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How can the total size of all frames of a video > that video's size?
I commanded Free Video to JPG converter to convert every frame of some .mp4 into JPGs. One .mp4 of 131 MB got converted into pictures totalling 700 MB! Another .mp4 of 377 MB got converted into pictures totalling 1.0 GB!
Undeniably, these pictures all hail from the video. Thus I'm bewildered by this Emergentism! How can picture frames from a video outstrip that selfsame video itself?
2 answers
The following users marked this post as Works for me:
| User | Comment | Date |
|---|---|---|
| TextKit | (no comment) | Dec 26, 2021 at 23:33 |
Due to "compression".
The video is highly compressed. Some of that compression makes use of the picture not changing much from one frame to another. When you extracted individual frames, such compression couldn't be applied.
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The following users marked this post as Works for me:
| User | Comment | Date |
|---|---|---|
| TextKit | (no comment) | Dec 26, 2021 at 23:33 |
As already noted in another answer, the answer is compression. But it is actually much more than you might think. A typical video has a huge amount static from frame to frame. Even an "action" video (e.g., sports) will actually have only a small part change from frame to frame most of the time. In fact, if this were not the case then a single moderately sized video (e.g., YouTube) playing might require a Gigabit connection to display (e.g., 1280 x 800 x 24-bit color x 30 frames/second = 737 Megabits per second).
Keep in mind that the JPEG format itself includes significant compression. If you instead saved those images in the PNG format, you would find the same video taking many Gigabytes of storage. (The exact size will depend on resolution, color depth, frames/second and length of video.)
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