MJPEG Size / Compression vs MPEG-4

How big is the difference between MJPEG and MPEG-4 encoded stream? I have an IP camera capable of storing data in a 32 MB buffer, in MJPEG format or in MPEG-4. 800x600 resolution at 30 FPS Now that I was streaming MJPEG, I could save as much as 40-50 seconds. When streaming with MPEG-4, I could save 8 minutes (if there was almost no movement) and as 3 minutes if there was a lot of movement.

I know that the size of MPEG-4 depends on how many movements / changes there were, but I am interested in the fact that even with full movement, MPEG-4 can save much more video than MJPEG? Is MJPEG Compression "Bad"?

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M-JPEG isn't really that bad, it's just awesome. Encoding is widely supported, each individual frame can be decoded without reference to other data in the stream. Yes, compression ratios are not as effective as when reaching MPEG-4.

Often it is possible to set MPEG-4 streams to match the required bit rate ( CBR encodings), which is a good way to control bandwidth and actual bitrates. This is a rare JPEG-encoded option.

Check this out: MJPEG vs. H.264 with CCTV cameras (which itself is another interesting reading of Why we like MJPEG compression ).

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I do not believe that there is such a thing as a "better" or "worse" format, and newer compression methods do not add value.

It is necessary how, why the film is needed for: I was looking for a car DVR-camera and considered various compression formats. Well, you should think, what is the most important function you need? he records the MOMENT of an accident! Then, in addition to this, you can enjoy random recording of trips.

So, MJPEG will save EVERY single frame, while MPEG will encode only the difference between frames, and it may lose some details, such as the number of the car plate, or small details at the moment of impact !!

I think MJPEG is vital for such use.

But, if I use it for observation, I can tolerate the fall of the whole frame or two, and save disk space while maintaining quality

Correct me if I am wrong; I have not chosen a camera yet!

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Source: https://habr.com/ru/post/1393704/


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