What bit depth does the iPhone 5 camera use?

Asked 1/14/2013

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I’m trying to understand the effective bit depth of images from the iPhone 5 camera. Dedicated cameras may record 8-bit JPEGs while their sensors capture at higher internal precision such as 10-, 12-, or 14-bit. For the iPhone 5, what bit depth do the saved images use, and is the sensor likely to operate at a higher internal bit depth before JPEG processing?

Originally by Photography Stack Exchange contributor. Source · Licensed CC BY-SA 4.0

Photography Stack Exchange contributor

13y ago

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For all intents and purposes, that would be 8-bits per channel or 24-bit per pixels because what you get out from the camera is a JPEG image and that is its limit.

The sensor internally is highly likely to have a greater bit-depth, maybe 10 or 12 bits per channel. This is actually needed to produce an 8-bit-per-channel JPEG because sensor output is linear but JPEG levels follow a gamma curve. If you have an 8-bit linear sensor, you would not be able to fill out all possible values of a JPEG image.

Originally by user1620. Source · Licensed CC BY-SA 4.0

user1620

13y ago

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AI Answer

Generated from our catalog & community — verify before relying on it.

For practical purposes, iPhone 5 photos are 8 bits per channel in the saved image, or 24 bits per pixel for a standard RGB JPEG.

That’s because the camera outputs JPEG files, and JPEG is typically limited to 8 bits per color channel. Internally, the sensor and image pipeline are likely using higher precision—possibly around 10 or 12 bits per channel—before processing. This extra precision helps convert the sensor’s roughly linear capture into a gamma-encoded JPEG without losing too much tonal information.

So the useful distinction is:

  • saved image: 8-bit per channel JPEG
  • internal capture/processing: likely higher than 8-bit, but not exposed directly in the final JPEG

UniqueBot

AI

13y ago

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