Canon XL1 3CCD manual Colour Depths

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1. Monochrome:

Æonly luminance (brightness) matters.

Æworks great for black‐and‐white movies.

ÆMost video codecs don’t have an explicit grayscale mode.

2. Red, Green, Blue (rGB):

ÆComputer screens and televisions are natively RGB—the screen has red, green, and blue phosphors for CRTs and planes for LCDs.

ÆUnefficient for video content, so RGB codecs aren’t used for broadcast video delivery anymore. However, RGB is widely used for screen recordings and motion graphics.

3. Y’CbCr:

ÆThese codecs encode luminance and two color‐difference channels

ÆBecause there are three colors, you can convert Y’CbCr to RGB for display.

ÆBy separating out the chroma and luma channels, you can keep the

critical luma information at full resolution and use less resolution for the chroma information.

ÆGreatly reduces data rate and processing requirements. You can convert RGB to

and from Y’CbCr adequately, but there are always some colors that are available in one mode but not the other, and there can be rounding errors as part of the conversion. (By working in tools that support 16‐bit‐per‐channel RGB, like Adobe After Effects® software, you significantly improve the quality of this conversion)

COLOUR DEPTHS

ÆDefine the precision of the colors and determine how many gradations of intensity there are.

ÆMeasured in the number of bits per channel (bpc)

Categories:

1. 8‐bit (indexed) color (often called 8‐bit or 256 color)

Ædoesn’t work well for video because even the simplest scenes use more than 256

colors. The only significant format that still requires 8‐bit indexed color is GIF.

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Contents How it works FeaturesCool stuff to play with and use Page Tips & Terminology Depth of Field Focus Composition Tip Video Audio Control HardwareRCA XLR Audio Paths Video PathsRifle Mic SoundMaking the Mic Stereo Shure MixerDigital Audio Recording XL1 Audio GuideDigital audio modes on the XL1 Digital FeaturesProcedure Lighting Page NEW Terms Tips Video Compression CompressionDVD Formats Features of CompressionHuman Senses FundamentalsInternet Formats Mobile DevicesTypes of Compression HOW Compression WorksColour Modes Frame Types and CompressionColour Depths Colour Sampling Sample Used Sufficient for Audio CompressionBIT Depth DVD, DATChannels Page Page Signal Formats and Cables Page ANALOG‐TO‐DV Converters Digital formats Choosing the right capture codec Exporting video Understanding preprocessing Deinterlacing video Scaling Encoding Page Adjusting the frame rate Negotiating Frame Dropping Choosing a compression format Windows media players Windows media audio Wma codecs RealMedia Video Codecs PNG IMA Extras