2.4 Digital Image Capture and Storage

Digital cameras capture and store images using advanced technology. RAW format preserves maximum data, while JPEG uses compression for smaller file sizes. Bit depth affects color information, with higher depths offering more editing flexibility but larger files.

Memory cards store images, with capacity and speed influencing performance. Buffers enable high-speed shooting, while frame rates determine how many images are captured per second. These factors affect image quality, file size, and creative control in cinematography.

Image Formats and Compression

RAW Format and Bit Depth

Top images from around the web for RAW Format and Bit Depth

• 

  BMP file format - Wikipedia View original

  Is this image relevant?

• 

  File:Digital cinema formats.svg - Wikimedia Commons View original

  Is this image relevant?

• 

  BMP file format - Wikipedia View original

  Is this image relevant?

• 

  BMP file format - Wikipedia View original

  Is this image relevant?

• 

  File:Digital cinema formats.svg - Wikimedia Commons View original

  Is this image relevant?

1 of 3

Top images from around the web for RAW Format and Bit Depth

• 

  BMP file format - Wikipedia View original

  Is this image relevant?

• 

  File:Digital cinema formats.svg - Wikimedia Commons View original

  Is this image relevant?

• 

  BMP file format - Wikipedia View original

  Is this image relevant?

• 

  BMP file format - Wikipedia View original

  Is this image relevant?

• 

  File:Digital cinema formats.svg - Wikimedia Commons View original

  Is this image relevant?

1 of 3

• RAW format captures unprocessed image data directly from the camera sensor
• Preserves maximum amount of information for post-processing flexibility
• Requires specialized software for viewing and editing
• Larger file sizes compared to processed formats
• Bit depth refers to the number of possible values for each color channel
• Higher bit depth allows for more color information and smoother gradients
• Common bit depths include:
  • 8-bit (256 levels per channel)
  • 10-bit (1024 levels per channel)
  • 12-bit (4096 levels per channel)
  • 14-bit (16384 levels per channel)
• Higher bit depths result in larger file sizes but offer greater editing flexibility

JPEG and Compression Techniques

• JPEG (Joint Photographic Experts Group) stands as a widely used compressed image format
• Employs lossy compression to reduce file size while maintaining acceptable image quality
• Compression level can be adjusted to balance file size and image quality
• JPEG compression process involves:
  • Color space conversion from RGB to YCbCr
  • Chroma subsampling to reduce color information
  • Discrete Cosine Transform (DCT) to convert spatial data to frequency domain
  • Quantization to reduce precision of frequency coefficients
  • Entropy coding for final compression
• Codec (Coder-Decoder) refers to the software or hardware used for compression and decompression
• Different codecs optimize for various factors (file size, quality, processing speed)

Storage and Data Transfer

Memory Cards and Storage Technologies

• Memory cards serve as removable storage devices for digital cameras
• Common types include SD (Secure Digital), CF (CompactFlash), and XQD
• Key factors in memory card performance:
  • Capacity determines the total amount of data that can be stored
  • Speed class indicates minimum write speed (Class 10, UHS-I, UHS-II)
  • Read and write speeds affect data transfer rates
• Larger capacities and faster speeds generally come at a higher cost
• Some cameras feature dual card slots for increased storage or backup purposes

Buffer and Frame Rate Management

• Buffer acts as temporary high-speed storage for image data before writing to the memory card
• Allows for continuous shooting at high frame rates
• Buffer size varies between camera models and affects burst shooting capabilities
• Frame rate refers to the number of images captured per second
• Factors influencing frame rate include:
  • Sensor readout speed
  • Image processing power
  • Buffer size and write speed
  • File format and compression settings
• Higher frame rates enable capture of fast-moving subjects and smooth slow-motion footage
• Trade-offs between frame rate, image quality, and file size must be considered
• Some cameras offer variable frame rate options for creative control