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Thread ID: 135227	2013-10-09 21:30:00	.jpg file sizes	skeptile2 (16539)	Press F1

Post ID	Timestamp	Content	User
1355576	2013-10-09 21:30:00	Hi everyone, I'm doing this thing for school concerning image size. Basically, what I'm wondering is why a 5 megapixel camera image (resolution of 2560x1920, a total of 4915200 pixels) which uses 24-bit colour, would have an image size of around 1.53MB(megabytes, not bits). When I did the calculations myself, I came up with a figure of around 14MB. Obviously this is wrong, otherwise I would have about -2GB space on my phone (which shoots at 5MP), but I can't figure out why I'm getting a bigger image size. I really hope I'm not making a really stupid mistake, but I can't see it myself. Any help appreciated :D Skeptile	skeptile2 (16539)
1355577	2013-10-09 22:03:00	Hi everyone, I'm doing this thing for school concerning image size. Basically, what I'm wondering is why a 5 megapixel camera image (resolution of 2560x1920, a total of 4915200 pixels) which uses 24-bit colour, would have an image size of around 1.53MB(megabytes, not bits). When I did the calculations myself, I came up with a figure of around 14MB. Obviously this is wrong, otherwise I would have about -2GB space on my phone (which shoots at 5MP), but I can't figure out why I'm getting a bigger image size. I really hope I'm not making a really stupid mistake, but I can't see it myself. Any help appreciated :D Skeptile The image file size has a lot to do with the colour information stored in each pixel. Just did a bit of googling.. you might want to check this link out www.microscope-microscope.org	Webdevguy (17166)
1355578	2013-10-09 22:03:00	jpg is a compressed image format. If your camera offered RAW image format that would be uncompressed and take the full 14.7 MB, professional cameras do this for maximum quality. Jpeg is like a zip file but specifically designed for images, try looking it up and doing your own schoolwork :P maybe a bit of research into how the compression works might earn you some brownie points.	dugimodo (138)
1355579	2013-10-09 22:08:00	Great response! :)	Webdevguy (17166)
1355580	2013-10-09 22:19:00	The image file size has a lot to do with the colour information stored in each pixel. Just did a bit of googling.. you might want to check this link out www.microscope-microscope.org Sweet thanks! The link explained a lot. jpg is a compressed image format. If your camera offered RAW image format that would be uncompressed and take the full 14.7 MB, professional cameras do this for maximum quality. Jpeg is like a zip file but specifically designed for images, try looking it up and doing your own schoolwork :P maybe a bit of research into how the compression works might earn you some brownie points. Yeah I didn't realise that the camera itself compressed the images as you took and saved them. Thanks people, I'll look it :)	skeptile2 (16539)
1355581	2013-10-09 22:21:00	On a side note, a 5MP BMP file probably would end up around 14MB as it's an uncompressed format.EDIT: Yep just tried it, my resized-from-8.7MP image ended up as a 14.3MB BMP file. :)	pcuser42 (130)
1355582	2013-10-09 22:31:00	RAW & BMP are essentially the same, computers tend to use BMP file format and cameras tend to use RAW but both are uncompressed. RAW incidentally is not a file standard and may differ between manufacturers but is basically the uncompresed native image as recorded by the sensor then stored unchanged.	dugimodo (138)
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