't very useful.</p>

<p>That said, most photos are still larger than the size of a frame in All-I frame video, but this is because the average photo has far more information.  While we tend to think of HD as high quality and UHD or 4k as even higher quality, the fact is these are image resolutions that have been on the low end of digital photography for over a decade.  A 4K image is only around the same amount of detail as an 8MP photo and an HD frame captures around 2MP.  They seem higher quality because they make use of a lot of frames playing back over time which produces a natural anti-alias effect that makes it appear higher quality, but the actual resolution of each frame is fairly low.</p>

<p>So clearly, when you compare a spatially compressed image that is a fraction of the size of another image, the smaller image ends up being a smaller file size.  The photo simply has much more information to store, even if it ends up being similarly compressed.</p>

CC BY-SA 3.0
2018-02-02T21:52:41.693Z
When you write 4:2:2 I think you mean 4:2:0, which is the color space used by most of the consumer videos as far as I know
mcont
CC BY-SA 3.0
2018-02-02T22:30:40.260Z
@MatteoContrini - could be.  At the higher end they use 4:2:2, but 4:2:0 is the same idea, just even less color detail.  I modified my answer to include both.  It's been quite a while since I shot on anything on the lower end of consumer.
AJ Henderson
CC BY-SA 3.0
2018-02-02T22:32:34.407Z
@MatteoContrini - hmm, though in investigating further about 4:2:0 vs 4:2:2 I discovered something I didn't realize about jpeg.  It actually generally uses 4:2:0 as well, so I guess that part of the answer is just wrong because jpeg does make use of it, so I'll remove the whole section.
AJ Henderson
CC BY-SA 3.0
2017-12-04T14:48:23.620Z
2018-02-02T22:31:44.433Z
2018-02-02T22:31:44.433Z
AJ Henderson
<p>I know basic video compression technique .In that it reduces spatial redundancy and temporal redundancy.If it is so why recorsing still image using camera takes more space.Why compression technique cannot remove temporal redundancy in the still image video.</p>

CC BY-SA 3.0
2017-11-30T21:37:08.153Z
What codec are you using? Something you developed yourself?
Michael Liebman
CC BY-SA 3.0
2017-12-01T05:21:17.577Z
I think it's a translation error : have --> know of
Gyan
<video-recording><signal-processing>
Why recording a still image using a mobile camera is taking up more space?
Kpullarao
# Why recording a still image using a mobile camera is taking up more space?

(Asked by: username_0 on 2017-11-30)

I know basic video compression technique .In that it reduces spatial redundancy and temporal redundancy.If it is so why recorsing still image using camera takes more space.Why compression technique cannot remove temporal redundancy in the still image video.

**Tags:** video-recording, signal-processing

> **Comments:**
> **username_1**: What codec are you using? Something you developed yourself?  
> **username_2**: I think it's a translation error : have --> know of  

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## 2 answers

### Answer by username_2 on 2017-12-01. Score: 1

A still image doesn't have any temporal redundancy to exploit - it is a snapshot of a single point of time! Also, the quantization parameter will be low. Video compression uses higher quantization parameters since each individual frame is seen for a fraction of a second, so in a normal playback mode, the user doesn't get to focus on the details within each frame. Both of these contribute to the lower file sizes for the average image in a video.


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### Answer by username_3 on 2017-12-04. Score: 0

Photographs only have one instance in time without other related instances in time, so they can't make use of temporal redundancy because there is none. You might be able to make some use of this for bursts of photos, but then if you separate any of the photos in the burst, you won't be able to view any of the dependent images, so it isn't very useful.

That said, most photos are still larger than the size of a frame in All-I frame video, but this is because the average photo has far more information. While we tend to think of HD as high quality and UHD or 4k as even higher quality, the fact is these are image resolutions that have been on the low end of digital photography for over a decade. A 4K image is only around the same amount of detail as an 8MP photo and an HD frame captures around 2MP. They seem higher quality because they make use of a lot of frames playing back over time which produces a natural anti-alias effect that makes it appear higher quality, but the actual resolution of each frame is fairly low.

So clearly, when you compare a spatially compressed image that is a fraction of the size of another image, the smaller image ends up being a smaller file size. The photo simply has much more information to store, even if it ends up being similarly compressed.

> **Comments:**
> **username_4**: When you write 4:2:2 I think you mean 4:2:0, which is the color space used by most of the consumer videos as far as I know  
> **username_3**: @MatteoContrini - could be.  At the higher end they use 4:2:2, but 4:2:0 is the same idea, just even less color detail.  I modified my answer to include both.  It's been quite a while since I shot on anything on the lower end of consumer.  
> **username_3**: @MatteoContrini - hmm, though in investigating further about 4:2:0 vs 4:2:2 I discovered something I didn't realize about jpeg.  It actually generally uses 4:2:0 as well, so I guess that part of the answer is just wrong because jpeg does make use of it, so I'll remove the whole section.  

---

