Bit Depth Bit is on or off 1
Bit Depth Bit is on or off, 1 or 0 Byte is a string of 8 bits Kilobyte is 1, 024 bytes (over 8000 1’s and 0’s) Megabyte is 1024 kilobytes Gigabyte is 1024 megabytes Terabyte is 1024 gigabyte Petabyte is 1024 terabytes Exabyte… etc.
Bit Depth Each pixel is a byte (a string of 8 bits) Grayscale images use a value scale from 0 -255 or 256 levels from white to black.
Bit Depth Color is made of 3 monochromatic channels of 256 levels. Each channel is an 8 bit channel. Red (8 bit) + Green (8 bit) + Blue (8 bit) = 24 bit System
Bit Depth Each pixel from a grayscale is a string of 8 bits, or a byte. Each color pixel is 24 bits or 3 bytes. Bitmap: 4 pixels = 1 byte
Bit Depth 1024 bytes = 1 Kilobytes 1024 Kilobytes = 1 Megabytes 1024 Megabytes = 1 Gigabyte 1024 Gigabyte = 1 Terabyte
Bit Depth This image is 378 kilobytes or just under 400 k
Bit Depth HD 16: 9 Aspect Ration 1280 x 720 is 2. 64 MB SD 4: 3 Aspect Ratio 640 x 480 is 1. 2 MB
CODEC COMPRESSORS/DECOMPRESSORS GOAL – Reduce file size – Maintain quality • Image • Motion/speed Issues of Speed: Compression Decompression
Lossy vs lossless • • lossy compression is a data compression method which discards (loses) some of the data, in order to achieve its goal of reducing a file size. lossless compression is required for text and data files, such as bank records, text articles, etc.
CODECS Compression Schemes • • • JPEG: Joint Photographic Experts Group, 1986 Cinepak, Super. Mac Technologies for Apple Corp. , 1991 Sorenson, Apple Corp. for Quicktime, 1998 MPEG: Motion Picture Experts Group, 1988 Canada DVCPro by Panasonic, 1995 for News H. 264 (MPEG 4), 2003
SPEED: Bit Rate • Bit Rate is the number of bits or data than can be transmitted at one time. – – – Bit/s or Bps Kbit/s or Kbps Mbit/s or Mbps Gbit/s or Gbps Tbit/s or Tbps
Bit Rate/Data Rate • • 28 – 384 kbit/s –videoconferencing 1. 25 Mbit/s – VCD quality 3. 5 Mbit/s typ - Standard-definition television MPEG-2 5 Mbit/s typ – DVD quality MPEG-2 8 to 15 Mbit/s typ – HDTV quality MPEG-4 29. 4 Mbit/s max – HD DVD 40 Mbit/s max – Blu-ray Disc
Baud Rate • Baud Rate/Data Rate is the number of changes (packing or unpacking of bits) or symbols per second that can transmit across a data stream, such as an Ethernet cable, modem, satellite, wifi, etc.
Bandwidth • A telephone wire (modem) may transmit at a rate of 34, 200 bit/s. • Ethernet may transmit bits at 100 times the rate of a modem • Fiber Optics may be 1000 times faster than Ethernet.
Interlacing vs Progressive When interlacing is visible. Use the de-interlace filter found in the Video Folder (in the “effects” tab, in the bin). Drag into the clip that’s interlaced.
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